PURPOSE: To enable reducing of a concentration of NOx contained in pulverized coal combustion exhaust gas, by a method wherein NOx can be effectively reduced even under the presence of oxygen by utilizing an N compound, produced at the thermal decomposition of coal, for the reduction of NOx.
CONSTITUTION: A burner for a pulverized coal combustion consists of two pulverized coal nozzles 12 and 13, a secondary air nozzle 17, a tertiary nozzle 18, and an igniter 16. Most of fuel pulverized coal is jetted through a pulverized coal nozzle 12 for jetting pulverized coal and a fuel-air mixture comprising primary air for the conveyance and jet of the pulverized coal, a primary combustion region in a ratio of 1 or more is formed at a tip of a burner by means of the secondary air and the tertiary air jetted through the secondary air nozzle 17 and the tertiary air nozzle 18. With the aid of the fuel-air mixture jetted through the nozzle 13, a secondary fuel region is formed on the outer periphery of the first combustion region, and the heat transferring from the first combustion region and oxygen contained in the fuel-air mixture accelerate the thermal decomposition reaction of the pulverized coal in this region, which results in producing a reducing thermal decomposition product.
NARATO KIYOSHI
ARASHI NORIO
INADA TOORU
SOUMA KENICHI
OOTSUKA KEIZOU
HISHINUMA TAKAO
BABCOCK HITACHI KK
| JPS54102629A | 1979-08-13 |
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