保温层下腐蚀分析及防护探讨

在石油石化行业,管道及设备保温层下的腐蚀是不容忽视的问题.本文从保温层下腐蚀机理成因分析,提出了减缓腐蚀的对策.分别从防腐涂层选取、保温层材料设计及腐蚀监测技术等方面简单讨论了防护措施.     

水煤浆气化装置的腐蚀与防护

某公司的水煤浆气化装置在运行过程中暴露出很多的腐蚀、结垢和堵塞问题.对现场装置进行腐蚀调研,通过工艺流程、腐蚀性介质以及腐蚀流程分析,判断腐蚀类型和腐蚀规律.从选材推荐和腐蚀监测检测方面提出了防护对策,抑制了设备和管道腐蚀,保障了装置的长周期安全稳定运行.     

埋地油气管道腐蚀机理研究及防护

埋地油气管道的腐蚀一直是油气储运及集输工程的一个重要问题.分析了埋地油气输送管道腐蚀的各种形式及主要腐蚀机理.针对输油管道的腐蚀问题,从土壤微生物、理化性质以及交流电对管道的腐蚀影响等方面进行了分析.介绍了埋地油气混输管道腐蚀防护的方法:加缓蚀剂、外涂层、内涂层和衬里保护、阴极保护法、杂散电流排流保护等.提出要提高油气...     

不同水质工况下电厂铜管的腐蚀

电厂铜材的腐蚀问题日益突出,引起铜腐蚀的原因是多方面的,其中水质工况是非常重要的因素之一.从水中主要阴离子、阻垢剂、缓蚀剂、微生物生长等方面探讨了不同水质工况下铜管的腐蚀作用.     

CDU蒸馏塔塔顶系统中氯化物防腐蚀研究

为应对CDU蒸馏塔塔顶系统中氯化物腐蚀问题,将氯化物分为可萃取氯化物和不可萃取氯化物,提出了相应的测量方法.从酸性冷凝腐蚀和氯化铵腐蚀两方面分析蒸馏塔塔顶系统氯化物的腐蚀影响,明确适宜采用的检验检测和在线监测手段,并提出针对不同腐蚀机理选用有效的腐蚀控制与防护措施,现场应用效果良好.     

海底油气集输管道的腐蚀问题分析及防治措施研究

海洋石油开采中海底管道运行最大的风险是管道易遭受腐蚀的威胁,因此针对油气集输管道的腐蚀问题进行原因分析,研究减缓或避免管道内外腐蚀的措施至关重要.本文从油气集输管道的表面处理、电化学防护、应用化学缓蚀剂等方面提出了进行油气集输管道腐蚀防治的解决方案.     

The Causes for Corrosion in MDEA CO2 Removal Unit

针对MDEA脱碳系统运行一段时间后出现的严重腐蚀问题,从工艺角度,探讨腐蚀原因,并采取措施改进.     

H12块油系统腐蚀现状及防腐治理规划

胡庆油田胡十二块是胡庆油田三大主力区块之一.油系统表现出的腐蚀问题逐年呈现严重趋势.为进一步总结经验,查找不足,结合胡十二块实际生产情况,本文从油系统腐蚀现状分析入手,主要介绍了在胡十二块腐蚀治理的主要技术和取的效果,提出了下步措施方向     

混凝土酸雨侵蚀研究进展

与硫酸、硫酸盐等侵蚀相比,酸雨对混凝土的腐蚀有更复杂的腐蚀机理和影响因素.本文首先从酸雨对混凝土强度、弹性模量、酸性化、钢筋锈蚀等影响方面介绍了酸雨侵蚀危害性.然后综合评述了近年来国内外有关混凝土酸雨腐蚀机理、主要影响因素和评价方法等最新理论研究成果和试验.并对需进一步研究的问题提出了建议.     

太阳能热发电高温熔盐腐蚀机理及其影响因素

为了解决太阳能热发电中存在的腐蚀行为,从腐蚀机理和影响因素两方面分析了硝酸盐熔盐流体中存在的金属腐蚀行为.理论计算显示,当O2-浓度小于23或者材料电极电压低于-1.6 V时,在碳钢材料表面才能生成稳定的耐腐蚀性氧化层.为了进一步分析金属材料在硝酸盐熔盐流体中的腐蚀问题,从硝酸熔盐的工作温度、杂质、成分变化、金属材料的...     

Effect of the Incorporation of PVC on the Mechanical Properties of the Jute-Reinforced LLDPE Composite

Jute fabrics-reinforced linear low density polyethylene (LLDPE) matrix composites (50 wt% fiber) were prepared by compression molding and mechanical properties were studied. Polyvinyl chloride (PVC) matrix was incorporated instead of LLDPE in the jute based composites and their mechanical properties were investigated and compared with the control composites. It was found that with the increase of PVC in the LLDPE based composites, the mechanical properties were found to improve significantly. Degradation tests of the composites for upto 24 weeks were performed in soil medium. Water uptake and Thermo-mechanical properties of the composites were also studied.     

Application of the general rate model with the Maxwell-Stefan equations for the prediction of the band profiles of the 1-indanol enantiomers

The adsorption isotherm data of R- and S-1-indanol and of their racemic mixture on cellulose tribenzoate were measured by frontal analysis. These experimental data were fitted to the single-component and the modified competitive Bilangmuir isotherms. The overloaded elution profiles of bands of the pure enantiomers and of the racemic mixture were calculated for different sample sizes, using the best competitive isotherm model and the General Rate Model of chromatography coupled with the generalized Maxwell-Stefan equation that describes the surface diffusion flux. The calculated and the experimental profiles were found to be in excellent agreement in all cases. The parameters of the model of the mass transfer kinetics were derived from the band profiles obtained for the pure enantiomers. The same values of these parameters give an excellent prediction of the profiles of multicomponent bands. The new model described here allows a satisfactory interpretation of the competitive mass transfer kinetics.     

钛合金胶接接头耐水性的研究

本文介绍了几种表面处理方法对钛合金胶接性能的影响，并讨论了钛合金胶接接头的耐水性能。     

Dependence of the dyeability of modified cotton on the substituents and the nature of the dye

Cotton cellulose was chemically modified by introducing acrylamide, acrylonitrile and carboxyalkyl moieties in the form of groups or polymers. In carbamylethylated, cyanoethylated and carboxymethylated cotton, these moieties are in monomeric groups, whereas, in graft copolymers of cotton cellulose with acrylamide, acrylonitrile or acrylic acid, the moieties are in polymeric forms. These substrates were dyed independently using direct, acid, basic or reactive dyes. Results showed that at roughly equal nitrogen content, polyacrylamide–cotton graft copolymer exhibited a much higher colour strength than carbamylethylated cotton when the two substrates were dyed using basic dye. The opposite is the case for direct and reactive dyes. The acid dye produced comparable colour strengths. Similar trends were observed when the other samples were dyed with these four dyes. The results were explained in terms of microstructural changes in the physical and chemical structure of cotton caused by the etherification and grafting reactions.     

Effects of the Physicochemical Properties of Metronidazole-Corn Starch Mixtures on the Parameters of the Pellets in the Wet-Granulation Method

Whether the surface free energy of a powder mixture (metronidazole-corn starch) depends on the proportions of the components and how the forces of cohesion and adhesion between the particles affect their interactions as functions of the proportions of the components were investigated. Pellets were produced from the powder mixtures. The interactions between the powder mixtures and the binding agent were first investigated on the basis of the spreading coefficients (S) calculated from the surface free energy. The mechanical properties of the pellets produced were predicted from the S values. Pellet parameters were evaluated as functions of the corn starch content. The overall aim was to investigate the role of the surface free energy of two-component powder compositions in pellet production. In contrast with predictions from the S values, pellets with a more porous and loose texture and with unfavourable mechanical properties can be produced as the S values are increased.     

不同芯材热敏变色微胶囊的制备及性能研究

以隐色染料结晶紫内酯、酚酞、苯酚红、甲基红为电子给予体、显色剂双酚A为电子接受体和十二醇为溶剂,制备了可逆热致变色复配物,以密胺脂为壁材,通过原位聚合法进行微胶囊化研究,并对制备条件进行了优化。利用扫描电子显微镜、热重分析法等对微胶囊进行了结构与性能表征。     

带滤机在种分玛瑙填料生产中的应用

首先介绍了国内外复合材料行业使用的填料氢氧化铝的发展趋势;其次介绍了带式真空过滤机在国内外发展及应用的概况,并对其工作原理做了陈述。最后叙述了其在种分玛瑙生产线上的应用情况、存在问题及解决方法。     

碳化塔内壁鼓包的测定与修复

报道了对某化肥厂碳化塔内壁鼓包进行检测的过程和结果以及修复方法。首先对塔内外壁进行了检验。随后对塔体每个筒节和每个鼓包用测厚仪进行壁厚测定,并对选定的鼓包进行切片检验。最后对鼓包进行了修复。修复后的碳化塔运行状况良好。由此总结出碳化塔修复的要求和技术措施,并对该设备的安全运行提出了建议。     

纳米无机粒子的分散及改性塑料研究进展

阐述了纳米无机粒子团聚的分类和原因,介绍了几种克服其团聚的方法;综述了纳米塑料常见的制备方法以及纳米塑料的优异性能与结构性能的表征方法。     

噁二唑啉类化合物合成方法综述

噁二唑啉类化合物由于其良好的生物活性广泛应用于医药,农药领域。将噁二唑啉杂环引入其他化合物中,往往能生成一系列具有广谱生物活性的新化物。因此,在新药设计中,噁二唑啉杂环常被用于化合物的结构修饰。近年来,有关这类化合物的合成方法不断得到更新。作者对近年来噁二唑啉类化合物合成方法及反应机理进行了全面综述。