ABSTRACT
The combustion of solid fuel is based primarily on a gasification process, after which the resulting gases bum and deliver heat at temperatures between 1 200 and 1 800°C. Solid biomass fuel has to be dry to attain a high combustion quality. In the under-burning stoves only the lower part of the fuel charge is in a reaction, and if there is a hot secondary combustion chamber the environmental impact is low. Large furnaces are in use in Scandinavian countries, Austria, Switzerland, Canada, USA, West Germany, and in several developing countries where there are good potential sources of biomass for fuel. The components of solid fuels are important for the emission of specific chemical elements. A low moisture content in the fuel—between 16 and 30 per cent, depending on the type of furnace—is fundamental to low emission production and efficient operation.
