Entrained-flow bed gasification system and method for vapour conveyed pulverized coal

Abstract

Entrained-flow bed gasification system and method for a vapour conveyed pulverized coal are disclosed, which belong to the technical field of coal gasification and coal conversion. The gasification system disclosed by the invention is composed of an entrained-flow bed gasification furnace with a water-cooling wall, a pulverized coal issuance tank, an air separation plant, a vapour convey tube and a concentrated-phase pulverized coal convey tube. An entrained-flow bed gasification process of conveying a pulverized coal via the vapour of the system comprises the following steps that: a high-temperature superheat vapour at the outlet of the water-cooling wall is conveyed to the body or the outlet of the pulverized coal issuance tank to heat the pulverized coal, and is used as a carrier gas for carrying the pulverized coal and conveying the pulverized coal into the entrained-flow bed gasification furnace via the concentrated-phase pulverized coal convey tube; the air separation plant provides pure oxygen into the entrained-flow bed gasification furnace; and the pure oxygen, the vapour and the pulverized coal perform a gasification reaction in the entrained-flow bed gasification furnace. In the invention, the waste heat of a gasification reaction is used for generating a high-temperature superheat vapour to realize a preheating for coal and a conveying for a concentrated-phase pulverized coal, so that the oxygen consumption of the present entrained-flow bed gasification furnace can be reduced, and the overall coal gasification efficiency can be increased.

Description

Technical field [0001] The invention relates to a coal gasification system and method, belonging to coal gasification and coal conversion technology. Background technique [0002] Coal gasification technology is a clean coal conversion and utilization technology, as well as an important means to produce industrial synthesis gas, and has important applications in the chemical and energy fields. The entrained bed coal gasification method is currently a relatively advanced gasification method, which has the advantages of large gasification capacity, high carbon conversion rate, and continuous gasification. The characteristic of the entrained-bed gasifier is that the gasification agent and raw coal are injected into the gasifier at high speed at the same time, forming a high-temperature gasification flame under the high-temperature and high-pressure environment in the furnace. The pulverized coal or coal slurry is rapidly heated in the gasification flame to quickly complete a series...

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Problems solved by technology

[0005] 2. In the currently commonly used pulverized coal dense phase transportation methods, inert gases are generally used as carrier gases. Since inert gases themselves do not participate in the gasification reaction, their addition will cause a certain amount of heat loss and will also reduce the synthesis gas. purity

[0006] 3. In the dense phase transportation of pulverized coal at room temperature, the moisture in the coal will cause instability in the transportation process, affect the safe operation of the gasifier, and restrict the improvement of the thermal efficiency of the gasifier and the purity of the syngas

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