Simulation of Fluid Flow Behaviour during Co2 Sequestration using Comsol Multiphysics In Coal Bed

Coal beds are an extremely complicated porous medium with characteristics of heterogeneity, dual porosity and stress sensitivity. In the past decades great achievements have been made to the simulation models of pressure depletion coal bed methane (CBM) recovery process and CO2 sequestration and enhanced coal bed methane (ECBM) recovery process. Due to the assumptions and over simplifications analytical models have limitations or problems in application. In this work, an effort has been made to study the behaviour of fluids i.e. CO2 and methane inside of coal and the analysis has been carried out to study their velocity and pressure variations using COMSOL Multiphysics. Coal contains both cleat and porous structure. Cleats are the natural fractures in coal and pores are the important factors for migration of fluid inside coal. Two separate models are developed to understand the fluid flow behaviour in both cleat and porous structure of coal.