BLEND COMBUSTION METHOD OF FUEL COAL FLY ASH FOR BIOMASS CIRCULATING FLUIDIZED BED BOILER AND DEVICE THEREOF

摘要

A blend combustion method of fuel coal fly ash for a biomass circulating fluidized bed boiler (9) and a device thereof. In the method, the fuel coal fly ash is jetted onto the bottom of a dense phase combustion zone (13) bed layer inside the biomass circulating fluidized bed boiler (9) so that the fuel coal fly ash is mixed with incandescent biomass bed materials in a bubble state or a turbulent fluidized state to generate intensive heat and mass transfer and temperature increase with violent rolling and friction, thereby abrading away ash shells on the external layer of the fuel coal fly ash to expose unburned residual carbon black core therein, and finally the fuel coal fly ash is completely combusted in the dense phase combustion zone (13) and a dilute phase combustion zone (14). The device is mainly composed of a fuel coal fly ash storage bin (1), a rotary material feeding device (2), an ejector (3), an air blower (5), a transporting pipeline (6), a bottom feeding abrasion resistant spray nozzle (8) and so on, which are used with the biomass circulating fluidized bed boiler (9). By means of the device, the fuel coal fly ash can be recycled into the biomass circulating fluidized bed boiler (9) for fully combustion again to perform secondary power generation, thereby effectively reducing the amount of a biomass fuel, increasing the power generation capacity of unit fuel, and can reduce emission of coal combustion pollutant.