Power plant with combustion of a fuel in a fluidized bed

A power plant with combustion of a fuel, primarily coal, at a pressure exceeding the atmospheric pressure in a fluidized bed of particulate material, comprising:

• a combustor enclosed in a pressure vessel and surrounded by compressed combustion air in a space between the combustor and the pressure vessel,
• a plurality of parallel air distributing tubes with nozzles which form as bed bottom and divide the combustor into an upper part which includes a combustion space and a freeboard above the fluidized bed, and a lower part which forms at least two ash chambers for the discharge of ashes and consumed bed material,
• gaps between the air distributing tubes, through which ashes and bed material may pass from the combustion space to the ash chambers,
• a duct located below the bed bottom and between the ash chambers from which the air distributing tubes are supplied with combustion air from the space between the combustor and the pressure vessel for fluidization of the bed and combustion of the fuel in the bed, and
• wherein at least one of the ash chambers is enclosed within a space which is delimited from the space for compressed combustion air in the pressure vessel.