H_2S-CO_2-Cl^-腐蚀环境单井集输管材选择

Selection of Single–well Gathering and Transferring Pipeline Material for H_2S-CO_2-Cl^- Environment

塔河油田腐蚀环境为H2S-CO2-Cl-体系,单井集输管道材质以20号钢为主,腐蚀穿孔严重。通过对BX245-1Cr、20号钢两种管材的室内实验和现场应用分析,采用了扫描电镜和激光共聚焦显微镜对BX245-1Cr与20号钢的腐蚀情况进行对比分析。室内实验分析表明,BX245-1Cr材质抗腐蚀能力优于20号钢,均匀腐蚀速率相比降低33.07%,点腐蚀速率相比降低30.05%。现场应用测试分析表明,BX245-1Cr点腐蚀速率明显低于20号钢点腐蚀速率,相比降低35.89%。通过对两种管材经济对比分析,选用管径为76 mm×5 mm的BX245-1Cr管材可节约1.44×104RMB$/km,选用管径为89 mm×5 mm的BX245-1Cr管材可节约1.34×104RMB$/km。

The corrosion environment in Tahe Oilfield is H2S - CO2 - C1-. Most of gathering and transferring materials for single -well gathering and transferring pipelines were 20# steel, and corrosion failure was serious. The BX245 - 1Cr and 20# steels were tested in the laboratory and field and analyzed ＆ compared by SEM and laser scanning. The lab tests showed that BX245 - 1Cr has better corrosion resistance than 20# steel, the uniform corrosion rate is 33.07% lower and the pit corrosion rate is reduced by 30.05%. The field tests demonstrated that the pit corrosion rate of BX245 - 1Cr steel is much lower than 20# steel. The reduction of pit corrosion rate is 35.89%. The economic analysis and comparison of two steel materials conclude that 14,400 Yuan/km can be saved by application of BX245 - 1Cr pipe materials with φ576mm × 5mm diameter, and 13,400 Yuan/km can be saved when BX245 - 1Cr pipe materials with φb89mm × 5 mm diameter are selected.