Depending on the medium forms of exercise and operating purposes, gravity separation can be divided into six operations:
1) heavy media beneficiation. Re-election must be conducted in the media, with media air, water, and re-solution or the re-suspension, one of the most commonly used are water, air, called wind beneficiation, with density greater than water weight liquid or re-suspension is known as a heavy media beneficiation. The heavy media beneficiation is a strictly mineral density sorting method.
2) classification. Of granular material in the settlement of the air or water, the particles of different size and shape suffered different media resistance and settling velocity, this time according to particle size separation, and this re-election operation known as classification.
3) washing. Ore clay cement interfere with follow-up operations requires the use of the washing operation, it is with the help of the flow momentum and mechanical force to the clay and ore block away from the job.
4) jig beneficiation. Periodic vertical speed change of medium flow, repeatedly loose mineral particles group, intensive press the density stratification re-election process is known as the jig beneficiation.
5) shaker dressing. The inertia force generated by the reciprocating motion of the shaker surface asymmetry and water flushing effect, so that the swarm at the surface of the bed loose layering and haulage zoning, in order to achieve the job of sorting.
6) chute dressing. Beneficiation by means of chute flow of liquidity
Spiral classifiers are widely used for distributing ore in the close circuit with ball mill, grading ore and fine slit in the gravity mill, grading granularity in the flow of metal ore-dressing and desliming and dehydrating in the washing. Advantages are simple structure, reliable working condition and convenient operation. According to the principle that different grains are