Method and system for drying fuels in the form of dust, particularly to be fed to a gasification process

摘要

The procedure for drying dust residue in gasification of fuels e.g. coal and petroleum coke, comprises crushing the fuel in a grinder (2), supplying the fuel to a filter (3) or separator by means of a conveying- and a drying gas, and redirecting a part of the conveying/drying gas in the cycle after heating up into the grinder. A part of the conveying/drying gas flow is cooled and dehumidified in a spraying tower (6). A part of the dried gas of the environment and/or furnace is again supplied to the conveying/drying gas flow. The procedure for drying dust residue in gasification of fuels e.g. coal and petroleum coke, comprises crushing the fuel in a grinder (2), supplying the fuel to a filter (3) or separator by means of a conveying- and a drying gas, and redirecting a part of the conveying/drying gas in the cycle after heating up into the grinder. A part of the conveying/drying gas flow is cooled and dehumidified in a spraying tower (6). A part of the dried gas of the environment and/or furnace is again supplied to the conveying/drying gas flow. The conveying/drying gas flow behind the mixing of the dried gas flow from the spraying tower cooling is supplied to a heat exchanger (11). A partial flow of the condensate resulting in the spraying tower is leadable by means of a bypass (16) around the cycle heat exchanger for temperature control of the conveying/drying gas flow. The temperature of the gas flow over a further heat exchanger intended in the main circulation of the conveying/drying gas flow, is adjusted to the temperature of the gas flow reconducted to the spraying tower. A cleaning and/or a pressure rising device is intended to the gas flow for output to the environment/furnace. The temperature of the conveying/drying gas flow is raised before entrance into the grinder over a burner. An inert gas is supplied to the circulation. Over the spraying tower, 15% of the gas flow from the grinder is supplied to the drying process. An independent claim is included for a device for drying dust residue in gasification of fuels.