Abstract

Numerical study of underground coal gasification (UCG) is conducted by adopting a porous medium approach. The components of UCG are modeled, including the reactions in UCG, fluid flow in UCG and cavity growth mechanisms. The advantages and disadvantages for the porous medium approach of existing 3D porous media basis hydrocarbon simulator are discussed. By using STARS, three case studies of 1D model, simultaneous independent reaction model for pyrolysis and 3D large scale model are performed. Some important conclusions are obtained: single-step decomposition model is economic, but not precise due to the same temperature range of evolution for all species and the same onset of evolution of all species.