高温海水基压裂液研究及应用

通过室内实验研究,得到了适合海上高温深井压裂的高温海水基压裂液,其耐温达160℃,可以用矿化度40 000mg/L以内的过滤海水直接配制;合成了含有羟丙基和磺酸基的耐盐稠化剂PA-SRT,并通过核磁共振方法进行了表征。通过使用溶解促进剂使耐盐稠化剂5 min内黏度可达到最终黏度的80%,满足连续混配装置和增产作业船的使用要求。在国内某油田153℃油井压裂施工中成功应用,压裂液采用过滤海水直接配制,用液量565.2 m~3,加入支撑剂39.69 m~3,支撑剂质量浓度最高为491 kg/m~3。说明该高温海水基压裂液综合性能达到了现场应用的要求。

Research and application of high temperature seawater-based fracturing fluid

Based on the laboratory experiments,a high temperature seawater-based fracturing fluid for fracturing of high temperature and deep wells was studied.The fracturing fluid is resistant to temperature up to 160 ℃,and could be directly formulated with the filtered seawater with the mineralization of 40 000 mg/L.The salt resistant thickener called PA-SRT,which contains hydroxypropyl and sulfonic acid group,was synthesized and characterized by nuclear magnetic resonance method.The viscosity of the salt resistant thickener can reach 80％ of the final viscosity within 5 minutes by using a dissolution promoter,meeting the demand of continuous mixing device and well stimulation support vessel.The seawater-based fracturing fluid was applied successfully to a well of 153 ℃ in a domestic oilfield during fracturing construction.The fracturing fluid was prepared by filtered seawater directly,and 39.69 m3 proppant had been pushed into the formation with 565.2 m3 fracturing fluid,while the highest proppant concentration was 491 kg/m3.The result shows that the comprehensive performance of the high temperature seawater-based fracturing fluid meets the requirement of field application.