一种油田用咪唑啉缓蚀剂缓蚀效果评价

为了评价某区块油田在用的一种咪唑啉缓蚀剂的缓蚀性能，对J55钢在模拟工况环境中进行了腐蚀速率测试试验。通过失重法计算均匀腐蚀速率，采用EDS、XRD、SEM技术分析其腐蚀产物组分和微观形貌，用金相显微镜测量点蚀坑深度并计算点蚀速率。结果显示，该区块以CO2腐蚀为主，腐蚀产物含有FeCO3；在添加不同浓度咪唑啉衍生物类缓蚀剂时，试样表面均以均匀腐蚀为主，但表面有不同程度的点蚀坑。失重法计算结果表明，在模拟工况腐蚀条件下，该缓蚀剂对J55钢具有良好的缓蚀效果，缓蚀率随着缓蚀剂浓度增大而提高；当缓蚀剂浓度为120 mg/L时缓蚀率最高，J55钢的均匀腐蚀速率仅为0.028 1 mm/a，试样表面未见明显点蚀，该浓度下咪唑啉缓蚀剂具有最佳的缓蚀效果。

Evaluation of Corrosion Inhibition Effect of An Imidazoline Inhibitor in Oilfield

In order to evaluate the corrosion inhibition performance of imidazoline corrosion inhibitor used in a regional oilfield， the corrosion rate of J55 steel were tested in simulated working condition was carried out. The uniform corrosion rate was calculated by weight loss method. The components and micro-morphology of corrosion products were analyzed by EDS，XRD and SEM. And the pitting depth and pitting rate were measured by metallographic microscope. EDS and XRD results showed that the corrosion product contained FeCO3， and the corrosion mode in this area was mainly CO2 corrosion. SEM results showed that the surface of the sample was mainly uniform corrosion at different corrosion inhibitor concentrations， but there were pitting pits at different degrees. The results of weight loss method showed that the corrosion inhibitor had good corrosion inhibition effect on J55 steel under simulated oilfield test conditions， and the corrosion inhibition efficiency increased with increasing concentration. However， when the corrosion inhibitor concentration was 120 mg/L， the corrosion inhibition rate was the highest， and the uniform corrosion rate of J55 steel was only 0.028 1 mm/a. There is no obvious pitting on the surface of the sample. Therefore， the imidazoline corrosion inhibitor has the best corrosion inhibition effect at this concentration.