摘要
有水气藏在改建为地下储气库的过程中,如何合理确定其运行下限压力,最大限度地减少水侵对地下储气库运行的影响,是决定该类气藏建库成败的关键因素之一。目前国内对此主要采用气藏工程方法,该方法主要反映了地下储气库在采气末期受水侵影响较小条件下的运行情况,无法真实反映采气末期水侵对地下储气库运行的影响。为此,运用数值模拟方法,依据产水量、气水比、气水界面和含气饱和度等指标的变化,来表征不同下限压力下水侵对地下储气库运行的影响。研究结果表明:①不同下限压力下,产水量和气水比变化曲线存在1个明显拐点,当下限压力低于该拐点时,产水量急剧上升,气水比急剧下降;②应综合考虑水侵量、地下储气库工作气量规模和工作井数来确定有水气藏改建地下储气库的下限压力;③相对气藏工程方法而言,数值模拟方法更能真实地反映水侵对地下储气库运行的影响。
One of the key factors determining the success or failure of the project of converting a water-bearing gas reservoir into an underground gas storage (UGS) is how to determine its operating lower limit pressure and eliminate the negative effect of water influx on the UGS operation to the maximum degree. At present, the commonly used gas reservoir engineering method in China can only reflect how the converted UGS is going in the final period of gas recovery under little effect of water influx. In view of this, based on the variation of such indexes as water yield, gas-water ratio, gas-water interface, gas saturation, etc. , the numerical simu lation was used to present the impact of water influx under different lower limits of pressure on the operation of UGS. The following results were obtained. (1) Under different lower limits of pressure, there exists an obvious inflection point in the curves of water yield and gas water influx; when the lower limit pressure is under the inflection point, there is a surge in the water yield but sharp drop in the gas-water ratio. (2) The lower limit pressure for this project should be determined through an overall consideration of water yield, working gas capacity of UGS, and working well numbers. (3) Compared with the gas reservoir engineering method, the numerical simulation can reflect more truly the effect of water influx on the UGS operation.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2013年第4期100-103,共4页
Natural Gas Industry
关键词
有水气藏
地下储气库
下限压力
水侵量
数值模拟
产水量
气水比
气水界面
含气饱和度
gas-bearing gas reservoir
underground gas storage
lower limit pressure
water influx
numerical simulation
wateryield
water-gas ratio
gas-water interface
gas saturation