GB1464410A - Fluidized modular combustion and gas cleaning unit - Google Patents

Abstract

1464410 Fluidized bed combustion units J HUNTER 22 Nov 1974 50661/74 Heading F4B A fluidized bed combustion unit has a rotatable distributer plate 34 with a number of blanked-off upstanding pipes 30 each with a number of radial jets to convey fluidizing air from chamber 52 into the bed, the bed being surrounded by an annular heat-exchange jacket 35 connected to pipes 23 traversing the bed, a fluid, e.g. water, being circulated by pipes 4 and 6 to remove heat from the bed and keep it at a temperature below the fusing temperature of the bed material. The fuel, which may be pulverized coal, is blown into the bed through radially directed jets 24 connected to a ring main 25. Excess bed material spills through openings 22 and is removed by suction through pipe 21. The combustion unit may have on top of it a unit 19 having an exit 18 for the combustion gases and a number of heat exchange pipes 11 for heating air entering at 7 and leaving at 8. The combustion gases are cleaned in a unit (Fig. 2, not shown) consisting of a number of cyclones or filters which separate dust and carbon particles and pass it through a toothedwheel feeding device to an air injector which returns it to the bed via the fuel main 25. The injected air may be hot or cold. If hot it is the air heated in the section 19. The cleaned gases return through a port 17 in an economizer section 14 where heat exchange pipes 13 remove further heat before it passes to the flue 12. The fuel may alternatively be oil or coal dust mixed with oil pumped through the main 25. The distributer plate 34 supporting the bed, turns on bearings 28 and rotates the whole bed. The air supply to the bed may be adjusted to control the heat generation or part of the plate 34 may be covered by a stationary shutter causing the bed to collapse in that region.