单相煤层气井底瞬时压力

The Instantaneous Pressure on Well Bottom with Single-Phase Coal-Bed Methane Adsorption

瞬时压力分析是煤层气勘探与开发过程中获得煤层参数及井筒参数的重要手段,是对煤层气井生产能力的一种测试试验。为了给煤层气勘探和开发提供理论依据,必须对煤层气井井底瞬时压力进行分析。根据煤层气的地质特征及煤层气的产出机理,以多孔介质定常渗流理论为基础,按垂直井、无限大煤层考虑,在一定的假设条件下,建立了平衡吸附单相煤层气的数学物理模型,研究了平衡吸附单相煤层气井底压力与煤层之间的关系,给出了煤层气井底瞬时压力分析方法和步骤,从而可获得有关煤层气参数和井筒参数,为煤层气的开发提供科学依据。

The instantaneous pressure analysis is a means of getting some data in mining coal-bed methane. It is a test for the production capacity of coal-bed methane well. In order to provide scientific basis for mining coal-bed methane, it is necessary to analyze the pressure on well bottom. Based on the characteristics of geology, adsorption and generation mechanism of coal-bed methane, and the steady liquid flow theory of porous media, and considering the vertical well and infinitely great coal bed, a mathematical model of a single-phase coal-bed methane with balanced adsorption has been set up for the first time. The relationship between the solutions to the pressure on the well bottom of single-phase coal-bed methane and the parameters of the coal-bed is studied. The methods to analyze the pressure on well bottom have been researched, and then a scientific basis for mining coal-bed methane is provided.