边底水活跃油藏常采用大剂量多段塞调堵或打人工隔板抑制底水上升.为解决传统工艺堵剂用量大、成本高的问题,研制在地层可自发膨胀的自生气泡沫冻胶体系,以成胶强度、成胶时间、成胶体积为评价指标,通过正交实验优选最优体系,分析自生气可膨胀泡沫冻胶性能的影响因素.结果表明:自生气泡沫冻胶体系具有体膨倍数高、封堵性能好的优点,可以实现边底水水侵治理、封堵封窜的目的;在温度为60℃、pH值为6.5~7.4时体系性能最佳,此时成胶时间28 h,成胶强度G级,体膨倍数超过300%;注入的泡沫冻胶对岩心大孔隙进行了有效封堵,减少了岩心的非均质性差异,泡沫冻胶具有显著的体膨调堵性能;可通过调节pH值实现对自生气可膨胀泡沫冻胶性能的调控,以满足不同储层堵剂的差异性放置需求.%Large-dose and multi-slug plugging method or filling artificial barrier have been widely used to control water coning in active edge and bottom water reservoirs, which will cause the large consumption of plugging agent and high cost. In order to solve this problem, the authigenic gas foam gel plugging system was developed. By means of orthogonal experiments, the optimal formula was selected using gel strength, gel time, and gel volume as evaluation indexes and the influencing factors were analyzed as well. The results show that the authigenic gas foam gel plugging system has the advantages of high volume expansion and outstanding plugging performance, which can achieve the purpose of controlling water invasion, sealing and channeling. The performance of this system is optimum at the temperature of 60 ℃ and pH of 6. 5-7. 4. The gel time is 28 hours while the gel strength is G grade, whose volume expansion is more than 300%. The injected foam gel is able to allevi-ate the core heterogeneity difference by plugging the large holes in core. And the characteristic of the authigenic foam gel can be regulated by changing the value of pH to meet the requirements of placing different plugging agents on different locations.
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