Gasification of a dried sewage sludge in a laboratory scale fixed bed reactor

The paper present study on the air gasification process of dried sewage sludge. Parameters such as air ratio lambda=0.12 divided by 0.27, air temperature t=50 degrees C divided by 250 degrees C and molar fraction of O-2 in gasification agent z(O2)=0.21 and z(O2)>0.2) were found to influence on the syngas parameters: Lower Heating Value (LHV) and composition. The results indicate that the syngas LHV was found to decrease with increase air ratio for all analyzed cases. Increasing O-2 concentration in gasification agent increased the temperature, which tended to favour the formation of smaller molecular components in the gas mixture. Thus, the enriched air medium produced a gas with a higher LHV. In contrast to conventional gasification, a process with a preheated gasification agent causes that the flux of heat necessary to support endothermic gasification reactions is producing more effective. As a result, H-2 and CO production is promoted. (C) 2015 The Authors. Published by Elsevier Ltd.