Methods and systems of reducing viscosity of gasification system slag
View Patent ↗Methods and systems for gasifier fines recycling system are provided. The system includes a gasifier slag removal system configured to separate first fines from a particulate slag removed from a gasifier by at least one of settling and filtering, a second fines handling system configured to receive second fines from a source other than the gasifier, and an injection system configured to mix the first fines and the second fines and a fuel for injection into the gasifier.
1. A method of combusting a fuel in a gasifier comprising:
providing a fuel to the gasifier;
recovering first fines and a first slag from the gasifier in a water-filled trough coupled in flow communication with the gasifier, wherein combustion of the fuel and the first fines would generate a sludge having a first viscosity;
separating the first fines from the first slag by removing the first slag from the water-filled trough using at least one conveyor and by forcing the first fines out of the water-filled trough using a conveying pump;
providing second fines recovered from a source other than the gasifier;
mixing the first fines, the second fines and the fuel to generate a fuel mixture wherein combustion of the fuel mixture in the gasifier generates a second slag having a second viscosity, the second viscosity being less than the first viscosity; and
combusting the fuel mixture in the gasifier.
2. A method in accordance with claim 1 wherein providing a fuel to the gasifier comprises providing a fuel comprising at least one of Nickel and Vanadium to the gasifier.
3. A method in accordance with claim 1 wherein providing second fines comprises providing second fines comprising flyash.
4. A method in accordance with claim 1 wherein mixing the first fines, the second fines, and the fuel comprises mixing the first fines and the second fines in a relative proportion that facilitates reducing the viscosity of the second slag generated when the fuel mixture is combusted in the gasifier.
5. A method in accordance with claim 1 wherein mixing the first fines, the second fines, and the fuel comprises mixing the first fines and the second fines in a recycle tank configured to receive the first fines and to receive the second fines.
6. A method in accordance with claim 1 A method in accordance with claim 5 wherein mixing the first fines, the second fines, and the fuel comprises mixing the first fines and the second fines in a recycle tank configured to receive a first slurry comprising the first fines and to receive a second slurry comprising the second fines.
7. A method in accordance with claim 1 wherein mixing the first fines, the second fines and the fuel comprises mixing the first fines and the second fines in a recycle tank configured to receive the first fines and to receive the second fines in relative proportion to generate a mixture having a predetermined viscosity slag when the mixture is combusted in the gasifier.
8. A method in accordance with claim 1 wherein mixing the first fines, the second fines, and the fuel comprises pumping a fines mixture including the first fines and the second fines from the recycle tank to the gasifier.