原油与高压CO_2共存条件下咪唑啉缓蚀剂的作用行为研究

Inhibition Behavior of Imidazoline Inhibitor in Corrosive Medium Containing Crude Oil and High-Pressure CO_2

采用动态失重挂片、高温高压电化学测试、接触角测试及扫描电镜等手段,在80℃、2.5 MPaCO_2条件下模拟饱和CO_2油田采出水,研究原油与高压CO_2共存条件下咪唑啉缓蚀剂对N80钢的缓蚀作用。结果表明:在含有咪唑啉缓蚀剂的腐蚀介质中加入原油后,电极的开路电位有所增加,电极的电荷传递电阻显著变大,碳钢对水的润湿性明显降低,缓蚀剂在金属表面覆盖更完整,原油显著增强了咪唑啉缓蚀剂的缓蚀性能。

Effect of crude oil on the inhibition behavior of imidazoline inhibitor were illustrated by dynamic mass loss method,electrochemical test,contact angle measurement,scanning electron microscopy etc.The oilfield produced water was simulated in the presence of CO2 under pressure of 2.5 MPa at 80 ℃,then in the above corrosive medium the corrosion inhibition performance of imidazoline corrosion inhibitor for N80 steel was assessed.The results showed that the open circuit potential and charge transfer resistance of the carbon steel increased when adding crude oil into the corrosive medium which contained imidazoline corrosion inhibitor.It is also found that the wettability of carbon steel surface against water was reduced obviously and the coverage of the inhibitor film became more complete,whilst the inhibition efficiency increased greatly after introducing crude oil into the oilfield produced water.