Although the vibrating screen is not very conspicuous in the whole crushing equipment, it is undeniable that it is also one of the indispensable main equipment in material crushing and sand making operations.
What are the uses of vibrating screen in sand crushing?
- Material pretreatment. If the particle size of crushed materials varies greatly as a whole, screening and grading can be carried out first to make the feed particle size reach the standard; For materials with small particle size, screening can also be carried out before crushing and sand making to preliminarily reduce the silt content in the crushed materials.
- Secondary screening. After primary crushing and secondary crushing, materials need to be further screened and graded. If the particle size reaches the treatment standard, they will continue to enter the next stage of crushing or sand making. If the particle size does not meet the standard, they will continue to be crushed until they reach the particle size standard for the next treatment process.
- Screening of mud powder. After sand making, the materials are usually washed with sand, and the sewage after sand washing is mixed with mud powder. In order to recover fine sand and dust lost during sand washing, vibrating screen can be configured to screen and collect mud powder in sedimentation tank.
Introduction to dust removal method of mine vibrating screen crusher:
① Enclose to prevent dust. For equipment with serious dust, sealing measures can be taken to control the dust within the scope of small space, small maintenance workload, and infrequent access of personnel, and then cooperate with dust removal equipment to prevent dust from flying. The parts that are more suitable for this method are: vibrating screen, crusher, etc.
② Spray water to prevent dust. In the concentrator, the common dust prevention measure is sprinkling water. Since most of the operations after crushing in the concentrator are wet operations, they will not affect the following operations, and water supply will not become a major problem. However, for the normal operation and progress of the crusher, screening equipment and ore storage, the moisture in the ore should not be too large, generally not more than 5%.
③ Other measures. Control the dust pollution caused by material leakage of the belt conveyor during transportation by strengthening the cleaning function of the belt after unloading. For example, the belt cleaner can wash the belt if possible.
The dust sources of the crusher mainly include the dust generated at the feeding port, the dust generated at the discharge port and the dust generated when the chute is not tightly sealed.
- Dust production at the feeding port: when the crusher is working, the coal is squeezed and impacted, making the air in the pulverized coal gap squeeze out violently. When these air currents move outward at a high speed, due to the shear compression of the air flow and dust, the dust will escape together, raising a large amount of dust instantly. Because the chute of the crusher is closed around, the dusty air flow can only be discharged downward (a small part) through the chute or upward (most) through the feeding port, which generates high concentration of dust around the feeding port.
- Dust at discharge port: after coal dust is crushed, it is discharged to the receiving equipment (belt conveyor) at the lower part of the crusher through the chute. As there is a drop between the feed port and the discharge port, the pulverized coal flow shears with the surrounding air, the air is entrained into the material flow, the pulverized coal flow gradually diffuses, and the mutual entrainment makes the dust continuously fly outward; At the same time, the belt of the conveyor has a movement speed, and the impact of the pulverized coal flow and the belt surface will instantly raise dust at the discharge port and fly around. The dust concentration at the discharge port is related to the type of coal, the dryness and wetness of coal, the drop of chute, and the movement speed of conveyor belt.
