PURPOSE: To prevent the adhesion of combustion ash to a furnace wall across a wide range by a method wherein a part of air stream in an air feeding flow passage is branched to provide an air inducing member for forming wall surface jet stream flowing against a furnace wall around a burner, in a combustion device burning solid fuel such as coal or the like by carrying it to the burner by air.
CONSTITUTION: In a pulverized coal burning boiler, pulverized coal is carried to a burner by air stream. The burner is a tertiary air flow branching type low NOx pulverized coal burner and a primary air flow passage 14 of mixed flow 12 of primary air and pulverized coal is provided at the outer periphery of a starting burner 11 at the center of the burner. A secondary air flow passage 15 and a tertiary air flow passage 16 are provided sequentially around the outer periphery of a bulkhead provided around the outer periphery of the primary air flow passage 14. In this case, tertiary air separators 22a, 22b are provided at the end of the furnace side of the bulkhead for the secondary and tertiary air passages 15, 16 to branch air by a separator 22b and produce wall surface jet stream 19b. The separator 22b is formed by bending toward the outer peripheral side of the burner and is provided with a twisted structure so as to swirl the tertiary air 19.
NOMURA SHINICHIRO
OKIURA KUNIO
OYATSU NORIYUKI
MORITA SHIGEKI
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