Gasification of Refuse-derived Fuel (RDF)

Abstract

In this work, gasification of a fraction of municipal solid waste, MSW, generally separated from inorganic materials and biodegradable components, so called refuse-derived fuel (RDF), was studied by material characterisation methods, and modelling of an industrial scale process was presented. Composition of RDF was determined by the separation of a representative sample into its basic components (paper, foils, hard plastics, textiles). All components of RDF and also a representative mixed sample of RDF were studied by thermogravimetric (TGA) analysis, elemental analysis and bomb calorimetry to determine their proximate and elemental composition, and higher heating value. Industrial scale gasification process was studied by mathematical modelling and computer simulation. All techniques, gasification with air, gasification with oxygen and gasification with both oxygen and steam were investigated under different conditions. The RDF conversion of 100% was achieved by gasification with air at the air to RDF mass ratio of 3,2. The gas heating value was 4,4 MJ/Nm³. Gasification of RDF using oxygen enables production of gas with the heating value of around 10 MJ/Nm³ at the oxygen to RDF mass ratio of 0,65. By increasing the steam to RDF mass ratio, the content of H₂ and CO₂ increased, however, the content of CO, reactor temperature and gas heating value decreased.