| 摘要 |
PURPOSE:To lengthen a staying time for which ash is staying in the layer of a fluidized bed and to increase a combustion ratio in the layer, by a method wherein ash, containing an unburnt component, is precipitated in water and is formed into an arbitrary size, or is supplied in the form of slurry to an auxiliary fluidized-bed combustion furnace. CONSTITUTION:In a main fluidized-bed combustion furnace 1, pulverized coal is fed through a coal charge port 6 and the air is fed through a vent pipe 9 by means of an air diffuser plate 3. In the furnace 1, fuel is burnt, a fluidized bed is formed, and steam is generated in a water pipe 7. Fly ash, produced occasioned by combustion, flies in a condition to contain an unburnt component to a precipitating water tank 3 through a dust collector 2 by means of a communicating passage 10, and is settled in water 11 and is precipitated in a tank base 12. Thereafter, ash containing the precipitated unburnt component is removed to the outside from said tank 3, and is granulated into a proper size by the use of a granulator 4. Instead of granulation, the ash may form slurry. Thereafter, the granulated ash is fed to an auxiliary fluidized-bed combustion furnace 5 to reburn it. |
