生物酶完井液的研究及在低渗油气田的应用

Research on Biologic Completion Fluid and It’s Application in Low Permeability Oil Gas Fields

于雷 张敬辉 李公让 张虹 李斌

Yu Lei Zhang Jinghui Li Gongrang Zhang Hong Li Bin

中国石化胜利石油管理局钻井工艺研究院, 山东东营 257017

Drilling Technology Research Institute, Shengli Petroleum Administration, Sinopec, Dongying, Shandong, 257017, China

非射孔完井水平井的滤饼堵塞是影响油井产量的重要因素,利用生物酶降解聚合物是清除滤饼的一种重要手段。通过室内试验优选了酶的种类和酶的质量分数,考察了pH值对酶解过程的影响,并分析了生物酶降解聚合物的机理。以疏水缔合聚合物AX-1为生物完井液的增黏剂,通过正交试验确定了生物完井液的配方。对研制的生物酶完井液进行了钻井液黏度降低率评价、浸泡滤饼试验和油层保护试验。试验结果表明,生物酶对聚合物具有较强的降解作用,生物酶完井液清除滤饼效果良好,渗透率恢复率均达到85%以上,具有良好的油层保护能力。现场应用表明,生物酶完井液具有良好的解堵作用,可以显著提高低渗油气田的单井产量。选择合适的生物酶可以有效清除不同钻井液的滤饼,提高油气层保护效果。

Filter cake blockage is an main factor influencing oil well production in horizontal wells with non-perforation completion,and degrading polymer with biologic enzyme is a major way to clear filter cake.The kind and concentration of enzyme were defined through lab experiment.At the same time,the influence of pH on enzyme degrading course was investigated,and the mechanism of biologic enzyme degrading polymer was analyzed.Hydrophobic association polymer AX-1 was selected as the viscofier of biologic completion fluid,and its formula was formed through orthogonal experiment.Reduced rate of viscosity,filter cake soaking and formation protection tests were conducted for the fluid.Experiment results show that the biologic completion fluid clears filter cake well and recovery of permeability is over 85%,which result in good reservoir protection.Field application in Shengli Oilfield and Daniudi Gas Field shows that the biologic completion fluid can remove plugging effectively and enhance production significantly in low permeability reservoirs.For different drilling fluids,appropriate biologic enzyme can clear filer cake effectively and improve formation damage control.

国家科技重大专项"低渗油气田高效开发钻井技术"课题4"低渗油气田储层保护技术"(编号:2008ZX05022-004)部分研究成果

https://doi.org/10.3969/j.issn.1001-0890.2012.03.007