Biogas upgrading to fuel grade methane using pressure swing adsorption: Parametric sensitivity analysis on an industrial scale

Biogas upgrading to fuel-grade methane employing PSA technology is examined using a one-dimensional binary mixture comprising of CH4 and CO2, heat and mass balance model through Aspen Adsorption TM version 10 and Aspen Hysys simulation. Comparison between the experimental data over a bed of silica gel and the simulated results reveal that the methane and carbon dioxide breakthrough curves and temperature responses at various positions along the adsorption bed is in a good agreement. The effects of design parameters such as feed flowrate, adsorption step duration, axial dispersion coefficient, and bed dimensions at an industrial scale on methane purity and recovery are analyzed. Aside from silica gel, five more adsorbents including CMS-3 k, zeolite-NAUSY, Zeolite KZ10-04, porous polymeric beads and zeolite 5A were employed and their process performances were evaluated. CMS-3 K records the highest biomethane purity and recovery of 97.165% and 86.2%, respectively which meets the biogas quality standards. The developed model has great competence for making prediction of biogas upgrading performance of PSA cycle with impressive ability to manage the effect of heat generated on adsorption properties.