基于产能分析的多煤层气藏产层组合选择  

Selection of the production layer combination for multi-coal seams based on productivity analysis

作　　者：郭肖 毛军 邸德家[1,2] 杜娟 张同义[1,2] GUO Xiao;MAO Jun;DI Dejia;DU Juan;ZHANG Tongyi(State Key Laboratory of Shale Oil and Gas Enriching Mechanisms and Effective Development,Beijing 100101,China;SINOPEC Research Institute of Petroleum Engineering,Beijing 100101,China)

机构地区：[1]页岩油气富集机理与有效开发国家重点实验室,北京100101 [2]中国石化石油工程技术研究院,北京100101

出　　处：《大庆石油地质与开发》2022年第2期157-166,共10页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家科技重大专项“多煤层合采全过程流动机理及产能预测研究”(2016ZX05044005-001)。

摘　　要：针对多煤层气储层中的多尺度、多区域、多介质复杂流动问题,基于煤层双孔—单渗模型和层间窜流模型,考虑了产气阶段井筒气—水两相管流对井底流压的影响,建立了多煤层气藏全过程气—水两相耦合流动模型,采用数值方法对耦合模型进行求解。从产能角度对影响多煤层气合采井产能的因素进行敏感性分析,并基于产能贡献率分析对多煤层气藏进行层系划分,将空间上相邻、储层物性相近的煤层划分为一个产层组合,建立了多煤层气藏层系划分流程和判定准则,可以划分为一个层系的煤层渗透率级差不应超过4,初始含气饱和度级差不应超过100,Langmuir体积级差不应超过5。滇东地区煤层气井LC-C4井产气曲线的拟合和预测结果也初步证实了该方法的可靠性。Aiming at the problems of multi-scale,multi-region and multi-media complex flow in multi-coal seams and based on the dual-porosity single-permeability model of the coal seams and the interlayer crossflow model,the whole-process gas-water two-phase coupled flow model of the multi-coal seams is established by considering the effect of gas-water two-phase pipe flow on the well bottom flow pressure during the gas production,and the coupled model is solved by the numerical methods.The sensitivity analysis of the factors affecting the commingled production of the multi-coal seams is carried out from the perspective of the productivity,and the series of the multi-coal seams are classified according to the analysis of productivity contribution rate.Adjacent coal seams with similar properties are selected as production layer combination and then the process and judgment criteria for the classification are established.The permeability difference of coal bed in the same series should not exceed 4,the initial gas saturation difference should not exceed 100,and the Langmuir volume difference should not exceed 5.The matching and prediction of the gas production curves for CBM Well LC-C4 in Diandong area also confirm the reliability of this method preliminarily.

关 键 词：多煤层 井筒气—水两相管流 层间窜流 产层组合 

分 类 号：TD712[矿业工程—矿井通风与安全]