Oxygen-Enriched Gasification of Dried Sewage Sludge, Refuse-Derived Fuel, and Their Cogasification in a Laboratory-Scale Fluidized Bed

Abstract

Oxygen-enriched gasification of single-feed refuse-derived fuel (RDF) and dry sewage sludge (DSS) in a laboratory-scale fluidized bed was investigated. The optimal temperature, equivalence ratio (ER), and oxygen concentration of RDF and DSS gasification were 800 °C, 0.292, 50% and 750 °C, 0.321, 44.7%, respectively. The low heating values (LHVs) and cold gas efficiency (η values) of syngases from RDF and DSS were 6.79 MJ/Nm 3 , 53.0% and 6.51 MJ/Nm 3 , 49.2%, respectively, under optimal conditions. To improve the quality of DSS syngas, the effect of the RDF mixing ratio on RDF and DSS cogasification was investigated at 800 °C, with an ER of 0.321 and an OC of 44.7%. The gas yield increased continuously with increased RDF mixing ratio, and η rose to 55.0% with relatively high LHV of producer gas at a 25% mixing ratio of RDF.