改性聚乙醇酸暂堵剂研发及其在河南油田的应用  

Research and development and application of PGA modified temporary plugging agent

作　　者：冯兴武[1,2] 刘正奎 郑桐[1,2] 尹晓静 杨琪[1,2] 段军 FENG Xinwu;LIU Zhengkui;ZHENG Tong;YIN Xiaojing;YANG Qi;DUAN Jun(Petroleum Engineering Technology Research Institute of Henan Oilfield Company,SINOPEC,Nanyang 473000,Henan,China;Henan EOR Key Laboratory,Nanyang 473000,Henan,China)

机构地区：[1]中国石化河南油田分公司石油工程技术研究院,河南南阳473000 [2]河南省提高石油采收率重点实验室,河南南阳473000

出　　处：《石油地质与工程》2024年第3期23-28,共6页Petroleum Geology and Engineering

基　　金：中国石油化工股份有限公司“高温高盐油藏注水开发用功能型聚合物研制与应用”(股份421089-2)。

摘　　要：酸溶性暂堵剂对地层伤害较大,解堵较麻烦,油溶性暂堵剂不适合高含水的油层;河南油田低渗透油藏地层温度为50~120℃,注水驱油见水快,常规水溶性聚乙醇酸暂堵剂和聚乳酸暂堵剂水解温度大于80℃,不能完全满足低渗透油藏暂堵压裂的需求。结合颗粒类水溶性聚乙醇酸暂堵剂和聚乳酸暂堵剂的特性和暂堵原理,采用催化剂和抑制剂使聚乙醇酸和聚乳酸发生酯化反应,生成聚乙醇酸和聚乳酸融合物,再加入成核剂及结晶促进剂,可得到改性聚乙醇酸暂堵剂。经测试,改性聚乙醇酸暂堵剂在50~120℃温度下具有常规聚乙醇酸暂堵剂的溶解性能和暂堵强度;当改性聚乙醇酸暂堵剂的总用量占比达到18%、粗粒径与细粒径质量配比接近1:1时,其封堵强度大于40 MPa,暂堵性能良好。现场试验7井次,加入改性聚乙醇酸暂堵剂后,单井施工压力最高增加了6.1 MPa,日增油5.3 t,取得了明显的增油效果。The acid soluble temporary plugging agent is more damaging to the formation and difficult to solve,while the oil soluble is not suitable for the oil reservoir with high water content.The temperature of low-permeability reservoirs in Henan Oilfield is 50 to 120℃,and water flooding occurs quickly,and conventional water-soluble hydrolysis temperature of polylactic acid(PLA)and polyglycolic acid(PGA)is greater than 80℃,which cannot fully meet the needs of temporary plugging and fracturing of low permeability reservoirs.By combining the characteristics and temporary plugging principles of particulate PLA and PGA,catalysts and inhibitors are used to cause esterification reaction between polyglycolic acid and polylactic acid,generating a fusion of polyglycolic acid and polylactic acid.By adding nucleating agents and crystallization promoters,a modified polyglycolic acid temporary plugging agent can be obtained.The test results show that the modified polyglycolic acid temporary plugging agent has the solubility and temporary plugging strength of conventional polyglycolic acid temporary plugging agent at 50~120℃.When the total dosage of polyglycolic acid modified temporary blocking agent reaches 18%,and the dosage of coarse and fine temporary blocking agents is close to 1:1,the temporary blocking strength is greater than 40 MPa,and the temporary blocking performance is good.In the field test of 7 wells,after adding temporary plugging agent,the maximum construction pressure of single well increased by 6.1 MPa,the daily oil increase was 5.3 t,and an obvious oil increase effect has been achieved.

关 键 词：暂堵剂 转向压裂 聚乙醇酸 水溶性 暂堵强度 

分 类 号：TE357[石油与天然气工程—油气田开发工程]