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.

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 steam reforming of the feed is performed between two successive feed combustion steps on contact with an oxidation-reduction active mass in form of particles. The reforming catalyst is arranged in a fixed bed in an intermediate reforming zone (130) between the two reduction zones (120, 140) where the two combustion steps are conducted.

FIG. 2 to be published.

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 steam reforming of the feed is performed between two successive feed combustion steps on contact with an oxidation-reduction active mass in form of particles. The reforming catalyst is arranged in a fixed bed in an intermediate reforming zone (130) between the two reduction zones (120, 140) where the two combustion steps are conducted.

FIG. 2 to be published.

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.

The present invention relates to a fuel supply device of a circulating fluidized bed boiler. The fuel supply device includes: a feeder transferring fuel; a chute extending downwardly inclined from a lower end portion of the feeder to a combustor, the chute supplying the fuel to the combustor through a fuel injection hole; and a combustion heat blocking part provided at a portion of the fuel injection hole, the combustion heat blocking part preventing the fuel from being melted or burned at an end of the fuel injection hole connected to the combustor and in the fuel injection hole due to back fire. The combustion heat blocking part includes a heat shield plate installed at a sidewall of the combustor at an upper side of the fuel injection hole.

The present invention relates to a fuel supply device of a circulating fluidized bed boiler. The fuel supply device includes: a feeder transferring fuel; a chute extending downwardly inclined from a lower end portion of the feeder to a combustor, the chute supplying the fuel to the combustor through a fuel injection hole; and a combustion heat blocking part provided at a portion of the fuel injection hole, the combustion heat blocking part preventing the fuel from being melted or burned at an end of the fuel injection hole connected to the combustor and in the fuel injection hole due to back fire. The combustion heat blocking part includes a heat shield plate installed at a sidewall of the combustor at an upper side of the fuel injection hole.

The present invention relates to a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system and an operation method thereof, particularly to a chemical looping combustion and carbon dioxide direct reduction (CLC-CDR) integration system including: an air reactor, wherein an oxygen carrier particle is oxidized by reacting with injected air and air from which oxygen was partially removed is discharged; a fuel reactor, wherein the oxidized oxygen carrier particle is supplied, a supplied fuel is reacted to reduce the oxidized oxygen carrier particle, and carbon dioxide including H.sub.2O is discharged; and a carbon dioxide reduction reactor, wherein the reduced oxygen carrier particle is supplied, supplied carbon dioxide is reacted to discharge carbon monoxide, and the reduced oxygen carrier particle is partially oxidized and supplied to the air reactor.