有限封闭水体气藏动储量计算新方法

A new method to calculate dynamic OGIP of gas reservoirs with restricted and closed aquifers

目前常见的水驱气藏动储量和水体倍数计算方法较为复杂、不易推广,本文在有限封闭水体气藏压降方程的基础上进行了Roach和二项式类似形式简化,提出了计算动储量和水体倍数的简化方法:改进的Roach法和改进的二项式法。利用新方法计算了南海北部A气田的动储量和水体倍数,计算结果与视储量Havlena-Odeh法结果基本一致,证实了方法的可靠性。新方法仅需要p/Z和累产数据进行直接回归计算,不需要对水体形态、水体大小、水层渗透率等不确定参数进行猜测试算,且计算简便,不需要复杂的数据叠加处理计算,因而具有较好的实用性,利于矿场应用与推广。

In view of the prevailing calculation method for dynamic OGIP and aquifer volumes of water drive gas reservoirs being complex and hard to promote,a simplified method for the calculation of dynamic OGIP and aquifer volumes has been put forward by means of the simplification of Roach and binomial-type equations,that is the improved Roach method and improved binomial method.Further,the new method was applied to calculating the dynamic OGIP and aquifer volumes of the A gas field in northern South China Sea,with the calculation results basically coincident with that of the Havlena-Odeh method,thus being proved reliable.The new method,which requires only data of p/Zand accumulative production for direct regression and avoids both tests of indefinite parameters like the aquifer shape,size and permeability and sophisticated data overlay processing,is considered of excellent practicability and in favor of field application and promotion.