计算异常高压气藏地层压缩系数的一种新方法

A new method for calculating the formation compression factor of abnormally high-pressure gas reservoirs

准确的地层压缩系数在开发异常高压气藏的过程中有着重要意义.为了正确获得随气藏开发而不断变化的地层压缩系数,在研究现有方法的基础上,通过分析异常高压气藏地层压缩系数随地层压力动态变化的特点,从天然气体积系数与地层压缩系数定义出发,运用产量递减律和采气指数概念,推导了地层压缩系数动态变化的表达式.将本方法与经验公式法计算的地层压缩系数进行了对比,结果表明,本方法计算的地层压缩系数更合理、准确,并且是一个能够正确反映气藏开发特征的动态值.

It is important to obtain the accurate formation compression factor in the development of the abnormally high-pressure gas reservoirs.In order to gain the correct formation compression factor varying in the development of the gas reservoir,a new expression for formation compression factor was derived from the definitions of natural gas volume coefficient and formation compression factor and by analyzing dynamically varying characteristics of the formation compression factor with the formation pressure.Compared with the formation compression factors calculated by the empiric formulas,the formation compression factor calculated by the new expression is more reasonable and accurate,and it is a variable that can correctly reflect the development performance of the abnormally high-pressure gas reservoirs.