废弃油藏建储气库库容变化机理室内实验研究*

地下储气库作为应急气源在调峰中起到重要作用;但目前关于废弃油藏建储气库的基本理论和库容参数预测方面的研究相对较少。采用实际废弃油藏岩心,通过设计与建库过程相似的室内驱替实验,进行了初次注入及后续多次注采转换过程的实验;探索了库容与压力、库容与注采轮次之间的内在关系。结果表明:经过3个轮次注采储气库含气饱和度只能达到40%左右,而后的注采增容能力减弱,5个轮次后趋于达容,含气饱和度达到50%左右。说明废弃油藏由于含水和含油的影响,库容最大仅能达到废弃油藏整个储集空间的一半,解决了以往计算库容不准确的问题。

A Research on the Change Mechanism of Storage Capacity of Abandoned Oil Reservoirs to Build Gas Storage Space through Indoor Test

Underground gas storage used as an emergency air supply plays an important role in the peak shaving, but at the moment the basic theories and storage capacity parameter prediction about abandoned oil reservoir building gas storage is relatively little. Based on the actual abandoned reservoir cores, through the design and building process similar to that of interior displacement experiment, carring on the initial injection and subsequent multiple injection-production conversion process of experiment, exploring the internal relationship between the storage and the pressure,and the relationship between capacity and injection-production rounds.The results show that after three rounds injection-production, gas saturation of gas storage can only achieve about 40%, then the injection-production capacity expansion ability abates, and the storage capacity will attain its maximum after five rounds, gas saturation achieve about 50%. Due to the influence of water and oil, the largest storage capacity can only achieve half of the abandoned reservoir space, solving the problem of calculating the storage capacity.