川西中浅层低渗透致密砂岩气藏储层物性差,含水饱和度高,气井产能较低,普遍存在水锁伤害,严重影响了采气中后期气井的正常生产.以室内实验为手段,研究了水锁伤害程度,定量分析了解水锁剂对天然气渗流的改善作用.研究结果表明,低渗透致密砂岩气井采气中后期近井储层积液会引起严重的水锁伤害,影响了天然气在储层中的渗流能力,解水锁剂可降低近井储层的含水饱和度,改善岩心渗透率,降低储层中天然气启动压差.解水锁剂HY在A井现场试验后,该井在油压和套压变化不大的情况下,5个月累积增产气量为24×104 m3,单井增加经济效益为19×104元.%There is serious damage of water block in the low permeability gas reservoir in west Sichuan, and it will cause fluctuation of the normal production. This paper studies the rock near the wellbore in terms of wettability and liquid interfacial tension between the two phases, as well as the performance of water unlocking agents on the natural gas percolation. The results show that the accumulated liquid in the near wellbore zone may cause serious damage on the flow of natural gas capacity because of watei lock. The unlocking technology of water-lock agent can reduce the near-wellbore water saturation and improve the core permeability, so as to lower the start up pressure of natural gas. According to the pilot of well Longsui 19D-3, the well casing pressure is constant on average, meanwhile, the average oil rises by 0.4 Mpa, the average gas production increases by 0.15×04 m3/d, and the cumulative gas increment in 5 months is 24×104m3/d with anticipated economic benefit of 19×104 Yuan. Therefore, the application performance is obvious.
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