用于含聚合物钻井液的缓蚀剂研究

    通过线性极化法筛选出单组分缓蚀效果较好的钼酸钠、含硅化合物为复配的基本配方.利用极化曲线法评定复合缓蚀剂的缓蚀效果,并研究其缓蚀机理.结果表明,复配后的缓蚀效果优于未添加缓蚀剂或添加单组分缓蚀剂,说明复合缓蚀剂各组分之间具有一定的协同缓蚀效果,能够有效地在金属表面形成具有互补性的保护膜,能有效提高自腐蚀电位,降低腐蚀电流.用交流阻抗法分析了缓蚀剂的缓蚀机理,并用重量法进行了验证.     

文昌13-1/2油田缓蚀剂优化评价与现场应用

文昌油田WC13-1/2目前处于中高含水开采期,现用缓蚀剂已无法适应油田产液量、油田综合含水、海底输油管线压力、温度、流速的变化;因此,对在用缓蚀剂进行针对性的优化势在必行。本文针对文昌油田油水性质及现场工况条件,开展静态、动态腐蚀评价实验,优化筛选出了适用于现场的缓蚀剂,现场实验证明了其具有优良的缓蚀性能;同时,建立了一套系统的层进式的缓蚀剂筛选方法,为海底输油管线的腐蚀防护提供了有力的技术支持。     

某油田海底输油管线X65钢缓蚀剂筛选与评价方法

本文首先利用高温高压电化学反应釜对8种不同的缓蚀剂对X65钢在某油田海底输油管线工况下的作用效果进行了筛选和评价,然后利用高温高压动态反应釜对这8种缓蚀剂进行了相同工况下的传统腐蚀模拟实验,利用失重法计算了其腐蚀速率及缓蚀剂的缓蚀效率。对比高温高压电化学法及高温高压动态腐蚀模拟实验的筛选与评价结果,发现高温高压电化学法所测得的腐蚀速率明显偏高,但所测缓蚀效率及区分不同缓蚀剂之间效果的优劣与高温高压动态腐蚀模拟实验所测基本一致,可用于缓蚀效率的快速测定及缓蚀剂的初步筛选评价。     

应用线性极化电阻法现场筛选缓蚀剂

采用美国ROHRBACK COSASCO公司生产的线性极化电阻（LPR）腐蚀速率测定仪在渤海某油气田进行缓蚀剂现场筛选。筛选出缓蚀剂BHH-06缓蚀效果最佳;另外,现场正在注入的缓蚀剂BHH-05注入浓度太低（大约2×10-6）,使得其缓蚀效率不能达到最佳效果,建议在使用BHH-06替代BHH-05之前,将其注入浓度增加至15×10-6～18×10-6。     

G105钻具用钢在8%KCl溶液中缓蚀剂的研究

采用旋转挂片法对G105在8%的KCL溶液中的缓蚀剂进行筛选;通过缓蚀剂加入前后极化曲线的变化,分析了缓蚀剂的缓蚀机理;根据滞后环实验,研究了缓蚀剂在8%KCL溶液中对G105的点蚀抑制作用。结果表明:(1)2%含硅复合缓蚀剂(水玻璃)+10mg/L HEDP+15mg/L氯化锌缓蚀效果最好,其缓蚀率高达98.5%;(2)缓蚀剂的加入对腐蚀反应的阴极过程有明显的抑制作用,同时对腐蚀反应的阳极过程也有一定的抑制作用,该缓蚀剂是以抑制阴极过程为主的混合型缓蚀剂;(3)对点蚀有很好的抑制效果。     

咪唑啉类缓蚀剂研究和应用的进展

    综述了由于自然条件(如潮湿空气、酸雨等)、工业酸洗、油气井酸化等原因,不同腐蚀介质的腐蚀机理,咪唑啉类化合物作为一类新型、低毒、高效的水基缓蚀剂,它的应用很好的抑制和减缓了金属腐蚀;概述了咪唑啉类缓蚀剂在不同腐蚀环境下的缓蚀效果以及咪唑啉类缓蚀剂在模拟腐蚀介质体系的应用新进展.     

M24油井采出液系统的腐蚀行为与缓蚀剂的研究

本文通过EDS法分析静态挂片表面的元素组成,将动电位扫描极化曲线和滞后环等电化学实验相结合,对实验室和现场垢样的SEM和XRD的形貌和组成进行分析,研究了Q235钢在M24油井采出液系统中的腐蚀行为,用旋转挂片法对缓蚀剂进行了筛选,参照GB/T6324.1做了水溶性测定实验,参照SYT5273-2000实验方法进行了乳化倾向测定。结果表明M24油井采出液系统中引起腐蚀穿孔的原因是垢下腐蚀而不是点蚀,腐蚀的速度受腐蚀反应的阳极过程控制;用旋转挂片仪筛选出的自制缓蚀剂用量50mg/L,缓蚀率超过90%,缓蚀剂起到缓蚀作用的根本原因是抑制了电极反应的阳极过程;缓蚀剂在水中溶解性好;有轻微乳化现象,但在水相中的有效成分没有减少。     

20钢在含甲醇污水中的缓蚀剂选择及其缓蚀性能

为了减缓甲醇回收系统的腐蚀,通过失重法对20钢在含甲醇模拟污水中的缓蚀剂进行了筛选及优化,并通过极化曲线法研究了缓蚀剂的缓蚀性能;通过能谱(EDS)分析和阻垢性能试验研究了缓蚀剂的阻垢性能。结果表明:聚磷酸钠、有机膦A和ZnCl_2以质量比2∶1∶2复配,且该复合缓蚀剂用量为90mg/L时,缓蚀性能最好,缓蚀率达到95.47%;该复合缓蚀剂是抑制电极阳极反应为主的混合型缓蚀剂;含磷缓蚀剂在20钢表面形成膜从而有效地阻挡了腐蚀介质对基体的腐蚀,且该复合缓蚀剂具有较好的阻垢作用,阻垢率达83.33%.     

水溶性缓蚀剂TP/K-3的研制与机理探讨

介绍了塔河油田生产系统产出液的腐蚀特性.根据现场用缓蚀剂油溶性好而缓蚀效果较差的状况,以油酸、二乙烯三胺和二甲苯为原料,通过合成、复配与评价试验,室内合成了五种水溶而油微缓蚀剂,确定了适用于该油田油井产出液的水溶而油微溶油井缓蚀剂系列TP/K-3,并通过红外光谱进行表征.应用静态挂片,电化学极化曲线评价其缓蚀性能及缓蚀机理.实验结果表明,TP/K-3系列缓蚀剂除具有很强的适应性外,还对20#钢具有抗CO2和H2S等酸性介质的优点.当缓蚀剂的加入量在100mg/L时,其缓蚀效果可达90%左右,平均静态腐蚀速率小于0.076mm/a.     

缓蚀剂对天然气脱水系统的防腐蚀阻垢作用

针对天然气浅冷装置乙二醇脱水系统存在的腐蚀结垢现象,对四种缓蚀剂单独和复配使用时用量、腐蚀时间、溶液pH值、配比等因素对缓蚀效果的影响进行了研究,获得了最佳的复配缓蚀剂,该缓蚀剂在试验条件下的缓蚀效率可达93.82%。通过天然气浅冷站脱水系统的现场应用,该最佳复配缓蚀剂的平均缓蚀效率达到74%。     

碳钢在废弃钻井液中的腐蚀行为研究

采用失重法,动电位扫描、扫描电镜及俄歇电子能谱等手段,研究了碳钢在废弃钻井液化学脱稳处理过程中的腐蚀行为。结果表明：化学脱稳后的废弃钻井液腐蚀性增加,氧含量、ＰＨ值、温度、固相含量、金属阳离子及混凝剂等都对体育馆２行为有很大的影响;除氧和添加吸附型缓蚀剂可减缓废弃钻井液的腐蚀。     

4-Substituted anilinomethylpropionate: New and efficient corrosion inhibitors for mild steel in hydrochloric acid solution

4-substituted anilinomethylpropionate namely 3-anilinomethylpropionate (Inh-1), 3-(4-methylanilino)methylpropionate (Inh-2) and 3-(4-chloroanilino) methylpropionate (Inh-3) were synthesized and investigated as corrosion inhibitors of mild steel in 1 N HCl solution using weight loss, polarization resistance, Tafel polarization and electrochemical Impedance spectroscopy techniques. The inhibition efficiency of the synthesized inhibitors followed the order Inh3 > Inh2 > Inh1. The inhibiting action of the all inhibitors was found to depend on electronic nature of functional groups present in inhibitors. Potentiodynamic polarizations suggest that all inhibitors are mixed type in nature. Electrochemical impedance spectroscopy was also used to investigate the mechanism of corrosion inhibition.     

M13井采出水腐蚀与缓蚀机理的研究

用SEM、EDS法分析手段、动电位扫描极化曲线和滞后环实验等电化学方法研究了A3钢在M13井采出液水相中的腐蚀机理.结果表明,M13井采出液引起局部腐蚀的原因是形成CaCO<,3>垢的垢下腐蚀而不是点蚀,腐蚀的速度受腐蚀反应的阳极过程控制.用旋转挂片仪筛选出的WJF-6缓蚀剂用量为50 mg/L、在M13井采出液中使用时,实验室中测出的缓蚀率超过90%,其根本原因是抑制了电极反应的阳极过程.     

Inhibition effect of 4-phenylthiazole derivatives on corrosion of 304L stainless steel in HCl solution

Some 4-phenylthiazole derivatives were tested as corrosion inhibitors for 304L stainless steel in 3.0 M HCl using weight loss and galvanostatic techniques. The results showed that the inhibition efficiency increases with increasing the concentration of the 4-phenylthiazole derivatives. Polarization measurements showed that these derivatives act as mixed-type inhibitors. The adsorption of these inhibitors on the surface of stainless steel follows Temkin’s adsorption isotherm and kinetic model. The effect of temperature on the corrosion was investigated by the weight loss method and some thermodynamic parameters were calculated. The synergistic influence caused by thiocyanate ion on the inhibition of corrosion of 304L stainless steel in 3.0 M HCl in the presence of 4-phenylthiazole derivatives has been studied using weight loss method. The inhibition action of these 4-phenylthiazole derivatives was discussed in terms of its adsorption on the metal surface.     

Interaction of inhibitors with corrosion scale formed on N80 steel in CO2‐saturated NaCl solution

The performance of the selected inhibitors, including thioglycolic acid (TGA), diethylenetriamine (DETA), and naphthene acid imidazolines (IM), on the bare surface of N80 steel and its scaled surface pre‐corroded in CO₂‐saturated 1%NaCl solution was investigated by weight‐loss method, electrochemical measurements using rotating cylinder electrode and surface analytical methods (SEM, XRD, and EPMA). The results indicate that there is a remarkable difference in inhibition efficiency of inhibitors on the N80 steel with and without pre‐corrosion scale. The synergistic effect between inhibitors and corrosion scale not only depends on the size of inhibitor molecules, but also depends on the interaction of the inhibitor with the corrosion scale. It shows that IM and DETA have a good positive synergistic effect with the corrosion scale formed on N80 steel, although DETA has no inhibition efficiency for bare N80 steel, which can easily enter into the apertures of the corrosion scale, and block the active sites on the metal surface and the diffusion routeways of the reactant so as to depress the corrosion of the substrate metal. While TGA shows excellent inhibition efficiency on bare N80 steel, but it has an antagonistic effect with the corrosion scale although it has a small molecular weight as well as DETA, because TGA can dissolve corrosion scale and break its integrality and protectiveness performance.     

Corrosion monitoring of mild steel in sulphuric acid solutions in presence of some thiazole derivatives – Molecular dynamics, chemical and electrochemical studies

The physical behavior of three selected thiazole derivatives, namely 2-Amino-4-(p-tolyl)thiazole (APT), 2-Methoxy-1,3-thiazole (MTT) and Thiazole-4-carboxaldehyde (TCA) at iron (1 1 0) surface dissolved in aqueous solution were studied via molecular dynamics (MD) simulations. From the calculated binding energies, APT showed preferred adsorption on the steel surface among the three tested thiazole derivatives. The inhibition performance of the three thiazoles on the corrosion of mild steel in 0.5 M H₂SO₄ solutions was investigated at 25 °C. Measurements were conducted under various experimental conditions using weight loss, Tafel polarization and electrochemical impedance spectroscopy. Electrochemical frequency modulation (EFM) technique was also employed here to make accurate determination of the corrosion rates and test validation of the Tafel extrapolation method for measuring corrosion rates. Polarization curves showed that the three thiazole derivatives were of mixed-type inhibitors for mild steel corrosion in 0.5 M H₂SO₄ solution. EFM results were in agreement with other traditional chemical and electrochemical techniques used in corrosion rate measurements. Chemical and electrochemical measurements are consistent with computational study that APT is the most effective inhibitor among the tested thiazoles.     

中性介质中Q420qD高强桥梁钢的腐蚀行为

通过中性盐雾腐蚀试验、电化学测试等手段研究了Q420qD超低碳贝氏体高强桥梁钢和其对比材料F500L-Z普钢在中性介质中的腐蚀行为.结果表明:Q420qD超低碳贝氏体高强桥梁钢的耐腐蚀性优于F500L-Z普钢;其电化学阻抗值随金属材料浸泡时间的延长而增大,说明随着浸泡时间的延长,金属材料表面锈层不断加厚,逐渐增加了阻挡电解液对金属材料的侵蚀及金属材料表面金属原子失去电子向溶液中迁移的过程.     

Experimental and theoretical evaluation of semicarbazones and thiosemicarbazones as organic corrosion inhibitors

The inhibition ability of four thiosemicarbazones (1A–D) and two semicarbazones (2A–B) towards carbon steel corrosion in 1.0 M HCl was evaluated by molecular modeling, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) at different inhibitor concentrations. Polarization curves showed that all of the evaluated compounds acted as mixed inhibitors. EIS plots indicated that the presence of the inhibitors increases the charge transfer resistance of the corrosion process, increasing the inhibition efficiency. The adsorption of the evaluated inhibitors obeys the Langmuir adsorption isotherm. The theoretical results were corroborated by experimental data, with both the experimental and theoretical data showing that the thiosemicarbazones are better corrosion inhibitors than the semicarbazones.     

Effect of heat treatment on H2S corrosion of a micro-alloyed C–Mn steel

The H₂S corrosion resistance of a C–Mn pipeline steel with three different microstructures has been evaluated using electrochemical techniques with a 3% wt. NaCl solution at 50 °C. Microstructures included martensite, ferrite, and ferrite + bainite. Electrochemical techniques included potenthiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), and electrochemical noise (EN) measurements. Most of the tests lasted 24 h. All techniques showed that the highest corrosion rate corresponded to the steel with a martensitic microstructure; up to one order of magnitude higher than the corrosion rate for steels with a ferritic + bainitiic microstructure, whereas the steel with the ferritic microstructure showed the lowest corrosion rate. EIS tests showed that the corrosion process was under charge transfer control, whereas EN results indicated that the three steels exhibited a clear tendency towards a localized type of corrosion. However, for longer immersion times, the steel with a martensitic microstructure tended to exhibit a mixture of uniform and localized attack. Results were discussed in terms of grain size, grain boundary energy, amount and distribution of particles found in each steel.