PULVERIZED COAL FIRING EQUIPMENT AND METHOD OF OPERATING THE SAME

PURPOSE:To greatly reduce the costs for equipments and fuel without requiring auxiliarily firing kerosine, gas, heavy oil and the like by providing an ignition burner, and a pulverized coat burner for low load which use electric type heat resistance heating elements capable of increasing the temperature to 1,000 deg.C or higher. CONSTITUTION:An ignition burner 25 for directly igniting pulverized coals and a pulverized coal burner 24 for a low load are provided in a pre-firing device 23 provided in the furnace 21 of the boiler. An electric type heater 26 is provided in the ignition burner 25, and the temperature of combustion air is raised to a temperature in the range of 300-350 deg.C. Power is supplied to a heating element 30 provided at the tip end of the burner 25 thereby to raise the temperature of the heating element to a temperature in the range of 1,000-1,100 deg.C to set the ratio of the coal feed quantity to combustion air C/A at 0.5 or more, the air flow speed at the outlet of a burner nozzle at 10m/s or less, the particle size of pulverized coals at 200 meshes or less. The pulverized coat burner 24 for a low load is started after confirming that the brick surface temperature of the pre-firing chamber is 1,000 deg.C or more. By these procedures, a pulverized coal exclusively firing operation, which makes the generation of unburnt parts even at the low load at the time of starting, can be performed.