煤层气井整体解吸出现时间计算方法

Method to calculate overall desorption appearance time in coalbed methane well

为了判断煤层气井整体解吸出现时间,基于油气藏数值模拟软件,以沁水盆地A区块典型井为原型,建立煤层气理想数值模型,分析了整体解吸出现时间与渗透率、孔隙度、煤层厚度、临界解吸压力等的关系,结果表明:整体解吸出现时的地层水采出程度与孔隙度、临界解吸压力相关,而与渗透率、煤层厚度无关。并首次形成了出现整体解吸时地层水采出程度与煤层物性的关系图版,通过该图版,研究人员可快速判断煤层气井是否实现整体解吸,对煤层气的高效开发具有一定的指导作用。

In order to judge the overall desorption appearance time in the coalbed methane well,based on the numerical simulation software of the oil and gas reservoir,taking the typical well A Block in Qinshui Basin as the original type,an ideal numerical model of the coalbed methane was established and was applied to analyze the relationship of the overall desorption appearance time to the permeability, porosity,seam thickness,critical desorption pressure and others.The results showed that when the overall desorption was appeared,the water yield degree from the strata was related to the porosity and the critical desorption pressure,but was not related to the permeability and seam thickness.When the overall desorption was appeared,the relation board between the strata water yield degree and seam properties was firstly formed.With the relation board,the researchers could rapidly judge the coalbed methane well whether realize the overall desorption or not and the relation board could have certain guide function to the high efficient development of the coalbed methane.