CaCl_2型采出水对原油储罐底板的腐蚀影响分析  

Corrosion Perforation of CaCl_2 Produced Water to Bottom Plate of Crude Oil Storage Tank

作　　者：刘宇程[1] 张寅龙[1] 廖斯丞 徐俊忠[1] 

机构地区：[1]西南石油大学化学化工学院,四川成都610500

出　　处：《西南石油大学学报（自然科学版）》2014年第5期155-159,共5页Journal of Southwest Petroleum University(Science & Technology Edition)

摘　　要：针对吐哈油田原油储罐底部穿孔泄露影响油田正常生产及安全的问题,开展了腐蚀过程及影响因素分析研究。在原油储罐内进行现场挂片120 d后计算失重腐蚀速率,应用扫描电镜(SEM)分析腐蚀挂片表面的微观形貌,对储罐底部水溶液和储罐钢材进行成分分析,通过电化学方法研究了储罐钢的腐蚀过程,并测试Cl-和Ca2+对钢材的腐蚀速率影响。结果表明,挂片在罐底水溶液中出现不均匀的坑蚀,挂片失重速率为0.22 mm/a,电化学测试腐蚀速率为0.15 mm/a,瞬时腐蚀速率有增加趋势,碳钢表面出现二次钝化溶解现象,在罐底介质中Cl-和Ca2+的增加会加速腐蚀。为原油储罐底板腐蚀泄露的分析及治理奠定了基础。An analysis of process and influening factors in Tuha oilfield was made,aiming to solve the problems in oil production and safety issues caused by perforation leakage on tank bottom. After exposing coupons in the storage tank for 120 days,corrosion rate of weight loss was calculated. Scanning electron microscope（SEM）was employed to observe the microscopic corrosion morphology of coupons,and the composition of water and steel at the bottom of the storage tank were analyzed.The corrosion process was researched through electrochemical method and the influence of Ca^2＋ and Cl^- on corrosion rate was tested. The results show that the irregular pitting corrosion appears on the surface of coupons hung at the bottom of the storage tank. The corrosion rate of weight loss is 0.22mm/a and the corrosion rate tested by electrochemical method is 0.15mm/a. The instantaneous corrosion rate presents a trend of gradual increase. Repetitive passivation and solubility of surface film occurs on carbon steel. Ca^2＋ and Cl^- will accelerate corrosion in water solution in oil tank bottom. The research lays a foundation for analyzing and solving leakage of tank bottom.

关 键 词：原油储罐 底板 腐蚀穿孔 CACL2 电化学分析 

分 类 号：TE88[石油与天然气工程—油气储运工程]