Evaluation of a Water Scrubbing Process for Biogas Enrichment

Abstract

There has been an increasing interest in biogas production, storage and utilization, due to global warming concerns and the need for renewable energy. Raw biogas contains impurities (CO₂ and H₂S) which limits the energ y content and lowers the heating value. The use of upgrading processes to remove incombustible gases from raw biogas increases its methane content and energy capacity. Water Scrubbing, based on the physical effect of dissolving gases in liquid is a method of upgrading biogas. This study modeled and evaluated the enrichment parameters needed to achieve a minimum biogas purity of 95% using a step wise variation technique on CHEMCAD  modeling and simulation tools. Chemical Process simulation software tool, CHEM CAD, was applied for the simulation. The optimal  operating parameters for methane enrichment of 97.43% was obtained at 2.5atm inlet gas pressure, 1.2m 3 /hr gas flow rate and water flow rate of 12m 3 /hr. The findings indicate that water scrubbing may be a rea dy procedure for biogas enrichment.