生物酶可解堵钻井液的室内研究  

Study on the Degradation of Mud Cakes with Bio-enzymes

作　　者：杨倩云[1] 郭保雨[1] 沈丽[1] 袁丽[1] 秦涛[1] 

机构地区：[1]胜利石油管理局钻井工程技术公司

出　　处：《钻井液与完井液》2009年第6期1-4,共4页Drilling Fluid & Completion Fluid

基　　金：中国石油化工集团公司2006-2008年度基金项目<生物酶可解堵钻井液体系的研究>(JP06007)

摘　　要：用生物酶可解堵钻井液钻完井后不需要采用常规解堵技术,钻井液形成的泥饼能够在生物酶的作用下自动降解破除,且生物酶进入油层孔道后可以提高原油的流动能力,或改变液流方向,从而提高注入水波及体积,可提高油田采收率。该体系处理剂主要为纤维素、淀粉、生物聚合物、野生植物胶、多糖类聚合物等,在DO衰减法优选试验基础上对处理剂的降解性进行了再次评价,优选出6种主要组分,利用正交试验最终确定了体系最优配方。室内研究证明,该钻井液具有良好的流变性、润滑性(极压润滑系数不大于0.15)以及抑制性(相对10%KCl溶液,页岩膨胀量降低率为88.54%),抗温达120℃,并具有优良的油气层保护效果,渗透率恢复值大于90%。该体系能实现对地层无污染、无伤害钻进,完井后地层的渗透性恢复高,油气井产量大。现场应用也表明该技术油气层保护性能良好,提高了油气采收率。Bio-enzymes can be used to remove mud cakes after a well is completed.The bio-enzymes,when go into the pore throats,can improve the flowability of the crude oil,or change its flow direction,thus increasing the swept volume of injected water,and oil recovery.Using DO attenuation method,six additives were selected and the final optimized formulation was determined through orthogonal tests.Laboratory study showed that the formulated drilling fluid has good rheology,lubricity(EP friction coefficient is less than 0.15) and inhibitive capacity(shale swelling is reduced to 88.54% compared with 10% KCl solution).This fluid is stable at 120 ℃.Percent permeability recovery is as high as 90%.Field application also showed good results.

关 键 词：生物酶可解堵钻井液 生物降解 钻井液性能 防止地层损害 

分 类 号：TE254.3[石油与天然气工程—油气井工程]