冀东低渗透油藏降压增注剂的性能评价与应用

Performance Evaluation and Application of Pressure-lowering and Injection-increasing Agent in Low Permeability Reservoir of Jidong Oilfield

刘 京 刘 彝 李良川 王金忠 张 霞 唐 聪

LIU Jing LIU Yi LI Liangchuan WANG Jinzhong ZHANG Xia TANG Cong

针对冀东高尚堡油田注水开发过程中，注水压力抬升快、高压欠注的问题，结合冀东低渗透油藏物性特征制得阳离子-非离子表面活性剂降压增注剂JDZC，研究了JDZC加量对其表面张力、油水界面张力、乳化能力的影响及其耐温性和降压增注能力，并在现场进行了推广应用。结果表明，用聚氧乙烯醚类非离子表面活性剂和环氧丙基三季铵盐制得的JDZC降压增注剂耐温可达130℃。随JDZC加量的增加，溶液表面张力降低并逐渐稳定，500 mg/L JDZC溶液的表面张力为28 mN/m；用冀东油田注入水配制的JDZC溶液的临界胶束浓度为1000mg/L。500~5000 mg/L的JDZC与冀东原油的最低界面张力维持在10-2mN/m的数量级。JDZC对原油的乳化能力较好，且加量越大，乳化能力越强。JDZC对冀东高尚堡主力层岩心具有明显的降压增注效果，可使洗油后的岩心渗透率提高40%，压力降低26%。现场38口井应用结果表明，现场实施有效率为94%，注水井初期注水压力平均下降8.5 MPa，有效期超过半年，平均单井增注超过2×103m3，改善了冀东高尚堡低渗透油藏注水难题。图3表5参12

Aiming at the problems of rapid rising of water injection pressure and under-injection during the process of water injection in Gaoshangpu oilfield，a cationic-nonionic surfactant and pressure-lowering and injection-increasing agent JDZC was designed through the physical characteristics of low permeability reservoir in Jidong oilfield. The effects of JDZC dosage on surface tension，oil-water interfacial tension and emulsifying ability，and the temperature resistance，pressure-lowering and injection increasing ability of JDZC were studied. Finally，JDZC was applied in the field. The results showed that the temperature resistance of JDZC made from polyoxyethylene ether nonionic surfactant and rosin-based triquaternary ammonium salt could reach 130℃. With the increase of JDZC dosage，the surface tension of JDZC solution decreased and stabilized gradually. The surface tension of 500 mg/L JDZC solution was 28 mN/m. The critical micelle concentration of JDZC solution prepared with injected water in Jidong oilfield was 1000 mg/L. The minimum interfacial tension between 500—5000 mg/L JDZC solution and Jidong crude oil was maintained in the order of 10-2 mN/m. The emulsifying ability of JDZC to crude oil was good，and the larger the dosage，the stronger the emulsifying ability was. JDZC had obvious effect of reducing pressure and increasing injection for the core of Gaoshangpu main formation. The permeability of core after washing increased by 40% and the pressure decreased by 26%. The field application results of 38 wells showed that the field implementation efficiency was 94%，the initial injection pressure of water injection wells decreased by 8.5 MPa on average，the validity period was more than half a year，and the average enhanced injection of single well was more than 2×103 m3，which improved the water injection problem of Gaoshangpu low permeability reservoir.

10.19346/j.cnki.1000-4092.2019.02.016