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oxidizing agent to particulate metal oxide, withdrawing particulate metal oxide from the reaction chamber, storing the withdrawn particulate metal oxide, providing particulate metal oxide to the reaction chamber of the fluidized bed reactor, providing a reducing agent containing gas to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with the reducing agent to particulate metal, withdrawing the particulate metal from the reaction chamber, storing the withdrawn particulate metal.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oxidizing agent to particulate metal oxide, withdrawing particulate metal oxide from the reaction chamber, storing the withdrawn particulate metal oxide, providing particulate metal oxide to the reaction chamber of the fluidized bed reactor, providing a reducing agent containing gas to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with the reducing agent to particulate metal, withdrawing the particulate metal from the reaction chamber, storing the withdrawn particulate metal.

The invention relates to an integrated method for thermal conversion and indirect combustion of a heavy hydrocarbon feedstock in a redox chemical loop for producing hydrocarbon streams. The heavy hydrocarbon feedstock (1) is brought into contact with inert particles (2) in a thermal conversion zone (100). Thermal conversion in the absence of hydrogen, water vapour and a catalyst produces a first gaseous effluent of hydrocarbon compounds (4) and coke, which effluent is deposited on the inert particles (5). The latter is then burned in a redox chemical loop (200) in the presence of oxygen-carrying solid particles (6). The inert particles thus flow between the thermal conversion zone (100) and a reduction zone (300) of the chemical loop while the oxygen-carrying solid particles flow between the oxidation (400) and reduction zones (300) of the chemical loop.

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.

A heat exchanger (10) suitable for recovering heat from bed material of a fluidized bed boiler (1). The heat exchanger (10) comprises first and second heat exchanger tubes (810, 820) and first and second feeding chambers (310, 320) configured to supply bed material to the first and second heat exchanger tubes (810, 820), respectively. The first heat exchanger tubes (810) are arranged on a first side of a plane (P) that intersects the first feeding chamber (310) and the second heat exchanger tubes (820) are arranged on a second side of the plane (P). The first feeding chamber (310) is configured to supply bed material to the second feeding chamber (320).

A heat exchanger (10) suitable for recovering heat from bed material of a fluidized bed boiler (1). The heat exchanger (10) comprises first and second heat exchanger tubes (810, 820) and first and second feeding chambers (310, 320) configured to supply bed material to the first and second heat exchanger tubes (810, 820), respectively. The first heat exchanger tubes (810) are arranged on a first side of a plane (P) that intersects the first feeding chamber (310) and the second heat exchanger tubes (820) are arranged on a second side of the plane (P). The first feeding chamber (310) is configured to supply bed material to the second feeding chamber (320).

An apparatus of hydrocarbon fuel reactors separates and purifies carbon dioxide (CO.sub.2). Interconnected fluidized beds are applied in chemical-looping combustion. A multi-stage reduction reaction is processed with iron-based oxygen carriers. Three reduction stages using the iron-based oxygen carriers are accurately and completely controlled. Each of the three stages is separately processed in an individual space. Oxygen in the iron-based oxygen carriers can be fully released. High-purity CO.sub.2 is obtained. Hydrogen can be produced as an option. Horizontal connection of three reduction reactors is changed into vertical one. An oxidation reactor is further connected. Thus, the whole structure occupies less area and effectively uses vertical space. Not only small space is effectively used; but also high-volume capacity is obtained. Each of the reactors has better geometry flexibility. The tandem reactor in each layer has less geometric influence and limitation. Therefore, each of the reactors can be resized on its own.

Fluidized bed heat exchanger with a chamber (24), comprising at least one solid particles inlet port (22) at least one solid particles outlet port (30), arranged at a distance to the at least one inlet port (22), means (46) for introducing a fluidizing gas from a bottom area (24b) of said chamber (24) into said chamber (24), wall-like heat transfer means (28) in its lower part, extending in a main flow direction of the solid particles on their way from the inlet port (22) to the outlet port (30), substantially parallel to each other, with a space (C) between adjacent heat transfer means (28), at least one baffle (50,52) in its upper part, extending substantially perpendicular to the heat transfer means (28), downwardly from a chamber ceiling (24c), with its lower end at a distance to the heat transfer means (28) and comprising extensions (E), protruding into the space (C) between adjacent heat transfer means (28), and couplings (B) to mechanically connect the said heat transfer means (28) to said extensions (E).

Fluidized bed heat exchanger with a chamber (24), comprising at least one solid particles inlet port (22) at least one solid particles outlet port (30), arranged at a distance to the at least one inlet port (22), means (46) for introducing a fluidizing gas from a bottom area (24b) of said chamber (24) into said chamber (24), wall-like heat transfer means (28) in its lower part, extending in a main flow direction of the solid particles on their way from the inlet port (22) to the outlet port (30), substantially parallel to each other, with a space (C) between adjacent heat transfer means (28), at least one baffle (50,52) in its upper part, extending substantially perpendicular to the heat transfer means (28), downwardly from a chamber ceiling (24c), with its lower end at a distance to the heat transfer means (28) and comprising extensions (E), protruding into the space (C) between adjacent heat transfer means (28), and couplings (B) to mechanically connect the said heat transfer means (28) to said extensions (E).