Fluidized bed residential heating system

摘要

A fluidized bed combustion system particularly suitable for use in a residential heating system comprising a fluidized bed combustor housing a combustion chamber wherein crushed fuel is burned to generate hot flue gas, a heat exchanger disposed outside of the combustor in the flow path of the flue gas, a particulate collector for removing fine particles entrained in the flue gas before the flue gas is vented to the atmosphere, and an induced draft fan for venting the flue gas to the atmosphere and drawing fluidizing air and recirculated flue gas through the combustion chamber. The combustor is uncooled and heavily insulated so as to provide a substantially adiabatic combustion chamber therein in order to minimize heat loss therefrom. Electric heating means are disposed within the fluidizing region of the combustion chamber to provide the capability of heating the slumped bed during shutdown to maintain bed temperature above the ignition point. The operating temperature of the bed is maintained below the ash softening temperature of the coal by selectively controlling the amount of flue gas recycled.