AIR NOZZLE ARRANGEMENT IN A FLUIDIZED BED BOILER, GRATE FOR A FLUIDIZED BED BOILER, AND A FLUIDIZED BED BOILER

摘要

An air nozzle arrangement (400) for a fluidized bed boiler (100), comprising an air feed pipe (410) and an air nozzle (420) which limit an air feed duct (430) configured to supply air to the furnace (106) of the fluidized bed boiler (100). The air nozzle arrangement (400) comprises a surface (450) configured to guide coarse material along said surface (450). At least part of said surface (450) is thermally insulated from the air nozzle (420) and/or the air feed pipe (410). Furthermore, at least part of said surface (450) is configured to protect at least part of said air nozzle (420) and/or air feed pipe (410). Thus, the temperature of said surface (450) is configured to be high when the fluidized bed boiler (100) is in operation, whereby the solidification of molten material of the fluidized bed in the air nozzle arrangement (400) is reduced.