A PULVERIZED COAL TANGENTIAL FIRING DEVICE OF LOW NOX EMISSION

摘要

A tangential pulverized coal combustion device for low NOX emission includes a furnace hearth, on four conners of a main combustion of which primary air nozzles (4) and secondary air nozzles (5) are alternatively arranged. The axes of the primary air nozzles (4) or secondary air nozzles (5) which are in the same horizontal plane are tangent to an imaginary tangent circle whose center is coincided with the center of the furnace hearth. At least one group of overfire air nozzles is provided on the four walls of the furnace hearth above the primary air nozzles(4) and the secondary air nozzles (6). Each group of overfire air nozzles includes four overfire air nozzles (6) that are provided on the each wall of the furnace hearth and in the same horizontal plane. The axes of the overfire air nozzles in same group are tangent to an imaginary tangent circle whose center is coincided with the center of the furnace hearth. The combustion device avoids high content of the combustible material in flying ash caused by the integral air classification technology, avoids large deviation in the speed and temperature of smoke gas at the outlet of the furnace hearth, and achieves low emission of nitrogen oxides.