一种咪唑啉型缓蚀剂在榆林气田下古环境下的缓蚀行为

Corrosion Behavior of an Imidazoline Inhibitor in Xiagu Corrosion Environment of YULIN Gas-field

针对长庆榆林气田下古产水气井腐蚀环境在室内开发复配了一种水溶性咪唑啉类缓蚀剂;采用静态失重法、电化学法及扫描电子显微镜分析等研究此缓蚀剂在模拟下古腐蚀环境下的缓蚀行为,并确定缓蚀剂的最佳加量范围。结果表明:缓蚀剂取得了良好的缓蚀效果;缓蚀剂浓度大于100mg/L,腐蚀速率均小于0.076mm/a,缓蚀率大于90%。电化学方法与静态失重法的结论相一致且该缓蚀剂是以阴极控制为主的混合型缓蚀剂。通过扫描电镜可知,缓蚀剂在碳钢表面吸附成膜起到了良好的保护作用,随着缓蚀剂浓度增大,腐蚀减轻;此缓蚀剂的吸附状态是以化学吸附起主要作用的混合吸附。

According to the Xiagu Corrosion environment of YULIN gas-field to distribute a water-soluble imidazoline corrosion inhibitor in laboratory;using weight-loss method,electro-chemical method and scanning electron microscope(SEM)to study the corrosion behavior about the water-soluble imidazoline inhibitor of the Xiagu corrosive environment,and determine the best amount range of the corrosion inhibitor.The research results show that the corrosion inhibitor obtained the good effect Atmospheric corrosion tests,adding corrosion inhibitor more than 100 mg/L,the corrosion rate is less than 0.076mm/a,the corrosion inhibition rate is more than 90%;High-pressure corrosion test,adding corrosion inhibitor.The electro-chemical research got the same conclusion with the weightlessness method research,and this corrosion inhibitor is one of mixed type corrosion inhibitor which primarily controlled by negative pole.By scanning the electron microscope,the corrosion inhibitor got good protective function on the carbon steel surface with adsorption membrane;the corrosion is reduced with the increase of the inhibitor concentration.The adsorption state of the inhibitor is a mixed adsorption with chemical adsorption as the main function.