To improve an igniting and flame holding characteristic of fine powder coal and reduce nitrogen oxides by a method wherein mixing of a mixture fluid and surrounding air is delayed and a high concentration area of fine powder coal is assured to be wide.
A liquid fuel infection nozzle 1, a fine powder coal flow passage 2, a slow speed secondary air flow passage 3 and a high speed third air flow passage 4 are arranged in sequence from a center of a plurality of nozzle flow passages arranged coaxially. Then, deflector plates 9 and 10 widened in a loud- speaker shape are mounted in an annular form in such a way that each of air at an outer circumference of each of the plates may be widened in an outward direction so as to cause mixing of secondary air flow 33 and third air flow 34, an ignition flame holding region 41 is formed while a high concentration of fine powder coal is being kept and at the same time a wide reducing area 42 is formed near the burner. With such an arrangement as above, it is possible to reduce an amount of nitrogen oxides.
NOMURA SHINICHIRO
BABA AKIRA
MEGURI NOBUYASU
SHOJI KAZUNORI
Next Patent: FUEL PREMIXING DEVICE AND GAS TURBINE COMBUSTION DEVICE