LOW NOX COMBUSTION DEVICE BURNING FINE COAL POWDER

摘要

PURPOSE:To reduce NOx contained in waste gas as well as char by a method wherein a coal portial combustion furnace is projected at an outer circumference corresponding a space between a main burner and an after-air supplying port of an industrial furnace. CONSTITUTION:A cylindrical coal partial combustion furnace 12 is arranged to project at a corresponding outer circumference between the second main burner 3 and an after- air supplying port 10 of an industrial furnace 1, a base end of the furnace is formed with a gas feeding port 13 communicating with the industrial furnace 1 and in turn an outer projecting end of the furnace is provided with a denitrification burner 9. Within the coal partial combustion furnace 12 is formed a partial combustion chamber 14 in correspondence with a space between the denitrification burner 9 and a gas feeding port 13, and a temperature in the combustion furnace 12 is excessively increased with an air ratio of 0.5-0.8 in respect to fine powder coal, resulting in that ash included in the fine powder coal is completely melted. When the coal partial combustion furnace 12 is of a cyclone system, the molten ash is influenced by a strong circulation flow of gas and adhered to the wall of the furnace. With this arrangement, the molten ash is selfcoated to the inner wall of the combustion furnace 12 so as to extend the life of the heat insulating refractory material.