PURPOSE: To obtain a combustion method, through which NOx in exhaust gas can be reduced efficiently, by a method wherein a plurality of burners and an after air port disposed above the burners are set up into a furnace, the air ratios of each burner are made to reach 1 or less, exhaust gas is reduced and burnt while the quantity of fuel injected just under the after air port is increasd relatively and the oxidation of radical products is inhibited.
CONSTITUTION: The quantity of fuel injected just under the after air port 5, i.e. the amt. of injected fuel 15 at just under the upper-stage burner in this case is made more than that of a lower section, the quantity of radicals generated by the upper-stage burner 4 is increased, and a denitration reaction is executed effectively. The quantity of fuel injected in the upward direction of the upper-stage burner 4 is increased in consideration of involute air from the front after air 5 and the quantity of fuel injected in the downward direction is reduced in the denitration reaction, thus increasing the quantity of radicals generated in the upper-stage burner 4. That is, the denitration reaction is executed effectively by giving a bias of the quantity of fuel injected in the vertical direction of the upper-stage burner 4. The quantity of fuel injected from the upper-half section of the upper-stage burner 4 may be increased while the quantity of fuel injected from a lower-half section may be reduced in fuel supplied just under the after air port. It is preferable that the air ratio of the upper-stage burner or the burner corresponding to said burner is made to reach 0.4W0.6 which is suitable for the denitration reaction.
JPS5390023 | TWO-STAGE COMBUSTION FURNACE |
JP2002213714 | COMBUSTION DEVICE |
JPS62258909 | BURNER |
MASUKO SHIYOUICHI
UEMURA TOSHIO
MORITA SHIGEKI
MITA TAKEO
MIGAKI HITOSHI