Abstract
Carbonization and gasification processes are being developed in Japan to convert sewage sludge into fuel. It is necessary to tailor these technologies in terms of thermal recovery, local conditions, costs, and hazardous materials. Therefore, we investigated the effect of the pyrolysis temperature on the composition and heating value of char, tar, and gas, and the rate equation for the production of hydrocarbon gas. We were able to recover about 70% of the low heating value of dry sludge cake as char at 573K. By contrast, at over 773K, both the yield and low heating value of char were decreased, and the recovery from char was inefficient. At 1173K, we were able to recover only about 36% of the low heating value of dry sludge cake as gas. The production of H2 and CO was increased with steam, and we were able to recover about 50% as gas.
