利用CO_2作为地下储气库垫底气的理论探讨  

THEORETICAL DISCUSSION OF CARBON DIOXIDE AS CUSHION GAS FOR UNDERGROUND GAS STORAGE TANK

作　　者：李国韬[1] 宋桂华[1] 张军[1] 温庆和[1] 张强[1] 

机构地区：[1]中国石油大港油田集团公司钻采工艺研究院

出　　处：《天然气勘探与开发》2008年第2期61-63,68,共4页Natural Gas Exploration and Development

摘　　要：储气库的作用是保证天然气的平稳供应满足高峰用气的需要。在储气库的运行过程中,天然气随用气量的变化情况被周期性的采出和注入,而用于维持储层下限压力的垫底气是不能被采出的,常用的垫底气是地层剩余的天然气。所作的数值模拟研究表明:用CO2作垫底气是一个很好的选择。因为在接近临界压力时,CO2具有很高的压缩性,密度变化很大。从长远观点看,把CO2废气注入地下,符合环保需要的要求。用CO2作储气库的垫底气是一个发展趋势,但还存在一些需要攻关研究的问题。The underground gas storage tank is to guarantee the stable supplement of natural gas and to meet the peak demand of gas use. During the operation of storage tank, gas is periodically produced and injected along with the change of gas use whereas cushion gas, which may maintain the lower limit of reservoir pressure, is not able to be produced. The common-used cushion gas is the remaining gas from formation. The research on numerical simulation shows that to take carbon dioxide (CO2) as cushion gas is the best choice because it is featured by high compressibility and its density variation is very tremendous when approaching a critical pressure. Taking CO2 as exhaust gas to inject into underground may meet the demand of environmental protection in the future. Taking CO2 as cushion gas for storage tank is a developing trend. However, some existing problems should be further studied.

关 键 词：地下储气库 CO2 垫底气 

分 类 号：TE972[石油与天然气工程—石油机械设备]