基于排采数据的煤层气井排水-降压-产气有效性研究——以黔西织金区块为例  

Effectiveness of drainage,depressurization and gas production of coalbed methane wells based on production data:A case study of the Zhijin Block in Western Guizhou

作　　者：郭晨[1,2,3] 史康 秦勇 袁航[5] 陈贞龙 高为 卢玲玲 李猴强 张旭阳 王祥 何红斌 张润涵 GUO Chen;SHI Kang;QIN Yong;YUAN Hang;CHEN Zhenlong;GAO Wei;LU Lingling;LI Houqiang;ZHANG Xuyang;WANG Xiang;HE Hongbin;ZHANG Runhan(College of Geology and Environment,Xi’an University of Science and Technology,Xi’an 710054,China;Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation,Xi’an 710054,China;Geological Research Institute for Coal Green Mining,Xi’an University of Science and Technology,Xi’an 710054,China;Key Laboratory of CBM Resources and Reservoir Formation Process,Ministry of Education,China University of Mining and Technology,Xuzhou 221116,China;Sinopec East China Oil&Gas Company,Nanjing 210011,China;Guizhou Provincial Engineering and Technology Research Center of Coalbed Methane and Shale Gas,Guiyang 550008,China;Department of Geology,Northwest University,Xi’an 710069,China;Aerophoto Grammetry and Remote Sensing Bureau,China National Administration of Coal Geology,Xi’an 710199,China)

机构地区：[1]西安科技大学地质与环境学院,陕西西安710054 [2]陕西省煤炭绿色开发地质保障重点实验室,陕西西安710054 [3]西安科技大学煤炭绿色开采地质研究院,陕西西安710054 [4]中国矿业大学煤层气资源与成藏过程教育部重点实验室,江苏徐州221116 [5]中国石油化工股份有限公司华东油气分公司,江苏南京210011 [6]贵州省煤层气页岩气工程技术研究中心,贵州贵阳550008 [7]西北大学地质学系,陕西西安710069 [8]中国煤炭地质总局航测遥感局,陕西西安710199

出　　处：《煤炭科学技术》2025年第3期370-384,共15页Coal Science and Technology

基　　金：国家自然科学基金资助项目(42472243,42002195);国家自然科学基金重点资助项目(42130802)。

摘　　要：煤层气井排水、降压、产气是一个递进过程,可分解为排水降压与降压解吸产气2个环节,任一环节失效均会导致产气受限。通过分析排采数据剥离上述2个环节的有效性,明确解吸产气的主要制约因素,对于促进煤层气经济有效开发具有重要意义。构建了一种基于累计产水量与井底流压、累计产气量与井底流压、以及累计产水量与累计产气量3条关系曲线的排采有效性分析方法,具有水侵识别、水源劈分、气藏参数获取与关键环节剥离等功能,将其应用于黔西织金区块煤层气井排采动态分析,取得一定成效。基于累计产水量与井底流压关系曲线,上凹型代表水侵井,下凹型代表非水侵井。面向开发需求,将含气系统概念延伸为产气系统,指具有相近水文地质条件、开发动态及生产规律的含气系统及其组合,不同产气系统合采兼容性差。织金区块含煤地层可划分为上部(1~9号煤层)与下部(10~35号煤层)2套产气系统,上部产气系统水文地质开启程度高,易发生水侵,而下部产气系统水文地质条件较为封闭,无明显水侵现象,有利于高效降压与产气。气藏属性参数计算结果显示,水侵井具有启抽压力低,弹性产水指数高的特点,非水侵井与之相反。水侵井的水侵产水量大于弹性产水量,总产水量高;非水侵井主要产出弹性水,总产水量低。产水能量驱动类型的差异决定了排水降压有效性,进而影响了气井的产能潜力。限制或避免水侵、提高排水降压有效性将是织金区块老井提产改造与新井开发设计的基本思路。研究成果可为叠置煤层气系统发育背景下的煤层气井排采动态分析与产能主控因素诊断提供方法借鉴。The process of drainage,depressurization,and gas production in coalbed methane wells is a progressive process that can be decomposed into two steps:the effectiveness of drainage inducing depressurization,and the effectiveness of depressurization inducing gas production.Failure in either step can lead to limited gas production.Discriminating the effectiveness of the two steps based on the analysis of production data and identifying the main constraints on gas production are of great significance for promoting the economic and efficient development of CBM.An analysis method was constructed for the effectiveness of CBM recovery based on three relationship curves:cumulative water production and bottom-hole flow pressure,cumulative gas production and bottom-hole flow pressure,and cumulative water production and cumulative gas production.It has the functions of water invasion identification,water source splitting,gas reservoir parameter acquisition,and key production step distinction.It has been applied to the dynamic analysis of CBM production in the Zhijin block in western Guizhou,and has achieved certain results.Based on the relationship curve between cumulative water production and bottom-hole flow pressure,the up-concave type represents water-invaded wells,while the down-concave type represents non-water-invaded wells.Facing the development demand,the concept of gas-bearing system is extended to gas-producing system,which refers to gas-bearing system and their combinations with similar hydrogeological conditions,development dynamics,and production rules.The compatibility of different gas-producing systems is poor.The coal-bearing strata in the Zhijin block can be divided into two gas-producing systems:the upper system(Coal Seams 1-9)and the lower system(Coal Seams 10-35).The upper system has a high degree of hydrogeological opening and is prone to water intrusion,while the lower system has relatively closed hydrogeological conditions and no significant water intrusion,which is conducive to efficient pressure reduc

关 键 词：煤层气排采 水侵识别 产气系统 合采 储层流体效应 动态分析 

分 类 号：TE122[石油与天然气工程—油气勘探]