盐岩储气库堆积物注气排卤试验研究

Experimental Study on Gas Injection and Brine Ejection of Deposits in Rock Salt Gas Storages

随着国内天然气工业的发展,地下储气库作为集输储运重要的基础设施,其必要性愈加凸显。盐岩储气库是一种重要的地下储气库类型,国内建库盐层由于夹层多、品位低等诸多地质特点,建成后一般在腔内会堆积有大量不溶物。为加强对堆积物空隙体积的认识,明确堆积物空隙注气排卤效果,采用气体膨胀法对其空隙体积进行了试验测定,并基于物理模拟装置开展了堆积物空隙注气排卤试验研究与分析。研究结果表明,堆积物空隙注气排卤后,由于束缚水现象的存在预计有19.83%体积的卤水无法排出而剩余在空隙中;且排卤前空隙初始空间越大,排卤后剩余卤水体积越小,即注入气体所能驱替排出的卤水量越多。

With the development of domestic natural gas industry,the necessity of underground gas storage as the important infrastructure of gas gathering and transportation has become increasingly obvious.Rock salt gas storage is an important type of underground gas storage.For domestic salt formation,there will be lots of deposits in cavity after completion because of the formation’s geological characteristics such as many interlayers and low grade.In order to strengthen the understanding on void volume of deposits,and clarify the effect of injecting gas and ejecting brine(IGEB)in deposit void,the gas expansion method is adopted to test and measure the void volume,and based on physical simulation device study on IGEB in deposit void is carried out.According to the research results,after IGEB of the deposit void,there is 19.83%(volume fraction)of brine remains in void which cannot be ejected because of existence of irreducible water.What's more,the bigger the initial space of void before ejecting brine,the smaller the remaining brine volume after ejecting brine,namely the bigger the brine volume that injected gas can displace.