Moving bed brown coal drying method and device

Abstract

The invention discloses a moving bed brown coal drying method and device, and relates to the technical fields of brown coal drying techniques and devices. Brown coal enters a direct drying chamber of a horizontal moving bed to remove moisture after being dried by an indirect drying chamber of a vertical moving bed firstly; and high-temperature hot air inside the indirect drying chamber indirectly transfers the heat to brown coal particles when flowing through a pipeline arranged in the movement direction of a coal bed. Therefore, a rapid drying process is achieved; the floor space and the height of a drying system can be reduced; and safe operation of the system can be ensured. A direct drying chamber adopts a one-layer or multi-layer horizontal moving bed structure; the hot gas and the brown coal are directly subjected to heat exchange; the moisture content of a terminal dry product is conveniently controlled by controlling the retention time of the brown coal particles; and the adaptability of the drying system on raw coal is more excellent. The entire device does not generate a fluidization control problem; treatment of large-grain brown coal particles is facilitated; the particle sizes of the particles of the terminal product and controllable moisture content are guaranteed; and the system is simpler, more stable and safer to operate.

Description

technical field [0001] The invention relates to a moving bed type lignite drying method, which belongs to the field of high-efficiency coal utilization. Background technique [0002] Lignite reserves account for about 15% of my country's total coal reserves. It is one of my country's main coal resources and plays an important role in my country's power and chemical coal. Lignite is a kind of coal with low degree of coalification in the underground storage period. Its moisture and ash content are relatively high, and the moisture content is mostly 20-50%. Lignite is mainly distributed in Inner Mongolia, Yunnan, Xinjiang and other places. Due to economic development, the coal consumption in these areas is less than that in economically developed areas. Therefore, lignite needs to be transported to a relatively distant utilization site. Due to the presence of high moisture content in lignite, the railway system is extremely wasteful. The lignite drying process can not only...

AI Technical Summary

Problems solved by technology

[0005] Most of the existing lignite drying and upgrading processes are in the scale demonstration stage. Small land occupation, easy control of moisture in terminal dried products, and stable operation are the main reasons that plague the large-scale application of these processes.

Judging from the application of lignite drying technology, there is still a lack of perfect technology and technology in terms of engineering application and economy.

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