通过高温高压动态反应釜研究了温度、H₂S分压、流速对L80钢H₂S腐蚀行为的影响,对腐蚀产物进行SEM和EDS元素分析,优选了耐高温的H₂S缓蚀剂LH-11,并对其缓蚀性能进行研究。结果表明:L80钢的H₂S腐蚀速率在80℃达到最大值,在140℃达到最小值;L80钢的腐蚀速率随H₂S分压的升高而增大,随流速的增大逐渐增大,腐蚀产物主要为硫铁化合物,结构疏松不规则,且有孔隙。缓蚀剂LH-11对L80钢的缓蚀率可达到87.05%,耐温180℃;添加缓蚀剂后,L80钢的腐蚀速率可降至0.1 mm/a以内,该缓蚀剂适用于不同H₂S分压和不同流速条件,可对热采管柱起到较好的保护作用。

The effects of temperature, H₂S partial pressure and flow rate on the H₂S corrosion behavior of L80 steel were studied by using a high temperature and high pressure dynamic autoclave, and the corrosion products were analyzed by SEM and EDS. The high temperature resistant H₂S corrosion inhibitor LH-11 was selected to study its corrosion inhibition performance. The results showed that the H₂S corrosion rate of L80 steel reached the maximum at 80 ℃ and the minimum at 140 ℃; the corrosion rate of L80 steel increased with the increase of H₂S partial pressure, and gradually increased with the increase of flow rate. The corrosion products were mainly sulphur-iron compounds with loose and irregular structure and pores. The corrosion inhibition rate of the corrosion inhibitor LH-11 to the steel could reach 87.05%, and the temperature resistance was 180 ℃. After adding the corrosion inhibitor, the corrosion rate of the steel could be reduced to less than 0.1 mm/a. The corrosion inhibitor was suitable for different H₂S partial pressure and different flow rate conditions, and could play a good role in protecting the thermal recovery string.