초록 ▼

The invention relates to a fluidized-bed device (F1, F2) provided with a hearth (1, 23) equipped with gas mixture feeds called primary feeds, said gas mixture being enriched with oxygen, and said hearth (1, 23) being provided with a network of two types of primary feed nozzle, a first type of nozzle

The invention relates to a fluidized-bed device (F1, F2) provided with a hearth (1, 23) equipped with gas mixture feeds called primary feeds, said gas mixture being enriched with oxygen, and said hearth (1, 23) being provided with a network of two types of primary feed nozzle, a first type of nozzle (B1, B′1) injecting a first gas mixture at a first level close to the hearth (1, 23) and a second type of nozzle (B2, B′2) injecting a second oxygen-enriched gas mixture at a second level above the first level. According to the invention, said second type of nozzle (B2, B′2) consists of a device for mixing oxygen with a second gas component and connected by its lower end to an oxygen feed (11A, 11A′) and to a feed of second gas component, and of a device for injecting this mixture into the combustion chamber.

대표청구항 ▼

The invention claimed is: 1. In a fluidized-bed device including a combustion chamber and a hearth equipped with primary gas feeds wherein the gas mixture is enriched with oxygen, the improvement comprising: a first type of nozzle through which a first gas mixture is injected at a first level locat

The invention claimed is: 1. In a fluidized-bed device including a combustion chamber and a hearth equipped with primary gas feeds wherein the gas mixture is enriched with oxygen, the improvement comprising: a first type of nozzle through which a first gas mixture is injected at a first level located close to the hearth; and a second type of nozzle through which an oxygen-enriched second gas mixture is injected at a second level located above the first level that is located close to the hearth, the second type of nozzle including a first device for mixing oxygen with a second gas component and a second device for injecting the mixture of oxygen and the second gas component into the combustion chamber of the fluidized-bed device, and the first device having a lower end connected to an oxygen feed and to a feed of a second gas component. 2. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the first gas mixture and the oxygen-enriched second gas mixture are different. 3. In the fluidized-bed device, the improvement as claimed in claim 1 further comprising at least one secondary oxidizer feed through which an oxygen-enriched mixture is injected. 4. In the fluidized-bed device, the improvement as claimed in claim 3 wherein the at least one secondary oxidizer feed comprises a nozzle consisting of a double concentric tube that includes an inner tube and an outer tube, and wherein the oxygen-enriched mixture is injected into the inner tube of the double concentric tube and the first gas mixture is injected into the outer tube of the double concentric tube. 5. In the fluidized-bed device, the improvement as claimed in claim 4 wherein the oxygen-enriched mixture contains 21% to 100% of oxygen. 6. In the fluidized-bed device, the improvement as claimed in claim 4 wherein the oxygen-enriched mixture comprises a second gas component consisting of carbon dioxide, and wherein the first gas mixture consists of carbon dioxide. 7. In the fluidized-bed device, the improvement as claimed in claim 4 wherein the oxygen-enriched mixture comprises a second gas component consisting of nitrogen, and wherein the first gas mixture consists of carbon dioxide. 8. In the fluidized-bed device, the improvement as claimed in claim 4 wherein the oxygen-enriched mixture consists of oxygen-enriched air, and wherein the first gas mixture consists of air. 9. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the first device for mixing oxygen with a second gas component comprises two substantially vertical concentric tubes and wherein the outer tube of the two substantially vertical concentric tubes has an upper end and a side wall and the upper end thereof is closed and orifices are provided in the side wall thereof. 10. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the second device for injecting the mixture of oxygen and the second gas component into the combustion chamber of the fluidized-bed device has an upper part, and wherein the second device for injecting the mixture of oxygen and the second gas component into the combustion chamber of the fluidized-bed device is covered with a cap and orifices are provided in the upper part thereof. 11. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the second type of nozzle comprises two substantially vertical concentric tubes and wherein the outer tube of the two substantially vertical concentric tubes has a side wall and orifices are provided in the side wall thereof. 12. In the fluidized-bed device, the improvement as claimed in claim 11 wherein the two substantially vertical concentric tubes have an upper part and wherein the two substantially vertical concentric tubes are covered with a cap and orifices are provided in the upper part thereof. 13. In the fluidized-bed device, the improvement as claimed in claim 12 wherein the cap is provided with an internal wall in the form of a baffle. 14. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the oxygen feed is provided from a manifold to which the lower end of the first device is connected. 15. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the feed of the second gas component is provided through a direct connection of the lower end of the first device to a windbox filled with the second gas. 16. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the feed of the second gas component is provided from a manifold to which the lower end of the first device is connected. 17. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the oxygen-enriched mixture contains at least one selected from water vapor and sulfur dioxide. 18. In the fluidized-bed device, the improvement as claimed in claim 1 wherein the fluidized-bed device comprises a circulating fluidized-bed boiler. 19. In the fluidized-bed device, the improvement as claimed in claim 18 further comprising a dense fluidized bed of particles operatively connected by a return line to the circulating fluidized-bed boiler wherein the dense fluidized bed of particles includes a heat exchanger and receives solids from the outlet of a cyclone, and wherein the dense fluidized bed of particles further includes at least one secondary feed for injecting an oxygen-enriched mixture into the return line that operatively connects the dense fluidized bed of particles to the circulating fluidized-bed boiler. 20. In the fluidized-bed device, the improvement as claimed in claim 19 wherein the dense fluidized bed of particles is fluidized by a fluidizing gas that is cooled in the heat exchanger before being released to the atmosphere. 21. In the fluidized-bed device, the improvement as claimed in claim 20 wherein the particles of the dense fluidized bed are separated from the fluidizing gas before being injected into the combustion chamber of the fluidizing-bed device. 22. In the fluidized-bed device, the improvement as claimed in claim 21 wherein the particles of the dense fluidized bed are separated from the fluidizing gas by a siphon. 23. In the fluidized-bed device, the improvement as claimed in claim 22 wherein the siphon that is operative to separate the particles of the dense fluidized bed from the fluidizing gas is fluidized by a gas mixture composed of oxygen and carbon dioxide. 24. In the fluidized-bed device, the improvement as claimed in claim 18 further comprising a dense fluidized bed of particles associated with the circulating fluidized-bed boiler and wherein the dense fluidized bed of particles includes at least one secondary feed for injecting an oxygen-enriched mixture above the dense fluidized bed of particles. 25. In the fluidized-bed device, the improvement as claimed in claim 24 wherein the dense fluidized bed of particles is operatively connected by a return line to the circulating fluidized-bed boiler, and the dense fluidized bed of particles further includes at least one secondary feed for injecting an oxygen-enriched mixture into the return line that operatively connects the dense fluidized bed of particles to the circulating fluidized-bed boiler. 26. In the fluidized-bed device, the improvement as claimed in claim 25 wherein the dense fluidized bed of particles is fluidized by at least one selected from air and a component of air. 27. In the fluidized-bed device, the improvement as claimed in claim 25 wherein the dense fluidized bed of particles is fluidized by nitrogen supplied from a cryogenic air separation unit.