CO_2驱注入井井筒完整性分析与风险评价

Integrity Analysis and Risk Assessment of Wellbore in CO_2 Flooding

针对CO_2驱油藏开发过程中注入井井筒完整性进行分析,将CO_2驱注入井井筒完整性评价分为井口、管柱及井筒三大单元,给出了井筒完整性评价指标,并利用层次分析法确定各完整性风险影响因素的权重。在此基础上,利用风险矩阵法建立CO_2驱注入井井筒完整性风险评价模型,确定注入井井筒完整性风险值和风险等级。利用以上方法对吉林油田某CO_2驱注气井井筒完整性进行评价,确定了井筒完整性主要风险因素和风险等级。研究结果表明:CO_2驱注入井井筒完整性风险评价有助于降低注入井安全事故风险,能够有效指导CO_2驱安全施工和完整性风险管理。

In the evaluation of wellbore integrity of CO2 flooding injection wells, the research object was divided into three units ：well- head, pipe string and wellbore. The wellbore integrity evaluation indexes were given, and the weights of all the integrit- influeneing factors were determined by AHP. The risk assessment model of wellbore integrity of CO2 flooding injection wells was established by using risk matrix method, and the risk values and risk grades of wellbore integrity of injection wells were determined. The wellbore integrity of a CO2 injection well in Jilin oilfield is evaluated using this method, and the main risk factors and risk level of wellbore integrity of the well were determined. The result shows that the wellbore integrity risk assessment of CO2 flooding injection well is helpful to reduce the risk of injection well safety accidents, and can effectively guide the safe operation and integrity risk management of CO2 flooding.