GRATE FIRING OF PEAT FUELS
Combustion characteristics of peat are outlined, and an attempt is made to show that higher specific combustion rates must lead to more intense and more complete burning, with a consequent reduction in furnace volume and in excess air.
Ignition characteristics are also described. While burning rates of peat are limited only by considerations of ash carry-over, ignition rates are relatively slow. Underfeed ignition, which occurs in the underfeed stoker and the conventional chain-grate is not suitable for peat.
Two systems have found successful for peat-burning and these involve overfeed. The coking stoker (a modified coal stoker) and the screw stoker specially developed for peat are described.
Other systems which seem to offer promise for peat combustion but are not used (fluidised bed and spreader firing) are mentioned and their likely performance assessed.