The invention relates to a plant and to a method for chemical looping oxidation-reduction combustion of a gaseous hydrocarbon feed, for example natural gas essentially containing methane. According to the invention, catalytic pre-reforming of the feed is performed in a pre-reforming zone comprising a fixed reforming catalyst, while benefiting from a heat transfer between the reduction or oxidation zone of the chemical loop and the pre-reforming zone adjoining the reduction or oxidation zone. Pre-reforming zone (130) and oxidation zone (110) or pre-reforming zone (130) and reduction zone (120) are thus thermally integrated within the same reactor (100) while being separated by at least one thermally conductive separation wall (140).

The invention relates to a plant and to a method for chemical looping oxidation-reduction combustion of a gaseous hydrocarbon feed, for example natural gas essentially containing methane. According to the invention, catalytic pre-reforming of the feed is performed in a pre-reforming zone comprising a fixed reforming catalyst, while benefiting from a heat transfer between the reduction or oxidation zone of the chemical loop and the pre-reforming zone adjoining the reduction or oxidation zone. Pre-reforming zone (130) and oxidation zone (110) or pre-reforming zone (130) and reduction zone (120) are thus thermally integrated within the same reactor (100) while being separated by at least one thermally conductive separation wall (140).

The invention relates to a method and to a plant for chemical looping oxidation-reduction combustion (CLC) of a gaseous hydrocarbon feed, for example natural gas essentially containing methane. According to the invention, catalytic reforming of the feed is performed within the reduction zone where combustion of the feed is conducted on contact with an oxidation-reduction active mass in form of particles. The reforming catalyst comes in form of untransported fluidized particles within the reduction zone. The catalyst thus confined in the reduction zone does not circulate in the CLC loop.

The invention relates to a method and to a plant for chemical looping oxidation-reduction combustion (CLC) of a gaseous hydrocarbon feed, for example natural gas essentially containing methane. According to the invention, catalytic reforming of the feed is performed within the reduction zone where combustion of the feed is conducted on contact with an oxidation-reduction active mass in form of particles. The reforming catalyst comes in form of untransported fluidized particles within the reduction zone. The catalyst thus confined in the reduction zone does not circulate in the CLC 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.

Disclosed herein are a fluid sand falling type circulating fluidized bed boiler with a plurality of risers for preventing erosion and corrosion of water tubes and increasing combustion efficiency, and a method of operating the same. The fluid sand falling type circulating fluidized bed boiler with a plurality of risers includes a boiler section into which fuel and oxidizer are injected, a riser section connected to the boiler section so that the fuel and fluid sand supplied from the boiler section are introduced from the bottom of the riser section and flow up, and a relay section provided on the boiler section to supply the fluid sand having passed through the riser section to the boiler section, wherein the fuel is injected from the top of the boiler section and burned while flowing down therein.

Disclosed herein are a fluid sand falling type circulating fluidized bed boiler with a plurality of risers for preventing erosion and corrosion of water tubes and increasing combustion efficiency, and a method of operating the same. The fluid sand falling type circulating fluidized bed boiler with a plurality of risers includes a boiler section into which fuel and oxidizer are injected, a riser section connected to the boiler section so that the fuel and fluid sand supplied from the boiler section are introduced from the bottom of the riser section and flow up, and a relay section provided on the boiler section to supply the fluid sand having passed through the riser section to the boiler section, wherein the fuel is injected from the top of the boiler section and burned while flowing down therein.

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.