碳酸盐岩储层高酸溶多级架桥暂堵型钻井完井液体系  

A Temporary Plugging Drill-in Fluid with Highly Soluble Multilevel Bridging Particles for Carbonate Reservoir

作　　者：高伟[1] 范胜 齐彪 代昌楼 贾虎 牛骋程 GAO Wei;FAN Sheng;QI Biao;DAI Changlou;JIA Hu;NIU Chengcheng(Research Institute of Petroleum Engineering,SINOPEC Northwest Company of China Petroleum and Chemical Corporation,Urumqi,Xinjiang 830011;School of Petroluem Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500)

机构地区：[1]中国石化西北油田分公司石油工程技术研究院,乌鲁木齐830011 [2]西南石油大学石油与天然气工程学院,成都610500

出　　处：《钻井液与完井液》2024年第5期589-602,共14页Drilling Fluid & Completion Fluid

基　　金：霍英东教育基金会第十七届高等院校青年教师基金“离子液体纳米复合凝胶的构筑及堵水堵漏机理研究”(171043);四川省区域创新合作项目“准噶尔盆地南缘深层油气藏钻完井离子液体凝胶堵漏机理研究”(2020YFQ0036)。

摘　　要：以顺北二区碳酸盐岩储层为研究对象,通过岩心裂缝稳定性校正评价了储层敏感性,开展了现用钻井液伤害评价,明确了储层损害主控因素为应力敏感伤害和固相伤害,2种伤害因素累计占比达78.07%。采取“钻井可暂堵、完井可解堵”理念和保护微裂缝为主的储层保护思路,根据裂缝架桥封堵理论,研选了高酸溶固相封堵材料耦合可降解纤维关键材料。通过抗温、抗盐抗钙、沉降稳定性、配伍性及储层保护性能评价,形成了耐高温180℃多级架桥储层保护钻井完井液体系,其承压超过10 MPa,酸化后渗透率恢复率均值可达96.86%,相对常规不含酸溶暂堵材料体系提高了16.23%,具有强封堵、高返排的特点,有望减轻顺北二区碳酸盐岩储层的损害。The sensitivity of the carbonate reservoir in the second block of the Shunbei oilfield is evaluated through rock fracture stability correction method.In the evaluation drilling fluid samples taken from operational field were used and the results of the evaluation show that the main factors causing reservoir damage are stress sensitivity and solids invasion;the damage to the reservoir caused by these two factors totals 78.07%.In laboratory study,the idea of“temporarily plugging the reservoir during drilling and the plugging agents can be removed in well completion”was adopted in drilling fluid design,and the microfractures in the reservoir rocks are intentionally protected with the plugging agents.According to the theory of bridging and plugging the microfractures,plugging agents that are highly acid soluble and fibers that are degradable are selected as the key additives working together to plugging the microfractures.Using these plugging agents,a drill-in fluid capable of plugging the microfractures in the reservoir through multiple bridging is formulated.The performance of the drill-in fluid in resisting high temperatures and salt and calcium contamination as well as the settling stability,compatibility and reservoir protection property are evaluated.The results show that the drill-in fluid works normally at temperatures up to 180℃,the pressure bearing capacity of the layers formed by the solids of this drill-in fluid exceeds 10 MPa,the permeability recovery after acid job is 96.86%,an increase by 16.23%over conventional drill-in fluids containing no acid soluble temporary plugging agents.This drill-in fluid has strong plugging capacity the high rate of flowback characteristics,and is expected to alleviate the formation damage in the second block in Shunbei oilfield.

关 键 词：碳酸盐岩 微裂缝 稳定性校正 可酸溶 封堵 钻井完井液 超低伤害 

分 类 号：TE258[石油与天然气工程—油气井工程]