| 摘要 |
PURPOSE:To greatly reduce the generation of NOx by shaping a gas nozzle properly and setting the gas ejection speed in a proper range and at the same time providing a flange at the end of the gas nozzle, in a radiant tube burner. CONSTITUTION:Fuel is ejected in the axial and radial directions by means of gas nozzle 3, primary combustion is operated in inner cylinder 5, and secondary combustion is operated by the reaction of the fuel with secondary air flowing out of inner cylinder 5. At this time, when the fuel ejection speed is reduced, NOx is reduced. This effect is increased further when a multi-nozzle is used. Hence, the fuel ejection speed is set within the range of 15-40Nm/sec, and multi-nozzle is formed consisting, for example, of 4 holes on the circumference and 1 hole at the tip. Further, flange 9 is provided at the of gas nozzle 3. By this, a part of primary air is shut off, the fuel and primary air are prevented from being mixed rapidly, and the generation of NOx is checked. |
