| 摘要 |
PURPOSE:To decrease the produced amount of NOx and unburnt rate of exhaust gas, by turning the swirling direction of the secondary air of each burner to the opposite direction at every adjoining burner, as well as to specify the ratio of coal/quantity of the primary air, in case that coal is burnt using a multistage burner equipment. CONSTITUTION:Finely pulverized coal and the primary air are injected into a furnace from a furnace wall, passong through a nozzle 1 and a tube body 2, respectively, being mixed and burnt with the secondary and the tertiary airs in the form of swirling flows, fed from a sleeve 4 and a port 5, forming the primary and the secondary combustion zones 7 and 8. In this case, NOx can be decreased by setting the ratio of coal/quantity of the primary air within the range of 0.65-1.0. Besides, the unburnt rate of gas can be decreased by increasing the relative speed of the air to pulverized particles in the secondary combustion zone 8, by swirling the secondary and the tertialy airs so as to flow to the opposite directions to each other, by reversely opening the secondary vane 9 and the tertiary resistor 10 at every adjoining burner. |
