A CO2 adsorption simulation technique was built and implemented to clarify the design requirements of PTSA CO2 adsorption. In the simulation, a CO2 adsorber was connected with a methanation reactor, which converted CO2 and H-2 to CH4. Exothermal heat of the methanation reaction was recovered with oil and then used as the energy for temperature swing in the CO2 adsorber. The CO2 adsorber featured a shell-and-tube design that has high heat exchange performance. Configuration of the adsorber, i.e., tube number, diameter, length, thickness and oil flow channel width, was investigated using the simulation. The results showed that the CO2 recovery ratio was determined by the cooling performance of the adsorption process and the heating performance of the desorption process. The cooling performance depended on the specific surface area, defined as the heat exchange area divided by adsorbent volume. The heating performance depended on the heat capacity ratio, defined as the adsorbent heat capacity divided by total adsorber heat capacity. Thus, CO2 recovery ratio was determined by the specific surface area and heat capacity ratio of the CO2 adsorber.