LOW NOx AND LOW CO COMBUSTION DEVICE

摘要

PROBLEM TO BE SOLVED: To restrain the emission of NOx and CO while realizing a high-volume and small size boiler. SOLUTION: A heat transfer tube row of a heat transfer tube wall and the heat transfer tube row in a flowing direction of combustion flame of a heat transfer tube group are zigzag arranged, and the heat transfer tube rows adjacent to each other of the heat transfer tube group are zigzag arranged so that combustion flame of a combustion burner forms combustion flame passages R1, R2, R3, R4 that spirally flow toward a combustion exhaust gas outlet between the heat transfer tube row of the heat transfer tube wall and the heat transfer tube row of the heat transfer tube group and between the heat transfer tube rows adjacent to each other of the heat transfer tube group. Enlarged flame passages at a point where a plurality of flame flow passage join is provided.