煤层气垂直井排采控制决策系统的开发

合理的排采工作制度是提高煤层气井产量和节约成本的关键。根据煤层气井压裂裂缝延伸特点和排采过程相态变化特点,结合压力传递模型及Langmuir吸附模型,得出了不同排采阶段的识别标识;根据KGD模型,结合压裂施工工艺参数,以及渗透率与孔隙度的关系,分别建立了水平最小、最大主应力方向上的渗透率预测模型;根据达西定律及排采过程中煤基质与裂隙的正负效应,建立了不同排采阶段物性参数变化模型;根据压力传递特点及气、水相对渗透率变化,最终建立了不同排采阶段、不同过程的排采强度预测模型。借助Visual Basic开发工具,研制了煤层气垂直井排采控制决策系统。晋城矿区潘庄井田应用表明,该系统具有一定的应用前景。

Development of a controlling and decision-making system for coalbed methane drainage vertical wells

Rational working system is the key to enhance gas production and save cost of the coalbed methane wells.According to extension characteristic of the fractured crack in coalbed methane wells,changing characteristic of the phase state during drainage,combined with pressure transferring model,and the Langmuir adsorption model,distinguishing identifiers in the different drainage stages were gained.Based on KGD model,combined with fracturing operating parameter and the relation between permeability and porosity,the permeability prediction models in the direction of minimal and maximal horizontal stress were built.Based on Darcy laws,combined with positive and negative effect of coal reservoir,the changing models of parameters in different drainage stages were built.Based on the pressure transferring characteristic and change of gas and water relative permeability,the drainage intensity models in the different drainage stages in the different processes were built;with the developing tool of VB,a controlling and decision-making system for coalbed methane drainage from vertical wells was developed.Results showed the preferable application prospect.