大牛地气田碳酸盐岩储层复合酸压工作液体系优化研究  

THE OPTIMIZED RESEARCH OF THE WORKING FLUID SYSTEM ABOUT THE COMPOSITE ACID FRACTURING FOR CARBONATE RESERVOIR IN DANIUDI GAS FIELD

作　　者：邱小庆 QIU Xiao-qing

机构地区：[1]中石化华北油气分公司石油工程技术研究院

出　　处：《新疆石油天然气》2019年第3期69-73,8,共5页Xinjiang Oil & Gas

摘　　要：大牛地气田下古生界碳酸盐岩储层具有致密低渗、低压、低孔的特征,储层岩石弹性模量较高,泊松比低,酸蚀裂缝窄且长度有限,水平井酸压后整体稳产能力较差.为此,前期优化形成了复合加砂酸压工艺,取得了一定的改造效果.但复合加砂酸压工作液体系主要借鉴前期多级注入酸压工作液体系,没有进行系统研究.本文结合下古生界碳酸盐岩储层特征,针对复合加砂酸压工艺对工作液的要求,优化研究了酸液浓度、稠化剂浓度、前置液类型,形成了复合加砂酸压工作液,并研究了工作液对储层岩板的酸刻蚀情况及导流能力.优化后的工作液体系已完成复合砂酸压施工18井次173段,平均单井无阻流量较优化前提高1.4×104 m3/d,复合酸压取得了较好的改造效果,优化后的工作液将对致密低渗碳酸盐岩的开发提供可靠的技术保障.The lower paleozoic carbonate reservoir has the characteristics of low permeability,low pressure,lowporosity,high elastic modulus and low Poisson ratio,which could result in narrow acid etched fracture and limit-ed fracture length,and low production ability after the acid fracturing in horizontal well in Daniudi gas field. Inorder to solve this problem,the composite sand acid fracturing technology was optimized and formed early,whichachieved a certain effect. But the work fluid system of composite sand acid fracturing mainly referred to acidworking fluid system of the early stage of the multi-stage injection,and there is no systematic research. Combin-ing with the feature of reservoir,aiming at the requirement of the working fluid of the composite sand acid fractur-ing technology,the concentration of acid,the concentration of thickener,type of pad fluid were all optimized andresearched. The working fluid of the composite sand acid fracturing was formed,meanwhile the acid etching con-ditions and flow conductivity of reservoir rock plate about the working fluid were researched. Optimized workingfluid system was used successfully in 18 carbonate horizontal wells in Daniudi field. The single well averageopen-flow capacity was increased by 1.4×104 m3/d,and the composite acid fracturing achieved good effect. Theoptimized working fluid will provide reliable technical support for the development of the tight and low permeabil-ity carbonate.

关 键 词：低渗透 碳酸盐岩气藏 复合酸压 工作液 

分 类 号：TE357.2[石油与天然气工程—油气田开发工程]