COMBUSTION MODELING OF A BIOMASS PACKED BED IN MOVING GRATE FURNACES

摘要

This paper represents the result of an accurate analysis of biomass thermal conversion process thatallowed the development of a biomass combustion mathematical model. It is part of a more extensive work thatconcerns the study and the characterization of biomass combustion process. The aim of the work can be reassumed inthe following points: 1) development of a mathematical model to simulate biomass combustion, 2) abatement ofpollutant emission through highlighting correlations among combustion process parameters, biomass characteristics(chemical and physical) and mechanisms of pollutant formation, 3) combustion investigation over a wide plantbiomass collection, 4) development of more efficient combustion and energy recovery systems. In such a part ofwork, a two 2-D steady-state model of biomass packed bed combustion is presented. It considers thermal conversionof biomass in a moving grate furnace. The model takes into account moisture evaporation, devolatilization of volatilematter, char combustion, gas fluid dynamics in porous bed, convective, conductive and radiative heat transfer.Composition and velocity field of gas phase above the biomass bed are presented. These results are structured to beused in a multidimensional CFD model of gas phase combustion.