Rostaggregat för panna med fluidiserad bädd

摘要

A grate assembly for a fluidized bed boiler is provided. A number of parallel sparge pipes extending substantially in the horizontal direction and are provided with devices for supplying fluidizing air from within sparge pipes into a combustion chamber located above the grate assembly. The discharge of coarse material is effected through an aperture system between the sparge pipes into a receiver unit fitted below the grate assembly. At least some of the sparge pipes are provided with a cool medium circulation, wherein at least a part of the cool medium circulation is placed in the sparge pipes at the upper edges thereof, to extend so that it provides a limit to the edge of the aperture system in the upper part of the sparge pipe in the longitudinal direction of the sparge pipe. Devices for supplying fluidizing air comprise a tubular supply channel that is directed from the upper surface of the sparge pipe. The supply channel is provided with air nozzle apertures at its upper part. The supply channel for at least some of the devices for supplying fluidizing air is fitted in vertical direction to extend on top of a part of the cool medium circulation in a vertical direction.