The Roller Screen is a specialized screening equipment designed for coal conveying systems. It is mainly used to separate coal gangue, impurities and oversized pieces from raw coal, ensuring the smooth operation of downstream equipment (such as mineral sizer and belt conveyor).
Its core component is a series of parallel screen shafts, which are installed at an inclined angle within the screen frame and driven to rotate by a drive device. Additionally, the surface of the screen shaft is equipped with screen discs, which can enhance the screening accuracy of coal gangue.
Roller Screen Working Principle
- When the coal gangue falls onto the screen surface from the feed inlet, it rolls forward under the rotation of the screen shaft and the force of gravity. The coal blocks smaller than the screen hole gap pass through the screen, while the large pieces of coal gangue are transported to the end and discharged, achieving the separation of coal and large pieces of coal gangue.
- The surface of the screen shaft can be equipped with different types of screen discs according to the characteristics of the materials to achieve the best screening effect. This equipment is ingeniously designed, has a compact structure, and can meet the screening requirements of various complex materials.
Why Use Roller Screen For Screening Coal Gangue?
- With Pre-Screening Function
The roller screen is used to pre-screen the coal before it enters the primary mineral separator, thereby reducing the amount of material entering the primary mineral separator. This not only reduces the unnecessary wear of the primary primary mineral separator but also lowers the size and processing capacity of the required mineral separator.
- Strong Anti-Blocking Performance
The screen shaft can be equipped with triangular,梅花-shaped, or circular disc-shaped screen discs. Moreover, each screen disc of the screen shaft is equipped with a self-cleaning device. During rotation, damp raw coal and mud-coated coal gangue will not adhere and block the sieve holes. Compared with traditional vibrating screens, in the high-humidity working conditions of underground raw coal and washed and selected materials, the probability of screen blockage is significantly reduced. It is very suitable for the screening scenarios of coal with mud and gangue in coal mines.
- Durable And Impact-Resistant
The Disc Screen is entirely made of thickened steel plates, wear-resistant manganese-chromium alloy steel screen discs, and heavy-duty bearing structures. It has excellent wear resistance and can withstand the impact, crushing and friction caused by large pieces of coal gangue falling down. It is unlikely to deform or break and is suitable for the harsh working conditions where raw coal coarse materials fall.
- Smooth And Stable Conveying
The materials slowly roll and move forward on the screening surface. The fine coal fully sinks through the screening gaps. The large coal gangue continuously moves forward above the screening surface. The screening accuracy is stable. It can separate the gangue and also remove the large pieces of gangue in advance, protecting the subsequent mineral separator from being damaged by the large pieces of gangue.
- Adjustable Screening Particle Size
By changing the center distance between adjacent screen shafts and replacing different diameter screen discs, the screening gap can be freely adjusted. Based on the conventional particle sizes of raw coal and coal gangue at the site, the classification size can be set, allowing for precise separation of large pieces of gangue.
- Low Failure Rate
The equipment has no high-frequency vibration structure, with small foundation load and low noise. It can operate continuously for 24 hours. It is suitable for the large-scale raw coal gangue removal and pre-sieving scenarios in coal mines, and the operation and maintenance are simple, making it very suitable for the front-end pre-treatment process of coal mines and coal washing plants.
- Environmental Protection
The fully enclosed structure acts like a sturdy barrier, firmly confining dust pollution within the system, effectively preventing any dust from spilling out. This design is highly in line with the modern coal preparation plant's concept of "green sorting and efficient recovery".
Roller Screen Application
- Preparation For Raw Coal Screening
In the raw coal preparation workshop of the coal preparation plant, coal and gangue are separated in advance. The gangue larger than the screen holes enters the crushing system or is directly discharged, while the coal smaller than the screen holes directly enters the subsequent washing system, which can significantly reduce the load on subsequent equipment.
- Coarse-Grained Classification
With the widespread adoption of underground mechanized coal mining, the proportion of fine and fine-grained coal in raw coal and the moisture content have significantly increased. Some materials are wet and sticky. Traditional vibrating screens are prone to clogging the mesh holes, resulting in not only a decrease in screening efficiency and processing capacity, but also short service life, dust emission, and frequent failures. Therefore, many coal preparation plants have switched to using Roller Screens for the coarse classification of raw coal, effectively solving the problem of screen blockage, and achieving good operational results.
- Fine Particle Removal
In recent years, coal preparation plants have applied roller screens to the fine particle removal operation of materials smaller than 6mm, in order to reduce the processing cost of the coal slurry system.
- Coal Conveying System Of Power Plant
In the coal conveying system of a thermal power plant, it is installed in front of the coal crusher to separate the coal gangue and large impurities from the raw coal, protecting the coal crusher and improving the system efficiency.
- Garbage And Waste Disposal
Due to the fact that the Wobbler Feeder is less prone to clogging and can handle various dirty and miscellaneous materials, it has also been widely used in the sorting of construction waste and household garbage, achieving the recycling of resources.
If you would like to know the parameters, quotations and customization plans for the special Roller Screen for coal gangue, please feel free to contact us at any time. We have many years of experience in the production of mining screening equipment. We provide mature equipment solutions for the screening of high moisture and wet sticky raw coal and large-sized coal gangue. We can offer one-stop services including on-site condition survey, non-standard customization, on-site installation and commissioning. We look forward to cooperating with all coal mines, coal preparation plants and power plants!
