低渗煤层注CO2增抽瓦斯数值模拟与应用  

Simulation and test of enhancement of gas drainage through CO2 injection into coal seam of low permeability

作　　者：白刚[1,2] 周西华[1,2] 魏士平 范超军[4] 李雪明 BAI Gang;ZHOU Xihua;WEI Shiping;FAN Chaojun;LI Xueming(College of Safety Science & Engineering,Liaoning Technical University,Fuxin 123000,China;Key Laboratory of Mine Thermodynamic Disasters & Control of Ministry of Education,Fuxin 123000,China;Changcun Coal Mine,Shanxi Lu'an Environment and Energy Development Co.,Ltd.,Changzhi 046100,China;College of Mining Engineering,Liaoning Technical University,Fuxin 123000,China)

机构地区：[1]辽宁工程技术大学安全科学与工程学院,辽宁阜新123000 [2]矿山热动力灾害与防治教育部重点实验室(辽宁工程技术大学),辽宁阜新123000 [3]山西潞安环保能源开发股份有限公司常村煤矿,山西长治046100 [4]辽宁工程技术大学矿业学院,辽宁阜新123000

出　　处：《煤田地质与勘探》2019年第3期77-84,共8页Coal Geology & Exploration

基　　金：国家自然科学基金项目(51274115);辽宁省教育厅城市研究院重点项目(LJCL001)~~

摘　　要：针对低渗透性煤层瓦斯抽采难度大、抽采效率低等问题,基于CO2-CH4多组分气体竞争吸附作用,开展了注CO2提高煤层瓦斯抽采率数值模拟与试验研究。首先,建立了考虑气水两相流与Klinkenberg效应的煤层注CO2促抽瓦斯流固耦合模型,利用COMSOL软件进行了煤层注CO2后煤层瓦斯压力、瓦斯含量和瓦斯抽采率等参数变化规律,并应用于工程试验。结果表明:构建的气水两相流瓦斯抽采流固耦合数学模型可靠、合理;注入CO2抽采煤层气瓦斯压力、瓦斯含量均比未注入CO2抽采下降速率快;现场试验后,注气抽采条件下瓦斯抽采浓度平均值是未注气条件下的2.02倍,瓦斯抽采纯量是后者的3倍。煤层注入CO2气体后,瓦斯抽采量增加,显著促进了煤层瓦斯抽采。In view of the difficulty of gas extraction and low drainage efficiency in coal seam of low permeability,based on multi component gas competitive adsorption of CO2-CH4,simulation and test for improving seam gas ex-traction rate through CO2 injecting CO2 into coal seam were carried out.A fluid-solid coupling model considering gas-water phases and Klinkenberg effect of CO2 injection into coal seam for enhancement of gas drainage was es-tablished,parameters of gas pressure,gas content and gas extraction rate after coal seam CO2 injection were ana-lyzed by using COMSOL software and applied in engineering test.The results show that mathematical model of fluid-solid coupling is reliable and reasonable.Gas pressure and gas content in CO2-injected coal seam decreased faster than those without CO2 injection.After the field test,the gas concentration increased by 2.02 times and the pure gas extraction volume increased by 3 times.Gas extraction increased after CO2 had been injected in coal seam,which promotes obviously the gas extraction.

关 键 词：低渗透性煤层 煤层注CO2气体 气–水两相流 流–固耦合模型 产气率 

分 类 号：X936[环境科学与工程—安全科学] TD75[矿业工程—矿井通风与安全]