 Adsorption isotherms under different pressures and temperatures can be represented by a 2D surface. Adsorbed methane density in shales is a function of pressure and temperature. Maximum adsorption uptake of shales is independent of temperature and pressure. Isosteric enthalpy and entropy depend on surface coverage and temperature.

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Understanding the dynamic response of coal to carbon dioxide sorption is crucial for optimizing carbon dioxide sequestration in unmineable coal seams and enhanced coalbed methane recovery. In order to explore the adsorption kinetics of carbon dioxide in coal, 15 isothermal adsorption tests were conducted on bituminous and sub‐bituminous coals at 50°C for increasing equilibrium pressures (up to 4 MPa). The pseudo‐second order (PSO) model is introduced to approximate the carbon dioxide sorption kinetics in coal, and the kinetics properties are then investigated via the PSO model. The linear relationship between (t/q) and (t) is validated and confirmed with a high correlation coefficient (>99%). The kinetics parameter, k2, decreases with both increasing equilibrium sorption pressure and increasing pressure difference. The sorption equilibrium content, Qe, in each sorption stage depends on both the final equilibrium pressure and the pressure difference. Based on the relationship between sorption content and time, the sorption content for different pressure ranges is predicted using different time intervals. The analysis indicates that the adsorption process for carbon dioxide in coal is a combination of both bulk diffusion‐controlled and surface interaction‐controlled processes; the former dominates the initial stage while the latter controls the majority of the overall process. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd

This work proposes a novel and cost-effective approach to determine coalbed methane (CBM) production and composition from individual coal seams in a multi-zone completed CBM well. The novel method uses water to cover individual coal seams in a low pressure CBM well followed by an Echometer fluid level survey to determine the water level. Corresponding gas flow measurements and natural gas chromatography analysis are used to determine gas production and composition from unique zones. A field test using this technology is conducted in Central Appalachia for a multi-zone CBM well containing 18 coal seams. Test results show that the shallow coal seams contribute the majority of the total CBM production in this multi-zone well, and the deeper coal seams contain more heavy hydrocarbons like ethane and propane.

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