Controlling the carbon dioxide (CO₂) concentration in the atmosphere of chambers/rooms is a necessity for various applications. The adsorption-desorption using solid adsorbent is often considered the best technique to actively control CO₂ concentration in closed space. Activated carbon is extensively used in CO₂ adsorption due to its economic cost, high adsorption capacity and easy availability. This study presents an experimentally validated numerical approach to demonstrate the removal of CO₂ using activated carbon through cyclic adsorption and desorption processes. The numerical model simulates the heat and mass transfer phenomena in the porous media to determine the maximum CO₂ removal rate from solid activated carbon with varying operating parameters. The effective cycle time for maximum CO₂ removal is determined based on CO₂ removal per hour through a scrubber in daily application. The CO₂ removal rate can be maximized in a cyclic adsorption-desorption process by operating in a partial capacity mode (based on the adsorption kinetics and uptake curve), instead of trying to utilize the nearly full adsorption-desorption capacity of the bed in each cycle. Increasing the thickness of activated carbon leads to greater CO₂ removal per cycle with increasing pressure drop, while it also prolongs the adsorption and desorption cycle time.
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