Air distribution and slag cooling device and method for fluidized bed gasifier

Abstract

An air distribution cooling slag device and method for a fluidized bed gasification furnace, the air distribution cooling slag device is a part of the fluidized bed gasification furnace, and is arranged below the hearth of the gasification furnace; wherein the air distribution cooling slag device Including: the air distribution section, which is connected with the gasifier furnace; the air distribution section distributes air in stages along the vertical direction, and is used to form the differential speed zone of the air distribution section; the throat, which is set under the air distribution section, is used to form the throat high speed area; the air distribution cooling section is set below the throat; among them, the air distribution cooling section is fed with saturated water vapor, and the pulverized coal passes through the air distribution section and the throat to form bottom slag, and the bottom slag moves in the air distribution cooling section The bed moves down, and the saturated water vapor and the bottom slag exchange heat in countercurrent to realize the air distribution and cooling of the slag in the fluidized bed gasifier. The air distribution and slag cooling device of the present invention combines the functions of air distribution and slag cooling, uses saturated water vapor as the main medium for bottom slag cooling, and adopts a direct heat exchange method to improve heat transfer efficiency.

Description

technical field [0001] The invention relates to the technical field of hydrocarbon fuel energy chemical industry, in particular, the invention relates to an air distribution and slag cooling device and method for a fluidized bed gasifier. Background technique [0002] Coal gasification is one of the core technologies for clean and efficient utilization of coal, and it is the basis for the development of coal chemical process industries such as coal-based chemicals, coal-based clean fuels, industrial gas and polygeneration systems. The fluidized bed gasifier uses 0-10mm pulverized coal as the raw material, the gasification agent and the pulverized coal undergo gasification reaction in a fluidized form, and solid slag is discharged. The fluidized bed gasifier has the advantages of strong adaptability to coal types, no tar in the gas, and high gasification intensity. [0003] At present, the slag cooling method of the fluidized bed gasifier generally adopts indirect heat excha...

AI Technical Summary

Problems solved by technology

The slag cooler in the form of moving bed serpentine heat exchange tubes has a very large volume due to the small heat transfer coefficient between the heat exchange tubes and slag, and between slag and slag, which increases the construction of the fluidized bed gasifier cost, and the internal structure of the slag cooler is very complicated, which is not conducive to later maintenance

[0004] In addition, the backmixing at the bottom of the traditional fluidized bed gasifier is serious, and a large amount of fine materials with high carbon content returned by the feeder will be discharged out of the system with the slag before it can react in the future, resulting in high carbon content in the bottom slag

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