苏77、召51区块缓蚀剂评价与机理研究

Study on Evaluation and Mechanism of Corrosion Inhibitors in SU 77 and ZHAO 51 Blocks

针对苏77、召51区块N80油套管钢出现的腐蚀穿孔问题,利用高温高压模拟实验和电化学极化曲线法研究了RX-204B和IMC-80BH等两种常用缓蚀剂的作用机理及防腐效果。通过扫描电镜对去除腐蚀产物前后的试样表面形貌进行观察;采用能谱分析仪对腐蚀产物进行成分分析。结果表明:两种缓蚀剂均为吸附膜阳极控制型缓蚀剂,由于成分不同,官能团的作用机理不同,不同浓度下两种缓蚀剂的极化曲线变化规律存在一定差异。明确了两种缓蚀剂的腐蚀机理及最佳加注浓度,形成了适用于苏77、召51区块气井井筒工况的最优防腐工艺。

Aiming at the corrosion perforation problem of N80 oil casing steel in Su 77 and Zhao 51 blocks,the effect mechanisms and anti-corrosion effects of RX-204B and IMC-80BH corrosion inhibitors was studied by high temperature and high pressure simulation test and electrochemical polarization curve method.The surface morphology of the samples before and after the removal of corrosion products was observed by SEM.The composition of the corrosion products were studied by energy spectrum analyzer.The results show that both corrosion inhibitors are anode-controlled corrosion inhibitors with adsorption membranes.Due to different composition,the mechanism of action of functional groups is different.There are some differences in the polarization curves of the two corrosion inhibitors at different concentrations.Finally,the corrosion mechanism and optimal filling concentration of the two corrosion inhibitors are explicit.In addition,the optimal anti-corrosion process for SU 77 and ZHAO 51 block gas well appears.