结合孔隙结构分析热蒸汽对煤体瓦斯解吸的影响  

Analysis on the Influence of Hot Steam on Coal Gas Desorption Combined with Pore Structure

作　　者：王杰 赵东 蔡婷婷[1,2] 李磊 WANG Jie;ZHAO Dong;CAI Tingting;LI Lei(School of Safety and Emergency Management Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;Key Laboratory of In-situ Property Improving of Ministry of Education,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China)

机构地区：[1]太原理工大学安全与应急管理工程学院,山西太原030024 [2]太原理工大学原位改性采矿教育部重点实验室,山西太原030024

出　　处：《矿业研究与开发》2021年第5期113-117,共5页Mining Research and Development

基　　金：国家自然科学基金项目(51904197);山西省自然科学基金项目(201801D121283).

摘　　要：为了探究热蒸汽对煤体瓦斯解吸能力的影响,以阳泉新元煤矿贫煤为研究对象,采用压汞法分析了热蒸汽处理前后煤体的孔隙结构演化,结合吸附—解吸试验,用解吸率和解吸时间临界值表征热蒸汽和水分对煤体瓦斯解吸的影响。结果表明:(1)热蒸汽处理后煤体的总孔容、滞后环面积、孔隙率、渗透率及平均孔径均有增大,煤体小孔向大孔发育,闭合孔隙向开放孔隙转变,孔隙结构的连通性明显提升;(2)煤体瓦斯解吸率随着平衡压力增大而增大;热蒸汽的使用有效促进煤体残余吸附瓦斯的解吸,消除了煤体中水分抑制瓦斯解吸的影响,瓦斯解吸率明显增大;(3)热蒸汽作用下煤体瓦斯解吸时间效应临界值明显降低,解吸达到平衡所需的时间缩短,解吸效率显著提升。该研究为煤层注热强化煤层气开采提供了一定的理论依据。In order to explore the influence of hot steam on the gas desorption capacity of coal body,taking the lean coal of Yangquan Xinyuan Coal Mine as the research object,the mercury intrusion method was used to analyze the pore structure evolution of coal body before and after the hot steam treatment.Combined with the adsorption-desorption experiment,the critical values of the desorption rate and desorption time were used to characterize the effects of hot steam and moisture on coal gas desorption.The results are concluded as follows.Firstly,after hot steam treatment,the total pore volume,hysteresis ring area,porosity,permeability and average pore diameter of the coal body increases.Small pores develop to large pores and closed pores transform to open pores,so the connectivity of pore structure is significantly improved.Secondly,the coal gas desorption rate increases with the increase of equilibrium pressure.The use of hot steam effectively promotes the desorption of residual adsorbed gas in the coal,and eliminates the influence of moisture in the coal to inhibit gas desorption,so as to significantly increase the gas desorption rate.Thirdly,the critical value of the time effect of coal gas desorption under the action of hot steam is significantly reduced,the time required for desorption to reach equilibrium is shortened,and the desorption efficiency is significantly improved.The research provides a certain theoretical basis for coal seam heat injection to strengthen the exploitation of coalbed methane mining.

关 键 词：热蒸汽 孔隙结构 压汞 注水 瓦斯解吸 

分 类 号：TD712[矿业工程—矿井通风与安全]