深浅煤层同压合采煤层气的适用性分析及工艺  

Applicability analysis and technique of combined coalbed methane drainage at same pressure in deep and shallow depth seam

作　　者：张健[1] ZHANG Jian(China United Coalbed Methane Corporation Limited,Beijing 100015,China)

机构地区：[1]中联煤层气有限责任公司,北京100015

出　　处：《煤炭科学技术》2018年第6期101-106,共6页Coal Science and Technology

基　　金：国家科技重大专项资助项目(2016ZX05066)

摘　　要：针对深浅煤层合采煤层气的过程常受到井筒内压力影响,导致合采井产量达不到预期产值,甚至低于单层产量的问题,通过分析深浅部煤层特征,将合采作业在井筒中的状态分为浅部煤层、深部煤层、深浅部煤层同时进入气水两相流状态3种情况,并分析每种情况下的合采可能性,建立相关井筒内的压力模型,以兼容参数允许压力差值Δp为基础提出调压合采,通过示例井进行计算,Δp值分别在0.4、0.6、0.8、1.0 MPa逐渐增大时,合采井的产气量逐步提升,最终确定Δp为1.0 MPa时,可以达到最佳兼容状态。研究结果表明调压合采工艺可适用于多煤层的合采作业。According to the influences from the well hole internal pressure during the joint coalbed methane drainage process of the deep and shallow seams,the production of the joint drainage wells could not reach the pre-scheduled production and even lower than a single seam production. With the analysis on the deep and shallow seam features,the joint drainage operation status in the well hole could be divided into three conditions： shallow coal seam,deep coal seam and both of them taking state of two-phase flow. The joint drainage feasibility under each condition was analyzed. A pressure model within the well hole was established. Based on the compatible data allowed the pressure difference Δp as the basis,the commingled production technique was conducted with the pressure adjustment in the well hole.With the calculation conducted on the demo wells,when Δp value was 0.4,0.6,0.8 and 1.0 MPa individually,the commingled production increased as Δp raise up and the most fix state was maken under Δp was 1.0 MPa. The data results showed that the commingled production technique with the pressure adjustment could be suitably applied to the joint drainage operation in the multi seams.

关 键 词：深、浅煤层 同压合采 煤层气 压降差值 

分 类 号：TD712[矿业工程—矿井通风与安全] P618[天文地球—矿床学]