盐岩储气库注气排卤工艺参数的数值模拟

Numerical simulation on technological parameters of gas injection and brine discharge in salt-cavern gas storage

盐岩储气库注气排卤后期,由于气水界面锥进形成气窜使得腔底大量卤水无法全部排出,从而导致腔体利用率无法最大化。为尽可能多地将卤水排出以实现腔体库容优质建设,以金坛库区A井为例,基于其声呐测腔数据,利用数值模拟软件建立腔体地质模型,进而模拟不同注气压力和注气量条件下注气排卤生产情况,并进行了相应的排卤效果对比分析,结果表明:注气压力或注气量越大,产生气窜现象时间越早,最终累积排出卤水也越少;随着注气参数的提高,日均排卤量增大,但增长幅度变小,并逐渐趋于平稳。

At the later stage of gas injection and brine discharge in salt-cavern gas storage, lots of brine at the bottom of the cavity cannot be discharged for gas channeling is generated due to the coning of gas-water interface, and consequently the utilization rate of cavity cannot be maximized. In order to eject brine as much as possible to achieve the goal of highquality storage building, the cavity geology model was established with Well A in Jintan gas storage as example. The model was based on the sonar cavity test data using numerical simulation software. Then, the gas injection and brine discharge situations under different gas injection pressures and rates were simulated. Finally, the brine discharge effects were compared and analyzed. It is indicated that the greater the injection pressure or injection rate is, the earlier the gas channeling arise and the less the ultimate cumulative brine discharge is. And with the increase of gas injection parameters, the daily average brine discharge increases, but its increasing amplitude declines gradually to the stable value.