A lignite drying and upgrading system

Abstract

The invention relates to a lignite drying and upgrading system, which includes four silos with heat exchange function and a heat exchange device that can provide heat exchange medium to the four silos for heat exchange; the four silos have medium inlets and Medium outlet, the medium inlet and medium outlet of the four silos are respectively connected to the medium flow switching control pipeline, and the flow of the heat exchange medium in the four silos can be changed by opening or closing the corresponding switching valve on the medium flow switching control pipeline. flow direction, so that the four silos can be switched among the four silo functions of preheating silo, drying silo, upgrading silo, and unloading silo to perform one of the silo functions respectively, and the heat exchange medium is After the compartment is isolated, it flows in the order of upgrading compartment-drying compartment-preheating compartment and returns to the heat exchange device. The invention has the advantages of simple manufacture, low requirements, easy control of the drying and upgrading process, energy circulation, greatly reduced energy consumption, and a sealed structure to ensure safe operation during the drying process, which is beneficial to environmental protection.

Description

technical field [0001] The invention belongs to the technical field of lignite drying and upgrading, and in particular relates to a lignite drying and upgrading system. Background technique [0002] Lignite is a kind of coal with a large content in my country and in the world. It is characterized by a short formation time, low coalification degree, high moisture content, high volatile matter content, easy weathering and spontaneous combustion, and relatively low calorific value such as bituminous coal. Lignite The characteristics of use at this stage are like chicken ribs, and the degree of use is very low. my country's lignite reserves are large, about 200 billion tons or more. With the change of my country's energy structure, the utilization ratio of lignite will be higher and higher in the future. However, according to the characteristics of high moisture content of lignite, direct combustion or blending of boilers will waste a lot of energy, and it is easy to spontaneou...

AI Technical Summary

Problems solved by technology

The disadvantages of this method are: 1. The drum seal is difficult to solve. When the drum is rotating, the seal generated at the dynamic and static junction is not easy to deal with, and the seal of the inlet and outlet also needs to be dealt with; 2. The drum is a dynamic structure, which needs to be sealed. The support of the slewing mechanism requires extremely high mechanical manufacturing requirements for the drum; 3. The drum is a large structure, which is extremely inconvenient to manufacture and transport; 4. Due to the sealing reason, the inside of the drum is easy to enter the air, and the dried lignite is easy to burn and explode

5. The rotating dynamic structure is easy to cause a large amount of dust, which needs to be treated at the end, with a large workload and high consumption

6. The drum structure consumes a lot of heat energy, and the evaporated steam causes waste, etc.

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