| 摘要 |
PURPOSE:To enable secure and stable direct ignition to pulverized coal without generating such thermal NOx as that in a plasma arc method by installing a heater heating a mixture at the downstream of a back fire preventing plate and an ignitor igniting the mixture after heating. CONSTITUTION:The heating value of a heater 5 is so controlled that the generated amount of CH4 satisfies the necessary concentration for ignition with a controller 15 according to the signal from a gas sensor 6 installed at the downstream part of the heater 5. Danger in case when pulverized coal 9 is ignited in the inside of the heater 5 by any chance is prevented and heat loss can be controlled to a minimum by making the heating source for a mixture approach an ignition region as near as possible. Because the mixture of which volatile component is sufficiently vaporized by the heater 5 collides with the heating element 10 for ignition heated at 1000-1200 deg.C and placed at the downstream part of a flame holder 3, the volatile component in the pulverized coal is continuously ignited to form flames. Further those flames propagate and the whole supplied pulverized coal is ignited.
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