P110S钢在高矿化度油田水环空保护液中的腐蚀风险评价  

Corrosion risk assessment of P110S steel in annulus protection fluid in high salinity oilfield water

作　　者：黄知娟[1,2] 杜春朝[1,2] 龙武[1,2] 臧硕 刘振东 曾德智[3] Huang Zhijuan;Du Chunchao;Long Wu;Zang Shuo;Liu Zhendong;Zeng Dezhi(Petroleum Engineering Technology Research Institute of Sinopec Northwest Oilfield Company,Urumqi,Xinjiang,China;Sinopec Key Laboratory of Fracture-cave Reservoir Enhanced Oil Recovery,Urumqi,Xinjiang,China;State Key Laboratory of Oil&Gas Reservoir Geology and Exploration,Southwest Petroleum University,Chengdu,Sichuan,China)

机构地区：[1]中国石化西北油田分公司石油工程技术研究院 [2]中国石化缝洞型油藏提高采收率重点实验室 [3]油气藏地质及开发工程国家重点实验室·西南石油大学

出　　处：《石油与天然气化工》2021年第6期71-75,共5页Chemical engineering of oil & gas

基　　金：2020年中石化科研项目“顺北一区5号断裂带提质提速钻完井技术研究”(P20002)。

摘　　要：采用高矿化度油田水作为环空保护液基液易增加油套管钢腐蚀开裂的风险,因此,需对P110S钢在油田水环空保护液中的腐蚀风险进行评估。在对油田水和P110S钢的化学组分进行分析的基础上,用高温高压釜模拟现场工况,开展温度为200℃、CO_(2)分压为10 MPa、H_(2)S分压为2 MPa条件下的失重腐蚀和四点弯曲实验,并用SEM与EDS分析腐蚀产物形貌和成分,最后对试样进行截面分析。结果表明:P110S钢在高温高酸性工况下未发生应力腐蚀失效,腐蚀速率为0.0985 mm/a,试样表面存在严重的点蚀和局部腐蚀;截面分析显示试样表面腐蚀产物膜厚度为63μm,金属基体腐蚀严重,P110S油套管钢在此工况下面临较大的腐蚀失效风险。为了抑制管材的腐蚀,建议使用淡水或矿化度较低的井场水作为环空保护液基液。Using high-salinity oilfield water as the annulus protection liquid base fluid can easily increase the risk of corrosion and cracking of tubing and casing steel.Therefore,it is necessary to evaluate the corrosion risk of P110S steel in the oilfield water annulus protection liquid.Firstly,the chemical components of oil field water and P110S steel were analyzed.Then,the field conditions were simulated by using a high-temperature autoclave.The weightlessness corrosion and four-point bending experiments were carried out under the temperature of 200℃,CO_(2) partial pressure of 10 MPa and H_(2)S partial pressure of 2 MPa,and the morphology and composition of corrosion products was analyzed by using SEM and EDS.Finally,the cross-section of the sample was analyzed.The results show that P110S steel does not suffer from stress corrosion failure under high temperature and high acid conditions.The corrosion rate is 0.0985 mm/a,severe pitting and local corrosion can be observed on the surface of the sample.Cross-sectional analysis shows that the thickness of corrosion product film on the sample surface is 63μm,and the metal matrix is corroded seriously.P110S tubing and casing steel faces a greater risk of corrosion failure under this working condition.In order to suppress the corrosion damage of the pipes,it is recommended to use fresh water or low-salinity well site water as the annulus protection liquid base fluid.

关 键 词：酸性油气田 P110S钢 油田水环空保护液 腐蚀风险 

分 类 号：TE983[石油与天然气工程—石油机械设备]