Waste-to-Energy Technologies Applied for Refuse Derived Fuel (RDF) Valorisation

摘要

Refuse Derived Fuel (RDF) is a solid fuel made after basic processing steps or techniques that increase the calorific value of municipal solid waste (MSW), commercial or industrial waste materials. Therefore, energy production from RDF can provide economic and environmental benefits as it reduces the amount of wastes sent to landfill and allows the energy recovery from a renewable source. In this work, it was studied the application of waste-to-energy technologies to RDF valorisation, namely pyrolysis and gasification. This study intended to evaluate the effect of temperature and different technologies (gasification and pyrolysis) in gas production, gas composition and mass conversion of RDF. Experiments of RDF gasification and pyrolysis were performed in a laboratory scale fixed bed gasifier, under different conditions. The effect of reaction temperature was studied at 450, 600 and 750 ℃ in pyrolysis experiments and at 750 ℃ and 850 ℃ in gasification. Results showed that, for the same operational conditions, pyrolysis was more efficient at 750 ℃. At this temperature, it was obtained a syngas of 11.2 MJ/m~3 and a specific gas production of 0.43 m~3 syngas/kg RDF. Results also proved that, for the same operational conditions, the rise of temperature improved gas production ratio (Nm~3/kg RDF), gas low heating value (LHV) and mass conversion. Regarding to gas production ratio the utilization of air at equivalence ratio (ER) of 0.6 induced the formation of 1.5 m~3 gas/kg RDF. Differently, steam gasification only allowed the production of 0.5 m~3 gas/kg RDF. Mass conversion and carbon conversion achieved almost 100% in air gasification at highest molar ratio.