The present invention relates to a fluidized bed gas distribution nozzle with the following features in its functional position: a gas inlet pipe (10), having: an inner surface (10i), an outer surface (10o), a lower end section (10l) adapted to receive gas from an associated gas source, an upper end section (10u), a plurality of openings (12) formed in the upper end section (10u), each opening (12) extending form the inner surface (10i) of the gas inlet pipe (10) to the outer surface (10o) of the gas inlet pipe (10), a gas distribution cap (20) connected or connectable to the gas inlet pipe (10), having: an upper top (20u), a lower bottom (20l) arranged at a vertical distance below said upper top (20u) and surrounding the gas inlet pipe (10), a peripheral wall (20w) having an inner surface (20i) and an outer surface (20o) and extending between said upper top (20u) and said lower bottom (20l), outlets (22) within the peripheral wall (20w) extending from the inner surface (20i) of the peripheral wall (20w) to the outer surface (20o) of the peripheral wall (20w).

The present invention relates to a fluidized bed gas distribution nozzle with the following features in its functional position: a gas inlet pipe (10), having: an inner surface (10i), an outer surface (10o), a lower end section (10l) adapted to receive gas from an associated gas source, an upper end section (10u), a plurality of openings (12) formed in the upper end section (10u), each opening (12) extending form the inner surface (10i) of the gas inlet pipe (10) to the outer surface (10o) of the gas inlet pipe (10), a gas distribution cap (20) connected or connectable to the gas inlet pipe (10), having: an upper top (20u), a lower bottom (20l) arranged at a vertical distance below said upper top (20u) and surrounding the gas inlet pipe (10), a peripheral wall (20w) having an inner surface (20i) and an outer surface (20o) and extending between said upper top (20u) and said lower bottom (20l), outlets (22) within the peripheral wall (20w) extending from the inner surface (20i) of the peripheral wall (20w) to the outer surface (20o) of the peripheral wall (20w).

Provided are a pulverized coal boiler with a bottom combustor, and a control method for the pulverized coal boiler, wherein the pulverized coal boiler includes a furnace, at least one bottom combustor and a secondary air distributing device. Each combustor is provided with a combustor spout, and the secondary air distributing device surrounds the combustor and is arranged at the bottom of the furnace. The secondary air distributing device includes an internal secondary air distributing device and an external secondary air distributing device, wherein the internal secondary air distributing device includes an internal secondary air gathering box and an internal secondary air pipe, and the external secondary air distributing device includes an external secondary air gathering box and an external secondary air pipe.

The present invention relates to a method for operating a fluidized bed apparatus and to a fluidized bed apparatus, the method comprising the following steps: providing particulate metal to a reaction chamber of a fluidized bed reactor, providing an oxidizing agent to a fluidizing bottom of the fluidized bed reactor such that particulate matter comprising the particulate metal is fluidized, wherein the particulate metal reacts with the oxidizing agent to particulate metal oxide, withdrawing particulate metal oxide from the reaction chamber, storing the withdrawn particulate metal oxide, providing particulate metal oxide to the reaction chamber of the fluidized bed reactor, providing a reducing agent containing gas to the fluidizing bottom of the fluidized bed reactor such that particulate matter comprising the particulate metal oxide is fluidized, wherein the particulate metal oxide reacts with the reducing agent to particulate metal, withdrawing the particulate metal from the reaction chamber, storing the withdrawn particulate metal.

The present invention relates to a method for operating a fluidized bed apparatus and to a fluidized bed apparatus, the method comprising the following steps: providing particulate metal to a reaction chamber of a fluidized bed reactor, providing an oxidizing agent to a fluidizing bottom of the fluidized bed reactor such that particulate matter comprising the particulate metal is fluidized, wherein the particulate metal reacts with the oxidizing agent to particulate metal oxide, withdrawing particulate metal oxide from the reaction chamber, storing the withdrawn particulate metal oxide, providing particulate metal oxide to the reaction chamber of the fluidized bed reactor, providing a reducing agent containing gas to the fluidizing bottom of the fluidized bed reactor such that particulate matter comprising the particulate metal oxide is fluidized, wherein the particulate metal oxide reacts with the reducing agent to particulate metal, withdrawing the particulate metal from the reaction chamber, storing the withdrawn particulate metal.

A fluidizing nozzle for introducing fluid into a fluidized bed reactor and a fluidized bed reactor. The fluidizing nozzle includes a nozzle tube limiting at least a part of a feed channel in which fluid is configured to flow, at least one fluid discharge opening arranged near a downstream end of the nozzle tube, and a pot-like hood, which sealingly closes the nozzle tube with a hood cover of the pot-like hood at the downstream end of the nozzle tube at which said at least one fluid discharge opening is provided. The feed channel is provided with a flow restriction element defining at least one flow restriction feed channel upstream of said at least one fluid discharge opening.

A combustor air bar grid for use within a fluidized bed reactor includes at least two main air collector bars in fluid communication with a source of fluidizing gas, a plurality of primary air bars that are transversal to the main air collector bars and arranged on the at least two main air collector bars such that the main air collector bars support them, and in fluid communication to at least two of the main air collector bars. The main air collector bars and the primary air bars define ash removal openings in the air bar grid and a plurality of fluidized nozzles are arranged to each of the primary air bars for fluidizing the bed reactor. A fluidized bed reactor includes such a combustor air bar grid.

A combustor air bar grid for use within a fluidized bed reactor includes at least two main air collector bars in fluid communication with a source of fluidizing gas, a plurality of primary air bars that are transversal to the main air collector bars and arranged on the at least two main air collector bars such that the main air collector bars support them, and in fluid communication to at least two of the main air collector bars. The main air collector bars and the primary air bars define ash removal openings in the air bar grid and a plurality of fluidized nozzles are arranged to each of the primary air bars for fluidizing the bed reactor. A fluidized bed reactor includes such a combustor air bar grid.

A circulating fluidized bed boiler, comprising a furnace, a loopseal, and a loopseal heat exchanger arranged in the loopseal. The loopseal heat exchanger comprises at least an inlet chamber, a bypass chamber, and a first heat exchange chamber, heat exchanger pipes arranged in the first heat exchange chamber, and a primary particle outlet for letting out bed material from the first heat exchange chamber. The primary particle outlet has at least a first part and a second part separated from each other by a barrier element in such a way that the first part of the primary particle outlet has a first height and a first width, wherein a ratio of the first height to the first width is less than 0.5 or more than 2. Use of the circulating fluidized bed boiler such that fluidizing gas and bed material are let out from the first heat exchange chamber via the primary particle outlet.

A circulating fluidized bed boiler, comprising a furnace, a loopseal, and a loopseal heat exchanger arranged in the loopseal. The loopseal heat exchanger comprises at least an inlet chamber, a bypass chamber, and a first heat exchange chamber, heat exchanger pipes arranged in the first heat exchange chamber, and a primary particle outlet for letting out bed material from the first heat exchange chamber. The primary particle outlet has at least a first part and a second part separated from each other by a barrier element in such a way that the first part of the primary particle outlet has a first height and a first width, wherein a ratio of the first height to the first width is less than 0.5 or more than 2. Use of the circulating fluidized bed boiler such that fluidizing gas and bed material are let out from the first heat exchange chamber via the primary particle outlet.