| 摘要 |
PURPOSE:To improve the condition of combustion, reduce a discharging volume of nitrogen oxide and prevent a deposition and accumulation of ash at a bottom part of a furnace by a method wherein a processing of the ash is combined with a bouble stage combustion technology. CONSTITUTION:The first stage combustion zone and the second stage combustion zone of a furnace which are divided in a direction of advancement of combustion gas are arranged in such a way as the second combustion zone is located substantially at the same position as that of the first combustion zone or at a higher position than that of the second stage combustion zone, a mean flow speed of the gas in the first stage combustion zone is made faster than that of the second stage combustion zone or at least made similar to that in the second stage combustion zone and further the flow speed in the first stage combustion zone is made faster than 5m/s. Setting of such a slope of combustion gas flow causes the particles of ash which are apt to be settled to be floated and flowed under an influence of the combustion gas flow, resulting in that the ash may not be settled and then the ash is discharged together with the combustion gas, so that the ash can be separated from gas by a separator and the wasted. With this arrangement, it is possible to keep a discharging of low NOx with a main fuel of oil coke and make a stable heating of boiler for a long period of time without any trouble of settlement of ash. |
