Implications of carbon dioxide sorption kinetics of low rank coal

This study appraises the dynamic of porosity and permeability measurement of the coal for reservoir modelling during gas production. Known as one of the main target areas for coalbed methane (CBM) production and potentially in integrating testing methodology, these measurements were carried out on low rank coals. During the testing, the pore pressure was varied at each pressure in stepwise with the adsorption equilibration. The gas content of the core sample was estimated until equilibration of the system and the sample of swelling in response to adsorption was measured. By employing newly achieved measurements, CT scan and acoustic emission wave methods, this study determines the porosity and permeability evolution which acts an important role in the dynamic changes in CO₂ sorption kinetics of coal. Permeability can be calculated by applying a pressure difference between both end sides of inlet-outlet of a certain direction according to Darcy's law. While the Kozeny-Carman is an empirical equation influenced by several parameters such as total porosity, specific surface area, pore shape, tortuosity, and porosity to determine the permeability. By merging both approaches, empirical and laboratory method, the sorption kinetics of coals and other controlling factors are also counteracted.