低渗气井压力恢复资料解释新方法

A NEW METHOD OF BUILD-UP PRESSURE DATA INTERPRETATION FOR LOW PERMEABILITY GAS WELLS

郭康良 周丽娟

Guo Kangliang Zhou Lijuan

低渗气藏早期压力恢复资料由于受相态变化和非达西效应等因素的影响,无法进行可靠的解释。利用Duhamel原理推导出利用早期资料求地层压力的公式,再利用该压力作为匹配控制点,用早期资料在理论图版上进行匹配,从而求出地层参数。用此方法可有效地利用气井压力恢复早期的测试资料,缩短关井时间。由于用地层压力作为统一控制条件,因此,用该方法求得的地层参数可信度高,这一点在实际应用中得到证实。

Early-time pressure build-up data of low permeable gas reservoirs,affected by fluid phase changs and non-Darcy effect,can not be used in pressure data interpretation.In this paper,a new method is developed in which phase change is used as the condition,and Duhamel’s principle is used to derive formation pressure equation and then calculate the formation pressure in low permeability wells with early time data,and use this pressure as a match point to match the early time data,thus getting the formation parameters.It has been proved by practice that the parameters obtained by this method possess high reliability.

10.11743/ogg19980110