页岩气藏压裂前水化预处理工艺先导试验  

Pilot Test of Hydration Pretreatment before Fracturing in Shale Gas Reservoir

作　　者：朱炬辉 梁兴 曾晶 耿周梅 吴凯 张俊成 邹龙庆 ZHU Juhui;LIANG Xing;ZENG Jing;GENG Zhoumei;WU Kai;ZHANG Juncheng;ZOU Longqing(Dounhole Service Company,CNPC Chuanqing Drilling Engineering Company Limited,Chengdu,Sichuan 610051,China;PetroChina Zhejiang Oilfield Company,Hanghou,Zhejiang 310013,China)

机构地区：[1]中国石油川庆钻探工程有限公司井下作业公司 [2]中国石油浙江油田分公司

出　　处：《钻采工艺》2022年第1期65-69,共5页Drilling & Production Technology

基　　金：国家重大专项“大型油气田及煤层气开发”项目“昭通页岩气勘探开发示范工程”课题4“山地页岩气储层体积压裂增产改造技术现场试验与应用”(编号:2017ZX05063004-014);中国石油集团项目“井下光纤智能监测技术现场试验”(编号:2020F-44)。

摘　　要：页岩气藏进行体积压裂后,大量压裂液侵入地层与储层发生水化作用,对压裂改造产生影响,开展页岩水化作用的研究具有重要意义。以提升压裂缝网复杂度为目的,文章提出了一种页岩气藏压裂前的清水水化预处理工艺,泵注一定量清水对即将压裂的层段进行浸泡,并开展了四川盆地页岩气水平井水化预处理工艺的现场试验。压裂前水化预处理使压裂初期的地层破裂点普遍多于相邻未水化处理的层段,结合储层最小水平主应力分析,水化层段延伸压力相对于邻段较低。前期室内岩心水化实验和现场水化处理结果显示,页岩储层通过水化预处理可以在一定程度上诱导储层内部空间产生变化,改变压裂前地层原有的孔隙结构,从而改变破裂压力与破裂特征,对页岩气储层改造的裂缝复杂度提升具有重要的参考意义。After stimulated reservoir volume fracturing in shale gas reservoir, a large amount of fracturing fluid invades into the formation and has hydration with the reservoir, which has an impact on fracturing stimulation. The research on shale hydration is of great significance. In order to improve the complexity of fracture network, this paper puts forward a water hydration pretreatment process before fracturing of shale gas reservoir which is by pumping a certain amount of water to soak the fracturing stages, and carries out the field test of hydration pretreatment process of shale gas horizontal wells in Sichuan Basin. The hydration pretreatment before fracturing makes the formation fracture points at the initial stage of fracturing generally more than the adjacent untreated intervals. Combined with the analysis of minimum horizontal principal stress of the reservoir, the extension pressure of the hydrated interval is lower than that of the adjacent interval. The results of field and indoor experiments show that the hydration pretreatment of shale reservoir can induce changes in the internal space of the reservoir to a certain extent, change the original pore structure of the formation before fracturing, so as to change the fracture pressure and fracture characteristics, which has important reference significance for improving the fracture complexity of shale gas reservoir reconstruction.

关 键 词：页岩气 压裂 水化作用 预处理 清水 

分 类 号：TE377[石油与天然气工程—油气田开发工程]