The influence of particle sizes on the design of combustion equipment

Abstract

Besides moisture content, particle size and shape are important factors to be considered when evaluating the usefulness of biomass residues. Particle geometry is especially important when the use of biomass residues for combustion purposes is envisaged. With some residues, such as sawdust, effective combustion is difficult without some form of mechanical or pneumatic agitation to thoroughly mix air and combustible materials. The introduction of a new breed of low-cost multi-fuel industrial combustion devices and domestic stoves allows a variety of coarse to fine biomass fuels to be acceptable in separate or mixed form. Because of these devices, the fuel purchaser will be able to obtain fuels from a wider range of biomass residue suppliers, and at a better price. Consideration must also be given to the increased use of whole tree-chips obtained from forest residues or harvested invader bush. Greater use of these chips will reduce the need to cut down ecologically valuable indigenous trees for firewood.