Detailed kinetics in the mathematical model of fixed bed gasifiers

This work presents a general mathematical model of a fixed bed gasifier, where both the transport resistances and the chemical kinetics are important at the reactor and the particle scale. Pyrolysis and gasification of the solid fuel (coal, plastics, biomasses or wastes) is only the first step of the whole process. Successive gas phase reactions of the released species are described with a detailed kinetic scheme. Furthermore, an accurate description of heat and mass transport between gas and solid phases allows a proper characterization of combustion and gasification of the solid fuel. This work summarizes several facets of this problem with examples and validations. Examples relating to coal and biomass gasification allow evaluating the feasibility and limitations of the proposed approach.