A SCRAPPER-ASSISTED FUEL FEED NOZZLE DEVICE FOR FEEDING HIGH MOISTURE FUEL IN THE BUBBLING FLUIDISED BED COMBUSTION (BFBC) BOILERS

摘要

The invention relates to a scrapper-assisted fuel feed nozzle device for feeding high- moisture fuel in Bubbling Fluidised Bed combustion (BFBC) boiler, comprising at least one accelerating nozzle (8) for transferring fuel (coal) supplied through a coal feed line (9), the nozzle (8) accelerating a low pressure air supply to convert the pressure head to a velocity; a recovery nozzle and diffuser combination (14, 15) collecting the high velocity air-fuel mixture and recovering the pressure head; an optimized mixing chamber (10) for promoting the mixing of the air-fuel; and a transport line (16) for transportation of the air-fuel mixture for feeding into the bubbling bed combustor, the coal feed line (9) is having an identical cross-section as that of the transport line (16) which is achieved by optimizing the configuration of the atleast one accelerating nozzle (8), and a scrapper means (12, 17) disposed into the transport line (16) before the recovery nozzle / diffuser (14, 15) which is connected to a driving means (13), the driving means (13) being activated at a predetermined frequency corresponding to the data relating to frequency of blockage experience in the past.