JPS57207719A - Burner for furnace - Google Patents

Abstract

PURPOSE:To equalize temperature distribution in the furnace by an arrangement wherein a control is effected so as to increase or decrease the flow speed of a combustion gas so that the moving amount of the combustion gas can be maintained at a constant value even if the combustion amount changes, thereby constantly securing recirculation or convection over the entire zone in the furnace regardless of the combustion amount. CONSTITUTION:A first and a second fuel supply chambers 7 and 8 are supplied with fuel from fuel guns 9, 14... and with combustion air from inlets 7b and 8b by means of fans 13 and 18. The chambers 7 and 8 mix thus supplied fuel and air and inject the resultant mixture into the furnace 1 through injection ports 7a and 8a. The injection port 7a injects a high speed mixture, whereas the injection port 8a injects a low speed mixture, the former accelerating the latter. The mixture burns advancing toward a backward wall 2b of the furnace 1 and then returns from the backward wall 2b and goes out of a smoke passage 4. If the combustion amount in the furnace 1 is relatively small, the combustion rate at the injection port 7a is increased to increase the moving amount of the combustion gas, whereas if the combustion amount is relatively large, the combustion rate is decreased. Thus the overall moving amount of the combsution gas is maintained substantially at a constant value.