| 摘要 |
<p>PURPOSE:To prevent unstable combustion caused by an eccentric flow of combustion gas in an aft-and-fro direction of a boiler by a method wherein a recirculation gas feeding system for each of a front side of the boiler and a rear side of the boiler is provided with a device capable of adjusting an amount of recirculation gas to be fed into a furnace. CONSTITUTION:In case that burners 2 at a front side and a rear side of a boiler at the lower most stage of a furnace 1 are ignited, a degree of opening of a damper for an adjuster 10 for adjusting an amount of recirculation gas at the front side of the boiler is made slightly large and a degree of opening of the damper for a device 12 for adjusting an amount of recirculation gas at the rear side of the boiler is made slightly small. This is branched into a recirculation gas line 9 at the front side of the boiler at the downstream side of the recirculation gas amount adjusting device 8 and a recirculation gas line 11 at the rear side of the boiler. If burner 2 at the front side (or rear side) is diminished and burner 2 at the rear side (or front side of the boiler) is ignited, a degree of opening of the damper of the adjusting device 10 (or 12) is fully closed and a degree of opening of the damper for the adjuster device 12 (or 10) is made large. With this arrangement, a strength of gas flow at the bottom part of the furnace 1 is substantially equal at the front side of the boiler and the rear side of the boiler and it is possible to prevent a circulation flow of the combustion gas from being occurred.</p> |
