A brown coal dryer is a specialized equipment used for drying brown coal, mainly used to evaporate the moisture content of brown coal to below a certain level to ensure its quality and combustion performance. Lignite dryers usually adopt a low-temperature four stage drying process, gradually reducing the moisture content of lignite through heat treatment in different temperature ranges.

The working principle of a brown coal dryer mainly includes the following steps:

First level drying zone: Remove most of the moisture at a high temperature of 400 ℃ to ensure that the chemical composition of lignite does not change and is not easily combustible.

Secondary drying zone: High yield water removal is achieved through medium temperature strong induced draft at 300 ℃ to ensure that lignite does not coking.

Third level drying zone: The temperature is controlled between 120 ℃ and 210 ℃, and the material is repeatedly broken up using the crushing device inside the drum, and then dried downstream.

Fourth level drying zone: The temperature ranges from 60 ℃ to 80 ℃, and residual moisture is removed through a low-temperature hot air flow with negative pressure generated by the induced draft system.

Lignite dryers are widely used in various industries, including:

Coal industry: used for drying coal slurry, raw coal, flotation clean coal, and mixed clean coal.

Building materials industry: used for drying materials such as blast furnace slag, clay, bentonite, limestone, sand, quartz, etc.

Mineral processing industry: used for drying various metal concentrates, waste residues, tailings and other materials.

Chemical industry: used for drying non heat sensitive materials.

The advantages of lignite dryer include:

Easy to operate: The device is easy to operate and maintain.

Low cost: Compared to other drying methods, the operating cost of lignite dryer is lower.

Low energy consumption: It can effectively reduce energy consumption because dried lignite is easier to burn and release heat.