致密砂岩交替注酸压裂工艺技术  

Alternate Acid Injection Fracturing Technology for Tight Sandstone Reservoirs

作　　者：刘建坤 蒋廷学[1,2] 吴春方 万有余[3] 刘世华 

机构地区：[1]页岩油气富集机理与有效开发国家重点实验室,北京100101 [2]中国石化石油工程技术研究院,北京100101 [3]中国石油青海油田分公司,甘肃敦煌736202

出　　处：《特种油气藏》2017年第5期150-155,共6页Special Oil & Gas Reservoirs

基　　金：国家科技重大专项“复杂地层储层改造关键技术”(2011ZX05031-004-003);中国石化科技攻关项目“鄂南致密油藏两级裂缝高导流复合压裂技术研究”(P17088)

摘　　要：为进一步扩大致密砂岩储层压裂有效改造体积,提高多尺度裂缝的复杂程度,结合压裂与酸化技术的优势,开展了交替注酸压裂技术研究。阐述了致密砂岩交替注酸压裂工艺的机理及作用;利用压裂裂缝模拟软件,对交替注酸模式及交替注入参数进行了正交模拟优化;结合储层特性及交替注酸压裂工艺要求,对交替注入段塞中的酸液及顶替液类型进行了优化。研究表明:前置液造缝缝长达到总设计缝长的70%左右时,即可进行多级交替注酸工艺;交替注酸泵注过程中,每级顶替排量以阶梯递增式注入、每级顶替液量按递减式注入、增大顶替液黏度及增加交替注入级数等方式,都有利于提高酸液在裂缝中的波及范围及均匀分布程度。现场试验表明,多级交替注酸压裂工艺压裂后增产及稳产效果显著高于常规改造工艺,可提高致密砂岩油气藏压裂有效性及改造效果。该技术可为致密砂岩储层的有效压裂提供技术支持。In order to improve the effective stimulated reservoir volume （ SRV ） in tight sandstone reservoirs and the complexity of mufti-scale fractures, alternate acid injection fracturing technology is investigated combining fractu- ring and acidificalion technology. The mechanism and function of alternate acid injection fracturing technology for tight sandstone is described ; fracturing simulation software is used for orthogonal optimization of alternate acid injec- tion mode and ahernate injection parameters ; the type of acid and displacement fluid in alternate injection plugs is optimized according to reservoir characteristics and the requirement for alternate acid fracturing technique. The re- search shows that multi-stage alternate acid injection technology can be used when the length of fractures induced by prepad fluid is 70% of the total designed length. During the alternate acid pumping, increasing displacement discharge rate for each stage, decreasing displacement fluid volume for each stage, increasing viscosity of displace- ment fluid and increasing alternate stages will improve the swept range and uniformity of acid fluid in fractures. The field tests showed that the stimulation and stage production effect of muhi-stage acid injection fracturing was signifi- cantly better than that of conventional stimulation technology and that this technology improved the fracturing effi- ciency and stimulation result in tight sandstone reservoirs. This technology provides technical support for effective fracturing in tight sandstone reservoirs.

关 键 词：致密砂岩 体积压裂 酸化 交替注入 裂缝复杂性 

分 类 号：TE357.1[石油与天然气工程—油气田开发工程]