Scholarlink

<p>The low permeability and complex multi-field coupling effects in non-producible coal seams pose significant challenges to efficient CO₂-enhanced coalbed methane (CO₂-ECBM) recovery. This study establishes a fractal dual-porosity hydro-mechanical-thermal (HMT) coupling model to investigate the synergistic effects of coal seam heterogeneity, CO₂ injection parameters, and thermophysical property variations on CH₄ production and CO₂ sequestration. The model integrates fractal theory to characterize matrix and fracture microstructures, competitive adsorption dynamics, and temperature/pressure-dependent gas properties (density, viscosity, thermal conductivity). Validated against field data from the Qinshui Basin and numerical benchmarks, the results reveal that: (1) fractal characteristics, particularly fracture length (<i>l</i>ₘₐₓ) and fractal dimension (<i>D</i><sub><i>f</i></sub>), dominate permeability evolution, with <i>l</i>ₘₐₓ increasing by 33% enhancing CH₄ production by 65% and CO₂ storage by 68.6%; (2) CO₂ injection pressure is the most critical operational parameter, where raising pressure from 1 to 6 MPa boosts CH₄ yield by 310% and CO₂ storage by 588%, whereas temperature effects are secondary; (3) neglecting thermophysical parameter variations with temperature/pressure overestimates CH₄ production by up to 75%. The proposed model provides a paradigm for optimizing CO₂-ECBM in heterogeneous coal seams, emphasizing the necessity of microstructure characterization and adaptive injection strategies for achieving carbon-neutral energy extraction.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Fractal Dual-Porosity Modeling and Simulation of CO2 Sequestration and Enhanced Coalbed Methane Production in Non-producible Coal Seams

  • 期刊论文

  • 发表日期：

    2025年8月27日

查看全文
  • Zhiqi Li,
  • Peng Hou,
  • Siyuan Wang,
  • Xin Liang,
  • Chuanqi Zhu,
  • Quansheng Liu,
  • Feng Gao

摘要

The low permeability and complex multi-field coupling effects in non-producible coal seams pose significant challenges to efficient CO₂-enhanced coalbed methane (CO₂-ECBM) recovery. This study establishes a fractal dual-porosity hydro-mechanical-thermal (HMT) coupling model to investigate the synergistic effects of coal seam heterogeneity, CO₂ injection parameters, and thermophysical property variations on CH₄ production and CO₂ sequestration. The model integrates fractal theory to characterize matrix and fracture microstructures, competitive adsorption dynamics, and temperature/pressure-dependent gas properties (density, viscosity, thermal conductivity). Validated against field data from the Qinshui Basin and numerical benchmarks, the results reveal that: (1) fractal characteristics, particularly fracture length (lₘₐₓ) and fractal dimension (Df), dominate permeability evolution, with lₘₐₓ increasing by 33% enhancing CH₄ production by 65% and CO₂ storage by 68.6%; (2) CO₂ injection pressure is the most critical operational parameter, where raising pressure from 1 to 6 MPa boosts CH₄ yield by 310% and CO₂ storage by 588%, whereas temperature effects are secondary; (3) neglecting thermophysical parameter variations with temperature/pressure overestimates CH₄ production by up to 75%. The proposed model provides a paradigm for optimizing CO₂-ECBM in heterogeneous coal seams, emphasizing the necessity of microstructure characterization and adaptive injection strategies for achieving carbon-neutral energy extraction.