栲胶复合氮气泡沫体系调堵剂性能评价及应用

针对常规氮气泡沫稳泡性能差、对地层水的调堵强度低等缺点,添加栲胶与其复配,得到栲胶复合氮气泡沫体系。室内从成胶性能、起泡性能、耐温耐盐性能、配伍性及封堵性能等6个方面对栲胶复合氮气泡沫体系进行了性能评价。实验结果表明：加入栲胶对氮气泡沫体系的起泡体积基本无影响,但是增强了体系的稳泡性能,提高了体系的残余阻力因子,增强了封堵强度。该体系的耐盐性较强,可应用于高矿化度地层,与目前常用的高温起泡剂具有良好的配伍性,对高温地层的封堵效果较好。应用栲胶复合氮气泡沫体系对4口高含水井及2口汽窜井分别进行了调堵和封窜施工,结果表明该体系对调剖降水和封堵汽窜均有较好效果。

Performance evaluation and application of tannin extract and compound nitrogen foam system plugging agent

Aiming at the shortages such as the poor foam performance of conventional nitrogen foam and the low profile control and plugging intensity for formation water,the tannin extract and nitrogen foam are added to obtain the extract tannin and foam compound system in order to improve the quality of foam.This paper conducts the lab test for performance evaluation on tannin extract foam system from the gelling property,foaming property,heat resistance and salt tolerance performance,compatibility and plugging performance.The results show that the adding of tannin extract has no effect on nitrogen foam volume basically,but greatly enhance the foam stability of the tannin extract foam system.The tannin extract foam system can improve the residual resistance factor and enhance the sealing strength.The system has strong salt tolerance and can be used in the formation with high salinity.In addition,the tannin extract has good compatibility with the current commonly used high-temperature foaming agent and has good effect for plugging the high-temperature formation.The construction of profile control and plugging the steam channeling is conducted in four high water-cut wells and two steam channeling wells,which shows that the system has a good effect in profile control and plugging the steam channeling.