The specialized coal slurry dryer has the characteristics of low energy consumption and high efficiency.

Working principle of coal slurry dryer:

The coal slurry dryer can complete unit operations such as drying, cooling, heating, sterilization, reaction, and low-temperature combustion. The special wedge-shaped stirring heat transfer blade in the equipment has high heat transfer efficiency and self-cleaning function of the heat transfer surface. Wedge shaped hollow blades are densely arranged on the hollow shaft, and the heat medium flows through the blades through the hollow shaft. The heat transfer area within a unit effective volume is large, and the temperature of the heat medium ranges from 40-320 degrees. It can be steam or liquid, such as hot water, heat transfer oil, etc. Indirect conduction heating does not carry away heat with air, and the heat is used to heat the material. The heat loss is only the dissipation of heat to the environment through the insulation layer. The wedge-shaped blade heat transfer surface has self-cleaning function. The relative motion between material particles and the wedge-shaped surface produces a washing effect, which can wash away the materials attached to the wedge-shaped surface and maintain a clean heat transfer surface during operation. The shell of the blade dryer is Ω - shaped, and generally two to four hollow mixing shafts are arranged inside the shell. The shell has a sealed end and an upper cover to prevent material dust leakage and fully exert its function. The heat transfer medium flows through the shell jacket and hollow stirring shaft through the rotary joint. The hollow stirring shaft has different internal structures according to the type of heat medium to ensure good heat transfer effect.

Drying value of coal slurry:

With the continuous development of industrial technology in our country, the remaining coal slurry has been well utilized for secondary purposes. The coal slurry dryer adopts a new technology of crushing and dispersing coal slurry before thermal drying, which enables continuous, industrialized, and automated treatment of coal slurry. After the coal slurry drying process, the moisture content of the coal slurry can be reduced from 25% to 28% to around 12%. Due to the introduction of pre crushing, dispersing, dispersing, and anti sticking processes in the coal slurry drying process, the drying efficiency of coal slurry has been greatly improved, bringing new vitality to the coal slurry drying industry. The dried coal slurry can be mainly used in the following aspects:;

1. As a raw material for processing coal slurry coal for industrial boilers or residential use;  

2. As a fuel for the power plant casting industry, improving fuel utilization efficiency, reducing production costs, and increasing economic benefits;

3. As an additive in brick factories, it improves the hardness and compressive strength of bricks;

4. As an additive in cement plants, it improves the performance of cement;

5. Coal slurry containing certain specific components can be used as chemical raw materials.

Definition of coal slurry:

Coal slurry generally refers to the semi-solid material formed by the moisture content of coal powder, which is a product in the coal production process. Depending on the variety and formation mechanism, its properties vary greatly, and its usability also varies greatly. It has a wide variety of types and applications.

There are roughly the following types:;    The flotation tailings from coking coal beneficiation plants, coal slurry produced from coal water mixtures, coal slurry carried by mine drainage, and coal slurry washed down from gangue hills by watering.

Characteristics of coal slurry:

1. Fine particle size and high particle content, especially particles smaller than 200 mesh account for about 70% to 90%     

2. Strong water holding capacity and high moisture content. The coal slurry dehydrated by the disc vacuum filter generally has a water content of over 30%; The coal slurry dehydrated by the folding belt filter has a moisture content of 26% to 29%; The coal slurry dehydrated by the filter press has a water content of 20% to 24%  

3. High ash content and low calorific value. According to the ash content and calorific value, coal slurry can be divided into three categories: low ash coal mud ash is divided into 20% to 32%, with a calorific value of 12.5-20MJ/kg; Medium ash coal mud ash is divided into 30% to 55%, with a calorific value of 8.4-12.5MJ/kg; High ash coal slurry with ash content>55% and calorific value of 3.5-6.3 MJ/kg;

4. High viscosity. Due to the high content of clay minerals and fine particle size composition in coal slurry, most coal slurry has high viscosity and some even have certain fluidity. Due to these characteristics, the stacking, storage, and transportation of coal slurry are relatively difficult. Especially when stored, its shape is extremely unstable, it will be lost when it comes into contact with water, and it will fly when dried. The result not only wastes valuable coal resources, but also causes serious environmental pollution, sometimes even restricting the normal production of coal washing plants, becoming a more difficult problem for coal preparation plants.

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