| 摘要 |
PURPOSE:To contrive the self recirculation of exhaust gas and reduce NOx by a method wherein two sets of passages are formed by a partitioning plate and a heat accumulating body is provided at the downstream side of rear wall of an exhaust gas choking unit, common for both passages, while a flame keeper unit and a U-turn unit are provided at the downstream side of the heat accumulating body and a gas nozzle is arranged on the heat accumulating body. CONSTITUTION:An air switching valve 2 is installed at one side of passages A, B defined by a partitioning plate 1 while a choking unit 3, used also for an exhausting unit, is installed at the downstream side of the switching valve 2. The rear wall 4 of the choking unit 3 is projected into both passages A, B and a heat accumulating body 5 as well as a flame keeping unit 6 are provided sequentially in the downstream side of the rear wall 4 while both passages A, B are communicated through a U-turn unit provided at the downstream side of the flame keeping unit 6. A pilot burner 10 is provided on the partitioning plate 1 while a gas nozzle 11 is provided at the rear position of the heat accumulating body 5. A negative pressure unit 8 is formed near the downstream side of rear wall 4 at the passage side opened by the switching valve 2 to suck a part of exhaust gas conducted through the other passage side and restrain the generation of NOx upon combustion. |
