多孔介质中天然气水合物降压开采影响因素实验研究

Experimental research on influence factors of natural gas hydrate production by depressurizing in porous media

使用自制的一维天然气水合物开采模拟实验装置,对天然气水合物降压开采进行了物理模拟实验研究,考察了降压幅度、降压速度对开采效果的影响。实验结果表明,降压幅度主要影响最终产出气体的总量,降压幅度越大,累积产气量百分比越大。降压速度越大,产气速率越高,当最终压力相同时,降压速度只影响开采持续时间,最终产气量百分比基本一致;降压速度越慢,当压力降到相同水平时累积产气量百分比越大,特别在降压初期这一现象更明显。

The physical simulation experiments of natural gas hydrate （ NGH ） production by depressurizing in sand-packed porous media were carried out using a new type of apparatus self-designed. Different influence factors were analyzed. Under the experimental conditions, the depressurizing range mainly affects the accumulative gas production, and the higher the de- pressurizing range is, the higher the percent of the accumulative gas production is. And the higher the depressurizing rate is, the higher the gas production rate is. The depressurizing rate just has effect on the continued time of production when the ultimate pressure is certain. The slower the depressurizing rate is, the higher the percent of accumulative gas production is when the ultimate pressure is certain, especially in the initial stages of depressurizing.