The Role Of Coal Crushing Plant In Modern Coal Chemical Industry
Introduction
In the modern coal chemical industry chain, coal, as the core raw material, its pretreatment stage directly determines the efficiency and economy of the subsequent gasification, liquefaction and deep processing processes. An efficient coal crushing and screening plant is not only the guarantee for particle size control, but also the foundation for the project to achieve large-scale, continuous and intelligent production. From open-pit coal mines to power plants at the pit mouth, from coal washing plants to coal chemical industrial parks, it undertakes the key task of converting raw coal into particle size products that meet the process requirements.
The core equipment composition of the crushing station
Modern coal chemical crushing stations are typically composed of four core modules: feeding equipment, conveying equipment, crushing equipment and screening equipment. These devices work in coordination to form a complete crushing and screening plant system.
Feeding equipment: Apron Feeder
The Apron Feeder is responsible for evenly and continuously conveying raw coal from the silo to the downstream crushing equipment. It is usually divided into three series: heavy, medium and light.
The heavy-duty Apron Feeder is particularly suitable for scenarios where there is significant pressure in the silo. It can withstand the direct impact of large pieces of material. With a sealed chain disk design, it optimizes its performance in extremely heavy-load environments and effectively prevents dust from spilling out, meeting the strict environmental protection and occupational health requirements of coal chemical projects. In the EXCT Xinjiang 4,500t /h open-pit coal mine crushing station project, the heavy-duty Apron Feeder was used in conjunction with Mineral Sizer, successfully solving the feeding problem of large pieces of raw coal and ensuring the continuous and stable operation of the system.
Conveyor equipment: Belt Conveyor
Belt Conveyor connects the material transmission of each process link in crushing and screening plant, adopts continuous transportation mode, has traction components, is suitable for horizontal and inclined transportation, and can also be arranged in combination of convex arc, concave arc section and straight section according to the site conditions.
In coal chemical applications, the belt width selection range of belt conveyors is usually from 450mm to 1400mm, and the belt speed can be adjusted according to the load capacity. EP conveyor belts are particularly suitable for medium and long-distance conveying scenarios due to their excellent wear resistance and tensile strength.
In the integrated application of crushing stations, Belt Conveyor serves three functions: first, it connects the material transfer between the feeding equipment and the crusher; second, it links the crusher with the screening equipment; and third, it is a component of mobile crushing equipment to enable flexible relocation operations.
Crushing equipment: Mineral Sizer
Mineral Sizer is the core crushing equipment of the crushing station, and its technical performance directly determines the processing capacity of the entire system. Depending on the model, the maximum feed particle size can reach 1800mm, and the processing capacity can be as high as 20,000 t/h. It can handle both primary and secondary crushing operations and is widely used in coal mines, power plants, coal washing plants and metallurgy industries.
Compared with traditional crushers, mineral sizer has the advantages of high processing capacity, low operating costs, simple structure and long spare parts replacement cycle.
Screening equipment: Roller Screen
The role of Roller Screen in the crushing process is reflected：
One is to conduct pre-screening before secondary crushing, and directly bypass the materials that have already met the particle size requirements to reduce excessive crushing
The second is to separate fine materials after the third-stage crushing to prevent particle size degradation in the subsequent fine crushing stage.
Thirdly, by restricting the excessive crushing of 50mm particle size coal in subsequent processes, the coal quality characteristics are protected and the chemical conversion efficiency is improved.
Roller Screen overcomes the shortcomings of traditional screening equipment such as low processing capacity, easy clogging and insufficient screening efficiency. It has the advantages of low equipment height, no vibration during operation and compact space requirements. Compared with vibrating screens, it can significantly reduce the size of the equipment foundation and is particularly suitable for coal chemical projects with limited sites.
Comprehensive Guide to Equipment Selection
The principle of material property matching
In the initial design stage of crushing and screening plant, a comprehensive analysis of the physical properties of the material must be conducted, including parameters such as the temperature, moisture content, mud content and bulk density of coal. For hard rock materials with a maximum compressive strength of up to 350MPa, crushing equipment with high shear torque capacity should be selected. For damp and sticky materials, special attention should be paid to the anti-adhesion design of the equipment and the processing capacity reduction coefficient to avoid material blockage and reduced production capacity.
Production capacity matching strategy
Take belt conveyors as an example. Their conveying capacity should be calculated based on the characteristics of bulk materials ranging from 5,000 to 25,000 kg per cubic meter. Specific parameters should be referred to the product manual or technical samples provided by the equipment manufacturer. For Mineral Sizer, in addition to focusing on the maximum feed particle size and processing capacity, the crushing ratio is also a key indicator. It is necessary to ensure that the product particle size meets the feed requirements of downstream gasifiers or liquefaction units.
Key indicators for the selection of each equipment
The selection core of Apron Feeder lies in three parameters: material density, maximum block size and silo pressure, based on which the classification selection of heavy, medium and light is carried out.
Belt Conveyor needs to focus on conveying distance, belt width, belt speed and belt strength grade. EP Conveyor belts perform well in medium and long distance applications.
When selecting a Mineral Sizer, it is necessary to verify whether the maximum feed particle size (up to 1800mm) and processing capacity (up to 20,000 t/h) match the project requirements.
For the Roller Screen, attention should be paid to the feed particle size (usually no more than 500mm), the size of the sieve holes and the screening efficiency. The installation inclination Angle is generally controlled between 12 degrees and 15 degrees to balance the processing capacity and screening accuracy.
Conclusion
Under the background of the rapid development of the modern coal chemical industry, crushing and screening plant, as the core equipment for coal pretreatment, its technical level is directly related to the economic benefits and environmental performance of the entire project. By scientifically selecting key equipment for crushing, screening and conveying, and conducting system integration and layout optimization based on the characteristics of materials, coal chemical enterprises can achieve the production goals of high efficiency, low cost and large processing capacity.
