气基流体欠平衡钻井腐蚀/冲蚀研究现状及进展

STATUS QUO AND ACHIEVEMENT MADE IN CORROSION/EROSION BEHAVIOR STUDY FOR GAS-BASED FLUID DRILLING

气基流体欠平衡钻井包括纯气体钻井、雾化钻井、泡沫钻井和充气钻井。目前国内的气基流体钻井主要以提高钻速、防漏堵漏和保护储层为出发点,较少考虑气基流体钻井中出现的腐蚀/冲蚀特点及其危害。国外对气基流体欠平衡钻井中的腐蚀已引起足够重视,并采取了化学法、非化学法、非欠平衡为主的3种方法加以解决。为此,综述了国内外在实施气基流体欠平衡钻井中遇到的腐蚀/冲蚀实例、机理及预防措施,目的是预防欠平衡钻井腐蚀/冲蚀发生,确保气基流体欠平衡钻井的安全可靠,为该技术在国内油气田合适地层的推广提供技术支撑。同时建议除加强对其腐蚀/冲蚀交互作用机理研究外,还应加快缓蚀剂开发和井口监测装置的研制。

Underbalanced gas-based fluid drilling is classified into straight gas drilling, mist drilling, foam drilling and aerated drilling. Currently in China the gas-based fluid drilling starts at improving ROP, lost circulation control, and reservoir protection, study is rarely done on corrosion/erosion behavior occurred in gas-based fluid drilling. While in foreign countries focus has been on the corrosion behavior, chemical method, non-chemical method, non-UBD method have been the major solution. Herein corrosion/erosion cases encountered at home and abroad are introduced, and also the mechanism and preventive measures adopted. The purpose is to prevent occurrence of corrosion and erosion during UBD, to ensure safe gas drilling by providing technical support for widespread application in domestic oil and gas fields. Besides study on interaction of corrosion and erosion, it is recommended to quicken the development of inhibitors and wellhead monitoring devices.