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A dual-functional wave-power plant for wave-energy extraction and shore protection : A wave-flume study

Résumé : The fundamental roadblock toward commercial-scale wave power operations is cost. The main objective of this work was to address the cost challenge facing wave energy commercialization through cost-sharing with pile breakwaters to be built for shore protection. This was achieved in this study through a dual-functional wave-power plant for generation of wave-power electricity and protection against coastal erosion for sustainable coastal development. The dual-functional wave-power plant was formed by integrating oscillating-water-column (OWC) devices into a pile breakwater, with each pile being an OWC-pile equipped with a power take-off device. The power extraction efficiency and hydrodynamic characteristics of the dual-functional wave-power plant were measured in a wave flume under various wave conditions. An orifice was used at the top of the pneumatic chamber of each OWC-pile to simulate the power take-off device. To evaluate the performance of the power plant in wave power extraction and shore protection, the surface elevation and pressure inside the OWC chamber, as well as the scattered waves, were measured. It was found that comparing to a standalone OWC-pile device with an identical design and geometric characteristics, an OWC-pile in the dual-functional wave-power plant could achieve significantly larger power-extraction efficiency. Comparing to a pile breakwater with the same dimensions, the wave transmission and reflection of the dual-functional wave-power plant were both weaker, especially the wave reflection, which is beneficial for structure safety and shore protection. Based on the Froude’s law of similarity and an estimation of the effect of air compressibility at full scale, an evaluation of the performance of a dual-functional wave-power plant at full scale was also provided. The findings of this work promote close collaboration between wave-energy utilization community and the shore-protection community for commercial-scale deployment of wave energy converters and contribute to making wave energy economically competitive.
Domaine de référence : EMR
Auteur Xu Conghao, Huang Zhenhua
Année de parution : 2018.
Mots-clés : Marine renewable energy, Oscillating water column, Pile breakwater, Shore protection, Vortex shedding, Wave farm.
Type de document : Article de revue.
Exporter la référence : BibTeX | Zotero RDF | RIS (EndNote)

Novel smart inspection-class ROV for use in challenging conditions

Résumé : In this thesis, a novel smart inspection-ROV is described. The research addresses the need for a highly-capable ROV with abilities to carry out close-quarters inspections of marine renewable energy installations in their inherently challenging environments where strong waves, current and wind are the norm. The use of such an ROV can aid towards the reduction of levelised costs for generating electricity of these MRE devices through maintenance operations and support. The design, fabrication and integration of the inspection-class ROV (I-ROV) are detailed. To ensure that the ROV can operate within the challenging conditions associated with MRE sites it has been designed to be reconfigurable, with options to use different types of thrusters in different configurations. For robust control, the ROV combines a state-of-the-art navigational sensor suite with the enhanced OceanRINGS+ control system. The ROV has also been designed to incorporate fault-tolerant control through the use of active or passive thruster fault detection (FDI) subsystems. The development of all the subsystems within the ROV is documented along with the testing and validation of the full ROV in virtual (simulated) and real-world environments. The agile hardware-in-the-loop (HIL) development and testing of the thruster FDI subsystems are described, with results issued. The thesis concludes with a summary of the work conducted for the research and provides suggestions for future work.
Domaine de référence : EMR
Auteur Capocci Romano
Année de parution : 2018.
Type de document : Article de revue.
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Assessment of the power conversion of wave energy converters based on experimental tests

Résumé : Power estimation is the most important task in the performance assessment of wave energy converters (WEC). Depending on the type of WEC, power take-off (PTO) system, and available instrumentation, different approaches are usually applied to assess power from experimental tests. Since neither for tests execution nor for the analyses exist standard methodologies, the estimated power can significantly differ among the approaches, thus, introducing inaccuracies in the assessment of the WEC’s performance. This study analyzed an extensive set of experimental results of a WEC and applied different power estimation approaches to compare and validate the obtained results. The strengths and weaknesses of those methodologies were analyzed and discussed. The major outcomes were: (a) PTO damping characterization based on bench tests can lead to unrealistic values of the WEC’s absorbed power; (b) the hybrid (experimental plus numerical) approach provide more reliable results than the traditional ones; (c) the kinetic energy harvester approach underestimates power but can be useful for preliminary qualitative performance assessments; (d) the new proposed gross efficiency index allows the definition of upper boundaries for wave power conversion as well as the identification of the wave conditions for which WEC performance can be improved.
Domaine de référence : EMR
Auteur Rodríguez Claudio A., Rosa-Santos Paulo, Taveira-Pinto Francisco
Année de parution : 2018.
Mots-clés : Damping, Efficiency, Hydrodynamics, Numerical simulation, Power take-off, WEC.
Type de document : Article de revue.
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A New Model for Fatigue Load Sequence Effects in Offshore Wind Turbine Substructures and Its Implications for Design Life

Résumé : ABSTRACT Measurements at Offshore Wind Turbine (OWT) substructures show that typical loading patterns include overloads, underloads, and shifts in mean stress cycles, due to the everchanging wind direction. These events follow each other in time and
Domaine de référence : EMR
Auteur Dragt R. C., Hengeveld S. T., Maljaars J.
Année de parution : 2018.
Type de document : Article de colloque.
Source : International Society of Offshore and Polar Engineers
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Investigation on offshore wind turbine with an innovative hybrid monopile foundation : An experimental based study

Résumé : The support structure for offshore wind turbines (OWTs) plays significant roles in maintaining the structural stability and reducing the initial cost. An innovative hybrid monopile foundation for OWTs is proposed. The concept has a wider adaptability by using established knowledge to solve for new problems. A series of centrifuge tests is performed to investigate the behavior of this hybrid foundation system in extreme and service conditions. OWTs with the original monopile foundation as well as the wheel-only foundations are tested for comparisons, and two clay profiles are considered. The test results show that the hybrid monopile foundation provides larger ultimate bearing capacities compared to the traditional foundations. Two analytical methods are proposed to estimate the ultimate bearing capacity of this innovative design, and the results are calibrated by the centrifuge tests. In service conditions, the hybrid monopile foundation shows stronger cyclic resistances. Influence factors of the cyclic responses are summarized. An analytical solution is put forward to estimate the accumulated lateral displacement of the hybrid monopile foundation. A degradation factor is suggested based on the results of the centrifuge tests. The study aims to enrich the understanding of the innovative foundation concept and to provide design references for practical applications.
Domaine de référence : EMR
Auteur Wang Xuefei, Zeng Xiangwu, Li Xinyao, Li Jiale
Année de parution : 2019.
Mots-clés : Centrifuge modeling, Clayey soil, Cyclic behavior, Hybrid monopile foundation, Offshore wind turbine, Ultimate bearing capacity.
Type de document : Article de revue.
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Explicit Method to Account for Cyclic Degradation of Offshore Wind Turbine Foundations Using Cyclic Interaction Diagrams

Résumé : ABSTRACT Cyclic loading could lead to progressive degradation of soil in terms of plastic strain accumulation, pore pressure build up and changes in soil strength and stiffness. The present paper outlines an explicit method to predict the accumulate
Domaine de référence : EMR
Auteur Zorzi Gianluca, Richter Thomas, Kirsch Fabian, Augustesen Anders Hust, Østergaard Martin Underlin, Sørensen Søren Peder Hyldal
Année de parution : 2018.
Type de document : Article de colloque.
Source : International Society of Offshore and Polar Engineers
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Numerical study on ocean thermal energy conversion system

Domaine de référence : EMR
Auteur Li Dashu, Yue Juan, Zhang Li, Duan Xili
Année de parution : 2018.
Type de document : Article de revue.
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Dynamic responses of a floating tidal turbine with 6-DOF prescribed floater motions

Résumé : This study aims to reveal the dynamic response and power output characteristics of a floating tidal turbine with prescribed motions in six degrees of freedom. Floater motions were calculated in the time domain based on linear potential theory. Both wave-induced inflow fields and floater motions are considered in a modified blade element momentum theory model for rotor load simulation. Generator power production and loads on a reference tidal turbine system were investigated. The torque and thrust response spectra are found to be dominated by floater-motion-induced contributions, and two response peaks can be clearly identified. A cancellation effect occurs between direct wave effects and floater-motion-induced loads, and horizontal and vertical rotor positions can significantly affect the dynamic responses of the blade loads; the rotor should be placed close to the floater centre to avoid large floater-motion-induced velocity on the blade section. Sensitivity studies are carried out with varying significant wave heights and peak periods. These results may contribute to a general understanding of floater-induced dynamic loads on floating tidal turbines in a random sea.
Domaine de référence : EMR
Auteur Guo Xiaoxian, Yang Jianmin, Lu Wenyue, Li Xin
Année de parution : 2018.
Mots-clés : Blade element momentum, Dynamic response, Floating tidal turbine, Linear surface wave, Wave induced load.
Type de document : Article de revue.
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Cost-effective risk-based inspection planning for offshore wind farms

Domaine de référence : EMR
Auteur Papatzimos A. Koltsidopoulos, Dawood T., Thies P. R.
Année de parution : 2018.
Type de document : Page Web.
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Economic-financial modeling for marine current harnessing projects

Résumé : The exploitation of oceans is currently recognized as an abundant, geographically diverse and renewable source of energy which still remains largely untapped. Marine currents are, together with waves, one of the most promising sources of ocean energy thanks to their enormous potential for electricity production and their high predictability. Owing to the fact that the marine current harnessing industry has only just begun to demonstrate full-scale devices and device arrays, most of the research papers related to marine current harnessing technologies have been focused on improving their technical aspects. However, there is limited information as regards other aspects, such as those of an economic nature, that should be studied in detail in order not to compromise the future of these technologies. The objective of this research is to address this gap by providing an economic-financial methodology that will help quantify the profitability and feasibility of these renewable energy projects. The methodology developed considers the following aspects: (i) a definition of the fundamental variables of the economic model. (ii) a definition of its financing structure on the basis of the industry's common stockholder equity that partners must provide and the estimation of bank financing needs; (iii) a definition of the main components required to obtain the forecast balance, the forecast income statement and the forecast sources and application of funds for the entire service life of the project; (iv) a determination of the cost-benefit analysis, carried out using the information provided in the cash-flows of the project and the forecast sources and application of funds; (v) an analysis of the most important economic-financial ratios of the model and; (vi) the realization of a sensitivity analysis, with the aim of detecting business risks when fundamental variables of the model, such as investment, the annual energy production, the price of energy or the percentage of loan requested, among others, oscillate. The proposed model has been applied to a case study, after which it was found to provide a good profitability for the project and the stakeholders. The results also indicate that the variables that most affect the profitability of the project are the interest rate, the price of energy and the annual energy produced.
Domaine de référence : EMR
Auteur Segura E., Morales R., Somolinos J. A.
Année de parution : 2018.
Mots-clés : Economic-financial modeling, Marine current harnessing devices, Offshore renewable energy, Project profitability.
Type de document : Article de revue.
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Underwater manipulators : A review

Résumé : This paper describes the state-of-the art in the area of underwater robot manipulator systems. A brief introduction is given on the use of manipulators in various offshore industries for different subsea intervention applications. It provides a comprehensive summary of existing commercial and prototype underwater manipulators, covering relevant aspects such as design features, their capabilities and merits, and provides a detailed comparison. This is followed by a thorough analysis of advantages and disadvantages of both electrically and hydraulically actuated manipulators. Furthermore, a detailed description of commercially available underwater manipulator control systems is presented in order to provide a realistic picture of the existing technology and its limitation. In addition, an extensive bibliography covering research results in the field of control algorithms is presented, including low level motion control, high level kinematic control and motion planning schemes along with the implementation issues.
Domaine de référence : EMR
Auteur Sivčev Satja, Coleman Joseph, Omerdić Edin, Dooly Gerard, Toal Daniel
Année de parution : 2018.
Mots-clés : Manipulator control, Marine robotics, Robot arm, ROV, Underwater manipulation.
Type de document : Article de revue.
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Performance of monopile-friction wheel foundations under lateral loading for offshore wind turbines

Résumé : The new type of foundation which comprises a monopile and a friction wheel is an innovative solution for offshore structures subjected to large lateral loading and has not been extensively investigated. In this paper, two types of friction wheels, namely the solid wheel and gravel wheel, are integrated to a monopile respectively to perform as hybrid foundations. The hybrid foundations are examined under lateral loading via centrifuge tests and three-dimensional finite-element (FE) analysis. The results show that the introduction of the wheel significantly enhances the lateral bearing capacity and stiffness of the monopile. By means of FE analysis, the load transfer mechanism and interaction between the foundations and soils are illustrated to study how the solid wheel and gravel wheel contribute to the performance of the foundation system. Finally, parametric studies about the geometry of the foundations and loading conditions are carried out, which can be used as references for the preliminary design of the monopile-friction wheel foundation.
Domaine de référence : EMR
Auteur Yang Xu, Zeng Xiangwu, Wang Xuefei, Yu Hao
Année de parution : 2018.
Mots-clés : 3-D FE modelling, Lateral loading capacity, Monopile-friction wheel foundation, Parametric study, Soil-structure interaction.
Type de document : Article de revue.
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Novel energy coefficient used to predict efflux velocity of tidal current turbine

Résumé : The efflux velocity is the basis for the prediction of turbine wake. A novel energy coefficient is defined to propose a new theoretical equation to predict the efflux velocity of tidal current turbine in this paper. Several CFD cases with different tip speed ratio and solidity is conducted using the DES-SA model. In order to overcome the limitations of the axial momentum theory, the effects of tip speed ratio and solidity on the efflux velocity are studied and the energy coefficients with different tip speed ratio and solidity are determined using the proposed equation based on the CFD results. Several semi-empirical efflux velocity equations are finally proposed by fitting the equation of the energy coefficient with tip speed ratio. The application of these equations in the prediction of wake flow and the power calculation of tidal turbine are also introduced in this paper.
Domaine de référence : EMR
Auteur Wang Shuguang, Lam Wei-Haur, Cui Yonggang, Zhang Tianming, Jiang Jinxin, Sun Chong, Guo Jianhua, Ma Yanbo, Hamill Gerard
Année de parution : 2018.
Mots-clés : Efflux velocity, Energy coefficent, Tidal-current turbine, Wake.
Type de document : Article de revue.
Exporter la référence : BibTeX | Zotero RDF | RIS (EndNote)

Opportunistic Maintenance Model for Wind Turbine Based on Reliability Constraint

Résumé : Preventive maintenance of wind turbine can effectively improve the reliability of wind turbine. This paper firstly set single component reliability of wind turbine as constraint condition, single component minimum unit time maintenance cost as objective function to obtain optimal maintenance cycle and maintenance times. On this basis, repairing component which meet certain conditions, then build opportunistic maintenance model of wind turbine. Lastly, set the minimum total cost under opportunistic maintenance as objective function, the wind turbine availability as constraint condition, then solve this model to obtain optimal threshold of opportunistic maintenance and minimum total maintenance cost using genetic algorithm. The example analysis shows that the model can effectively save the total maintenance cost. This study has some reference significance for the maintenance department to make the maintenance plan.
Domaine de référence : EMR
Auteur Li Hongbo, Li Pei, Gao Nannan, Niu Lin, Zhang Yanyan, Bao Yongbin, Xu Wenqi
Année de parution : 2018.
Type de document : Article de revue.
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The effects of oblique waves and currents on the loadings and performance of tidal turbines

Résumé : Tidal energy exploitation is at an early deployment stage and costs need to be reduced to improve the long term economic viability of the sector. High costs of tidal turbines are, in part, the result of load uncertainties, which lead to the use of high factors of safety in the design to ensure survival. One of the most important causes of uncertainty is hydrodynamic loadings. To date, most of the scaled model experiments with horizontal axis turbines investigating this issue have been carried out with collinear wave and current directions. To the authors’ knowledge, the work presented herein is the first experimental investigation of a horizontal axis turbine model subjected to combined oblique waves and current. Turbine performance and loading are measured for a 1:15 scale model tested in the FloWave circular, combined wave and current basin at the University of Edinburgh (UK). Three different flow directions were tested and each of them were also combined with regular waves in three different directions non-collinear with the flow. Fifteen physical quantities were measured including flow velocity, rotor and foundation loads and turbine speed. Characterisation of loads and turbine performance in those oblique current and wave conditions are presented. Waves affect means and standard deviation of rotor power and thrust, but off-axis waves are associated with lower thrust loads than head-on waves. Compared to current only, rotor torque and thrust standard deviations are higher in the presence of waves and almost twice as high when the wave crest is parallel to the rotor plan.
Domaine de référence : EMR
Auteur Payne Gregory, Martinez Rodrigo, Bruce Tom
Année de parution : 2018.
Type de document : Article de revue.
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Recent Trends in Wave and Tidal Current Energy : A Review

Résumé : AbstractIn recent decades, the globally demand for renewable energy has continued to enhance, even with contrary economic conditions such as trade disputes, world economic recessions and falls in gas and oil prices. The potential of producing electric power from marine renewable energy is massive. Marine waves are being very familiar as a renewable resource to be exploited for the sustainable generation of electrical power. The expectable resource features style ocean waves and tides chiefly attractive for power generation and beneficial when comparing to other sources of renewable energies. The proposed review will specifically highlight the main wave energy conversion projects around the world. The wave and tidal energy is having more and more support and interest as an auspicious renewable resource to replace part of the energy supply, although it is still immature compared to other renewable technologies. This work presents a complete analysis of the wave energy technology, starting with the characterization of this global resource in which the most suitable places to be exploited are displayed. The given paper discusses a complete review of wave and tidal energy technologies.Keywords: tidal, Marine, wave energy, tidal energyCite this ArticleRashmi Singh. Recent Trends in Wave and Tidal Current Energy: A Review. Journal of Offshore Structure and Technology. 2018; 5(1): 30–33p.
Domaine de référence : EMR
Auteur Singh Rashmi
Année de parution : 2018.
Type de document : Article de revue.
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Structural Identification for Dynamic Strain Estimation in Wind Turbine Towers

Résumé : Fatigue is a common issue in steel structures such as wind turbine towers, which is caused by cyclic wind and wave excitations. Therefore, estimation of the remaining fatigue life of the structural and foundation system is of concern. For this purpose, continuous monitoring of the structure is necessary to obtain strain data at fatigue critical points. Since installing and maintaining strain sensors in critical underwater location is difficult, strain data is often available only from a few sensors at accessible locations. Using these sparse sensors, the strain time histories at fatigue critical points can be estimated using estimation techniques. These techniques can identify the structural system using limited measured response data and a system model. In this paper, we implement a model updating approach followed by modal expansion to estimate the strain time history at critical points in a numerical case study representing an offshore wind turbine tower. The acceleration response of the structure is simulated using a finite element model and polluted with Gaussian white noise to represent measurements. The measurements are then used for model updating and strain estimation. The accuracy of the methods and their robustness to the measurement noise and model uncertainty are investigated. The estimated strain response time histories can later be used as input to an appropriate fatigue damage model to estimate the current state of fatigue damage in the system.
Domaine de référence : EMR
Auteur Nabiyan Mansure, Ebrahimian Hamed, Moaveni Babak, Khoshnoudian Faramarz
Année de parution : 2018.
Type de document : Chapitre de livre.
Source : Springer, Cham
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Impacts des sons anthropiques sur la faune marine

Résumé : Loin du monde du silence, le milieu marin doit se concevoir comme un environnement sonore. L’océan est porteur de bruits d’origine physique (vagues, pluie, glace, séismes) et biologiques (chant des baleines, clics des dauphins, claquements de crevettes ou d’oursins). Ce paysage acoustique est essentiel pour la faune marine. Il participe, entre autres, à l’orientation des larves, à la communication des animaux entre eux, à la détection de prédateurs. Toutefois, depuis un peu plus d’un siècle, les activités humaines modifient grandement ce paysage acoustique. Les bruits d’origine anthropique proviennent des navires, des installations posées en mer, des sonars et plus récemment de l’utilisation des énergies marines renouvelables. La faune marine perçoit-elle ces nouveaux sons ? La question de l’impact des sons anthropiques sur la faune marine se révèle un enjeu écologique et économique majeur pour les années à venir. Les auteurs montrent la diversitéde leurs effets sur la faune grâce à une approche multidisciplinaire associant la physique, la réglementation, la biologie et l’étude d’impact ; une place particulière est donnée aux premiers retours d’expérience de production d’énergies marines renouvelables (EMR) en Europe. Cet ouvrage se veut un premier état des lieux d’un champ de recherche qui ne fait que commencer.
Domaine de référence : EMR
Auteur Chauvaud Sylvain, Chauvaud Laurent, Jolivet Aurélie
Année de parution : 2018.
Mots-clés : Science / Life Sciences / Ecology.
Type de document : Livre.
Source : Quae
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Investigation of Hybrid Monopile Foundations for Offshore Wind Turbines under Lateral Cyclic Loading in Sand

Domaine de référence : EMR
Auteur Wang Xuefei, Zeng Xiangwu, Yang Xu, Yu Hao
Année de parution : 2018.
Type de document : Article de revue.
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Electro-mechanical modelling of tidal arrays

Résumé : The aim of this study is to present, compare and improve the options of power transmission for tidal current arrays. The potential to generate low or zero carbon power from the world’s tides is increasing as technology moves forward. The technically available tidal current energy resource, the resource that can be captured using existing technology, in the United Kingdom can supply a significant amount of the UK electricity demand. Even though tidal current devices have similarities to offshore wind turbines in many aspects, a number of characteristics differentiate the approach needed regarding power transmission and drive-train design. Some of these characteristics are: predictable direction and speed of the tidal current, predetermined available area in a tidal channel, less swept area due higher density of water, continuous underwater operation and smaller distances to shore. This thesis is based on the hypothesis that tidal current energy can be harnessed using today’s technology in an efficient manner. Technology progression never stops and as new materials and methods become available the cost of utilising tidal current energy will drop in the years to come. However, the research question that has to be asked is whether using today’s technology tidal arrays can be an alternative source of electrical power. In order to respond to this research question electromechanical models of tidal current devices have been developed in detail, from resource to the grid connection, using mathematical linear and non-linear programming in MATLAB/Simulink. The tidal models developed include the tidal resource, the tidal turbine with pitch control, geared induction and synchronous generators, the power electronics with the generator controller, the grid side controller, the cables for power transmission, the filters and the grid connection. All the modelling aspects of this study are presented in Chapter 3. Single tidal current devices were compared using different generator technologies, squirrel cage induction generator or permanent magnet synchronous generator, and different location of the power converters, in the nacelle near the generator or many kilometres apart from the generator. Regarding the generator technology, results showed that even though differences are minor, the permanent magnet synchronous generators are more efficient. Regarding the location of the power converters results showed that positioning the power converters in the nacelle always yields fewer electrical losses but component accessibility is minimised due to the underwater operation of the tidal current device. A key focus aspect of the study is the power transmission option with onshore converters which is presented in detail. Using this concept it is possible to generate electricity from tidal current devices but at the same time keep the highest possible system reliability despite the continuous underwater operation. This concept has been used in the first demonstration tidal current arrays developed by Andritz Hydro Hammerfest. What is more, data provided by Andritz Hydro Hammerfest were utilised in order to validate the simulation models. In this study a step forward is taken regarding the concept of keeping the converter dry and controlling the tidal current generator from afar. An algorithm is developed to design power harmonic filters for systems that use long distance controls. Power harmonic filters allow the long distance control system to operate reliably under all conditions but generate significant electrical losses. The power harmonic filter design algorithm presented in this thesis estimates the exact filter parameters so that the filter ensures maximum system reliability and generate minimum possible losses. In addition tidal array topologies using this concept are developed. The final part of this thesis compares a number of different tidal array topologies based on resource to grid efficiency and component accessibility for maintenance. Results showed that when tidal current devices are clustered per four turbines on offshore platforms it is efficient to use as many clusters as possible connected to a single cable whose both ends are connected to the grid. Locating the power converters in the nacelle yields fewer electrical losses compared to locating the power converters on the offshore platform. However, the difference is minimised because the distance between the tidal current device and the offshore platform is the least possible. Having the power converters on an offshore platform is beneficial in terms of accessibility for maintenance and operation because they are not underwater. The results and the methodology from this thesis can be extended to other offshore renewable energy systems such as the wind and wave. In addition, this study can be used as a stepping stone for decision making by tidal current developers.
Domaine de référence : EMR
Auteur Sousounis Marios Charilaos
Année de parution : 2018.
Type de document : Article de revue.
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Method of Correcting Rotor Imbalance and Wind Turbine Thereof

Résumé : The present invention relates to a method of correcting rotor imbalance and a wind turbine thereof. The correction method comprises measuring the vibrations within at least one time window and determining an imbalance factor and an imbalance phase. The values of the parameters in the equation for calculating the correction action are then updated based on the imbalance factor and an imbalance phase. A correction angle for each of the wind turbine blades is calculated using these adjusted parameters. The correction angle is used to aerodynamically balance the rotor, and a model may be used to determine the initial values of the parameters. Another imbalance factor and imbalance phase is determined based on another set of measurements. This imbalance factor is then used to calculate a mass moment for correcting the mass imbalance in the wind turbine blades. The weight and location of a balancing mass is finally calculated based on this mass moment and installed in the respective wind turbine blades.
Domaine de référence : EMR
Auteur Pedersen Keld Stefan
Année de parution : 2018.
Mots-clés : correction, imbalance, rotor, turbine, wind.
Type de document : Brevet.
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Accelerated life testing study of a novel tidal turbine blade attachment

Résumé : This paper describes the setup and some results of an accelerated life testing study of a tidal turbine blade attachment, which involved high-cycle fatigue testing of a tidal turbine subsystem at the Large Structure Laboratory of the National University of Ireland Galway (NUI Galway). Tidal turbines are in an early stage of development, which implies that there is no standard design and many different approaches are emerging in the market. The subsystem described in this paper is a 3/8 scaled down part of a 10-blade hubless turbine, developed by OpenHydro, a company specialising in the design, manufacture, installation, and maintenance of marine turbines generating renewable energy from tidal streams. The subsystem consists of a blade and a sector of the rotating ring. The sample was installed on an existing 10 m × 6 m × 6 m reconfigurable test frame and was loaded with a servo-hydraulic actuator controlled by an advanced software system, which allowed for an accurate sinusoidal load-controlled high-cycle fatigue test. The sample was loaded at four different levels to accumulate damage representative of a typical tidal turbine deployment life. The main objective of the test was to analyse the structural behaviour of the attachment system solution (blade-rotating ring) under fatigue load, particularly the internal structural welds, and to validate previously developed numerical models. To address all the requirements and to obtain valuable data, a large experimental test was set up. A total of 110 channels in a multi-channel data acquisition system were used to simultaneously acquire strain, displacement, and load data. Accurate measurements of temporal deformations and movement in a 3D field at the rear side of the ring were also acquired using a Digital Image Correlation system. The mechanism of failure was expected to be fatigue crack propagation at locations pre-determined in a structural analysis of the system.
Domaine de référence : EMR
Auteur de la Torre Oscar, Moore Daithi, Gavigan Declan, Goggins Jamie
Année de parution : 2018.
Mots-clés : Fatigue testing, Marine renewable energy, Ocean engineering, Structural testing, Tidal turbine subsystem.
Type de document : Article de revue.
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System and method for controlling offshore floating wind turbine platforms

Résumé : A method for controlling an inclination of a floating wind turbine platform comprising a generator, a set of turbine blades connected to a shaft inside a turbine nacelle, the turbine nacelle being mounted onto a tower, and at least three stabilizing columns is presented. Each of the at least three stabilizing columns have an internal volume for containing ballast. Position data associated with an orientation of the floating wind turbine is received. A heel angle in reference to the floating wind turbine platform is determined based on the position data. A first signal for adjusting at least one of a blade pitch of the set of turbine blades, and a torque of the generator is sent based on the determined heel angle. A second signal for distributing the ballast among the at least three stabilizing columns is also sent. The second signal for distributing the ballast is based on the determined heel angle and the first signal.
Domaine de référence : EMR
Auteur Peiffer Antoine, Cermelli Christian, Roddier Dominique
Année de parution : 2018.
Mots-clés : pitch, platform, system, turbine, wind.
Type de document : Brevet.
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Fatigue of polyamide mooring ropes for floating wind turbines

Résumé : This paper describes a study of the fatigue characterization of polyamide mooring ropes for floating wind turbines. Under some conditions polyester ropes, which are favoured for offshore platform station-keeping, are too stiff for wind turbine moorings, and polyamide may be a suitable alternative. While early studies on fatigue of braided nylon ropes showed very short lifetimes some recent results have indicated that it is possible to significantly enhance lifetime by modifying rope construction and improving fibre coatings [1]. The fatigue results presented here for ropes from a different supplier, confirm this result. In order to develop an accelerated evaluation of the fatigue performance, heat build-up tests have been performed, and promising first results are shown. Finally, the influence of coating is examined by microscopy and yarn-on-yarn tests, in order to improve understanding of the fatigue mechanisms leading to failure.
Domaine de référence : EMR
Auteur Chevillotte Yoan, Marco Yann, Davies Peter, Bles Guilhem, Arhant Maël, Hénaff G.
Année de parution : 2018.
Type de document : Article de revue.
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Opportunistic Maintenance for Wind Turbines Considering External Opportunities – A Case Study

Résumé : This paper aims to develop an opportunistic maintenance (OM) policy for the generator of a hypothetical wind turbine using methods developed recently by the authors. The OM policy considers external opportunities caused by low wind speeds which produce little-to-no electric power. The results show that some cost savings are achievable by taking maximal advantage of these low-speed wind events, particularly when electricity prices are at their peak cycle.
Domaine de référence : EMR
Auteur Ba H. Truong, Cholette M. E., Borghesani P., Ma L.
Année de parution : 2018.
Type de document : Article de colloque.
Source : Springer, Cham
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Systems and methods for offshore electrical energy generation

Résumé : In various embodiments, an offshore electrical energy generator is disclosed. The generator includes a buoy configured to float on a body of water. A wind turbine is mounted to the buoy. An air storage tank is configured for submersion. An air compressor is stowed within the buoy and coupled to the wind turbine and configured to charge the air storage tank in response to receiving wind energy collected by the wind turbine. An expansion turbine is stowed within the buoy and is configured to receive compressed air stored within the air storage tank and to decompress the compressed air to generate electrical energy.
Domaine de référence : EMR
Auteur Sinclair Nathan A., Wilkinson David P., Kilpatrick Jeffrey P.
Année de parution : 2018.
Mots-clés : air, electrical, energy, turbine, wind.
Type de document : Brevet.
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Integration of Distributed Energy Resources into Offshore and Subsea Grids

Résumé : The main goal of this paper is to outline characteristics and critical aspects related to the design and operation of offshore and subsea electric distribution grids, particularly in the case of high penetration of distributed and intermittent renewable energy sources. At first, the paper provides an overview of electric loads operating in the ocean environment, surveys their power and energy demands and presents their main operational characteristics and corresponding maturity of technology. Subsequently, the potential of marine renewable energy sources is identified by analyzing their degree of development, typical power range and suitability to supply the offshore loads. Based on an up-to-date review of previous studies and real test cases, this paper shows how conditions to enable the development of “offshore smart grids” can be met and it outlines emerging trends in the electrification of the ocean space.
Domaine de référence : EMR
Auteur Nejati Fard Razieh, Tedeschi Elisabetta
Année de parution : 2018.
Type de document : Article de revue.
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CFD Validation of Scaled Floating Offshore Wind Turbine Rotor

Résumé : Offshore wind turbines are lucrative than land based turbines for its high and consistent wind speed. Since the floating wind turbines are economical than gravity based or fixed bottom type wind turbines, offshore wind industry is exploring all possible ways to adopt well established oil and gas floating platform technologies. Unlike fixed bottom wind turbines, floating platform is subjected to complex motions in all 6 degrees of freedom that introduces new challenges in predicting the aerodynamic forces on the rotor. The conventional approach to determine the aerodynamic forces is not applicable for offshore floating turbines that is subjected to hydrodynamic and all other forces. The current study is focused on computationally validating the scaled model of NREL 5MW wind turbine that is experimentally investigated for various frequencies of platform surge motions at University of Strathclyde. The thrust forces and rotor torque are computed by numerically simulation and compared with experimental outcome showing a good agreement in the trend. The minor deviation in the aerodynamic forces is attributed to the higher prediction of lift and drag forces by XFOIL.
Domaine de référence : EMR
Auteur Sivalingam K., Davies P., Wala A. A. Singapore, Day S.
Année de parution : 2018.
Mots-clés : Automotive components, Blades, component, Computational modeling, formatting, insert (key words), Rotors, style, styling, Surges, Velocity control, Wind turbines.
Type de document : Article de colloque.
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Offshore Floating Structures

Résumé : An offshore floating structure such as a wind turbine includes a number of improvements. The floating structure can include a chain engaging system configured to prevent any lengthwise movement of a mooring chain. The floating structure can also include a mooring fixture pivotally coupled to the hull to prevent shock loads from being transmitted directly from the mooring line to the hull. The floating structure can also include installation aid structures that provide additional water plane area and/or buoyancy to the structure. The floating structure can also have a hull that is optimized for use as an offshore wind turbine.
Domaine de référence : EMR
Auteur Zou Jun, Udoh Ikpoto
Année de parution : 2018.
Mots-clés : chain, floating, iass, mooring, structure.
Type de document : Brevet.
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Underwater operational noise level emitted by a tidal current turbine and its potential impact on marine fauna

Résumé : Marine renewable energy development raised concerns over the impact of underwater noise. Here we assess the acoustic impacts of an operating tidal current turbine (Paimpol-Bréhat site, France) on marine fauna. Its source level (SL) has been measured in situ using 19 drifting transects at distances between 100 m to 2400 m from the turbine. SL ranged from 118 to 152 dB re1 μPa@1 m in third-octave bands at frequencies between 40 and 8192 Hz. It is comparable to the SL of a 19 m boat travelling at 10kt speed. This SL was used to estimate the impact of this noise type based on acoustic propagation simulations. The acoustic footprint of the device corresponds to a 1.5 km radius disk. Our results show that within this area of greatest potential impact, physiological injury of the hearing apparatus of invertebrates, fishes and marine mammals is improbable. Behavioral disturbance may occur up to 1 km around the device for harbor porpoises only. This is of little concern for a single turbine. However, greater concern on turbine noise impact, particularly on behavioral reactions has to be granted for a farm with up to 100 turbine. The lack of consolidated knowledge on behavioral disturbances identifies the needs for specific research programs.
Domaine de référence : EMR
Auteur Lossent J., Lejart M., Folegot T., Clorennec D., Di Iorio L., Gervaise C.
Année de parution : 2018.
Mots-clés : Fishes, Invertebrates, Marine mammals, Noise impact, Operating tidal current turbine, Third-octave source level.
Type de document : Article de revue.
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Seismic considerations in design of offshore wind turbines

Résumé : Interest in renewable and clean energy over the past decade has motivated immense research on wind energy. The main issues in design of offshore wind turbines in regions of recent development have been aero- and hydro-dynamic loads; however, earthquake is a design concern in seismic areas such as East Asia and Western United states. This paper reviews the state of practice in seismic design of offshore wind turbines. It is demonstrated that wind turbines are in particular vulnerable to vertical earthquake excitation due to their rather high natural frequencies in vertical direction; however, inclusion of the radiation damping could contribute considerably reduce the earthquake loads. Moreover, it is demonstrated how soil nonlinearity could lead to settlement and permanent tilting of offshore wind turbines on caisson foundations or tripods. Using these cases, the paper demonstrates that the design of offshore wind turbines for earthquake loading is driven by performance-based considerations.
Domaine de référence : EMR
Auteur Kaynia Amir M.
Année de parution : 2018.
Mots-clés : Earthquake response, Hysteretic damping, Permanent tilt, Radiation damping, Seismic performance, Soil-structure interaction, Wind turbine.
Type de document : Article de revue.
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A Framework to Improve the Coexistence of Maritime Activities &amp ; Offshore Wind Farms

Résumé : The increasing number and size of offshore wind farms (OWFs), combined with the ambitious plans for future developments in the sector, portray a bleak outlook for ‘traditional’ maritime and marine players. The sustained growth of OWFs can cause conflict with other marine users, and thus certain risk control options (RCOs) may need to be adapted in order to maintain navigational safety and reduce the environmental impact of such installations; introducing such measures, however, may be counter-productive in terms of energy efficiency or financial sustainability. This leads to questions such as ‘is there a point when implementing certain RCOs actually makes an OWF project unfeasible’?In this discussion paper, we describe a holistic and integrated framework that allows decision makers to evaluate the safety, energy efficiency, environmental impacts and financial sustainability aspects of OWFs. We consider a selection of vital factors and parameters in the current framework, and discuss how the different data sets can be integrated into a single framework. We also describe a novel evaluation tool that can allow users to ‘plot’ the output of the proposed framework in a spider diagram form. We conclude by discussing how the proposed work can be employed to optimize the use of limited sea-space.
Domaine de référence : EMR
Auteur Mehdi Raza Ali, Schröder-Hinrichs Jens-Uwe, Ölçer Aykut I., Baldauf Michael
Année de parution : 2018.
Type de document : Chapitre de livre.
Source : Springer, Cham
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A SWOT Analysis of the Marine Energy Sector at the European Level

Résumé : The present work aims to present the main potential sources of marine renewable energy: offshore wind and ocean energy (wave, tide, marine currents, temperature gradients, salinity gradients) and their social and environmental impact to make an analysis of the degree of capitalization of these alternative energy sources. The main objective of the proposed research is to identify the most relevant strengths, weaknesses, opportunities and threats (SWOT) in order to outline an overview of the use of the renewable marine energy resources at the European level that is to identify the possibilities of increasing the quota of exploiting the potential of the marine energy sector.
Domaine de référence : EMR
Auteur Stingheru Cristian, Gasparotti Carmen, Raileanu Alina, Rusu Eugen
Année de parution : 2018.
Type de document : Article de revue.
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An open-source comprehensive numerical model for dynamic response and loads analysis of floating offshore wind turbines

Résumé : This paper presents the development of a comprehensive open-source numerical model to study the dynamic response and load analysis of floating offshore wind turbines. The model accounts for the wind inflow, rotor aerodynamics, multibody structural model of the system, wave and current kinematics, hydrodynamics, and mooring-line dynamics. This coupled simulation tool can be used for analysis, optimization and preliminary design to determine the technical and economic feasibility. Several verification and validation cases are performed to show the correctness of the numerical simulations. The results show that the proposed approach provides an accurate estimate of the wind turbine dynamics and loads. The simulation tool is then applied in the analysis of a 5 MW wind turbine aimed to characterize the dynamic response and to identify potential loads and instabilities resulting from the dynamic couplings between the turbine and the external conditions. This open-source fully coupled aero-hydro-elastic model provides a modular framework to enable investigating a variety of wind turbine configurations, support systems, and mooring lines. Therefore, it is expected that researchers and design engineers worldwide use the model to study, investigate and analyze different aspects of floating offshore wind turbine design, which results is the promotion and advancement of science and technology for floating offshore wind turbines.
Domaine de référence : EMR
Auteur Barooni M., Ale Ali N., Ashuri T.
Année de parution : 2018.
Mots-clés : Dynamic response analysis, Floating offshore wind turbine, Load analysis, Numerical model, Wind turbine design.
Type de document : Article de revue.
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Structural Health Monitoring for Offshore Wind Turbine Towers and Foundations

Résumé : Abstract Structural Health Monitoring (SHM) of wind turbines can be used for verification and investigation of uncertainties in design, as well as provide input for possible future design optimization. It may also provide early warning of degradatio
Domaine de référence : EMR
Auteur Rahim A., Sparrevik P., Mirdamadi A.
Année de parution : 2018.
Type de document : Article de colloque.
Source : Offshore Technology Conference
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Development and Testing of Remotely Operated Vehicle for Inspection of Offshore Renewable Devices

Résumé : This paper presents novel aspects of a Remotely Operated Vehicle (ROV) designed to inspect offshore renewable energy devices. The relationship of some design aspects of the ROV to resilient systems is discussed, focusing on the navigation system, control system and novel reconfigurable propulsion system. The design and development of these aspects of the ROV are presented with initial test results illustrated. Finally, conclusions and future work suggestions are put forward.
Domaine de référence : EMR
Auteur Capocci Romano, Omerdic Edin, Dooly Gerard, Toal Daniel
Année de parution : 2018.
Type de document : Article de colloque.
Source : Springer, Cham
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Numerical Research of the Effect of Surface Biomimetic Features on the Efficiency of Tidal Turbine Blades

Résumé : Horizontal-axis axial flow tidal current turbine is regularly used to exploit the kinematic energy in tidal currents. However, the scaling up of tidal current turbine is very difficult. This is because strong tidal current only exists in the underwater region close to water surface, which implies that scaling up by enlarging rotor size is not always applicable to tidal current turbines. Hence, scaling up by improving the energy capture efficiency of the tidal turbine blade becomes a plausible choice. For this reason, apart from the numerous researches based on conventional aerodynamic and hydrodynamic theories, improving efficiency by biomimetic method is attracting increasing interest in recent years. It has been proved that leading-edge tubercles have positive contribution to improving the efficiency of tidal turbine blade. However, leading-edge tubercles can be made on blade only in the manufacturing process, as the post-production of them is quite difficult. Thus, how to improve the energy capture efficiency of the existing blades becomes a challenging issue. To address this issue, numerical research of the effect of surface biomimetic features on blade efficiency is conducted in this paper. For the sake of simplicity, surface bumps are investigated in this preliminary research in order to obtain a basic understanding of the effect of surface biomimetic features. In the research, the influences of surface bumps on blade surface pressure and the ratio of lift to drag forces are investigated in different bump array scenarios and at different tidal current speeds and the angles of attack. The calculation results have shown that surface bumps do improve the ratio of lift to drag forces of the blade in spite of their array arrangement, the angle of attack and tidal current speed. This suggests that the energy capture efficiency of both new and existing blades can be further improved if appropriate biomimetic features are deployed on the blade surfaces.
Domaine de référence : EMR
Auteur Yang Wenxian, Alexandridis Theodoros, Tian Wenye
Année de parution : 2018.
Mots-clés : biomimetics, blade, energy capture efficiency, tidal current turbine.
Type de document : Article de revue.
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An integrated operational system to reduce O&M cost of offshore wind farms

Domaine de référence : EMR
Auteur Wang K., Jiang X., Negenborn R. R., Yan X., Yuan Y.
Année de parution : 2018.
Type de document : Article de colloque.
Source : CRC Press
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Wave energy assessement for Northern Spain from a 33-year hindcast

Résumé : The wave energy resource along the Northern Spanish coast is determined, for a period of 33 years (1979–2012) based on hindcast results of WAVEWATCH III for the Atlantic ocean area, coupled with the SWAN model for the coastal areas, and using surface winds from ECMWF's ERA- Interim data base. Results are validated with buoy data, in order to evaluate the model's accuracy. Statistical analysis of the wave parameters and wave power results are presented. The analysis was carried out for a coarse grid, on the North of Spain, and for three local areas with a finer mesh: Northwest Galicia, the area between Cape San Adrián and Cape Ortegal and Santander. The case studies include a more realistic perspective of the amount of energy that can be extracted with a wave energy converter, by adopting examples of a large and a small device. A seasonal variability evaluation is done for the nested areas through the analyzes of the seasonal average wave power resource for the different locations, throughout the 33 year hindcast, and the joint distributions of significant wave height and peak period for the number of occurrences and wave power.
Domaine de référence : EMR
Auteur Bento A. Rute, Martinho Paulo, Guedes Soares C.
Année de parution : 2018.
Mots-clés : Marine renewable energies, North of Spain, Resource assessment, SWAN, Wave energy, WAVEWATCH III.
Type de document : Article de revue.
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Combining a spar type floating offshore wind turbine with a current turbine

Résumé : With the shift towards a more sustainable energy society, the increase in the electricity produced by renewable energy sources is steadily rising. However the cost of renewable energy sources still remains high compared to the traditional fossil fuel based energy sources. With the total worldwide energy demand also rising, combining renewable energy sources helps to reduce the cost through a shared infrastructure and increase in energy production. This thesis investigates the feasibility of a combination of floating offshore wind and marine current energy. As a basis the Hywind spar type floating offshore wind turbine is used. This 5 MW system is combined with a 1 MW marine current turbine. The characteristics of the current turbine will be examined with the program Aerodyn and the blades are designed with the program Harp_opt. As a cost reduction, the effect of scaling down the weight of the mooring system in combination with reversing the direction of the thrust of the current turbine is also investigated.<br/><br/>The program ANSYS AQWA is used to investigate the dynamic behavior of the<br/>combined system. The thrust forces of the wind and current turbines are calculated via an external python server and added to the simulation in AQWA. The structure is modeled in a rigid body approximation, assuming no structural deformations. The behavior of the combined system is investigated in 3 operational and 1 survival load case. The operational load cases represent the environmental conditions of the cut-in, rated and cut-out wind speed of the wind turbine. In the fourth load case the system is subjected to survival conditions and the direction of the thrust of the current turbine is reversed. The environmental conditions are simulated with a steady wind velocity and the sea state is modeled using the JONSWAP wave spectrum. In all 4 load cases the system is subjected to a strong current.<br/><br/>By using a levelized cost of energy prediction model, a first estimation of the levelized cost of energy of the combined system is obtained. Adding a current turbine to the Hywind spar increases the cost of the initial investments and operational cost of the system, but also increases the total energy generation. Compared to the original Hywind spar, adding a current turbine to the system lowers the levelized cost of energy from 149.4 €/MWh to 142.3 €/MWh. Scaling down the weight of the mooring system lowers the levelized cost of energy to 141.9 €/MWh.<br/><br/>From the results of the simulations it is found that using the current turbine during survival conditions has a positive effect on the motions and maximum tension in the lines. It is concluded that by using the thrust of the turbine the weight of the mooring system could be scaled down, but the effect on the levelized cost of energy is minimal and doesn’t justify the increased risk of failure.<br/>
Domaine de référence : EMR
Auteur Haaker Joeri
Année de parution : 2018.
Type de document : Article de revue.
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An Electrochemist Perspective of Microbiologically Influenced Corrosion

Résumé : Microbiologically influenced corrosion (MIC) is a major concern in a wide range of industries, with claims that it contributes 20% of the total annual corrosion cost. The focus of this present work is to review critically the most recent proposals for MIC mechanisms, with particular emphasis on whether or not these make sense in terms of their electrochemistry. It is determined that, despite the long history of investigating MIC, we are still a long way from really understanding its fundamental mechanisms, especially in relation to non-sulphate reducing bacterial (SRB) anaerobes. Nevertheless, we do know that both the cathodic polarization theory and direct electron transfer from the metal into the cell are incorrect. Electrically conducting pili also do not appear to play a role in direct electron transfer, although these could still play a role in aiding the mass transport of redox mediators. However, it is not clear if the microorganisms are just altering the local chemistry or if they are participating directly in the electrochemical corrosion process, albeit via the generation of redox mediators. The review finishes with suggestions on what needs to be done to further our understanding of MIC.
Domaine de référence : Biocorrosion
Auteur Blackwood Daniel, Blackwood Daniel J.
Année de parution : 2018.
Mots-clés : anaerobic, electrochemistry, mechanisms, microbiologically influenced corrosion.
Type de document : Article de revue.
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Microbiologically influenced corrosion in floating production systems

Résumé : Microbiology Australia, bringing Microbiologists together
Domaine de référence : Biocorrosion
Auteur Suarez Laura Machuca, Polomka Anthony
Année de parution : 2018.
Type de document : Article de revue.
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Mitigation of Corrosion Problems in API 5L Steel Pipeline–A Review

Résumé : The worst nightmare of the oil and gas industry which must not be taken lightly is the issue of corrosion which affects the pipes used for transportation of oil and gas. Corrosion problems need to be properly understood in order to prescribe the necessary kind of treatment that will ensure a long life span for the pipeline. This paper gives a comprehensive review of corrosion problems in API 5L steel pipeline and the ways to mitigate the corrosion problems. Proper control and prevention of corrosion in API 5L steel would ensure long life span of the pipe, uninterrupted flow of products, reduction in shutdown time and generate more revenue for the industry. Oil and gas materials last longer when both inhibitors and protective coatings are used together or when protective coating is used together with cathodic protection
Domaine de référence : Biocorrosion
Auteur Kolawole F. O., Kolawole S. K., Agunsoye J. O., Adebisi J. A., Bello S. A., Hassan S. B.
Année de parution : 2018.
Type de document : Article de revue.
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A Mechanistic Approach to Understanding MIC by Metal-Depositing Bacteria

Résumé : Iron (Fe)- and manganese (Mn)-oxidizing bacteria are often cited individually and collectively as putative microorganisms for microbiologically influenced corrosion (MIC). The two groups of microorganisms have in common the ability to attach to surfaces and produce macroscopic accumulations (deposits) of metal oxides/hydroxides/oxyhydroxides that can influence corrosion of some metals and alloys in some environments. In all cases, once initiated, the corrosion is independent of the activities of the colonizing species. Despite the phylogentic diversity of Fe-oxidizing bacteria the following sections will deal with corrosion mechanisms attributed to neutrophilic, lithotrophic, microerophilic Fe-oxidizing bacteria (FeOB). The mineralogy of biologically oxidized Fe is consistent over a wide range of environments. All FeOB produce dense deposits that can cause corrosion of low alloy stainless steels directly, i.e., under deposit corrosion. Association of MnOB and other microorganisms may stabilize the under deposit corrosion on low alloy stainless steels. The influence of FeOB on the corrosion of carbon steel may be related to deposition of metal ions, causing galvanic corrosion or association with other corrosion-causing microorganisms. All MnOB produce manganese oxides that are strong naturally-occurring oxidizing agents that can cause ennoblement of low alloy stainless steels and increase corrosion currents on carbon steel in fresh water. Corrosion associated with manganese deposits depends on the relationship between the mineral deposit and the substratum.
Domaine de référence : Biocorrosion
Auteur Lee Jason, Little Brenda
Année de parution : 2018.
Type de document : Article de revue.
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Molecular Biological Tools in Concrete Biodeterioration – A Mini Review

Résumé : Concrete structures develop biofilms when exposed to various environments. At a certain stage, the microbial films destroy the concrete structures leading to significant deterioration. Culture-dependent techniques give an incomplete picture of the microbial communities on the concrete surface. Culture independent techniques or molecular biological tools pave a new way to analyze microbial communities involved in concrete biodeterioration. This study highlights the need to ‘build’ a database, for Microbiologically Influenced Concrete Corrosion (MICC) involving microbial groups that are being identified using culture dependent and independent techniques. The role of molecular tools such as 16S rRNA sequencing, denaturing gradient gel electrophoresis (DGGE), Fluorescent in situ hybridization (FISH), Real time Polymerase Chain Reaction (RT-PCR), microarray analysis, 2-Dimensional gel electrophoresis (2-DE) in analyzing microbial communities on the concrete structures have been reviewed in this paper.
Domaine de référence : Biocorrosion
Auteur Vishwakarma Vinita, Anandkumar Balakrishnan
Année de parution : 2018.
Mots-clés : 2-Dimensional electrophoresis, Concrete biodeterioration, DGGE, FISH, Microarray chips.
Type de document : Article de revue.
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Biofilm activity on corrosion of API 5L X65 steel weld bead

Résumé : This work aimed to identify microbial colonization and biocorrosion in welded seam areas of API 5 L X65 carbon steel, since microorganisms are ubiquitous and there is a lack of information on their biological and electrochemical interactions with these structures. In the present study, polished and unpolished welded coupons prepared by shielded metal arc welding were assayed to identify the effect of surface roughness and local changes in the metal microstructure on microbial colonization. Experiments were performed in glass cell vessels with fresh and sterile seawater to establish the presence or absence of microorganisms. For comparison, nonwelded coupons were simultaneously tested as a control. On the 15th day, both polished and unpolished welded coupons and the nonwelded coupons immersed in fresh seawater showed microbial colonization, though the corrosion products were more abundant for the welded coupons. Nevertheless, unpolished welded coupons showed a higher predominance of pitting around the beads than polished coupons. These results suggest that filler material creates conditions more favorable for biofilm development, thus intensifying the localized corrosion on the welds. It can be concluded that adhesion and subsequent biocorrosion are directly influenced by surface roughness, whereas microstructural modifications due to welding interfere little with microbial adhesion, regardless of the greater pit depths compared to those of nonwelded coupons. Additionally, although open circuit potential measurements indicated that metal surfaces are protected when coated with biofilms, pitting corrosion was more pronounced in welded coupons immersed in fresh seawater than in those immersed in seawater without microorganisms. Therefore, the use of open circuit analysis alone is not recommended for biocorrosion monitoring of welded coupons.
Domaine de référence : Biocorrosion
Auteur Liduino V. S., Lutterbach M. T. S., Sérvulo E. F. C.
Année de parution : 2018.
Mots-clés : Biocorrosion, Carbon steel X65, Pitting, Seawater, Welding.
Type de document : Article de revue.
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Laboratory investigation of microbiologically influenced corrosion of 2205 duplex stainless steel by marine Pseudomonas aeruginosa biofilm using electrochemical noise

Résumé : The corrosion mechanism of a 2205 duplex stainless steel (DSS) in Pseudomonas aeruginosa inoculated medium was investigated using the information of electrochemical current noise (ECN) transients derived from Hilbert spectra and surface analysis. The pit depths from confocal laser scanning microscopy (CLSM) were analyzed stochastically. Results showed that metastable pitting and stable pitting occurred simultaneously, and they were controlled by different mechanisms in the presence of P. aeruginosa. Metastable pitting occurred in the region uncovered by P. aeruginosa unlike stable pitting. P. aeruginosa likely dissolved the passive film and produced soluble CrO3, leading to stable pitting.
Domaine de référence : Biocorrosion
Auteur Zhao Yang, Zhou Enze, Xu Dake, Yang Yange, Zhao Ying, Zhang Tao, Gu Tingyue, Yang Ke, Wang Fuhui
Année de parution : 2018.
Mots-clés : A. Duplex stainless steel, B. SEM, C. Microbiological corrosion, C. Pitting corrosion.
Type de document : Article de revue.
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The influence of surface microbial diversity and succession on microbiologically influenced corrosion of steel in a simulated marine environment

Résumé : To explore how a succession of bacteria grown on steel coupons in a marine environment can influence their corrosion process, we designed a microcosm in laboratory to evaluate corrosion kinetics and microbial diversity over 30 days. The results described a clear influence of corrosion by a succession of different bacterial groups. During the initial period, 2–7 days, a sharp increase in the rate of corrosion was detected accompanied by the presence of Alteromonadaceae, Vibrionaceae, Oceanospirillaceae, Rhodobacteraceae, Rhodospirillaceae and Flavobacteriaceae bacteria families. After 15 days, representatives of families Piscirickettsiaceae and Pseudomonadaceae were also described, accompanied by a continuous corrosion process over the coupons. After 30 days, there was a sudden change in the profile of the bacteria present on the steel coupons, with a prevalence of Halomonadaceae family species, and establishment and continuity of the corrosion process by the biofilm grown on the coupons. The results describe differences in microbial diversity over the time, highlighting certain bacterial lithotrophic species that persisted for most of the experiment, through a complex association between bacteria and metal surfaces, which can be a new starting point for development and maintenance of a favorable microenvironment to accelerate corrosion processes.
Domaine de référence : Biocorrosion
Auteur Moura Vanessa, Ribeiro Iris, Moriggi Priscilla, Capão Artur, Salles Carolina, Bitati Suleima, Procópio Luciano
Année de parution : 2018.
Mots-clés : Carbon steel, Marine environmental, Microbial community, Microbiologically influenced corrosion, Steel coupons.
Type de document : Article de revue.
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Influence of inhibitors on the adhesion of SRB to the stainless steel in circulating cooling water

Résumé : Influence of the surface characteristics of three stainless steels (SS304, 316L and 317) and presence of scale inhibitors on adhesion kinetics of sulfate reducing bacteria (SRB) in circulating cooling water, were investigated by evaluating surface free energy, adhesion kinetic constants in a parallel plate flow chamber. Results show that the surface free energy values of SS317, SS316L and SS304 are −31.69, −24.18 and −13.92 mJ m−2, respectively. SS317 surface had higher surface hydrophobicity than SS316L and SS304. In the process of bacteria cells adhesion onto SS surfaces, electrostatic interaction for SS is slightly more than hydrophobic interaction. The number of adhering bacteria and the adhesion kinetic constants are different on the three types of stainless steel. The adhesion kinetic constants for SS317 and 316L are greater than that for SS304, which are 0.0354, 0.0282 and 0.0190 min-1, respectively. Scale inhibitors of hydrosy ethyl fork phosphonic acid (HEDP) and phosphono butane-1, 2, 4-tricarboxylic acid (PBTCA) have a certain influence on the initial adhesion of bacteria cell and adhesion kinetics constants are reduced in the presence of HEDP and PBTCA.
Domaine de référence : Biocorrosion
Auteur Liang R., Li J., Liu M., Huang Z. Y.
Année de parution : 2018.
Mots-clés : Bacterial adhesion, Parallel plate flow chamber, Scale inhibitor, Stainless steel, Sulfate reducing bacteria (SRB), Surface free energy.
Type de document : Article de revue.
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A review : microbiologically influenced corrosion and the effect of cathodic polarization on typical bacteria

Résumé : Microbiologically influenced corrosion is a serious type of corrosion as approximately 20% of the total economic losses. Sulfate reducing bacteria and Iron oxidizing bacteria are one of the typical representatives of the anaerobic and aerobic bacteria, which are ubiquitous in natural environments and corrode steel structures. Cathodic polarization has been recognized as an effective method for preventing steels from microbial corrosion. Although cathodic polarization method has been widely studied, the specific properties of cathodic current that influences the bacterial removal and inactivation remained largely unclear. This review is to show the main effects of Sulfate reducing bacteria and Iron oxidizing bacteria on metal decay as well as the inhibition mechanism of cathodic polarization in the study of bio-corrosion.
Domaine de référence : Biocorrosion
Auteur Lv Meiying, Du Min
Année de parution : 2018.
Mots-clés : Biofilm, Cathodic polarization, Iron oxidizing bacteria, Microbiologically influenced corrosion, Sulfate reducing bacteria.
Type de document : Article de revue.
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Factors Affecting Corrosion of Buried Cast Iron Pipes

Domaine de référence : Biocorrosion
Auteur Wang Weigang, Robert Dilan, Zhou Annan, Li Chun-Qing
Année de parution : 2018.
Type de document : Article de revue.
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A Combination of qPCR, RT-qPCR and NGS Provides a New Tool for Analyzing MIC Risk in Pipelines

Résumé : ABSTRACT Sampling of pigging debris was performed from three multiphase pipelines that previously were exposed to microbiologically influenced corrosion (MIC) due to high abundances of sulfate-reducing prokaryotes (SRP) and methanogens. Sampling was
Domaine de référence : Biocorrosion
Auteur Thomsen Uffe Sognstrup, Oehler Mike Christian
Année de parution : 2018.
Type de document : Article de colloque.
Source : NACE International
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Modeling of Microbiologically Influenced Corrosion (MIC) in the Oil and Gas Industry - Past, Present and Future

Résumé : ABSTRACT Microbiologically Influenced Corrosion (MIC) is a complex form of materials degradation caused by the biological activity of microorganisms such as bacteria, archaea and fungi. It is typically characterized by the presence of microbiologica
Domaine de référence : Biocorrosion
Auteur Wolodko John, Haile Tesfaalem, Khan Faisal, Taylor Christopher, Eckert Richard, Hashemi Seyed Javad, Ramirez Andrea Marciales, Skovhus Torben Lund
Année de parution : 2018.
Type de document : Article de colloque.
Source : NACE International
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MIC Considerations for Cathodically Protected Encased Ductile Iron Pipelines : A Case Study

Résumé : ABSTRACT There is a wide range of opinions about the proper method of corrosion control, including the need for cathodic protection, tight bonded coating and polyethylene encasement for ductile iron pipe. While polyethylene encasements are commonly
Domaine de référence : Biocorrosion
Auteur Giddings Jeffry B., Akhoondan Mersedeh, Bell Graham
Année de parution : 2018.
Type de document : Article de colloque.
Source : NACE International
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Pitting Corrosion Behavior of Carbon Steel in the Presence of Sulfate-Reducing Bacteria in H<sub>2</sub>S Environments

Résumé : ABSTRACT API-RP38 culture medium was used to culture sulfate SRB isolated from an oilfield wastewater sample. SRB test bottle method was used to verify bacterial activity, and SEM was employed for identifying the microbial morphology. Corrosion beha
Domaine de référence : Biocorrosion
Auteur Lei Ma, Junfeng Xie, MaoXian Xiong, Yan Li, Mifeng Zhao, Hua Wang
Année de parution : 2018.
Type de document : Article de colloque.
Source : NACE International
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Biofilm activity on corrosion of API 5L X65 steel weld bead

Résumé : This work aimed to identify microbial colonization and biocorrosion in welded seam areas of API 5 L X65 carbon steel, since microorganisms are ubiquitous and there is a lack of information on their biological and electrochemical interactions with these structures. In the present study, polished and unpolished welded coupons prepared by shielded metal arc welding were assayed to identify the effect of surface roughness and local changes in the metal microstructure on microbial colonization. Experiments were performed in glass cell vessels with fresh and sterile seawater to establish the presence or absence of microorganisms. For comparison, nonwelded coupons were simultaneously tested as a control. On the 15th day, both polished and unpolished welded coupons and the nonwelded coupons immersed in fresh seawater showed microbial colonization, though the corrosion products were more abundant for the welded coupons. Nevertheless, unpolished welded coupons showed a higher predominance of pitting around the beads than polished coupons. These results suggest that filler material creates conditions more favorable for biofilm development, thus intensifying the localized corrosion on the welds. It can be concluded that adhesion and subsequent biocorrosion are directly influenced by surface roughness, whereas microstructural modifications due to welding interfere little with microbial adhesion, regardless of the greater pit depths compared to those of nonwelded coupons. Additionally, although open circuit potential measurements indicated that metal surfaces are protected when coated with biofilms, pitting corrosion was more pronounced in welded coupons immersed in fresh seawater than in those immersed in seawater without microorganisms. Therefore, the use of open circuit analysis alone is not recommended for biocorrosion monitoring of welded coupons.
Domaine de référence : Biocorrosion
Auteur Liduino V. S., Lutterbach M. T. S., Sérvulo E. F. C.
Année de parution : 2018.
Mots-clés : Biocorrosion, Carbon steel X65, Pitting, Seawater, Welding.
Type de document : Article de revue.
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Methods to Evaluate Corrosion in Buried Steel Structures : A Review

Résumé : Around the world, there are thousands of metal structures completely or partially buried in the soil. The main concern in their design is corrosion. Corrosion is a mechanism that degrades materials and causes structural failures in infrastructures, which can lead to severe effects on the environment and have direct impact on the population health. In addition, corrosion is extremely complex in the underground environment due to the variability of the local conditions. The problem is that there are many methods to its evaluation but none have been clearly established. In order to ensure the useful life of such structures, engineers usually consider an excess thickness that increases the economic cost of manufacturing and does not satisfy the principles of efficiency in the use of resources. In this paper, an extended revision of the existing methods to evaluate corrosion is carried out to optimize the design of buried steel structures according to their service life. Thus, they are classified into two categories depending on the information they provide: qualitative and quantitative methods. As a result, it is concluded that the most exhaustive methodologies for estimating soil corrosion are quantitative methods fed by non-electrochemical data based on experimental studies that measure the mass loss of structures.
Domaine de référence : Biocorrosion
Auteur Arriba-Rodriguez Lorena-de, Villanueva-Balsera Joaquin, Ortega-Fernandez Francisco, Rodriguez-Perez Fernando
Année de parution : 2018.
Mots-clés : metal construction, qualitative methods, quantitative methods, soil corrosion, steel structures.
Type de document : Article de revue.
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Use of Next Generation Sequencing to Identify Sources of Microbial Contamination

Résumé : Abstract Management of bacteria remains a concern for most Operators and the ability for micro-organisms to generate hydrogen sulphide (H 2 S) that results in reservoir souring and microbiologically influenced corrosion is well documented. This pape
Domaine de référence : Biocorrosion
Auteur Chalmers Alison, Gale Andrew, Birnie Mark, Linde Anja, Millar Andrew
Année de parution : 2018.
Type de document : Article de colloque.
Source : Society of Petroleum Engineers
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Comparing Oilfield Biocides for Corrosion Control Using a Laboratory Method for MIC Generation Under Oilfield-Relevant Conditions

Résumé : Abstract The pipelines and vast infrastructure required for the production and transport of oil and gas are largely constructed of carbon steel. This material is highly susceptible to damage and failure as a result of direct or indirect Microbially
Domaine de référence : Biocorrosion
Auteur Eibergen Nora, Maun Philip, Caldwell Brittany, Widera Imke, Morris Brandon E. L., Wunch Kenneth, Kraan Van Der, M Geert
Année de parution : 2018.
Type de document : Article de colloque.
Source : Society of Petroleum Engineers
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Influence of soil microorganisms on metal corrosion of underground pipelines

Résumé : There have been revealed and summarized the regulari- ties in biocorrosion of steel 17G1S-U, which is traditionally used for manufacturing oil and gas mains. The basic regulari- ties of biocorrosion processes in the 17G1S-U pipe steel under the influence of SRB Desulfovibrio Sp. strains Kyiv-10 was ob - tained by weight-loss testing and surface analysis techniques. Effective inhibitors are proposed, which allow protecting ste- el 17G1S-U against the development of anaerobic corrosion under the influence of sulfate-reducing bacteria (SRB). The effectiveness of inhibitors is estimated by the degree of their protective effect. The porous structure of the surface film con - tributes to the initiation of localized corrosion. Damage analy- sis of the specimen surface corroded under different test condi- tions was performed.
Domaine de référence : Biocorrosion
Auteur Maruschak Pavlo
Année de parution : 2018.
Type de document : Article de revue.
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Pipelines corrosion during water supply process

Résumé : Buildings and structures reliability is a key question in human life and activities. Corrosion processes affect reliability of all water supply and distribution systems in buildings and structures.This research provides results of the tests for corrosion rate and for the time of steel water-pipes inhibition of corrosion in Samara. A gravimetric method was used to determine corrosion rate. The test subjects were surface (the Volga river) and underground (water treatment facilities of 113 km, Kuibyshev district) water supply sources. These tests proved that river water was highly aggressive in respect to other materials. Here the corrosion rate reached 0.1665 g/(m 2 /h) during in the 5 th month of exposure, and the specimens were damaged by pitting corrosion (within 1 month) and by cankers (within 5 months). The value of the corrosion rate in underground source water was within the range of 0.01-0.06 g/(m 2 /h), and the specimens were not subjected to any significant corrosion damage. The time of experience was not enough for complete inhibition of corrosion. The authors studied a sample with 50-year operational lifetime and proved that all corrosion processes affecting this sample had stopped, this sample material integrity had been pre-served which meant that steel pipes complete inhibition of corrosion was possible. The experiments also showed that the inner surface of the pipe was later filled with corrosion deposits. The thickness of corrosion deposits in the tray zone reached up to 7 mm.
Domaine de référence : Biocorrosion
Auteur Atanov Nikolay, Gorshkalev Pavel, Chernosvitov Michail, Smirnova Angelina
Année de parution : 2018.
Type de document : Article de revue.
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Exploration of sulfate reducing bacteria from polluted waters

Résumé : Sulfate reducing bacteria (SRB) was successfully isolated from Estuary Dam in Suwung Denpasar, Indonesia. This estuary catches highly polluted water from Badung River which runs across and hence carries pollution due to waste disposal from Denpasar City. SRB was studied in detail for their ability to reduce sulfate to sulfide with organic material as an oxidizing agent. SRB exploration of the estuary ecosystem of the contaminated dam was accomplished through isolation, selection and characterization of the isolates obtained. The result of this study found superior SRB named DPS 1711, DPS 1705 and DPS 1703. The bacteria have the ability to grow at pH 3, room temperature and uses compost as organic substrate. This ability is an important factor for the application of isolates in the treatment of acid mine waste. Isolates have optimum optical density under the pH range of 4 to 7 and the best at pH 5 have a growth rate profile at a temperature range of 25 to 40&deg;C. The isolates observed were Gram-negative stem, motile bacteria which only grow in anaerobic condition. Physiological-biochemical characterization showed the three isolates, namely DPS 1703, DPS 1705 and DPS 1711 were SRB groups identified as Desulfotomaculum orientis. Key words: Sulfate reducing bacteria, polluted waters, estuary dam ecosystem. &nbsp;
Domaine de référence : Biocorrosion
Auteur W Budiarsa Suyasa, Suprihatin Iryanti E., A Dwi Adi Suastuti G., A Sri Kunti Pancadewi G.
Année de parution : 2018.
Type de document : Article de revue.
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Natural Biocides for Mitigation of Sulphate Reducing Bacteria

Résumé : This study addresses the potential usage of various herbaceous plants extract including betel leave extract (BLE), green tea (GTE), turmeric (TE), belalai gajah (BGE), garlic extracts (GE), and manjakani extracts (ME) as future biocides of SRB that are natural and nontoxic. Study revealed that retardation of growth was obtained after addition of 5mL of natural biocides to 100 mL of the culture. Reduced biomass growth was observed with most of the tested biocides, dictated by lower biomass contents accepts for ginger and garlic. The planktonic growth was successively suppressed with addition of GTE, TE, and BGE, where the biomass production was decreased by more than 80.0% compared to the control experiments. GRE increased the growth of planktonic bacteria while the GE induced the formation of biofilms, showed by increase in biomass productions with over 23.4% and 77.46% enhancements, respectively. These results suggest that turmeric, green tea, and belalai gajah plants extracts are highly potential biocidal agents for mitigating SRB, thus controlling the effect of MIC on metal surfaces. However, the chemical stability, potential toxicity, and consistent performance of the extracts need further investigation for optimization of its use on a real field scale.
Domaine de référence : Biocorrosion
Auteur Zain Md, Salwanis Wan, Salleh Hairul, Insyirah Nor, Abdullah A.
Année de parution : 2018.
Type de document : Page Web.
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Impact of Fe(II) oxidation in the presence of iron-reducing bacteria on subsequent Fe(III) bio-reduction

Résumé : The interplay of Fe(II) oxidation and Fe(III) bio-reduction occurs widely in both natural and engineered redox-dynamic systems. This study aimed to unravel the impact of Fe(II) oxidation by O2 in the presence of iron-reducing bacteria on subsequent Fe(III) bio-reduction. Mixed solutions of Fe2+ (0.1–0.5 mM) and Shewanella oneidensis strain MR-1 (MR-1, 2.0 × 107 CFU/mL) at neutral pH were first exposed to laboratory air for Fe(II) oxidation and bacterial inactivation, and then the resultant Fe(III) suspensions were switched to anoxic conditions for bio-reduction by the surviving bacteria. In the oxidation step, the coexisting MR-1 was inactivated by 0.8–1.71 orders of magnitude within 60 min. In the subsequent bio-reduction step, the resultant Fe(III) was bio-reduced by the surviving MR-1. Bio-reduction of the resultant Fe(III) by the surviving MR-1 was 1.8–2.5 times faster than that of the Fe(III) that was produced from Fe2+ oxidation without MR-1 by fresh MR-1 cells at 2.0 × 107 CFU/mL. Although MR-1 inactivation during Fe(II) oxidation may inhibit Fe(III) bio-reduction, the increase in bio-availability of the resultant Fe(III) and the residual reactivity of dead cells led to net enhancement of bio-reduction under the tested conditions. Lepidocrocite was the sole Fe(III) mineral that was produced from Fe2+ oxidation without MR-1, while 19% ferrihydrite was produced from Fe2+ oxidation in the presence of MR-1. The formation of low-crystallinity ferrihydrite accounts for the increase in bio-availability of the Fe(III) minerals. The findings of this study highlight an important but overlooked impact underlying the interplay of Fe(II) oxidation and Fe(III) bio-reduction.
Domaine de référence : Biocorrosion
Auteur Chen Rong, Liu Hui, Tong Man, Zhao Lei, Zhang Peng, Liu Deng, Yuan Songhu
Année de parution : 2018.
Mots-clés : Bio-availability, Ferrous iron, Iron cycling, Iron-reducing bacteria, Oxidation.
Type de document : Article de revue.
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WITHDRAWN : Can electrochemically active biofilm protect stainless steel used as electrodes in bioelectrochemical systems in a similar way as galvanic corrosion protection ?

Résumé : This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal
Domaine de référence : Biocorrosion
Auteur Shamsuddin Raba'atun Adawiyah, Bakar Mimi Hani Abu, Wan Daud Wan Ramli, Kim Byung Hong, Jahim Jamaliah Mat
Année de parution : 2018.
Type de document : Article de revue.
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Microbial corrosion resistance of a novel Cu-bearing pipeline steel

Résumé : Microbiologically influenced corrosion (MIC) is becoming a serious problem for buried pipelines. Developing environmentally friendly strategies for MIC control is increasingly urgent in oil/gas pipeline industry. Copper (Cu) in steels can not only provide aging precipitation strengthening, but also kill bacterium, offering a special biofunction to steels. Based on the chemical composition of traditional X80 pipeline steel, two Cu-bearing pipeline steels (1% Cu and 2% Cu) were fabricated in this study. The microstructure, mechanical properties and antibacterial property against sulphate-reducing bacteria (SRB) and Pseudomonas aeruginosa (P. aeruginosa) were studied. It was found that the novel pipeline steel alloyed by 1%Cu exhibited acicular ferrite microstructure with nano-sized Cu-rich precipitates distribution in the matrix, resulting in better mechanical properties than the traditional X80 steel, and showed good MIC resistance as well. The pitting corrosion resistance of 1% Cu steel in as-aged condition was significantly better than that of X80 steel. A possible antibacterial mechanism of the Cu-bearing pipeline steel was proposed.
Domaine de référence : Biocorrosion
Auteur Shi Xianbo, Yan Wei, Xu Dake, Yan Maocheng, Yang Chunguang, Shan Yiyin, Yang Ke
Année de parution : 2018.
Mots-clés : Cu alloying, Cu-rich nano-precipitation, Microbiologically influenced corrosion, Pipeline steel, Pitting corrosion.
Type de document : Article de revue.
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The effect of environmental variables on early corrosion of high–strength low–alloy mooring steel immersed in seawater

Résumé : Traditionally, the designing of mooring lines has been aimed at fulfilling the mechanical strength criteria using standard theoretical models and simulation in wave tunnels. This approach has led to various critical failures since degradation of a mooring line under specific environmental and loading conditions, which depend on the locations of the off-shore platforms, were not properly considered. The purpose of this paper is to investigate into the effect of three environmental variables – temperature, salinity and dissolved oxygen – on the corrosion behaviour of two steel grades used for mooring chains and to develop an empirical model intended to link these variables with the corrosion rate. A full-factorial experiment was designed on the basis of the statistical analysis of the objective data on the ocean water conditions corresponding to nine regions of Atlantic, Indic and Arctic oceans. A practical uncoupled method to determine the corrosion rate of these steel grades as function of the water conditions was developed.
Domaine de référence : Biocorrosion
Auteur Nevshupa R., Martinez I., Ramos S., Arredondo A.
Année de parution : 2018.
Type de document : Article de revue.
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Microbial corrosion resistance of a novel Cu-bearing pipeline steel

Résumé : Microbiologically influenced corrosion (MIC) is becoming a serious problem for buried pipelines. Developing environmentally friendly strategies for MIC control is increasingly urgent in oil/gas pipeline industry. Copper (Cu) in steels can not only provide aging precipitation strengthening, but also kill bacterium, offering a special biofunction to steels. Based on the chemical composition of traditional X80 pipeline steel, two Cu-bearing pipeline steels (1% Cu and 2% Cu) were fabricated in this study. The microstructure, mechanical properties and antibacterial property against sulphate-reducing bacteria (SRB) and Pseudomonas aeruginosa (P. aeruginosa) were studied. It was found that the novel pipeline steel alloyed by 1%Cu exhibited acicular ferrite microstructure with nano-sized Cu-rich precipitates distribution in the matrix, resulting in better mechanical properties than the traditional X80 steel, and showed good MIC resistance as well. The pitting corrosion resistance of 1% Cu steel in as-aged condition was significantly better than that of X80 steel. A possible antibacterial mechanism of the Cu-bearing pipeline steel was proposed.
Domaine de référence : Biocorrosion
Auteur Shi Xianbo, Yan Wei, Xu Dake, Yan Maocheng, Yang Chunguang, Shan Yiyin, Yang Ke
Année de parution : 2018.
Mots-clés : Cu alloying, Cu-rich nano-precipitation, Microbiologically influenced corrosion, Pipeline steel, Pitting corrosion.
Type de document : Article de revue.
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A semi-continuous system for monitoring microbially influenced corrosion

Résumé : Microbially influenced corrosion (MIC), also known as biocorrosion, has significant impacts on the environment and economy. Typical systems to study biocorrosion are either dynamic (once-through flow) or static (serum bottle incubations). Dynamic systems can be materials and personnel intensive, while static systems quickly become nutrient limiting and exhibit long incubations. A semi-continuous biocorrosion cell was developed to address these issues. Low carbon shim steel was used as a test surface. Initial results revealed that 50 ppm glutaraldehyde (GLT), a common oil field biocide, in an abiotic cell was 3.6 times more corrosive (24.5 × 10−3 mm/y) than a biocorrosion cell inoculated with a sulfate-reducing bacteria (SRB) enrichment (6.73 × 10−3 mm/y). The SRB inoculated cell treated with GLT (50 ppm) reduced the corrosion rate from 6.73 × 10−3 mm/y to 3.68 × 10−3 mm/y. It was hypothesized that a biocide-surfactant combination would enhance biocide activity, thereby lowering corrosion in a semi-continuous biocorrosion cell. The biocide and surfactant were GLT (30 ppm) and Tween 80 (TW80; 100 ppm). MIC of SRB increased in the presence of a non-inhibitory concentration of GLT (23.4 × 10−3 mm/y), compared to the untreated +SRB condition (8.29 × 10−3 mm/y). The non-ionic surfactant alone reduced MIC (4.57 × 10−3 mm/y) and even more so in combination with GLT (3.69 × 10−3 mm/y). Over 50% of 16S rDNA sequences in the biofilm on the test surface were identified as belonging to the genera Desulfovibrio and Desulfomicrobium. The utility of a semi-continuous system for MIC studies and biocide testing was demonstrated. The concept of regular partial medium replacement is applicable to different corrosion cell and corrosion coupon geometries. Biocide-surfactant combinations may have the potential to reduce the concentration of biocides used in the field. In addition, a semi-defined medium for enumerating Acid-Producing Bacteria (APB) was developed, resulting in higher recoveries compared to a standard phenol red medium (e.g., 1.1 × 104 APB/cm2 vs &lt; 4 × 10−1 APB/cm2).
Domaine de référence : Biocorrosion
Auteur Eid Mary M., Duncan Kathleen E., Tanner Ralph S.
Année de parution : 2018.
Mots-clés : Acid-producing bacteria, Biocorrosion, Glutaraldehyde, Microbially influenced corrosion, Sulfate-reducing bacteria, Tween 80.
Type de document : Article de revue.
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An enhanced oil recovery polymer promoted microbial growth and accelerated microbiologically influenced corrosion against carbon steel

Résumé : Enhanced oil recovery typically relies on injection of seawater mixed with chemicals to increase reservoir pressure. A polymer such as partially hydrolyzed polyacrylamide (HPAM) is often added to increase viscosity. In this work, an oilfield biofilm consortium was found to utilize a commercial HPAM-based polymer. The polymer at 1000 ppm (w/w) promoted the growth of planktonic cells and sulfate reducing bacteria sessile cells in an artificial seawater medium during a 30-day incubation period in anaerobic vials. The polymer utilization led to 34.5% viscosity loss and more severe microbiologically influenced corrosion weight loss and pitting against C1018 carbon steel.
Domaine de référence : Biocorrosion
Auteur Jia Ru, Yang Dongqing, Abd Rahman Hasrizal Bin, Gu Tingyue
Année de parution : 2018.
Mots-clés : A. Carbon steel, B. SEM, B. Weight loss, B. XRD, C. Microbiological corrosion, C. Pitting corrosion.
Type de document : Article de revue.
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Metallurgical investigation of premature failures for 316L austenitic stainless steel pipes

Résumé : This thesis analyzed and investigated the premature failures of pipes made from type 316L austenitic stainless steels. Multiple leaks were observed in scattered locations of a piping network of around 10 km after only 4 months in service transferring ammonium sulfate solution. The initial investigation indicated that the piping network was constructed 3 years earlier. After the construction, the stainless steel pipes were hydrotested to ensure the joints integrity. However, the piping network was not properly drained and dried after the hydrotest which resulted in water stagnation for the complete idle period between construction and commissioning. Therefore, an electrochemical, chemical, mechanical and metallurgical testing and analyses were conducted to determine the damage mechanism which consequently caused these failures. I have conducted electrochemical tests on a 316L stainless steel electrode in chloridized ammonium sulfate solution to determine its corrosivity. The electrochemical tests showed that the corrosion rates of 316L SS in ammonium sulfate solution is very low. This conclusion was supported by other laboratory studies at higher temperature and by the industrial corrosion tables published online. Also, two spools from the piping network that experienced the failures were analyzed using stereoscope, optical microscope, scanning electron microscopy/energy dispersive spectrometry, X-ray fluorescence and carbon/sulfur analyzer, tensile testing and microhardness testing. The results of these tests indicated that the pipes were leaking at the 6 O’clock position near the weld and heat affected zone areas. The morphology of the attack illustrated a narrow opening with large sub-surface cavity and tunneling initiated from the internal surface of the pipes. The weld joints displayed weld defects in terms of root concavity and lack of penetration. The metallurgical investigation strongly suggests that the pipes failed due to Microbiologically Influenced Corrosion (MIC). During the idle period of 3 years, the stagnant untreated water in the closed system was an appropriate environment for bacterial growth leading to severe damage at the welding joints and the base metal.
Domaine de référence : Biocorrosion
Auteur Al Muaisub Mohammed
Année de parution : 2018.
Type de document : Thèse.
Source : University of British Columbia
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Chapter 6 - Corrosion and protection of the metallic structures in the petroleum industry due to corrosion and the techniques for protection

Résumé : Corrosion is affecting the metallic structures’ stability of the industry and putting at risk the safety of the employees and environment. This chapter emphasizes explaining the common types of corrosion damages that can be present in the oil and gas industry and details of the mechanism of material failure and the possible ways for protection. The petroleum industry is facing the deterioration of metal surfaces in their working environment due to the electrochemical process of corrosion. It’s one of the industries that is spending the most money of the total corrosion expenditure all over the world. Corrosion is an economical problem that must be addressed to provide a safer environment that prolongs the life of material, minimizing the risk of environmental issues and catastrophes. A good way to address this problem is by studying the characteristics of each of the corrosion problems and the best way to minimize or eliminate the reasons for corrosion.
Domaine de référence : Biocorrosion
Auteur Makhlouf Abdel Salam H., Herrera Victor, Muñoz Edgar
Année de parution : 2018.
Mots-clés : corrosion, galvanic series, metallic structures, oxidation–reduction, petroleum industry, pitting corrosion, transgranular cracking.
Type de document : Chapitre de livre.
Source : Butterworth-Heinemann
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Chapter 1 - Failure of the metallic structures due to microbiologically induced corrosion and the techniques for protection

Résumé : Microbiologically induced corrosion (MIC) is a corrosion type that is harmful to most engineering materials. MIC deteriorates the metal surface through the metabolic activity of microorganisms. Since the 19th century, scientists have been trying to explain the role of microorganisms in corrosion. The damage due to MIC is broken down into a three-step process: creation of biofilm, change of environment at the metal surface, and deterioration of the metal. The common bacteria associated with MIC are sulfate-reducing bacteria, acid-producing bacteria, and iron-reducing bacteria. The most common forms of corrosion influenced by MIC are pitting corrosion, crevice corrosion, and stress corrosion cracking. This chapter discusses the types of MIC, the mechanisms of corrosion damage due to MIC, the common methods used for detecting and monitoring MIC, and the methods of materials protection from MIC attack.
Domaine de référence : Biocorrosion
Auteur Makhlouf Abdel Salam H., Botello Martin A.
Année de parution : 2018.
Mots-clés : acid-producing bacteria, iron-reducing bacteria, materials failure, microbiologically induced corrosion, pitting corrosion, sulfate-reducing bacteria.
Type de document : Chapitre de livre.
Source : Butterworth-Heinemann
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Biofilm Formation and Corrosion on Carbon Steel API 5LX60 in Clayey Soil

Résumé : Corrosion of buried pipelines is a matter of concern to the oil and gas industry since the time when carbon steel began to be widely used in these pipelines for the transportation of fluids. The microbial communities associated with biofilms promote modification in the surrounding environment and may accentuate the degradation of oil and gas pipelines causing leaks or even accidents. This work aimed to evaluate corrosion and biofilm formation in carbon steel API 5LX60 coupons buried in clayey soil from an industrial region in north-eastern Brazil. The average corrosion rates were determined by gravimetric test and the quantification of bacteria and fungi were using the Most Probable Number (MPN) and Colony Forming Units (CFU) techniques respectively. The results showed a great influence of clayey soil on corrosion rates and time of adherence for microorganisms on metal surfaces.Keywords: biofilm; corrosion; pipelines; soil; microorganisms
Domaine de référence : Biocorrosion
Auteur Queiroz Germana Arruda de, Andrade Jéssica Simões, Malta Tiago Barros Santos, Vinhas Gloria, Lima Maria Alice Gomes de Andrade, Queiroz Germana Arruda de, Andrade Jéssica Simões, Malta Tiago Barros Santos, Vinhas Gloria, Lima Maria Alice Gomes de Andrade
Année de parution : 2018.
Type de document : Article de revue.
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Synergistic effect of sulphate-reducing bacteria and external tensile stress on the corrosion behaviour of 80 pipeline steel in neutral soil environment

Résumé : X80 pipeline steel, which has a wide application prospect, is easily affected by sulphate-reducing bacteria (SRB) in typical neutral soil and causes stress corrosion cracking. Using a self-made experimental device, the stress corrosion cracking behaviour and mechanism of X80 pipeline steel under the synergistic effects of SRB and tensile stress in Shenyang soil were investigated through the slow strain rate test, electrochemical impedance spectroscopy, potentiodynamic polarisation technology and scanning electron microscopy. In a growth cycle, results showed that SRB quantity initially increased, decreased and peaked on the eight day. SRB improved the stress corrosion cracking sensitivity of X80 steel. When the amount of SRB was 8.7 × 103 cell/mL to 1.6 × 104 cell/mL, ductile fracture occurred in X80 steel, and mechanical factors could accelerate different forms of anodic dissolution induced by different amounts of SRB. When the SRB quantity increased by 1.7 × 104 cell/mL, brittle fracture occurred in X80 steel. The fracture mechanisms were anodic dissolution and hydrogen-induced cracking.
Domaine de référence : Biocorrosion
Auteur Xie Fei, Li Xue, Wang Dan, Wu Ming, Sun Dongxu
Année de parution : 2018.
Mots-clés : Neutral soil, Stress corrosion cracking, Sulphate-reducing bacteria, X80 pipeline steel.
Type de document : Article de revue.
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Risk Based, Statistical Approach to Assessment of Corrosion Anomalies in Pipelines

Résumé : Abstract In-line inspection of subsea pipelines is a common method to detect anomalies within carbon steel pipelines however the cost of an intelligent pigging campaign is sometimes not economically viable, particularly for situations requiring subs
Domaine de référence : Biocorrosion
Auteur Scales Derek, Hubbard Rex, Merrick Chris
Année de parution : 2018.
Type de document : Article de colloque.
Source : Offshore Technology Conference
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Severe microbiologically influenced corrosion of S32654 super austenitic stainless steel by acid producing bacterium Acidithiobacillus caldus SM-1

Résumé : Microbiologically influenced corrosion (MIC) of S32654 (654SMO) super austenitic stainless steel (SASS) by acid producing bacterium (APB), Acidithiobacillus caldus SM-1, a strain of sulfur-oxidizing bacteria (SOB) used in biohydrometallurgy field, was investigated using electrochemical measurements and surface characterizations during a 14-day immersion test. The results indicated that S32654 SASS was susceptible to MIC by APB, and A. caldus SM-1 was capable of producing an aggressive acidic environment underneath the biofilm, resulting in the dissolution of the passive film and severe pitting attacks against S32654 SASS, which is commonly regarded as a corrosion resistant material.
Domaine de référence : Biocorrosion
Auteur Dong Yuqiao, Jiang Baota, Xu Dake, Jiang Chengying, Li Qi, Gu Tingyue
Année de parution : 2018.
Mots-clés : EIS, Microbiological corrosion, Pitting corrosion, S32654 super austenitic stainless steel.
Type de document : Article de revue.
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Effect of residual and external stress on corrosion behaviour of X80 pipeline steel in sulphate-reducing bacteria environment

Résumé : X80 pipeline steel has a wide application prospect. This steel is easily affected by sulphate-reducing bacteria (SRB) in neutral soil and causes stress-corrosion cracking. Based on the results of static and dynamic electrochemical tests, the corrosion behaviour and mechanism of X80 pipeline steel under the synergistic effect of stress and SRB in Shenyang soil environment were investigated through slow strain rate testing, electrochemical impedance spectroscopy, potentiodynamic polarisation technique and surface analysis techniques. Results showed that internal residual and external tensile stress accelerate the corrosion of X80 steel, and the effect of SRB is influenced by the stress type. When only residual stress is applied, the SRB adsorption film plays a certain protective role, which reduces the corrosion sensitivity of X80 steel, and its corrosion mechanism is the anode dissolution of the film rupture. When tensile stress is applied, stress and SRB play a role in the stress concentration at the crack tip, thereby increasing the corrosion sensitivity of X80 steel. The corrosion mechanism is then the activated anode dissolution.
Domaine de référence : Biocorrosion
Auteur Li Xue, Xie Fei, Wang Dan, Xu Changhao, Wu Ming, Sun Dongxu, Qi Jianjing
Année de parution : 2018.
Mots-clés : Corrosion, External stress, Residual stress, Sulphate-reducing bacteria, X80 pipeline steel.
Type de document : Article de revue.
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Détection et caractérisation spatiale de la corrosion localisée des aciers au carbone en milieu anaérobie sulfurogène

Résumé : La présence à la surface des aciers au carbone d'un biofilm développé en milieu anaérobie peut, dans certains cas, induire une attaque de corrosion localisée. Dans le cadre d'une meilleure compréhension de cette biocorrosion, une nouvelle technique électrochimique, développée en collaboration entre IFREMER et le Laboratoire de Physique des Liquides et d'Electrochimie, est présentée. Destinée à l'étude de l'aspect local de ce type de phénomène, la technique décrite permet d'établir une cartographie de densité de courant sur une surface métallique et d'identifier les zones jouant un rôle anodique et celles jouant un rôle cathodique. Pour cela, une sonde de mesure constituée de deux micro-électrodes est positionnée au voisina­ ge de la surface du substrat et la différence de potentiel entre ces deux électrodes est mesurée, permettant d'accéder à la valeur de la chute ohmique dans la solution et, par conséquent, à celle du courant local. Le balayage de la surface étudiée permet de visualiser la répartition des cou­ rants locaux et ainsi détecter et caractériser les attaques de corrosion localisée: étendue de la zone anodique et densité de courant. Suite à la présentation de la technique et de la procédure de mise au point, un phénomène de biocorrosion amorcée mécaniquement sur un coupon métal­ lique est analysé par tracé de cartographies successives, y compris l'évaluation de l'efficacité d'un biocide.
Domaine de référence : Biocorrosion
Auteur Festy Dominique, Forest B., Keddam Michel, Marchal R., Moros Nicolas Monfort, Tribollet Bernard
Année de parution : 2018.
Type de document : Article de revue.
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Methods for Preventing Microbial Growth and Microbiologically Influenced Corrosion in a Biodegradable and/or Renewable Fuel, Hydraulic Fluid and/or Lubricant

Résumé : Fuels, hydraulic fluids and lubricants made of or comprising a portion of renewable hydrocarbon raw materials, as well as biodegradable fuels, hydraulic fluids and lubricants are known to support microbial growth. Highly toxicorganic biocides have been added to reduce microbial growth. The use of such biocides can now be avoided, by instead using a stable solution of boric acid in a solvent, the boric acid being completely dissolved or at least free from any particles larger than 100 nm in size, and adding this solution to the fuel, hydraulic fluid or lubricant to give a final concentration of boron in the range of 1-100 ppm, preferably 1 -50 ppm in the product. While preventing microbial growth, the addition of boron also reduces corrosion, in particular microbiologically induced corrosion (MIC).
Domaine de référence : Biocorrosion
Auteur UNDÉN Magnus, FIELD Ian, NILSSON Kristina
Année de parution : 2018.
Type de document : Brevet.
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Plus de références Biocorrosion


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Study on Assessment Approach of Antimicrobial and Antifouling Performance for Marine Antifouling Coating

Résumé : ABSTRACT The attachment of marine fouling organisms is harmful to any marine structure such as ship hulls, fishing nets, jetties and platforms. Marine antifouling coating is still the widely commercial used solution for marine antifouling in shippin
Domaine de référence : Antifouling
Auteur Bai Xiuqin, Chang Jiangfan, He Xiaoyan, Yuan Chengqing
Année de parution : 2018.
Type de document : Article de colloque.
Source : International Society of Offshore and Polar Engineers
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Benthic biodiversity on old platforms, young wind farms, and rocky reefs

Résumé : Abstract. The introduction of artificial hard substrates in an area dominated by a sandy seabed increases habitat available to epifouling organisms. To investi
Domaine de référence : Antifouling
Auteur Coolen Joop W. P., van der Weide Babeth, Cuperus Joël, Blomberg Maxime, Moorsel Van, M Godfried W. N., Faasse Marco A., Bos Oscar G., Degraer Steven, Lindeboom Han J.
Année de parution : 2018.
Type de document : Article de revue.
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Electrochemical (pre)treatments to prevent biofouling

Résumé : In order to prevent the formation of a biofilm on the surface of materials in an aqueous environment various strategies could be developed. Notably following an electrochemical route it is possible to apply a potential which could lead to (i) oxidation of halide anions leading to the formation of biocidal molecules, (ii) O2 reduction leading to H2O2, (iii) water reduction leading to H2 bubbles or (iv) a low-intensity electric potential. Moreover an electrochemical method could be used to nano or microstructure the material surface or to deposit on the material a coating which would avoid protein adsorption or microorganism attachment and therefore the formation of a biofilm, this coating could be of an inorganic or an organic film.
Domaine de référence : Antifouling
Auteur Debiemme-Chouvy Catherine, Cachet Hubert
Année de parution : 2018.
Type de document : Article de revue.
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Chapter 14 - Microbial Biofilms, Fouling, Corrosion, and Biodeterioration of Materials

Résumé : Biofilms and biofouling as important ecological phenomena have important implications affecting the development of invertebrates on surfaces in aquatic ecosystems, with economic impacts in several industries. Microbial biofilms on the surfaces of materials also affect the properties, longevity, and performance. The process of fouling and its prevention has been a major scientific challenge for many decades. Biofilms and fouling on surfaces affects the integrity of the substrutam materials from metals to inorganic and composites. Biodegradation and biodeterioration of materials are discussed here with information on relevant testing techniques tailored to material types. Biodeterioration by microorganisms is also discussed and prevention strategies offered to allow effective management of selective environmental conditions to ensure material integrity.
Domaine de référence : Antifouling
Auteur Gu Ji-Dong, Kutz Myer
Année de parution : 2018.
Mots-clés : biodeterioration, biofilms, Biofouling, composite materials, cultural heritage, metal corrosion, protection.
Type de document : Chapitre de livre.
Source : William Andrew Publishing
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Marine Biotechnology in Brazil : Recent developments and its potential for innovation

Résumé : Marine biotechnology is an emerging field in Brazil and includes the exploration of marine microbial products, aquaculture, omics, isolation of biologically active compounds, identification of biosynthetic gene clusters from symbiotic microorganisms, investigation of invertebrate diseases caused by potentially pathogenic marine microbes, and development of antifouling compounds. Furthermore, the field also encompasses description of new biological niches, current threats, preservation strategies as well as its biotechnological potential. Finally, it is important to depict some of the major approaches and tools being employed to such end. To address the challenges of marine biotechnology, the Brazilian government, through the Ministry of Science, Technology, Innovation, and Communication, has established the National Research Network in Marine Biotechnology (BiotecMar) (www.biotecmar.sage.coppe.ufrj.br). Its main objective is to harness marine biodiversity and develop the marine bioeconomy through innovative research.
Domaine de référence : Antifouling
Auteur Thompson Fabiano, Kruger Ricardo Henrique, Thompson Cristiane Carneiro, Berlinck Roberto G. S., Coutinho Ricardo, Landell Melissa Fontes, Pavao Mauro Sergio, Mourão Paulo Antonio De Souza, Salles Ana, Negri Naiane, Lopes Fabyano Alvares Cardoso, Freire Vítor Fernandes, Macedo Alexandre José, Maraschin Marcelo, Pérez Carlos Daniel, Pereira Renato Crespo, Radis-Baptista Gandhi, Rezende Rachel Passos, Valenti Wagner Cotroni, Abreu Paulo C., BioTecMar Network
Année de parution : 2018.
Mots-clés : Aquaculture, Bioprospecting, drugs, Microbes, omics.
Type de document : Article de revue.
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Biofilm monitoring as a tool to assess the efficiency of artificial reefs as substrates : Toward 3D printed reefs

Résumé : Habitat destruction is one of the main causes of the decline of biodiversity and of fishery resources in the marine environment. An artificial reef (AR) could be a tool for protecting or restoring these habitats and their declining biodiversity, and also help to enhance sustainable fisheries. The goal is to design non-polluting structures that best mimic the complexity of natural habitats in order to improve their service to the community. To date, the assessment of reef performance has been mostly focused on fish assemblages and species of ecological and/or socio-economic interest, and has disregarded the biofilm communities that determine the first level of an AR’s trophic network. In this work, we used biofilm formation to compare the quality of substrates used as building parts for an AR, in order to optimize an eco-friendly material that will be used to design a new generation of ARs produced by giant 3D printers. The structure of the photosynthetic communities has been identified using pigment biomarkers and their production of exudates has been analysed. These polymeric substances were quantified in terms of total sugar and protein concentrations. They were further analysed in terms of amino acid content. We found no significant differences between the micro-algae communities developed on the different substrates. These photosynthetic communities were mainly composed of diatoms, prasinophytes, haptophytes, and dinoflagellates. However, we showed that the material for ARs is crucial for biofilm development, especially with regard to its secretions of sugar. The choice of an appropriate substrate for AR construction is thus of particular importance since biofilm secretions determine the organic substrate on which sessile macro-organisms will settle.
Domaine de référence : Antifouling
Auteur Riera Elisabeth, Lamy Dominique, Goulard Christophe, Francour Patrice, Hubas Cédric
Année de parution : 2018.
Mots-clés : Artificial reef substrates, Bio-indicator, Biofilm, Extracellular polymeric substances, Photosynthetic pigments.
Type de document : Article de revue.
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Effect of CNT/PDMS Nanocomposites on the Dynamics of Pioneer Bacterial Communities in the Natural Biofilms of Seawater

Résumé : In this study, the antifouling (AF) performance of different carbon nanotubes (CNTs)-modified polydimethylsiloxane (PDMS) nanocomposites (PCs) was examined directly in the natural seawater, and further analyzed using the Multidimensional Scale Analyses (MDS) method. The early-adherent bacterial communities in the natural biofilms adhering to different PC surfaces were investigated using the single-stranded conformation polymorphism (SSCP) technique. The PCs demonstrated differences and reinforced AF properties in the field, and they were prone to clustering according to the discrepancies within different CNT fillers. Furthermore, most PC surfaces only demonstrated weak modulating effects on the biological colonization and successional process of the early bacterial communities in natural biofilms, indicating that the presence of the early colonized prokaryotic microbes would be one of the primary causes of colonization and deterioration of the PCs. C6 coating seems to be promising for marine AF applications, since it has a strong perturbation effect on pioneer prokaryotic colonization.
Domaine de référence : Antifouling
Auteur Ji Yubin, Sun Yuan, Lang Yanhe, Wang Lei, Liu Bing, Zhang Zhizhou
Année de parution : 2018.
Mots-clés : antifouling coatings, biofouling, multidimensional scale analysis, natural biofilms, polydimethylsiloxane, single-stranded conformation polymorphism.
Type de document : Article de revue.
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New Horizons in Marine Coatings

Résumé : Marine biofouling is an increasing problem from both economic and environmental points of view in terms of increased resistance, increased fuel consumption, increased GHG emissions and transportation of harmful non-indigenous species. Marine coatings are prevalently used to mitigate biofouling and smooth the surfaces of hulls. This paper aims at introducing new horizons and novel approaches in marine antifouling coatings. Firstly, marine biofouling and fouling prevention methods are briefly introduced. Afterwards, latest research in coating/fouling hydrodynamics is presented. Biomimetic approach to antifouling technology, bio-inspired antifouling strategies and the challenges in designing bio-inspired antifouling coatings are then discussed in detail. It is believed that, the on-going research in marine coatings will lead to an effective mitigation of marine biofouling while maintaining the harmony between man-made structures and marine life.
Domaine de référence : Antifouling
Auteur Demirel Yigit Kemal
Année de parution : 2018.
Type de document : Article de revue.
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Drag-reducing riblets with fouling-release properties : development and testing

Résumé : The manufacture and preliminary testing of a drag-reducing riblet texture with fouling-control properties is presented. The commercial fouling-release product Intersleek® 1100SR was modified to manufacture riblet-textured coatings with an embossing technology. Hydrodynamic drag measurements in a Taylor–Couette set-up showed that the modified Intersleek® riblets reduced drag by up to 6% compared to a smooth surface. Barnacle settlement assays demonstrated that the riblets did not substantially reduce the ability of Intersleek® 1100SR to prevent fouling by cyprids of Balanus amphitrite. Diatom adhesion tests revealed significantly higher diatom attachment on the riblet surface compared to smooth Intersleek® 1100SR. However, after exposure to flow, the final cell density was similar to the smooth surface. Statically immersed panels in natural seawater showed an increase of biofilm cover due to the riblets. However, the release of semi-natural biofilms grown in a multi-species biofilm culturing reactor was largely unaffected by the presence of a riblet texture.
Domaine de référence : Antifouling
Auteur Benschop H. O. G., Guerin A. J., Brinkmann A., Dale M. L., Finnie A. A., Breugem W.-P., Clare A. S., Stübing D., Price C., Reynolds K. J.
Année de parution : 2018.
Mots-clés : antifouling, biofilm release, drag reduction, Intersleek®, marine coatings, Riblet texture.
Type de document : Article de revue.
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Hydrosound Marine Anti-Fouling System

Résumé : A hydrosound marine anti-fouling system with a microcontroller monitoring and modifying, as desired, hydrosound pulse rate, output frequencies and volume level. This allows hydrosound pulse rate, output frequency and volume to be adjusted to levels determined to be effective with local marine growth. By adding a sensor to monitor hydrosound pulse rate, output frequencies and volume, an automatic testing process can be instituted at timed intervals and monitored by the microcontroller to confirm the hydrosound marine anti-fouling system is fully functioning.
Domaine de référence : Antifouling
Auteur TASKER Trevor, KNOX Derek
Année de parution : 2018.
Type de document : Brevet.
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Effect of Surface Hydration on Antifouling Properties of Mixed Charged Polymers

Résumé : Interfacial water structure on a polymer surface in water (or surface hydration) is related to the antifouling activity of the polymer. Zwitterionic polymer materials exhibit excellent antifouling activity due to their strong surface hydration. It was proposed to replace zwitterionic polymers using mixed charged polymers because it is much easier to prepare mixed charged polymer samples with much lower costs. In this study, using sum frequency generation (SFG) vibrational spectroscopy, we investigated interfacial water structures on mixed charged polymer surfaces in water, and how such structures change while exposing to salt solutions and protein solutions. The 1:1 mixed charged polymer exhibits excellent antifouling property while other mixed charged polymers with different ratios of the positive/negative charges do not. It was found that on the 1:1 mixed charged polymer surface, SFG water signal is dominated by the contribution of the strongly hydrogen bonded water molecules, indicating strong hydration of the polymer surface. The responses of the 1:1 mixed charged polymer surface to salt solutions are similar to those of zwitterionic polymers. Interestingly, exposure to high concentrations of salt solutions leads to stronger hydration of the 1:1 mixed charged polymer surface after replacing the salt solution with water. Protein molecules do not substantially perturb the interfacial water structure on the 1:1 mixed charged polymer surface and do not adsorb to the surface, showing that this mixed charged polymer is an excellent antifouling material.
Domaine de référence : Antifouling
Auteur Leng Chuan, Huang Hao, Zhang Kexin, Hung Hsiang-Chieh, Xu Yao, Li Yaoxin, Jiang Shaoyi, Chen Zhan
Année de parution : 2018.
Type de document : Article de revue.
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Antifouling coating compositions, antifouling coating films, antifouling substrates, methods for producing antifouling substrates, and methods of storing antifouling coating compositions

Résumé : An antifouling coating composition contains a silyl ester (co)polymer and medetomidine and is used to prevent the fouling of substrates by aquatic organisms and which can form antifouling coating films exhibiting outstanding antifouling properties over a long period and also has good storage stability. The antifouling coating composition includes a silyl ester (co)polymer (A) and medetomidine (B), the silyl ester (co)polymer (A) including structural units derived from a monomer (a) represented by the general formula (I): R1—CH═C(CH3)—COO—(SiR2R3O)n—SiR4R5R6, and structural units derived from an unsaturated monomer (b) copolymerizable with the monomer (a).
Domaine de référence : Antifouling
Auteur Iwata Yuki, TANINO Soichiro, Masuda Satoshi, Tanaka Hideyuki
Année de parution : 2018.
Mots-clés : antifouling, coating, composition, ester, silyl.
Type de document : Brevet.
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The anti-biofouling behavior of high voltage pulse electric field (HPEF) mediated by carbon fiber composite coating in seawater

Résumé : One of the most important research areas in the marine industry is to investigate new and effective anti-biofouling technologies. In this study, high voltage pulse electric field (HPEF) mediated by carbon fiber (CF) composite coating was utilized to prevent the fouling of bacteria, microalgae and barnacle larvae in seawater. The plate count, 2, 3, 5-triphenyl-tetrazolium chloride (TTC) reduction assay and neutral red (NR) staining and larval motility detection showed that the inactivation rates were at the highest levels, which reached 99.1%, 99.9%, 99.7%, 98.7% and 85% respectively for Pseudomonas sp., Vibrio sp., iron bacteria, Navicula sp. and the second stage nauplii of Balanus reticulatus, under the HPEF with 19 kV pulse amplitude, 23.15 kHz frequency and 0.5 duty cycle. The field-emission scanning electron microscopy (FE-SEM) of Navicula sp. revealed that the HPEF brought about the cell lysis and the cell organic matter release on the coating, which could be the mechanism of the inactivation by the HPEF. Additionally, the FE-SEM and Raman spectroscopy indicated that the HPEF hardly damaged the coating.
Domaine de référence : Antifouling
Auteur Feng Tiantian, Wu Jinyi, Chai Ke, Yang Pengpeng
Année de parution : 2018.
Mots-clés : Anti-biofouling, Cell lysis, Composite coating, High voltage pulse electric field.
Type de document : Article de revue.
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Reduction of bacterial biofilm formation using marine natural antimicrobial peptides

Résumé : There is an important need for the development of new “environmentally-friendly” antifouling molecules to replace toxic chemicals actually used to fight against marine biofouling. Marine biomass is a promising source of non-toxic antifouling products such as natural antimicrobial peptides produced by marine organisms. The aim of this study was to demonstrate the efficiency of antimicrobial peptides extracted from snow crab (SCAMPs) to reduce the formation of marine biofilms on immerged mild steel surfaces. Five antimicrobial peptides were found in the snow crab hydrolysate fraction used in this study. SCAMPs were demonstrated to interact with natural organic matter (NOM) during the formation of the conditioning film and to limit the marine biofilm development in terms of viability and bacterial structure. Natural SCAMPs could be considered as a potential alternative and non-toxic product to reduce biofouling, and as a consequence microbial induced corrosion on immerged surfaces.
Domaine de référence : Antifouling
Auteur Doiron K., Beaulieu L., St-Louis R., Lemarchand K.
Année de parution : 2018.
Mots-clés : Antifouling, Antimicrobial peptides, Bacterial diversity, Conditioning film, Marine biofilm.
Type de document : Article de revue.
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In-Field Applicable Coatings for Corrosion and Biofouling Control in Marine Environments

Résumé : Abstract Corrosion and biofouling control is an important consideration for offshore oil structures. Corrosion rates for steel exposed to seawater immersion and brine air can easily exceed 10 mils per year if left unprotected in the splash zone, whi
Domaine de référence : Antifouling
Auteur Nakatsuka Matthew, Thapa Sumil, Brown Erika, Veedu Vinod, Santalucia Andy
Année de parution : 2018.
Type de document : Article de colloque.
Source : Offshore Technology Conference
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Antifouling Properties of a Self-Assembling Glutamic Acid-Lysine Zwitterionic Polymer Surface Coating

Résumé : There is a need for the development of antifouling materials to resist adsorption of biomacromolecules. Here we describe the preparation of a novel zwitterionic block copolymer with the potential to prevent or delay the formation of microbial biofilms. The block copolymer comprised a zwitterionic (hydrophilic) section of alternating glutamic acid (negatively charged) and lysine (positively charged) units and a hydrophobic polystyrene section. Cryo-TEM and dynamic-light-scattering (DLS) results showed that, on average, the block copolymer self-assembled into 7-nm-diameter micelles in aqueous solutions (0 to 100 mM NaCl, pH 6). Quartz crystal microbalance with dissipation monitoring (QCM-D), atomic force microscopy (AFM), and contact angle measurements demonstrated that the block copolymer self-assembled into a brush-like monolayer on polystyrene surfaces. The brush-like monolayer produced from a 100 mg/L block copolymer solution exhibited an average distance, d, of approximately 4–8 nm between each block copolymer molecule (center to center). Once the brush-like monolayer self-assembled, it reduced EPS adsorption onto the polystyrene surface by ∼70% (mass), reduced the rate of bacterial attachment by >80%, and inhibited the development of thick biofilms. QCM-D results revealed that the EPS molecules penetrate between the chains of the brush and adsorb onto the polystyrene surface. Additionally, AFM analyses showed that the brush-like monolayer prevents the adhesion of large (>d) hydrophilic colloids onto the surface via hydration repulsion; however, molecules or colloids small enough to fit between the brush polymers (
Domaine de référence : Antifouling
Auteur Ziemba Christopher, Khavkin Maria, Priftis Dimitris, Acar Handan, Mao Jun, Benami Maya, Gottlieb Moshe, Tirrell Matthew, Kaufman Yair, Herzberg Moshe
Année de parution : 2018.
Type de document : Article de revue.
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Mini-Review : Antifouling Natural Products from Marine Microorganisms and Their Synthetic Analogs

Résumé : Biofouling causes huge economic loss and generates serious ecological issues worldwide. Marine coatings incorporated with antifouling (AF) compounds are the most common practices to prevent biofouling. With a ban of organotins and an increase in the restrictions regarding the use of other AF alternatives, exploring effective and environmentally friendly AF compounds has become an urgent demand for marine coating industries. Marine microorganisms, which have the largest biodiversity, represent a rich and important source of bioactive compounds and have many medical and industrial applications. This review summarizes 89 natural products from marine microorganisms and 13 of their synthetic analogs with AF EC50 values ≤ 25 μg/mL from 1995 (the first report about marine microorganism-derived AF compounds) to April 2017. Some compounds with the EC50 values < 5 μg/mL and LC50/EC50 ratios > 50 are highlighted as potential AF compounds, and the preliminary analysis of structure-relationship (SAR) of these compounds is also discussed briefly. In the last part, current challenges and future research perspectives are proposed based on opinions from many previous reviews. To provide clear guidance for the readers, the AF compounds from microorganisms and their synthetic analogs in this review are categorized into ten types, including fatty acids, lactones, terpenes, steroids, benzenoids, phenyl ethers, polyketides, alkaloids, nucleosides and peptides. In addition to the major AF compounds which targets macro-foulers, this review also includes compounds with antibiofilm activity since micro-foulers also contribute significantly to the biofouling communities.
Domaine de référence : Antifouling
Auteur Wang Kai-Ling, Wu Ze-Hong, Wang Yu, Wang Chang-Yun, Xu Ying
Année de parution : 2017.
Mots-clés : antifouling, Aquatic Organisms, Biofouling, Biological Products, Marine Biology, Structure-Activity Relationship.
Type de document : Article de revue.
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Comparative study of biofilm formation on biocidal antifouling and fouling-release coatings using next-generation DNA sequencing

Résumé : The bacterial and eukaryotic communities forming biofilms on six different antifouling coatings, three biocidal and three fouling-release, on boards statically submerged in a marine environment were studied using next-generation sequencing. Sequenced amplicons of bacterial 16S ribosomal DNA and eukaryotic ribosomal DNA internal transcribed spacer were assigned taxonomy by comparison to reference databases and relative abundances were calculated. Differences in species composition, bacterial and eukaryotic, and relative abundance were observed between the biofilms on the various coatings; the main difference was between coating type, biocidal compared to fouling-release. Species composition and relative abundance also changed through time. Thus, it was possible to group replicate samples by coating and time point, indicating that there are fundamental and reproducible differences in biofilms assemblages. The routine use of next-generation sequencing to assess biofilm formation will allow evaluation of the efficacy of various commercial coatings and the identification of targets for novel formulations.
Domaine de référence : Antifouling
Auteur Winfield Mark O., Downer Adrian, Longyear Jennifer, Dale Marie, Barker Gary L. A.
Année de parution : 2018.
Mots-clés : 16S, biocidal antifouling, Biofilms, fouling-release, ITS, next-generation sequencing.
Type de document : Article de revue.
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Experimental study of fouling process and antifouling effect in convective heat transfer under ultrasonic treatment

Résumé : An experimental study was carried out by a dynamic fouling monitor system to investigate the fouling process in convective heat transfer by ultrasonic treatment. During the experiment, the cooling water in heat exchanger was used as working fluid with the inlet temperature of 22.5 °C and 44 °C and the initial hardness of 300 mg/L and 500 mg/L, respectively. For all cases the inlet temperature of hot water was kept at 70°C, and the flowrates of cooling water and hot water were set at 0.77 m3/h and 0.81 m3/h, respectively. In this experimental setup, a double-tube heat exchanger was served as a test section of heat transfer, in which hot water flows inside the inner copper tube and cooling water flows in the annular gap between the two tubes, thus forming a counter-flow situation. Further, an ultrasonic device was installed for water treatment with a frequency of 20.7 kHz and power ranging from 0 to 75 W. The results showed that the fouling resistance for hard water increased evidently with increasing of water temperature and hardness. With the ultrasonic treatment, the fouling resistance decreased remarkably compared with the untreated case, and the asymptotic fouling resistance decreased monotonously with increasing of the ultrasonic power. Subsequently, the crystal morphology of calcium carbonate was observed in microscopic view and the transform of crystal from the vaterite to aragonite and calcite was analyzed based on the theory of the formation energy. It was confirmed that the ultrasonic treatment may have significant effect on the crystal shape, and more aragonites appeared with increasing powers of ultrasound.
Domaine de référence : Antifouling
Auteur Hou Tengfei, Chen Yongchang, Wang Zepeng, Ma Chongfang
Année de parution : 2018.
Mots-clés : convective heat transfer, crystal morphology, fouling resistance, ultrasonic treatment.
Type de document : Article de revue.
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Antifouling materials

Résumé : The invention provided herein presents a novel family of antifouling agents based on hydroxylated and fluorinated compounds.
Domaine de référence : Antifouling
Année de parution : 2017.
Type de document : Brevet.
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Antifouling, fouling release and antimicrobial materials for surface modification of reverse osmosis and nanofiltration membranes

Résumé : Membrane fouling, which arises from the nonspecific interaction between the membrane surface and foulants, significantly impedes the efficient application of membrane technology. Antifouling and antimicrobial materials are important classes of functional materials for the surface modification of reverse osmosis and nanofiltration membranes. Applications of various organic and inorganic materials having different characteristics such as size, surface charge, hydrophilicity, functionality and biocidal activity, provide protective/sacrificial layers to the membrane surface against different foulants and microorganisms. This review summarizes the properties and applications of organic and inorganic materials, antifouling mechanisms, and surface modification of pre-formed membranes. Materials such as zwitterionic polymers, neutral polymers, polyelectrolytes, amphiphilic polymers, quaternary ammonium polymers, biopolymers, hydrophilic polymers, polydopamine, inorganic salts, and nanomaterials have shown great potential in reducing foulant adhesion and/or proliferative microbial growth on membrane surfaces.
Domaine de référence : Antifouling
Auteur Choudhury Rikarani R., Gohil Jaydevsinh M., Mohanty Smita, Nayak Sanjay K.
Année de parution : 2018.
Type de document : Article de revue.
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Anti-biofouling superhydrophobic surface fabricated by picosecond laser texturing of stainless steel

Résumé : Anti-biofouling technology is based on specifically designed materials and coatings. This is an enduring goal in the maritime industries, such as shipping, offshore oil exploration, and aquaculture. Recently, research of the relationship between wettability and antifouling effectiveness has attracted considerable attention, due to the anti-biofouling properties of the lotus leaf and shark skin. In this study, super-hydrophobic surfaces (SHSs) with controllable periodic structures were fabricated on AISI304 stainless steel by a picosecond laser, and their anti-biofouling performance were investigated by seawater immersion for five weeks in summertime. The results showed that the specimens with SHS demonstrate significant anti-biofouling effect as compared with the bare stainless steel plate. We observed that nearly 50% decrease of the average microbe attachment area ratio (Avg. MAAR) could be obtained. The micro-groove SHS with more abundant hierarchical micro-nano structures showed better anti-biofouling performance than the micro-pit SHS.
Domaine de référence : Antifouling
Auteur Sun Ke, Yang Huan, Xue Wei, He An, Zhu Dehua, Liu Wenwen, Adeyemi Kenneth, Cao Yu
Année de parution : 2018.
Mots-clés : Anti-biofouling, Laser ablation, Laser induced surface hierarchical micro-nano structures, Stainless steel, Superhydrophobic surface.
Type de document : Article de revue.
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Biocidal Microcapsules for Biofouling Control

Résumé : The present invention is directed to bioactive microcapsules and to the process for their production. More in particular, the present invention relates to the production of bioactive microcapsules, or porous microspheres by a water-in-oil (W/O) microemulsion method combined with interfacial polymerization, involving the full or partial covalent immobilization of biocides and/or modified biocides within the microcapsules shell, or porous microspheres. In addition, the present invention further relates to the use of said bioactive microcapsules/microspheres for controlled release of biocides in antifouling application and their incorporation in matrices such as marine coatings.
Domaine de référence : Antifouling
Auteur MARQUES Ana Clara Lopes, GERALDES Elisabete Ribeiro Silva, BORDADO Joao Carlos Moura
Année de parution : 2018.
Type de document : Brevet.
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Hydrophobicity and Superhydrophobicity in Fouling Prevention in Sea Environment

Résumé : Abstract This chapter contains sections titled: Introduction Antifouling Options Problem Statement Coatings with Special Wettability and Performance Against Biofouling General Discussion Summary
Domaine de référence : Antifouling
Auteur Ferrari Michele, Cirisano Francesca
Année de parution : 2018.
Mots-clés : coatings, fouling control, marine environment, seawater, Superhydrophobic surface, wetting.
Type de document : Article de revue.
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Biodegradable Polymer with Hydrolysis-Induced Zwitterions for Antibiofouling

Résumé : Persistent protein resistance is critical for marine antibiofouling. We have prepared copolymer of 2-methylene-1,3-dioxepane (MDO), tertiary carboxybetaine ester (TCB), and 7-methacryloyloxy-4-methylcoumarin (MAMC) via radical ring-opening polymerization, where MDO, TCB, and MAMC make the polymer degradable, protein resistible, and photo-cross-linkable, respectively. Our study shows that the polymer can well adhere to the substrate with controlled degradation and water adsorption rate in artificial seawater (ASW). Particularly, the polymer film can generate zwitterions via surface hydrolysis in ASW. Quartz crystal microbalance with dissipation measurements reveal that such hydrolysis-induced zwitterionic surface can effectively resist nonspecific protein adsorption. Moreover, the surface can inhibit the adhesion of marine bacteria Pseudomonas sp. and Vibrio alginolyticus as well as clinical bacterium Escherichia coli.
Domaine de référence : Antifouling
Auteur Xie Qingyi, Xie Qianni, Pan Jiansen, Ma Chunfeng, Zhang Guangzhao
Année de parution : 2018.
Type de document : Article de revue.
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Hydrophilic Self-Replenishing Coatings with Long-Term Water Stability for Anti-Fouling Applications

Résumé : Hydrophilic coatings have recently emerged as a new approach to avoid the adhesion of (bio)organisms on surfaces immersed in water. In these coatings the hydrophilic character is crucial for the anti-fouling (AF) performance. However, this property can be rapidly lost due to the inevitable damages which occur at the surface, reducing the long-term effectiveness of the AF functionality. We report hydrophilic polycarbonate-mPEG polyurethane coatings with tunable hydrophilic properties as well as an excellent and long-term stability in water. The coatings exhibit low protein adhesion values and are able to self-replenish their hydrophilicity after damage, due to the existence of a reservoir of hydrophilic dangling chains incorporated in the bulk. The combination of low Tg and sufficient mobility of the mPEG dangling chains (enabled by chains with higher molecular weight) proved to be crucial to ensure autonomous surface hydrophilicity recovery when the coatings were immersed in water. This coatings and design approach offer new possibilities towards high performance AF coatings with an extended service life-time which can be used in several major applications areas, such as marine and biomedical coatings, with major economic and environmental benefits.
Domaine de référence : Antifouling
Auteur Jiménez-Pardo Isabel, Ven Leendert G. J. van der, Benthem Rolf A. T. M. van, With Gijsbertus de, Esteves A. Catarina C.
Année de parution : 2018.
Type de document : Article de revue.
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Bioinspired fish-scale-like stainless steel surfaces with robust underwater anti-crude-oil-fouling and self-cleaning properties

Résumé : Stainless steel (SS) have been widely used in marine structures and food industry due to its high corrosion resistance and excellent mechanical strength. Marine structures such as ships, ocean engineering and offshore rigs, are easily attacked by crude oil generated by oil spills and SS vessels applied in food industry are fouled by the organic matters in the fluid. Here, fish-scale-like SS surfaces with superhydrophilic and underwater superoleophobic property, including 316 L SS mesh and 304 SS plate, are designed by a facile chemical-based oxidation method. The obtained SS surfaces show excellent underwater anti-crude-oil-fouling property and thermal stability. Furthermore, the obtained 316 L SS mesh can effectively separate crude oil/water mixture solely driven by gravity. Significantly, the as-prepared SS surfaces possess robust antifouling and self-cleaning property during multiple cycles with the aid of Fenton-like catalytic reaction between Fe (III) and H2O2 or calcination at high temperature. Therefore, the fish-scale-like SS surfaces show great potential in a wide range of fields, such as marine antifouling, oil-water separation and food industry.
Domaine de référence : Antifouling
Auteur Peng Yubing, Wen Gang, Gou Xuelian, Guo Zhiguang
Année de parution : 2018.
Mots-clés : crude oil-water separation, marine anti-fouling, self-cleaning, stainless steel, superhydrophilic/underwater superoleophobic.
Type de document : Article de revue.
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A combined criterion of surface free energy and roughness to predict the wettability of non-ideal low-energy surfaces

Résumé : The significance of wettability between solid and liquid substances in different fields encourages scientists to develop accurate models to estimate the resultant apparent contact angles. Surface free energy (SFE), which is principally defined for ideal (flat) surfaces, is not applicable to predict the wettability of real (rough) surfaces. This paper introduces a new parameter, namely normalized surface free energy (NSFE) as a combination of SFE and roughness, to predict the contact angle of liquids on non-ideal low-energy surfaces. The remarkable consistency of the predicted and measured contact angles of liquids on some rough surfaces also confirm the validity of the approach.
Domaine de référence : Antifouling
Auteur Shaker Majid, Salahinejad Erfan
Année de parution : 2018.
Mots-clés : Roughness, Surface free energy, Wettability.
Type de document : Article de revue.
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Bacterial attachment and biofilm formation on stainless steel surface and their in vitro inhibition by marine fungal extracts

Résumé : This study evaluates anti-biofilm activity of four extracts from marine fungi; Penicillium citrinum PR1T4, Sarocladium strictum PP2L4, Aspergillus sydowii PR3T13, and Aspergillus spp. PR5T4 against Staphylococcus aureus, Listeria monocytogenes (ATCC 19115), Escherichia coli, and Salmonella typhi (ATCC 14028). The ability of bacterial cells to adhere, detach, and form biofilm on stainless steel surface were examined and ethyl acetate extract of the fungal culture (15 mg/ml) were tested for anti-biofilm activity for 3, 6, 9, 12, and 15 days. E. coli showed the highest ability to adhere (>8 log CFU/cm2) and lowest detachment (<4 log CFU/cm2) after 24, 48, and 72 hr. Extract PP2L4 had the highest anti-biofilm activity against S. typhi (1.70 ± 0.04 log CFU/cm2). Fungal extracts, bacteria, and incubation period were significant factors and their interactions were significant. The results showed that marine fungal extracts are important natural sources for anti-biofilm agents that have high potential as food-contact surface sanitizers. Practical applications Biofilm removal from food contact surfaces has been one of the greatest challenges for food industry. There have been efforts to explore natural agents with anti-biofilm properties. This study showed that marine-derived fungal extracts significantly reduced the number of attached cell on stainless steel discs and, therefore, is potential candidates for anti-biofilm agents. Special attention would be given to the fungal isolate (S. strictum PP2L4) that presented a promising activity against the gram-negative S. typhi. As the active fungal extracts were unable to completely remove the adhered bacterial cells, optimization is recommended to increase probability of isolating active compounds capable for complete biofilm removal. The active compounds could be used in sanitizer formulation and applied on various food-contact surfaces (e.g., stainless steel and plastic) at food related industries such as in institutional food service kitchens as well as home kitchens.
Domaine de référence : Antifouling
Auteur Mahyudin Nor Ainy, Mat Daud Noor Ifatul Hanim, Ab Rashid Nor-Khaizura Mahmud, Muhialdin Belal J., Saari Nazamid, Noordin Wan Norhana
Année de parution : 2018.
Type de document : Article de revue.
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Synthesis, antibacterial activity, and application in the antifouling marine coatings of novel acylamino compounds containing gramine groups

Résumé : Basing on the previous syntheses of ester compounds containing gramine functional groups, the researchers synthesized two novel acylamino compounds containing gramine groups and the structures of target compound were established using 1HNMR, 13CNMR, IR spectra, and elemental analysis. The antibacterial activity of the synthesized compounds against Escherichia coli and Staphylococcus aureus, as well as their antifouling activity were studied. The results showed that these compounds possessed high antibacterial activity and a minimal inhibitory concentration value of 0.03 mg/mL against bacteria. Moreover, their antifouling properties are superior to cuprous oxide and chlorothalonil, which are widely used as antifoulants. Furthermore, quantitative structure activity relationship studies with antibacterial activity of the nine gramine compounds were established. These provide theoretical and technical bases for preparing environment-friendly antifouling coatings with the compounds as antifouling agents.
Domaine de référence : Antifouling
Auteur Feng Kang, Li Xia, Yu Liangmin
Année de parution : 2018.
Mots-clés : Acylamino compounds, Antibacterial activity, Antifouling property, Gramine, Quantitative structure activity relationship.
Type de document : Article de revue.
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Anti-biofouling superhydrophobic surface fabricated by picosecond laser texturing of stainless steel

Résumé : Anti-biofouling technology is based on specifically designed materials and coatings. This is an enduring goal in the maritime industries, such as shipping, offshore oil exploration, and aquaculture. Recently, research of the relationship between wettability and antifouling effectiveness has attracted considerable attention, due to the anti-biofouling properties of the lotus leaf and shark skin. In this study, super-hydrophobic surfaces (SHSs) with controllable periodic structures were fabricated on AISI304 stainless steel by a picosecond laser, and their anti-biofouling performance were investigated by seawater immersion for five weeks in summertime. The results showed that the specimens with SHS demonstrate significant anti-biofouling effect as compared with the bare stainless steel plate. We observed that nearly 50% decrease of the average microbe attachment area ratio (Avg. MAAR) could be obtained. The micro-groove SHS with more abundant hierarchical micro-nano structures showed better anti-biofouling performance than the micro-pit SHS.
Domaine de référence : Antifouling
Auteur Sun Ke, Yang Huan, Xue Wei, He An, Zhu Dehua, Liu Wenwen, Adeyemi Kenneth, Cao Yu
Année de parution : 2018.
Mots-clés : Anti-biofouling, Laser ablation, Laser induced surface hierarchical micro-nano structures, Stainless steel, Superhydrophobic surface.
Type de document : Article de revue.
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Research progress of nano self - cleaning anti-fouling coatings

Résumé : There are many methods of evaluating the performance of nano self-cleaning anti-fouling coatings, such as carbon blacking method, coating reflection coefficient method, glass microbead method, film method, contact angle and rolling angle method, organic degradation method, and the application of performance evaluation method in self-cleaning antifouling coating. For the more, the types of nano self-cleaning anti-fouling coatings based on aqueous media was described, such as photocatalytic self-cleaning coatings, silicone coatings, organic fluorine coatings, fluorosilicone coatings, fluorocarbon coatings, polysilazane self-cleaning coatings. The research and application of different kinds of nano self-cleaning antifouling coatings are anlysised, and the latest research results are summed.
Domaine de référence : Antifouling
Auteur Liu Y., Zhao Y. J., Teng J. L., Wang J. H., Wu L. S., Zheng Y. L.
Année de parution : 2017.
Type de document : Article de revue.
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Novel composite graphene oxide/chitosan nanoplates incorporated into PES based nanofiltration membrane : Chromium removal and antifouling enhancement

Résumé : In this work, novel nanofiltration membranes with outstanding performance and antifouling properties were fabricated by incorporating composite graphene oxide/chitosan (GOC) nanoplates into the membrane structure. GOC composite nanoplates were prepared by surface modification of GO with chitosan. The GOC nanoplates were then introduced as additives in a polymeric phase in different concentrations (up to 1%) in view of membrane synthesis. these membranes were thoroughly characterized and assessed for their Na2SO4 and CrSO4 rejection and water flux. Furthermore, the antifouling performance of GO and GOC filled membranes in high concentration (1wt%) was investigated. Modified membranes with addition of GOCs showed a higher hydrophilicity, pure water flux and rejection, and a smoother surface compared to a bare PES and a GO incorporated membrane. SEM surface images indicated a more uniformed distribution of GOCs at a high loading rate (1wt%) compared to GO. Due to the uniform dispersion of GOCs, a better antifouling performance was observed than for GO filled membranes. The results indicate that surface modification of GO with chitosan can enhance the membrane performance and properties, due to availability of sites with higher activity.
Domaine de référence : Antifouling
Auteur Bagheripour E., Moghadassi A. R., Hosseini S. M., Van der Bruggen B., Parvizian F.
Année de parution : 2018.
Mots-clés : Composite graphene oxide/chitosan nanoplates, Nanofiltration, Rejection/antifouling characteristic, Surface property.
Type de document : Article de revue.
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A multi-step approach for testing non-toxic amphiphilic antifouling coatings against marine microfouling at different levels of biological complexity

Résumé : Marine biofouling on artificial surfaces such as ship hulls or fish farming nets causes enormous economic damage. The time for the developmental process of antifouling coatings can be shortened by reliable laboratory assays. For designing such test systems, it is important that toxic effects can be excluded, that multiple parameters can be addressed simultaneously and that mechanistic aspects can be included. In this study, a multi-step approach for testing antifouling coatings was established employing photoautotrophic biofilm formation of marine microorganisms in micro- and mesoscoms. Degree and pattern of biofilm formation was determined by quantification of chlorophyll fluorescence. For the microcosms, co-cultures of diatoms and a heterotrophic bacterium were exposed to fouling-release coatings. For the mesocosms, a novel device was developed that permits parallel quantification of a multitude of coatings under defined conditions with varying degrees of shear stress. Additionally, the antifouling coatings were tested for leaching of potential compounds and finally tested in sea trials. This multistep-approach revealed that the individual steps led to consistent results regarding antifouling activity of the coatings. Furthermore, the novel mesocosm system can be employed for advanced antifouling analysis including metagenomic approaches for determination of microbial diversity attaching to different coatings under changing shear forces.
Domaine de référence : Antifouling
Auteur Zecher Karsten, Aitha Vishwa Prasad, Heuer Kirsten, Ahlers Herbert, Roland Katrin, Fiedel Michael, Philipp Bodo
Année de parution : 2018.
Mots-clés : Antifouling, Bacteria diatom interaction, Biofilm, Biofouling, Fouling release, Mesocosm, Microfouling, Shear stress.
Type de document : Article de revue.
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Enhancement of graft density and chain length of hydrophilic polymer brush for effective marine antifouling

Résumé : 2-Hydroxyethyl methacrylate polymer brushes with various grafting densities and chain lengths were prepared through surface-initiated atom transfer radical polymerization. X-ray photoelectron spectra, ellipsometry measurement, contact angle measurement, and atom force microscope were used to characterize the prepared polymer brush. The biofouling assays of polymer brush were investigated by adhesion of Dunaliella tertiolecta, Navcular sp., and Bovine Serum Albumin protein and by static marine immersion field test. Besides, hydroxyl and sulfonate-terminated self-assembled monolayers, anionic charged 3-sulfopropyl methacrylate potassium salt polymer brush were prepared for comparison. Results suggest that the settlement of microorganisms can be largely reduced by polymer with enough polymer chain length and grafting density. More importantly, static immersion field tests indicate that hydrophilic polymer film with enough hydration layer thickness is necessary for long-term marine antifouling application. This comprehensive investigation is of great importance to understanding their influence on the adhesion of marine microorganism. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46232.
Domaine de référence : Antifouling
Auteur Yang Wufang, Zhang Ran, Wu Yang, Pei Xiaowei, Liu Yupeng, Zhou Feng
Année de parution : 2018.
Mots-clés : biomaterials, coatings, grafting, proteins, self-assembly.
Type de document : Article de revue.
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The antifouling effects of copper-oxide filler incorporated into paint-based protective films applied to steam surface condenser tubes

Résumé : Paint-based protective films (PPFs) are used to protect condenser tubes from corrosion and erosion but have been shown to be susceptible to biofouling. Here the biocidal properties of copper-oxide fillers incorporated into PPFs are explored in this paper. Specifically two PPFs filled with 20% and 50% filler (by weight) are tested in parallel with a non-biocidal ordinary epoxy PPF, and bare stainless steel tube. Using double-pipe co-current flow heat exchangers installed at a thermal power plant, actual cooling water exiting the condenser is evenly distributed between the test tubes. Heat transfer in the condenser is simulated by heated water flowing through each annulus of the double-pipe heat exchangers, thereby maintaining repeatable outer convection conditions. An exposure test of 125 days shows that the 50% biocide filled PPF has the lowest fouling factor of all the tubes. The non-biocidal epoxy has the highest fouling factor and the 20% filled PPF behaves similarly. Both of these are greater than the bare stainless steel control tube. The 50 % filled PPF is compared to the fouling of an existing admiralty brass tube and the shape of the fouling curves are similar. This evidence suggests that provided the filler concentration is sufficiently high, there is the potential for the copper-oxide filler to reduce the asymptotic composite fouling factor by virtue of its antibacterial properties.
Domaine de référence : Antifouling
Auteur Reuter Hanno C., Owen Michael, Goodenough John
Année de parution : 2018.
Type de document : Article de revue.
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Ecological responses to ocean acidification by developing marine fouling communities

Résumé : Increasing levels of CO₂ in the atmosphere are rapidly affecting ocean chemistry, leading to increased acidification (i.e., decreased pH) and reductions in calcium carbonate saturation state. This phenomenon, known as ocean acidification, poses a serious imminent threat to marine species, especially those that use calcium carbonate. In this dissertation, I use a variety of methods (field-based experiments, surveys, meta-analysis) to understand how marine communities respond to both natural and experimental CO₂ enrichment and how responses could be shaped by species interactions or food availability. I found that ocean acidification influenced community assembly, recruitment, and succession to create homogenized, low diversity communities. I found broadly that soft-bodied, weedy taxa (e.g., algae and ascidians) had an advantage in acidified conditions and outcompeted heavily calcified taxa (e.g., mussels, serpulids) that were more vulnerable to the effects of acidification, although calcified bryozoans and barnacles exhibited mixed responses. Next, I examined an important hypothesis of context dependency in ocean acidification research: that negative responses by calcifiers to high CO₂ could be reduced by higher energy input. I found little support for this hypothesis for species growth and abundance, and in fact found that, for some species, additional food supply exacerbated or brought out the negative effects of CO₂. Further, I found that acidification stress can tip the balance of community composition towards invasion, under resource conditions that enabled the native community to resist invasions. Overall, it is clear that acidification is a strong driving force in marine communities but understanding the underlying energetic and competitive context is essential to predicting climate change responses.
Domaine de référence : Antifouling
Auteur Brown Norah Elizabeth Maclean
Année de parution : 2018.
Type de document : Thèse.
Source : University of British Columbia
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Quantitative analysis of the complete larval settlement process confirms Crisp’s model of surface selectivity by barnacles

Résumé : For barnacle cypris larvae at the point of settlement, selection of an appropriate surface is critical. Since post-settlement relocation is usually impossible, barnacles have evolved finely tuned surface-sensing capabilities to identify suitable substrata, and a temporary adhesion system for extensive surface exploration. The pattern of exploratory behaviour appears complex and may last for several hours, imposing significant barriers to quantitative measurement. Here, we employ a novel tracking system that enables simultaneous analysis of the larval body movement of multiple individuals over their entire planktonic phase. For the first time, to our knowledge, we describe quantitatively the complete settlement process of cyprids as they explore and select surfaces for attachment. We confirm the ‘classic’ behaviours of wide searching, close searching and inspection that comprise a model originally proposed by Prof. Dennis Crisp FRS. Moreover, a short-term assay of cyprid body movement has identified inspection behaviour as the best indicator of propensity to settle, with more inspection-related movements occurring in conditions that also promote higher settlement. More than half a century after the model was first proposed by Crisp, there exists a precise method for quantifying cyprid settlement behaviour in wide-ranging investigations of barnacle ecology and applied studies of fouling management.
Domaine de référence : Antifouling
Auteur Aldred Nick, Alsaab Ahmad, Clare Anthony S.
Année de parution : 2018.
Type de document : Article de revue.
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Investigating the effect of biofouling on propeller characteristics using CFD

Résumé : Increasing pressure is being placed on the marine industry to address ship emissions, regulations to govern the efficient operation of ships in the form of the Energy Efficiency Design Index (EEDI) and Energy Efficiency Operation Index (EEOI) have recently come into force. All aspects of ship design and operation that impact the energy efficiency of ships are subject to revaluation. This paper investigates the detrimental effects of biofouling on the performance of Potsdam Propeller Test Case (PPTC) propeller using Computational Fluid Dynamics (CFD). A previously-developed CFD approach for approximating the surface roughness due to biofouling has been applied in order to predict the effects on propeller characteristics. The roughness effects of a typical coating and different fouling conditions on the propeller performance were predicted for various advance coefficients. The effect proved to be drastic with the most severe fouling condition resulting in a 11.94% efficiency loss at J=0.6 ranging to an alarming 30.33% loss at J=1.2 compared to the smooth condition. The study acts as a proof of concept for the proposed CFD assessment method which can be used as a very practical approach to predicting the impact of realistic fouling conditions on propeller characteristics and energy efficiency.
Domaine de référence : Antifouling
Auteur Owen David, Demirel Yigit Kemal, Oguz Elif, Tezdogan Tahsin, Incecik Atilla
Année de parution : 2018.
Type de document : Article de revue.
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Dextran- and Chitosan-Based Antifouling, Antimicrobial Adhesion, and Self-Polishing Multilayer Coatings from pH-Responsive Linkages-Enabled Layer-by-Layer Assembly

Résumé : To meet the demand for more environmentally friendly antifouling coatings and to improve fouling-resistant coatings with both “offense” and “defense” functionalities, polysaccharides (PSa)-based self-polishing multilayer coatings were developed for combating biofouling. Dextran aldehyde (Dex-CHO) and carboxymethyl chitosan (CMCS) were synthesized and alternatively incorporated via imine linkage into the multilayer coating in layer-by-layer (LbL) deposition. Surface plasmon resonance (SPR) technique was utilized to monitor the LbL assembly process. With increasing number of assembled bilayers, the antifouling performances against bovine serum albumin (BSA) adsorption, bacterial (S. aureus and E. coli) adhesion, and alga (Amphora coffeaeformis) attachment improved steadily. The self-polishing ability of the multilayer coatings was achieved via cleavage of pH-responsive imine linkage under acidic environments. As such, dense bacterial adhesion induced detachment of the outmost layer of the coatings. The efficacies of antifouling and antimicrobial adhesion were thus enhanced by the self-polishing ability of the multilayer coatings. Therefore, the LbL-deposited self-polishing dextran/chitosan multilayer coatings offer an environmentally friendly and sustainable alternative for combating biofouling in aquatic environments.
Domaine de référence : Antifouling
Auteur Xu Gang, Liu Peng, Pranantyo Dicky, Neoh Koon-Gee, Kang En-Tang
Année de parution : 2018.
Type de document : Article de revue.
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Ce projet est financé par le Fonds Européen de Développement Régional, la Région Normandie et le Conseil Départemental de la Manche.