| 摘要 |
PURPOSE:To enable sharp reduction of production of nitrogen oxide at each burner, by a method wherein nozzle groups different in an injection direction are formed in a nozzle tip, and a mixing ratio of air to fuel injected through each group is varied. CONSTITUTION:A steam flow 12 flows through the central part of a nozzle tip 2 to each fuel injection nozzle, a fuel flow 13 is fed through a fuel groove 7, and is fed through an outer spray fuel hole 17, a middle spray hole 18, and an inner spray hole 19 to an outer injection nozzle 8, a middle injection nozzle 10, and an inner injection nozzle 11, respectively. The fuel is sprayed at injectin angles different from each other to form outer spray 14, a middle spray 15, and an inner spray 16. The air for combustion is fed from periphery of a nozzle body, and thereby the outer spray 14 is fed to a combustion air excess region to be excellently burnt to form a high temperature flame and bear a thermal load. The fuel, sprayed through the middle injection nozzle 15 and the inner injection nozzle 16, is evaporated and a part thereof is burnt. But, the fuel is brought into a state in that the air for combustion is in short supply, and thereby the fuel forms a reduction flame serving to reduce NOx. This enables reduction of nitrogen oxide at each combustion device, resulting in the possibility to sharply reduce production of nitrogen oxide. |
