Physical simulation of the mechanism for operation of water-encroached (flooded) underground gas storage facilities

Abstract

We have developed a physical simulation model for gas injection/withdrawal consistent with the characteristics of water-encroached (flooded) underground storage facilities and we have simulated the construction and operation of the storage facility. Based on the operating schedule for the flooded underground gas storage and the mechanism for gas and water percolation in the flooded reservoir, we determined the important characteristics of flooded storage facilities including porosity, degree of flooding, and degree of heterogeneity of the reservoir as well as the operating scheme. We found that the degree of flooding and the heterogeneity of the reservoir are the crucial parameters for flooded storage facilities. We show that homogeneous reservoirs should be used as the main target layer of an underground gas storage facility. The water content in the reservoir must be taken into account during injection and withdrawal of gas from the storage facility.