Numerical study of the dynamics of synthesis gas adsorption separation

A numerical study of the dynamics of pressure swing adsorption process for synthesis gas separation and hydrogen concentration was carried out. The influence of regime parameters (compressor and vacuum pump outlet pressures, duration of the "adsorption-desorption" cycle, backflow coefficient) and design parameters (height of the adsorbent bulk layer and the internal bed diameter) on the recovery and purity of hydrogen, plant performance in a given range of changes in the temperature, composition and pressure of the initial gas mixture was studied. It is found that when the hydrogen content decreases from 68 to 48 vol. % and a simultaneous increase in the carbon dioxide content in the initial gas mixture from 27 to 47 vol. % required hydrogen purity value at 99.99 vol. % can be achieved by reducing the pressure at the outlet of the vacuum pump from 0.75?105 to 0.5?105 Pa. At the same time, the duration of the adsorption stage increases from 120 to 150 seconds, and the degree of hydrogen extraction decreases from 55 to 52% due to an increase in the proportion of the flow selected for the regeneration of the adsorbent. Increasing the temperature of the initial gas mixture from 293 to 323 K leads to the need to reduce the duration of the adsorption stage from 148 to 42 s due to a decrease in the equilibrium concentrations of carbon dioxide and monoxide in the adsorbent.