| 摘要 |
PURPOSE:To restrict the occurrence of NOx and improve a thermal efficiency by a method wherein a part of ignited discharged gas coming out of an induction blower is mixed with air at the inlet side of a enforced blower under a low loaded condition and then fed to a fluidized bed boiler. CONSTITUTION:When a fluidized bed boiler 1 is operated under a low load, a damper 17 is opened with a differential pressure sensor 18 to feed a part of ignited discharged gas out of an induction blower 10 into a duct 16 through a circulation duct 15. Since air sucked from surrounding atmosphere under operation of a blower 3 is fed to the duct 16, the ignited discharged gas and the air are uniformly mixed with each other, passed through an air preheater 4 and then injected out of an air nozzle 6 into a fluidized bed 7. With this arrangement, it is not required to supply more than a required amount of air for keeping combustion and so it is possible to restrict the occurrence of NOx and improve the efficiency of boiler.
|
