低渗透砂岩气藏水锁伤害方式对比实验研究

Experiment research on water locking damage in low-permeability sand gas reservoirs

通过室内实验研究,对低渗透砂岩气藏3种不同的水锁伤害方式进行了对比研究。研究表明,低渗透砂岩气藏的水锁伤害具有普遍性和严重性,其中欠压作用下的水锁伤害最小,超压作用下的水锁伤害最大,常压作用下的水锁伤害居中。因此,在低渗透砂岩气藏的开采过程中应尽量避免使用水基工作液,如果要用水基工作液,应使压差处于欠压状态。

Based on the lab experimental research, the comparison is performed among the three types of water locking damage of low-permeability sand gas reservoirs. The research shows that water locking damage happens widely and seriously in low-permeability sand gas reservoirs. Among these three types of water locking damage, the water hocking under underpressure condition has the minimal damage, the damage under overpressure condition is relatively maximal, and the damage under normal pressure is relatively medial. We should not use water base working fluid, if have to, we should make it in the underpressure condition.