Study on Performance Evaluation of Profile Control System with High Temperature Resistant Weak Gel Prepared from the Produced Fluid

The use of highly mineralized reinjection water has low gel strength and poor stability, and the above problems are more prominent under high-temperature reservoir conditions. Based on the temperature resistance and salt tolerance polymer TSRP and phenolic resin crosslinking agent, a TSRP temperature resistant weak gel system suitable for high mineralized reinjection water was developed, and the temperature resistance mechanism of the TSRP weak gel system was tested by its temperature resistance and injection ability. The migration, retention, and plugging of the TSRP weak gel system in heterogeneous reservoirs were studied through micropore throat migration and plugging characteristics and dual-pipe parallel oil displacement experiments. The results showed that: under the condition of polymer concentration 2000 mg/L, polymer: crosslinking agent: glue promoter 1:1.5:1, the TSRP weak gel system prepared by using mineralized 12132.9 mg/L reinjection water can remain stable after 95°C aging at high temperature of TSRP. Through microscopic simulation, a glass etching model TSRP weak gel system showed good migration ability and plugging performance. In comparison with the two pipes parallel oil displacement experiment, the KY gel system injected the same amount of PV at 95°C and 20000 mg/L in the Y1L block, the average recovery of the TSRP gel system increased by 22.3% after injection of polymer gel, and the KY gel system was only 18.2%; When the same amount of PV was injected in Z1L block, 95°C and 22000 mg/L, the average recovery of TSRP gel system increased by 24.35% after injection of polymer gel, and the KY gel system was only 17.15%, that is, under higher salinity, the TSRP gel system showed better performance.