Abstract: An apparatus for supporting and starting up a fluidized bed in which a grate is disposed in a housing for receiving a single bed of particulate material, portions of which are combustible. The interior of the housing below the grate is divided into a plurality of compartments, and an air damper is disposed in each for selectively controlling the flow of air through the compartments and through the respective portions of the grate to selectively fluidize the corresponding portions of the bed of particulate material. A start-up burner is provided for igniting that portion of the combustible portion of the bed of particulate material extending above one of the compartments and additional combustible particulate material is selectively supplied to the portions of the bed.

Abstract: A coal feed system for use in a fluidized bed in which a grate is supported in a housing and is adapted to receive, on its upper surface, a bed of particulate material including a combustible fuel. Air is passed through the grate and into the bed to fluidize the particulate material. The particulate fuel material is separated externally of the bed into a relatively coarse material which is distributed over the upper surface of the bed and a relatively fine material which is distributed into the bed below the upper surface.

Abstract: A steam generator in which a high-velocity, combustion-supporting gas is passed through a bed of particulate material to provide a fluidized bed having a dense-phase portion and an entrained-phase portion for the combustion of fuel material. A first set of heat transfer elements connected to a steam drum is vertically disposed above the dense-phase fluidized bed to form a first flow circuit for heat transfer fluid which is heated primarily by the entrained-phase fluidized bed. A second set of heat transfer elements connected to the steam drum and forming the wall structure of the furnace provides a second flow circuit for the heat transfer fluid, the lower portion of which is heated by the dense-phase fluidized bed and the upper portion by the entrained-phase fluidized bed.