CO₂ Capture from\na Binary CO₂/N₂ and a Ternary CO₂/N₂/H₂ Mixture by PSA: Experiments and Predictions

Abstract

The\nresults of pressure-swing adsorption experiments performed\nin a two-column setup are presented, as a way of validating a model\ndeveloped to design and optimize cyclic adsorption processes. The\nexperiments were conducted using a commercial activated carbon as\nthe sorbent and an adsorption pressure of 20 bar. Two feed mixture\ncompositions were studied: a binary CO₂/N₂ mixture\nrepresentative of a flue gas and a ternary CO₂/N₂/H₂ mixture representative of the product stream of air-blown\nautothermal reformers. During the experiments, the temperature was\nmeasured at five locations along the center of each column, along\nwith the pressure, feed flow rate, product composition, and high-pressure\nproduct flow rate. A one-dimensional, nonisothermal, nonequilibrium\nmodel was used to simulate the experiments in a fully predictive manner.\nThis model was previously validated in breakthrough experiments as\nwell as PSA experiments using a binary CO₂/H₂ mixture. A thorough analysis of the experimental results and comparison\nwith the simulation results showed that the model is fully capable\nof handling rather different feed compositions while still predicting\nsatisfactorily the temperatures within the column, the product composition,\nand the overall process performance for a variety of process configurations\nand operating conditions.