An experimental study of hydrogen production by gasification of biomass in the presence of a sorbent

The paper presents a novel technique that enhances the hydrogen yield of conventional biomass steam gasification. This is done by integrating the gasification and absorption reactions. The method involves steam gasification of a carbonaceous fuel (biomass) in presence of a CO 2 sorbent. Experiments were conducted by gasifying pine bark in presence of calcium oxide. The gasification was carried out at atmospheric pressure in the temperature range 500 – 700 ∘ C . The hydrogen yield, total gas yield and carbon conversion efficiency increased by 48.6%, 62.2% and 83.5%, respectively, in the presence of sorbent at a gasification temperature of 600 ∘ C . This was attributed to the reforming of tars and hydrocarbons in the raw product gas in presence of calcium oxide. The CO and CH 4 concentrations in the product gas were lower while using the sorbent. The calcium oxide played the dual role of sorbent and catalyst.