新型防塌钻井液体系在苏丹六区储层的应用  

Application of a new anti-sloughing drilling fluid system in the Block 6 of Sudan

作　　者：张凤英[1] 鄢捷年[2] 林永学[1] 刘四海[1] 

机构地区：[1]中石化石油工程技术研究院,北京100101 [2]石油工程教育部重点实验室中国石油大学,北京102249

出　　处：《特种油气藏》2010年第5期103-106,共4页Special Oil & Gas Reservoirs

基　　金：国家自然科学基金项目"低孔低渗油气储层损害机理及有效保护方法研究"(50974129);国家科技部国际合作研究项目"苏丹油田重点区块保护储层的钻井液完井液技术研究"(2008KR0421)的部分研究成果

摘　　要：针对苏丹油田六区储层钻井过程中易于发生井壁失稳、扩径、缩径、取心效率低及起下钻阻卡等井下事故问题,结合苏丹六区储层岩性、孔隙、孔喉及渗透率的特点,基于"理想充填理论"和成膜技术,对具有不同粒径的暂堵剂产品按一定比例进行合理的复配组合,形成了1种新型低伤害防塌钻井液体系,并应用于苏丹六区。实验结果表明,原用钻井液对岩心损害较为严重,新型钻井液所用处理剂均对环境无污染,处理剂没有荧光,钻屑具较好代表性,且容易清洗,能明显提高岩心渗透率恢复值,且可降低钻井液的动滤失量,能有效阻止钻井液中固相颗粒和滤液侵入油气层,满足苏丹六区安全、快速、经济钻井的要求,在钻遇Aradeiba页岩地层过程中得到了成功的应用,具有十分理想的储层保护效果。Downhole accidents such as borehole instability,hole enlargement,hole shrinkage,low coring efficiency and tripping problem are often seen during drilling process in the Block 6 of Sudan. Based on 'ideal packing theory' and membrane-forming technology,a new low damage anti-sloughing drilling fluid system has been developed and applied in the Block 6 of Sudan by blending temporary plugging agents of different grain sizes in certain proportion according to reservoir lithology,aperture,pore throat and permeability. Experiment result shows that the original drilling fluid has severely damaged the core; the new drilling fluid uses treatment agents uncontaminated to environment and without fluorescence,and the cuttings are better representative and easy to clean. The new drilling fluid can significantly improve the return permeability of core sample,reduce the dynamic filtration rate,effectively prevent solid particles and filtrate from entering reservoir,and meet the requirements of safe,fast and economic drilling in the Block 6,Sudan. This new drilling fluid system has been successfully used in drilling the Aradeiba shale formation and achieved very satisfactory effect of reservoir protection.

关 键 词：理想充填理论 成膜技术 暂堵剂 渗透率 钻井液 储层保护 苏丹六区 

分 类 号：TE254[石油与天然气工程—油气井工程]