CO_2驱高温高盐油藏井筒用P110套管的腐蚀规律

Corrosion Rules of P110 Casing for Carbon Dioxide Flooding of High Temperature and Salinity Reservoir

研发了生产系统多相流二氧化碳腐蚀仿真模拟装置,通过模拟注入井、采出井和地面集输管道的多相流状态腐蚀环境,实现多种流态、不同CO_2分压与温度条件下的材料腐蚀评价和缓蚀剂性能评价。在此基础上,研究了矿化度、温度、CO_2分压和流速等多种腐蚀因素对CO_2驱生产井中P110套管的腐蚀影响规律,建立了高CO_2分压局部腐蚀预测模型,并绘制CO_2驱采出井管材局部腐蚀预测图板。结果表明:CO_2驱采出井中P110套管的关键防腐蚀部位为高CO_2分压采出井、井筒中下部、动液面附近管柱。现场应用结果表明,该预测图板的预测符合率达到了80%,能快速、准确预测井筒的腐蚀规律与腐蚀情况。

A multi-phase flow carbon dioxide corrosion simulation device for production systems was developed.By simulating the multi-phase flow state corrosion environments of injection wells,production wells and ground gathering pipelines,the corrosion assessment and corrosion inhibitor performance evaluation of materials under conditions of various fluid states and different CO2 partial pressures and temperatures were realized visually.On this basis,the effects of various corrosion factors such as salinity,temperature,CO2 partial pressure and flow rate on the corrosion of P110 casing in CO2 flooding production wells were studied.A high CO2 partial pressure localized corrosion prediction model was established,and a localized corrosion prediction map of the CO2 flooding well pipe was drawn.The results show that the key anti-corrosion parts of the P110 casing in the CO2 flooding well were：high CO2 partial pressure production well,middle and lower parts of the wellbore,and pipe column near the hydrodynamic surface.The field application results show that the prediction board achieves a prediction coincidence rate of 80%,which can quickly and accurately predict the corrosion law and corrosion situation of the wellbore.