官寨井田多煤层开发产层组合研究

Study on Multiple Coal Seams Exploitation Layers Combination in Guanzhai Minefield

官寨井田煤层群普遍发育,合层排采可以降低开发成本、提高单井产量,是多煤层区块煤层气开发的必然趋势。不同的产层组合方式,因各项物性参数存在差异,从而使产能差异较大。结合官寨井田的地质条件以及X井的排采数据,利用CBM-SIM数值模拟手段,对不同产层组合方式进行深入研究。结果表明:官寨井田影响合采的主要因素为:渗透率比值、临界解吸压力差和储层压力差。通过对比分析不同组合的产能曲线得出,煤组1、3为官寨井田适合合层排采的组合,其他组合因各主要影响因素存在差异,造成各煤层之间的层间干扰较大,因而不适合合层排采,研究结果将对类似地区的合层排采提供一定的指导。

Coal groups in the Guanzhai minefield have generally developed, the CBM commingled drainage can lower down exploitation cost, improve single well output, thus the inevitable trend of CBM exploitation in multiple coal seams block. To different exploitation layers combinations because of different physical properties can cause larger capacity difference. Combined with geological condition in Guanzhai minefield and well X drainage data, through CBM -SIM numerical simulation studied different exploitation layers combina- tions in detail. The result has shown that main factors impact exploitation layers combination in the minefield have permeability ratio, critical desorption pressure differential and reservoir pressure differential. Through comparative study of different combination capacity curves has shown that the coal group Nos. 1 and 3 are the layers combination suitable to CBM drainage in the minefield. Other combina- tions because of main impacting factor differences can cause larger interlayer interference between coal seams, thus not suitable to lay- ers combination drainage. The study will provide certain guidance in similar area layers combination CBM drainage.