抄録
CO2 adsorption simulation technique was built and implemented to clarify the performance determinant of PTSA CO2 adsorber. In the simulation, a CO2 adsorber was connected with a methanation reactor which converted CO2 and H2 to CH4. Exothermal heat of this methanation reaction was recovered by oil and then used as the energy of temperature swing at the CO2 adsorber. The CO2 adsorber was composed of 4 towers; adsorption, preheating, desorption and cooling. Each tower featured shell and tube design that was high heat exchange performance. Configuration of tubes and amount of the energy used for depressurization were investigated using the simulation. The results showed that CO2 recovery ratio was determined only by the average temperature at the end of the adsorption cycle and desorption cycle, as far as the input energy for depressurization was the same. CO2 recovery ratio depended on the configuration of tubes, because the average temperature was varied. When the diameter was too small, desorption average temperature was low because the heat capacity of adsorbents was small compared with that of pipes. On the other hand, when the diameter was too large, adsorption average temperature was high because eliminating adsorption heat at the center of the tube was difficult. These tendencies rise with decreasing CO2 recovery ratio.
