储气库多次气水互驱实验

EXPERIMENTAL STUDY ON MULTIPLE GAS ＆ WATER INTERACTIVE DISPLACEMENTS IN UNDERGROUND GAS STORAGE

枯竭油藏和含水构造改建地下储气库是目前新建储气库的重要趋势之一。为了研究地下储气库在建库以及运行过程中的多相渗流特征，采用物理模拟实验的方法分析了枯竭油藏及含水构造改建储气库多次气水互驱多相渗流气液相渗曲线上的变化规律。研究表明：枯竭油藏及含水构造在气水互驱过程中渗流规律与经典教科书中不一样，气相渗透率渗吸过程比排驱过程的低，而水相渗透率则渗吸比排驱过程的高；枯竭油藏由于有油相的影响，含水构造气相渗透率比含油构造高，分析认为含水构造比含油构造更有利于改建储气库。

Converting depleted oil reservoirs and water-bearing structures into underground gas storages is one of the most important tendencies of building gas storage at present. To capture the multi-phase flow characteristics of underground gas storage during its building and running, physical simulation has been performed to analyze the var- iations of gas-liquid relative permeability curves during gas-water interactive displacement and multi-phase flow, when converting depleted oil reservoirs and water-bearing structures into underground gas storages. Results of the a- nalysis indicate that the flow rules of depleted oil reservoirs and water-bearing structures during gas-water interactive displacement differ from that descried in classic textbooks and gas permeability during imbibition is lower than that during expulsion, on the contrary, the water permeability during imbibition is higher than that during expulsion, besides, due to the existence of oil phase in depleted oil reservoirs, the gas permeability of water-bearing structures is higher than that of oil-bearing structures and compared with oil-bearing structures and after the analysis, the water-bearing structures are considered to be more adequate to be converted into underground gas storage.