The magnetite beneficiation process is the most widely used dry-wet combined beneficiation process. It mainly conducts three-stage magnetic separation treatment on the ore powder, and then undergoes wet magnetic separation. The magnetic field strength selected for the magnetic separation is 400~ 1200GS, the rotating speed of the magnetic drum is 60～320 rpm, the wet material is dehydrated to obtain finished iron ore concentrate powder, generally the ore with iron content of 35%, the iron content of iron ore concentrate powder can reach 68～68% after magnetic separation by this method. 70%.
Detailed explanation of magnetite beneficiation process
The magnetic separation process is mainly divided into three parts: crushing process, grinding process and sorting process.
Crushing process: The hardness of the iron ore is relatively large, so a large jaw crusher is used for rough crushing. A vibrating feeder is added in front of the crusher, and the mineral raw materials are evenly fed into the jaw crusher. -75mm two grades, the +75mm grade enters the jaw crusher for rough crushing, and the -75mm grade enters the cone crusher for crushing.
Grinding process: Due to the high hardness of the ore and the extremely fine particle size embedded, it is difficult to achieve the desired output and monomer dissociation by the ordinary one-stage grinding process. This process adopts a two-stage grinding process, which not only reduces the amount of minerals The sludging of the ore and the reduced efficiency of the mill caused by over-grinding can also increase the output and achieve the required grinding fineness.
Selection process: The selection process adopts 3 permanent magnet drum magnetic separators, one magnetic separator is used for the first-stage selection, and one rough magnetic separator and one selective magnetic separator are used for the second-stage selection. In order to meet the requirements of concentrate grade above 63. The separation process adds a demagnetization process to remove the magnetic properties of the minerals themselves after magnetic separation, so as to avoid the generation of magnetic chains and affect the improvement of the concentrate grade.
Magnetic separation process (note that this process is for reference only, different processes should be selected according to different ores).
Raw ore—vibrating feeder/trough feeder—PE jaw crusher—PEX jaw crusher—vibrating screen—dry selection roller—silo—electromagnetic vibrating feeder/pendulum feeder—ball mill— Spiral classifier/high frequency screen - magnetic separator (selected) - [magnetic separator (sweeping) - tailings] - [magnetic separator (selected) - wet concentrate - thickener (optional) - dry Powder]
1. Less water consumption in the process, saving water and reducing costs.
2. Reduce pollution, the magnetically selected dust is captured by the dust removal device, which will not cause air pollution.
3. High production efficiency and good product quality.
4. The equipment has a large selection range, which is conducive to improving the grade of finished ore.