采矿与安全工程学报 ›› 2012, Vol. 29 ›› Issue (4): 505-510.

• 论文 • 上一篇    下一篇

煤层气注热开采的热-流-固耦合作用分析

  

  1. 1. 中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏  徐州  221008 2. 中国矿业大学力学与建筑工程学院,江苏  徐州  221116;3. 中国矿业大学理学院,江苏  徐州  221116
  • 收稿日期:2011-12-07 出版日期:2012-07-15 发布日期:2012-05-23
  • 作者简介:张凤婕(1986-),女,河北省石家庄市人,研究生,从事煤层气开采中的多物理场耦合方面的研究。 E-mail:zhangfengjie2007@163.com Tel:15950674336
  • 基金资助:

    深部岩土力学与地下工程国家重点实验室开放基金项目(SKLGDUEK1001)

    国家自然科学基金项目(50974115)

Coupled Thermal-Hydrological-Mechanical Analysis of Exploiting Coal Methane by Heat Injection

  • Received:2011-12-07 Online:2012-07-15 Published:2012-05-23

摘要: 如何提高煤层气产量是目前煤层气开采研究中的重要课题。煤层气在煤层孔隙中主要以吸附状态存在,提高煤层温度可以促使气体由吸附态转变为游离态,增加其渗流扩散能力。根据热弹性力学、非线性达西渗流理论和多孔介质热力学原理,对在煤层中注热提高煤层气产量的机理进行了系统研究,建立了包含煤的变形方程、气体渗流方程、热传导方程的热流固多物理场耦合数学模型。在此基础上利用COMSOL Multiphysics 数值软件,对耦合模型进行了数值求解,结果表明:注热后煤层温度升高可以促进煤层气解吸、提高煤层渗透率,增加煤层气产量。研究成果可为煤层中注热开采煤层气的工程实践提供相应的理论基础。

关键词: 热流固耦合方程, 双重孔隙介质, 煤层气开采, 渗透率

Abstract: Improving coal methane production  is an important subject in the current research for coal methane exploration.Some researches show that, coal methane exist mainly as adsorption state in coal seam pores.Improving coal seam temperature can make gas change into free forms from adsorption forms,and improve its seepage-diffusion ability. According to the thermoelasticity, nonlinear Darcy seepage theory and porous medium thermodynamics principle, this paper studied the mechanism of improving coal methane production by heat injection. The multiphysical coupling equations were been established, including coal deformation equation,gas percolation equation and heat transfer equation. By means of COMSOL numerical software ,the numerical solution of coupling model was been proceeded .The results demonstrated that rising injecting heat could promote desorption of coal methane, improve the permeability, achieve the purpose of improving coal methane production. The research results could provide corresponding theoretical basis for engineering practices of exploiting coal methane by heat injection.

Key words: thermal-hydrological-mechanical coupling, dual porosity medium, coal methane exploition, permeability