油气混输海底管道缓蚀剂评价研究及优化建议

Evaluation and optimization of corrosion inhibitors for subsea oil-gas pipeline

在反应釜中进行挂片腐蚀试验,利用质量损失法测试与海底管道相同材质的金属材料的腐蚀速率,研究在不同工况下缓蚀剂对海底管道的缓蚀效果。试验结果表明,不同工况下在高温高压模拟的海底管道中添加一定量缓蚀剂后,气相和液相缓蚀率均高于85%,腐蚀速率均低于0.0254 mm/a,为低度腐蚀。对比海底管道往年评价结果,评价数据差异较大,为验证差异原因,按照现场水质情况配制模拟水进行试验。试验结果表明,两次评价结果存在差异,而且主要源于现场水样中残存的缓蚀剂含量不同所致。提出取样间隔时间、药剂注入浓度和海底管道运行等方面的优化建议,以延长海底管道的运行寿命。

Coupon tests were conducted in the reactor,the corrosion rate of metal material of the same material as the submarine pipeline was tested by mass loss method,and the efficiency of corrosion inhibitors on the submarine pipeline was studied under different working conditions.The experimental results showed that when a certain amount of inhibitor was added to the submarine pipeline simulated by high-temperature and high-pressure environment at different working conditions,the corrosion inhibition rates of gas phase and liquid phase were both higher than 85%,and the corrosion rate was lower than 0.0254 mm/a,indicating low degree corrosion,which was greatly different from evaluation results of the submarine pipeline in previous years.In order to verify the reasons for the differences,simulation tests were carried out based on the water quality on site.The results showed that the variation was mainly due to the different content of residual inhibitor in the water samples.Furthermore,optimization suggestions in terms of sampling interval time,reagent injection concentration,as well as subsea pipeline operation were put forward to extend the operational life of the subsea pipeline.