川南长宁区块页岩气高密度完井+高强度加砂压裂探索与实践  

Exploration and Practice on Combination of High-density Completion and High-intensity Sand Fracturing in Shale Gas Horizontal Well of Changning Block in Southern Sichuan Basin

作　　者：郑有成[1] 赵志恒 曾波[2] 宋毅[2] 郭兴午 黎俊峰 ZHENG Youcheng;ZHAO Zhiheng;ZENG Bo;SONG Yi;GUO Xingwu;LI Junfeng(PetroChina Southwest Oil&Gas Field Company,Chengdu,Sichuan 610051,China;Shale Gas Research Institute,PetroChina Southwest Oil&Gas Field Company,Chengdu,Sichuan 610051,China)

机构地区：[1]中国石油西南油气田分公司 [2]中国石油西南油气田分公司页岩气研究院

出　　处：《钻采工艺》2021年第2期43-48,共6页Drilling & Production Technology

基　　金：中国石油西南油气田分公司科技项目“页岩气水平井段内多簇压裂优化设计研究”(编号:20190302-18)。

摘　　要：四川盆地南部长宁区块页岩气资源量丰富,经过技术引进、探索优化、自主创新实现了规模开发。为了进一步提高近井筒储层改造效果、提升作业效率,对水平井分段不断优化,适当增加分段段长,减少压裂段数,同时采用高密度完井,大幅缩短簇间距,并持续提高加砂强度。为此以高密度完井+高强度加砂压裂技术原理为基础,根据长宁区块地质工程特征对该压裂工艺参数进行了探索优化,并分析了该压裂技术的现场应用效果。研究结果表明,高水平应力差页岩储层条件下,高密度完井+高强度加砂压裂技术可利用短簇距间的诱导应力增加裂缝复杂程度,缩短储层基质流体向裂缝渗流的距离和时间,并提高裂缝导流能力;考虑簇间诱导应力对裂缝扩展的影响,施工排量、压裂液黏度对井间储层动用程度和裂缝支撑的影响,暂堵转向技术对压裂裂缝体积的影响等,合理优选出与长宁区块地质和工程条件相匹配的压裂参数:簇间距7~10 m,施工排量约16 m3/min,携砂阶段滑溜水黏度增加到20~30 mPa·s,单段暂堵剂300~500 kg,总液量的50%~57%投注;长宁区块页岩气水平井采用高密度完井+高强度加砂压裂技术,井均测试产量较常规压裂工艺增加了约10%,估计最终可采量可提高约12%。该研究成果可为压裂技术持续优化以及川南地区页岩气藏压裂改造提供支撑和借鉴。There are huge shale gas resources in Changning Block located in the Southern Sichuan Basin.Through technology introduction,exploration optimization and independent innovation,it has realized large-scale development.In order to improve treatment effectiveness of near-wellbore formation and operation efficiency further,stage length was increased to reduce the number of stages,and high-density completion was introduced to shorten cluster spacing,and the amount of proppant was increased intensively.Therefore,based on the mechanism of high-density completion and high-intensity proppant injection fracturing technology,fracturing parameters were optimized on account of the geology characteristics of Changing Block,and the application effect was analyzed.The research results show that in the shale formation with high horizontal stress difference,high-density completion and high-intensity proppant injection fracturing technology could improve fracture complexity due to the induced stress between clusters,and shorten the distance and time of fluid flowing from shale matrix to fractures,and increase the fracture conductivity.Accordingly,the effect of induced stress between clusters on fracture propagation,the effect of flow rate and fracture fluid viscosity on interwell reservoir productivity and propping of fractures,and the effect of temporary plugging diversion on fracture volume,there are reasonable and optimized fracturing parameters that match the characteristics of geology and engineering of Changning Block.The cluster spacing is 7-10 m,flow rate is about 16 m3/min,slick water viscosity increases to 20-30 mPa·s during proppant injection,and 300-500 kg diversion agent is used during 50%-57%of total fracturing fluid.Besides,the high-density completion and high-intensity proppant injection fracturing technology is employed in Changning Block.Compared with conventional fracturing,the average tested production has increased by 10%and the estimated ultimate recovery has increased about 12%.The study results could support

关 键 词：页岩气 长宁区块 高密度完井 高强度加砂 参数优化 应用效果 

分 类 号：TE377[石油与天然气工程—油气田开发工程]