页岩储层压裂工艺技术在渝东地区应用

APPLICATION OF SHALE GAS RESERVOIR FRACTURING TECHNOLOGY IN EAST CHONGQING

页岩气的工业化开发要求对致密储层进行体积压裂改造,水平井多级分段压裂技术是成功开发页岩气藏的关键技术之一。页岩储层在地应力与致裂压力联合作用下突破页岩基质,沟通天然裂隙等弱结构面,形成高导流能力缝网系统,页岩储层中赋存的游离气和吸附气得以释放,提高了页岩气井的初始产量和最终采收率。根据渝东地区页岩储层工程地质特征,结合渝页A-2HF井、渝页B-2HF井矿场压裂施工数据,探索适用于渝东地区的页岩储层压裂工艺技术,结果表明,采用前置盐酸处理储层保持近井带导流能力,能够保障后续大排量施工压力窗口;低砂比粉砂段塞多级降滤实现"控近扩远",增加储层改造体积;压力异常层段胶液前置充分造缝,可为后续滑溜水携带支撑剂进入地层创造有利条件。

The industrial development of shale gas requires the volume fracturing of tight reservoir. Multilevel staged fracturing technique is one of the key techniques for the successful development of shale gas reservoirs. Shale reservoir,under the combined effect of in-situ stress and fracturing pressure,breaks through the shale matrix,and communicates with the weak structural plane of natural fracture,which forms a high conductivity network system.The release of free gas and adsorbed gas exists in shale reservoirs,improves initial shale gas production and ultimate recovery. According to the engineering geological characteristics of shale reservoir in east Chongqing,combined with Yuye A-2HF well and Yuye B-2HF well field fracturing construction data,this paper explores the suitable fracturing technology of shale reservoir in east Chongqing. The results show that the use of prehydrochloric acid treatment to keep the near well with diversion capacity,can protect the follow-up large displacement construction pressure window. Low sand ratio powder sand section of the multi-stage filter to achieve ＂controllednear and far＂,can increase the volume of the reservoir fracturing. Abnormal pressure layer glue front,made full hydraulic fracture,for the subsequent slickwater can carry proppant into the reservoir to create favorable conditions.