Operation method of cyclone for dry tailings discharge
Writer： admin Time：2020-08-03 11:16 Browse：℃
Hydrocyclones are widely used in slurry concentration and clarification, particle classification, desliming and demedication, etc. In recent years, hydrocyclones have been successfully applied in the tailings treatment process and have become an indispensable equipment in the dry tailings screen developed and produced by Longzhong Heavy Industry. Today, cyclone manufacturers share common faults and maintenance methods of hydrocyclones with users.
What should I do if the sedimentation of the cyclone is discharged in a rope shape? The sedimentation is discharged in an umbrella shape. The judgment basis is that the angle of the sedimentation is between 10°-20° and the concentration reaches about 75%, which is the best working condition. If the grit spreading angle is too large, there are three reasons why the grit nozzle is too large and the grit concentration is too low. At this time, it can be adjusted by replacing the small sand spout. If the feed pressure is too small, the feed pressure of the pump should be adjusted to meet the technological conditions. The feed amount is too small and the feed concentration is too low. At this time, the amount of ore and the number of cyclones can be adjusted. In short, the size of the sedimentation concentration directly affects the efficiency of the mill, the particle size of the mill's discharge, and will affect the entire process. There are more coarse particles in the overflow, and the sediment is discharged in a columnar shape, which proves that the cyclone is clogged, which should be eliminated in time and adjusted according to the above adjustment.
The grit is discharged in a rope shape, which proves that the feed concentration is too high, and the feed concentration should be adjusted in time. The long-term violent shaking of the cyclone proves that the cyclone is blocked. It is necessary to reduce the pressure and increase the number of cyclones or replace the large sand nozzle to eliminate it.
(1) The diameter and height of the cylindrical cylinder. This diameter is the main size of the cyclone. It has the relationship with the size of other parts: the diameter of the cylinder increases, which can improve the processing capacity, but the overflow particle size becomes thicker, and vice versa.
is also true. In order to classify fine-grained materials and increase the processing capacity, a group of small cyclones is usually used in parallel. The height of the cylindrical barrel has an effect on the residence time of the slurry in the cyclone, that is, the classification efficiency.
influence, generally 0.6-1.0 of its diameter.
(2) Give the diameter of the mine mouth. This diameter is usually 0.08-0.25 of the diameter of the cyclone, more than this value can increase the throughput, but the classification efficiency is reduced.
(3) Diameter of overflow pipe. This diameter is generally 0.1-0.4 of the diameter of the cyclone, which can be used to adjust the relative yield of overflow and sedimentation. The diameter of the overflow pipe increases, the overflow flow increases, the overflow particle size becomes coarser, and the fine particles in the sedimentation decreases.
The density increases.
(4) Diameter of grit port. It was found through observation that the diameter of the grit port increased, the overflow flow decreased, and the overflow particle size became finer, while the amount of grit increased, the concentration decreased, and the fine particles increased, but there was no significant effect on the processing capacity. Diameter of grit port becomes smaller
, the amount of grit discharged is reduced, and the phenomenon of "roughing" will appear in the overflow. If it is too small, the coarse particles will accumulate more and more on the top of the cone, resulting in blockage. The proper diameter of the grit port should be such that the grit is discharged in an umbrella shape with an angle of
400-700. The ratio of the diameter of the grit port to the diameter of the overflow pipe is generally 0.4-0.8.
(5) The cone angle of the conical cylinder. The specific effect of this cone angle is: increasing will reduce the height of the equipment and increase the average radial velocity of the slurry. At the same time, due to the increase of the blocking effect of the cone, the upward velocity of the slurry increases, resulting in
Make the overflow granularity coarser. Therefore, a large cone angle cyclone (30°-60°) is used when the separation particle size is coarse, a small cone angle cyclone (15°-30°) is used when the separation particle size is fine, and a smaller cone angle is used for desilting. Device
(10°-15°).
process operation
The beneficiation process operation is mainly manifested in the feeding pressure; the commonly used feeding pressure is 49-157kPa (0.5-1.6kgf/cm2). The feed pressure is directly related to the processing capacity and the separation particle size. When the pressure on the mine increases,
Reduce the classification particle size and increase the processing capacity, but this kind of writing will also significantly increase power consumption and equipment wear. Therefore, it is sufficient to keep the mine pressure stable during normal work.
Feeding properties
Pulp properties: the higher the density of the ore, the finer the grading particle size. When the slurry concentration is high and the mud content is high, its viscosity and density increase, which increases the movement resistance of the particles and makes the classification particle size coarser. vice versa.
How to operate the dry tailings cyclone:
1. The operating process of the dry tailings cyclone
The process has made many beneficial improvements in the aforementioned various concentrated water solutions, and discarded the advantages and disadvantages of the existing process, such as using a dewatering screen to replace a belt filter or a sludge hopper to treat the cyclone underflow. At the same time, the hydrocyclone-thickener series process is retained as part of the overall process. Finally, a filter press is used to process the underflow of the thickener to achieve a complete dry pile of tailings.
2. Advantages of the dry tailings cyclone process
1. The process has targeted treatment for both coarse and fine materials in the tailings slurry. The cyclone is used to classify coarse and fine particles, and the coarse particles are processed by a dewatering screen. When the concentration of the cyclone underflow reaches 65%-70%, the dry pile effect is not ideal for iron tailings. Using a dewatering screen to treat the cyclone underflow can further increase the underflow concentration to 80% the above. At the same time, the product under the sieve is pumped to the cyclone to form a closed circuit system, so that the return water can be obtained from the filter press and the thickener.
2. The overflow of the cyclone is fed into the thickener, which can overcome the overflow of the thickener and greatly reduce the pressure of the thickener. It is beneficial to increase the concentration of the concentrated product, reduce the diameter of the thickener, and save space. With the use of flocculants, the underflow concentration of the thickener can quickly reach about 45%, but it cannot meet the requirements of dry pile. The use of filter press to process the underflow of the thickener can further increase the moisture content of the material while obtaining clarified backwater, and meet the requirements of dry feeding. At the same time, since only fine-grained materials need to be processed, the processing capacity of the filter press is reduced, the number of units used can be reduced, and the cost is saved.
3. In summary, after the tailings are processed by this process, the dry material coarse particles are obtained by the dewatering screen, and the fine particles are obtained by the filter press, which can achieve the ideal dry pile effect. The thickener and the filter press can be produced. The discharged backwater is directly returned to the processing plant for use.
