Separation of CO_2/N_2 mixture by vacuum pressure swing adsorption (VPSA) using zeolite 13X type and carbon molecular sieve adsorbents

摘要

Separation of carbon dioxide in flue gases from the combustion equipment is one of the most serious concerns for industries and especially for the power plants which are the main producers of this pollutant gas. From the various separation methods, vacuum pressure swing adsorption (VPSA) process is attracted interest due to its lower energy consumption and high efficiency. A VPSA process was studied for the separation of a mixture of CO_2/N_2 (80% N_2 and 20% CO_2). Experiments were performed in an eight-step, four-bed setup using zeolite 13X and carbon molecular sieve (CMS) as adsorbents. Experimental measurements by the bench-scale system have been obtained in a pressure range of 2.7-4.7 bar, cycle times of 360-600 s, the product flow rate of 1-3 (lit/min), and temperature 30 °C. The effects of pressure, cycle time, and product flow rate were investigated. With using 560 s for a cycle time at 3.7 bar, the maximum purity of 97.6% was obtained for zeolite 13X adsorbent.