METHOD FOR FEEDING AIR TO A FLUIDIZED BED BOILER, A FLUIDIZED BED BOILER AND FUEL FEEDING MEANS FOR A FLUIDIZED BED BOILER

摘要

The invention relates to a method for feeding air to a fluidized bed boiler. The method comprises supplying primary air into the first combustion zone (I) from under the fluidized bed and supplying combustion air for volatile matter into the first combustion zone (I) along with the fuel supply. Part of the combustion air for volatile matter is supplied as a first combustion air supply mixed with the fuel supply and part of the combustion air for volatile matter is supplied as a second combustion air supply surrounding at least part of the fuel supply. The velocity at which the combustion air for volatile matter is supplied in both the first and the second combustion air supplies is 10 to 25 m/s. The invention further relates to a fluidized bed boiler and fuel feeding means.