Corrosion techniques and strategies for used fuel containers with copper corrosion barriers under deep geological disposal conditions:A review

Safe emplacement of high-level nuclear waste(HLNW)arising from the utilization of nuclear power is a frequently en-countered and considerably challenging issue.The widely accepted and feasible approach for the permanent disposal of HLNW involves housing it in a corrosion-resistant container and subsequently burying it deep in a geologic repository.The focus lies on ensuring the dur-ability and integrity of the container in this process.This review introduces various techniques and strategies employed in controlling the corrosion of used fuel containers(UFCs)using copper(Cu)as corrosion barrier in the context of deep geological disposal.Overall,these corrosion prevention techniques and methods have been effectively implemented and employed to successfully mitigate the corrosion challenges encountered during the permanent disposal of Cu containers(e.g.,corrosion mechanisms and corrosion parameters)in deep geologic repositories.The primary objective of this review is to provide an extensive examination of the alteration in the corrosion envir-onment encountered by the UFCs when subjected to deep geologic repository conditions and focusing on addressing the potential corro-sion scenarios.

Survey on biological fouling and corrosion of vessels

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Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar, India

Corrosion behaviour and biofouling characteristics of mild steel in three different coastal locations in the Gulf of Mannar,India have been studied over a period of 24 months.Oyster fouling was predominant at Open sea-Tuticorin,while barnacle fouling was dominant at both Mandapam and Harbour-Tuticorin.The rate of corrosion for 24 months exposure period was highest at Mandapam,where fouling was minimal.The surface of the mild steel was characterized by etchings&crevices beneath the hard foulers attached on it,at all the test locations.The depth of crevice caused by hard foulers was higher at Open sea-Tuticorin followed by Harbour-Tuticorin and Mandapam.The loss in ultimate tensile strength was more in Open sea-Tuticorin than the other two locations.Corrosion behaviour of mild steel is discussed based on the variation in the biofouling assemblage at the three test locations.

Effects of particle type on the particle fluidization and distribution in a liquid–solid circulating fluidized bed boiler

A liquid-solid circulating fluidized bed boiler is designed and built for visualization research by applying the fluidized bed heat transfer and fouling prevention technology to the water side of the boiler. Four types of engineering plastic particles with different physical properties are selected as the solid working media. The effect of particle types on the fluidization and distribution of particles in the boiler is investigated under different feedwater flow rates and amount of added particles by using the charge couple device image measurement and acquisition system. The results show that all kinds of particles can't be normally fluidized and accumulate in the drum at low amount of added particles and feedwater flow rate. The particles with great density and low sphericity are more likely to accumulate. The average solid holdup in the riser tubes increases with the increase in feedwater flow rate and the amount of added particles. The non-uniform degree of particle distribution in the riser tubes generally decreases with the increase in feedwater flow rate and the amount of added particles. The particles with small density and settling velocity have high average solid holdup in the riser tubes under close sphericity. In generally,the smaller the density and settling velocity, the more uniform the particle distribution in the riser tubes.Three-dimensional diagrams of the non-uniform degree of particle distribution in the riser tubes of the boiler are established.

Corrosion inhibition of stainless steel by a sulfate-reducing bacteria biofilm in seawater

Corrosion inhibition of stainless steel due to a sulfate-reducing bacteria （SRB） biofilm in seawater was studied. By atomic force microscopy, a layer of fish-scale-like biofilm was found to form as stainless steel coupons were exposed to the culture media with SRB, and this biofilm grew more and more compact. As a result, coupons＇ surface under the biofilm turned irregular less slowly than that exposed to the sterilized culture media. Then, physicoelectric characteristics of the electrode/biofilrn/solution interface were investigated by electro- chemical impedance spectroscopy （EIS）, and the coverage of the biofilm as well as the relative irregularity of coupons＇ surface was also re- corded by EIS spectra.. Finally, anodic cyclic polarization results further demonstrated the protective property of the biofilm. Therefore, in es- timation of SRB-implicated corrosion of stainless steel, not only the detrimental SRB metabolites but also the protective SRB biofilm as well should be taken into account.

Temperature control and cracking prevention in coastal thin-wall concrete structures

A three-dimensional finite element program for thermal analysis of hydration heat in concrete structures with a plastic pipe cooling system is introduced in this paper. The program was applied to simulation of the temperature and stress field of the Cao＇e Sluice during the construction period. From the calculated results, we can find that the temperaiure and stress of concrete cooled with plastic pipes are much lower than those of concrete without pipes. Moreover, plastic pipes could not be corroded by seawater. That is to say, a good effect of temperature control and cracking prevention can be achieved, which provides a useful reference for other similar nearshore concrete projects.

Hard Foulers Induced Crevice Corrosion of HSLA Steel in the Coastal Waters of the Gulf of Mannar (Bay of Bengal), India

In the present study an attempt has been made to investigate the relationship between the variations in the fouling assemblage and corrosion behaviour of HSLA steel at three coastal locations in the Gulf of Mannar, India, over a period of 24 months. Oyster fouling was dominant in the Tuticorin open sea, while barnacles were the major foulants in the Tuticorin harbour and Mandapam. The fouling load in the Tuticorin waters was higher when compared to the Mandapam waters. The corrosion rates decreased progressively with the immersion time at all three test locations. In the Tuticorin open sea, the corrosion rates were higher when compared to the other two locations throughout the study period. The surface of the coupons was characterized by crevices beneath the hard foulers in the Tuticorin harbour and Mandapam, whereas in the Tuticorin open sea, the coupons experienced crevices of a tunneling nature. The percentage of the loss of the tensile strength increased with time at all the test locations.

Corrosion and Its Inhibition in Water-Based Drilling Fluid Used in Onshore Oilfied

This study deals with onshore oilfield drilling fluid system to drill corrosion. Corrosion under static and dynamic conditions of the drilling fluid was evaluated. The effect of temperature and pressure on corrosion was examined. Corrosion was more severely affected by temperature compared to pressure. The combined effect of a deoxidizing agent and an inhibitor was observed to exhibit better protection against corrosion by the drilling fluid.

适用于掺氢燃气轮机的新型环境/热障涂层

【目的】随着国家“双碳”战略(碳达峰、碳中和)的实施,现有的热防护涂层结构难以满足未来燃气轮机热防护涂层的要求。针对掺氢燃气轮机对热防护涂层的需求,提出了抗高温腐蚀的新型环境/热障涂层(environmental/thermal barrier coatings,E/TBC)结构的概念。【方法】从热防护涂层材料和涂层结构的角度,简要回顾及分析了热障涂层(thermal barrier coatings, TBC)、环境障涂层(environmental barrier coatings, EBC)、热障/环境障涂层(thermal/environmental barrier coatings,T/EBC)和热环境障涂层(thermal environmental barrier coatings,TEBC)的发展历程和研究现状,进而考察上述涂层结构与掺氢燃气轮机对热防护涂层需求之间的差距。【结果】将EBC的功能叠加到目前掺氢燃气轮机的热防护涂层上,从而在高温合金基体上形成一种抗高温腐蚀的新型E/TBC结构具有合理性。【结论】通过初步试验,证明E/TBC结构适用于掺氢燃气轮机抗高温水氧腐蚀的热防护涂层要求,指出应大力开展这种新型E/TBC热防护涂层的理论和应用研究。

水井管道腐蚀因素分析及镍磷镀层防护性能评价

胜利油田作业跟踪27口新管漏失井,均为单根外壁腐蚀,油管腐蚀问题给油田生产带来了极大的安全隐患。目前,油田注水管道系统采取的防腐措施主要有采用耐腐蚀管材、涂层防腐、镀层保护、氮化技术、化学防腐及阴极保护等几大类。文章研究了某井下采出液条件下水井管道在不同运行工况(不停井)中出现锈蚀现象的产生原因及机理,对该井漏失管开展了镍磷镀层防护实验并进行效果评价,确定该条件下管线发生锈蚀主要受井筒设计状况和套管内压力影响。根据实际情况开展镀层保护实验,并通过镀层保护方法提出后续防护措施。

套损井腐蚀机理分析及防治技术研究

油田套损井是由于套管腐蚀、机械损伤等原因导致的套管失效现象。通过深入分析油田套损井的腐蚀机理及其对油田生产的影响,探讨了相应的防治技术。研究发现,套管腐蚀主要包括均匀腐蚀、局部腐蚀和应力腐蚀,其形成机制复杂,受环境因素、材料因素和操作因素的多重影响。通过电化学检测和无损检测技术,可以有效评估腐蚀程度,制定针对性的防腐措施。同时,还介绍了材料选择、阴极保护技术和缓蚀剂应用等防治技术,并通过实际案例验证了其有效性。研究表明,科学合理的腐蚀防治技术能显著延长套管的使用寿命,确保油田的安全稳定生产。

某350 MW机组对冲锅炉燃用高碱煤炉膛腐蚀防治研究

为降低燃料采购成本,保证燃料供应,甘肃某电厂大比例掺烧了部分新疆高碱的广汇煤和新疆能源煤。高碱煤掺烧后,锅炉出现较严重的受热面高温腐蚀和结焦现象,负荷最高只能带到85%ECR。为减轻高温腐蚀,对锅炉开展了煤质特性、燃烧优化调整和设备改进技术研究。结果表明:锅炉燃用较低硫份煤的情况下仍然发生较严重的高温腐蚀,主要与新疆煤中的钠、钙等碱金属及氯质量分数较高有关,通过提高氧量、降低一次风量、减弱燃烧器外二次风旋流强度和开大贴壁风等运行调整手段,可以一定程度上改善水冷壁高温腐蚀特性;彻底解决该问题,还需使用添加剂、进行防高温腐蚀喷涂、增加吹灰器、改进贴壁风和燃烧器设计等技术途径。该研究成果可为解决高碱煤掺烧过程中出现类似问题的电厂提供借鉴和参考。

CaO_(2)/Fe^(2+)协同控制污水管道硫化物的效能

针对污水管道硫化物的生成和积累导致管道腐蚀、臭味逸散问题,提出CaO_(2)/Fe^(2+)协同控制方法.研究了不同CaO_(2)和Fe^(2+)投加量条件下硫化物氧化动力学和作用机制,分析了pH值、温度、无机离子对硫化物氧化去除效能的影响,通过连续流反应评估了CaO_(2)/Fe^(2+)协同控制方法对污水管道硫化物控制效能.结果表明CaO_(2)/Fe^(2+)协同氧化去除硫化物符合伪一级反应动力学,反应过程中生成的HO·是氧化硫化物的主要活性物种,当CaO_(2)和Fe^(2+)物质的量比为4:1时,氧化速率最优;硫化物氧化速率与pH值呈现负相关,与温度呈现正相关,水中常见阴离子和铵离子对氧化速率无显著影响;CaO_(2)/Fe^(2+)协同投加可有效控制硫化物生成,当药剂投加量与污水比例(W/V)为0.30%时,硫化物50%生成率恢复周期达8.34d.

无锡自抛光防污涂料研究进展

海洋污损生物附着问题一直影响海洋运输与海洋工程行业的发展。为减轻海洋生物附着所带来的困扰,防污涂料被广泛应用,而无锡自抛光涂料(TFSPC)因其卓越的防污性能和低毒性而成为防污涂料市场的主流产品。详细探讨了无锡自抛光涂料的工作机理、成分组成以及目前的应用状况。

硫酸盐还原菌腐蚀防治技术研究

自然环境中硫酸盐还原菌的广泛发育易引起诸多腐蚀性问题,严重影响生态环境质量并危及相关工业安全生产,因此备受广大学者关注。通过梳理文献,对硫酸盐还原菌腐蚀防治技术进行综述。首先基于微生物的代谢过程,简单介绍了硫酸盐还原菌介导的腐蚀行为;其次针对其介导腐蚀,简要概述了物理、化学和生物等防治方法,总结了各方法的应用特性及发展前景;随后主要从微生物活性抑制和产物消耗这2个角度,重点分析归纳了基于硝酸盐还原作用的硫酸盐还原菌腐蚀防治机理,并综述了相关的实践应用研究情况。最后,针对硫酸盐还原菌腐蚀防治技术提出几点思考,并对其进一步发展做出展望。

金属超疏水涂层制备及其耐腐蚀性能研究进展

金属腐蚀不仅对经济和环境带来严重影响,甚至可能威胁人类生命安全。近年来,超疏水表面因其特殊结构在防腐蚀应用中具有巨大前景,调控超疏水表面也作为一种新型耐腐蚀方法引起研究者的关注。本文介绍了超疏水模型及其表面防腐蚀的基本理论,重点综述了不同方法在不同金属基底所制备出的超疏水表面在防腐蚀方面的应用,不过目前所制备的超疏水表面仍面临着实际应用的挑战,为此本文归纳总结了具有持久耐腐蚀性超疏水表面的发展趋势。

浅谈乘用车防腐设计和预防

主要介绍了汽车腐蚀的因素,明确了汽车防腐的基础设计,针对具体车型设计中开展干湿区分区、电泳膜厚设计以及在制造工艺环节中对基础防腐设计的影响因素和预防对策做了进一步阐述,通过案例展示了提前设计和试验对防腐设计的重要性。

纳米高熵陶瓷涂层在超超临界1000 MW机组锅炉的防结焦耐腐蚀应用研究

针对某台超超临界1000MW机组燃用准东煤锅炉水冷壁出现的沾污结渣、高温腐蚀问题,基于锅炉的燃烧煤种特性、结焦状况以及腐蚀类型,开展了纳米高熵陶瓷涂层在锅炉后墙水冷壁燃尽风区域的工程验证试验。采用宏观检查、扫描电子显微镜(scanning electron microscope,SEM)、X射线衍射(X-ray diffraction,XRD)、拉曼光谱、摩擦系数及表面能测试等方法,分析了纳米高熵陶瓷涂层的使用效果,揭示了纳米高熵陶瓷涂层的防沾污结渣、耐腐蚀机制。试验结果表明,涂层在锅炉运行11个月后完好,表面无明显结焦物、无明显腐蚀凹坑,管壁未发生明显减薄。纳米高熵陶瓷涂层能够较好地解决锅炉水冷壁沾污结渣以及高温腐蚀的问题,为燃用准东煤锅炉的安全运行提供保障。

含氮、硫杂环酯类衍生物的合成及其摩擦学性能研究

合成了4种含氮、硫杂环酯类衍生物(A1~A4)。采用核磁共振氢谱(^(1)HNMR)和飞行时间质谱(MALDI-TOF-MS)对所得的化合物结构进行了表征;研究了4种化合物的油溶性、热稳定性和抗腐蚀性;在四球摩擦磨损试验机上系统考察了化合物在菜籽油中的摩擦学性能;利用扫描电子显微镜(SEM)和能谱分析仪(EDS)观察和分析了钢球磨斑的表面形貌和元素组成。结果表明,4种化合物均具有良好的油溶性、热稳定性和抗腐蚀性,当化合物A4的质量分数达到1.0%时,钢球的磨斑直径(WSD)比在菜籽油中降低了50.7%。SEM显示4种化合物的加入能明显减小WSD,减少表面磨损,EDS结果表明化合物在摩擦过程中形成了复杂的反应膜。

Polydopamine wrapped polyaniline nanosheets:Synthesis and anticorrosion application for waterborne epoxy coatings

Two-dimensional materials have been proved to be effective in improving the performance of anticorrosive coatings.However,most of the reported two-dimensional materials only have the ability to passively block corrosive media and cannot effectively inhibit localized corrosion reactions at the metal/coating interface.Herein,we first synthesized a novel polyaniline(PANI)nanosheet with both barrier and passivation functions for metals.In addition,polydopamine(PDA)wrapped PANI nanosheets(PANI@PDA)were obtained by in situ self-polymerization reaction of dopamine on the PANI surface,which enhance its interfacial interaction with polymeric resin.The chemical structure,morphology and corrosion inhibition properties of the nanosheets were systematically analyzed.The incorporated PANI@PDA nanosheets in composite coating provide a longer penetration path for corrosive mediums.Secondly,the uniformly dispersed two-dimensional nanosheets induce the formation of passivation film on the metal substrate.The protective effect of PANI@PDA nanosheets on coatings was verified by electrochemical impedance spectroscopy(EIS).Results indicated that the prepared composite coating exhibited excellent corrosion resistance throughout the test cycle.This simple and effective modification strategy based on conductive polymers provides a new insight into the development of environmentally adaptive composite coatings with active and passive protection.