CO2驱提采技术因其诸多优点得到了广泛应用,但同时也带来了严重的地面采输系统腐蚀结垢风险。为此,分别采用电化学测试方法和静态阻垢法对油田常用的缓蚀剂和阻垢剂进行筛选,对优选的缓蚀剂和阻垢剂进行配伍性和协同性测试后,复配出效果优异的复合缓蚀阻垢剂,最后采用失重法和模拟工况阻垢率测试评价复合缓蚀阻垢剂的综合防护性能。筛选出的缓蚀剂和阻垢剂在55 ℃、常压下,饱和CO2的模拟地层水中对采输系统典型钢材20钢的缓蚀率达93.06%,阻垢率达95.18%;将筛选的缓蚀剂和阻垢剂复配后,在模拟工况下,复合缓蚀阻垢剂加量500 mg/L时20钢的腐蚀速率控制在0.045 mm/a以内,阻垢性能满足油田控制指标。研究结果表明,复配的复合缓蚀阻垢剂对CO2驱地面采输系统具有较好的防护作用,能保证其安全运行和生产。

The EOR technology of CO₂ flooding is increasingly used because of its advantages, but it is also accompanied by the high risk of corrosion and scaling in the surface production and transportation system. As a result, this study was carried out using the electrochemical test method and the static scale inhibition method to evaluate and select corrosion and scale inhibitors commonly found in oil field. After the compatibility and synergy test of the corrosion and scale inhibitor, the most effective compound inhibitor was prepared. Finally, the comprehensive protection performance of the compound inhibitor was evaluated by weight loss method and scale inhibition rate test under simulated condition. The experimental results showed that: the corrosion inhibition rate of the selected corrosion inhibitor and scale inhibitor in the simulated formation water of saturated CO₂ at 55 ℃ and atmospheric pressure is 93.06% and scale inhibition rate is 95.18% for the typical 20 steel used in the production and transportation system. After mixing together the selected corrosion inhibitor and scale inhibitor, the corrosion rate of the 20 steel is controlled within 0.045 mm/a when the amount of the composite corrosion and scale inhibitor is injected at 500 mg/L under the simulated condition. The scale inhibition rate is 93.91%, which can meet the performance indicators of oil field. The results showed that the compound corrosion and scale inhibitor can play a good role in protecting the production and transportation system of CO₂ flooding facilities, and guarantee the safe operation and production activities.