Finite Element Analysis of the Subsidence of Cap Rocks during Underground Coal Gasification Process

Abstract:

This paper discusses the possible surface subsidence and deformation of the overlying rock during the underground coal gasification (UCG) process, which is an important part of feasibility studies for UCG operations. First coal seam roof movement and surface subsidence in the shallow UCG process were simulated by a finite element model coupled with heat transfer module in COMSOL. Numerical results from this model were compared with and in good agreement to the existing studies. This was followed by the development of model for deeper coal seam cases. The comparison of the numerical results from two models shows that surface uneven settlement in deep underground coal gasification is only 7% of that in shallow underground coal gasification.

• Periodical: Advanced Materials Research (Volume 859)
• Pages: 91-94
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.859.91
• Online since: December 2013
• Authors: Xiao Xiong Zha*, Hai Yang Wang, Shan Shan Cheng
• Keywords: Cap Rocks, Finite Element Model (FEM), Multi-Physics Coupling, Underground Coal Gasification

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