I. Heavy Media Beneficiation

Heavy media beneficiation refers to the beneficiation process carried out in the medium with a density greater than 1000 kg/m3. The density of the medium is generally selected between the density of light minerals and heavy minerals in the minerals, when the density of the medium is strictly controlled (fluctuation range ≤ 20 kg/m3), the density difference of only 50~100 kg/m3 of the two minerals can be effectively separated.

Heavy beneficiation is mainly used in ore pre-selection, that is, in the coarse-grained conditions to select the veinstone or peridotite, reduce the amount of fine grinding and deep selection of ore, and improve the grade of selected ore. At present it has been widely used in the treatment of iron, manganese, lead, zinc, tin, antimony, gangue, diamond and other metal and non-metal ores. The upper limit of the particle size of the selected stone is 50~150mm, and the lower limit is 2~3mm.

Heavy media beneficiation process includes ore preparation, media preparation, ore sorting, media removal, media regeneration and other operations. Heavy media beneficiation separation density can be precisely controlled, can make the density difference is very small minerals effectively separated. The processing capacity per unit area is large, and the cost of beneficiation is low. General small and medium-sized processing plant is less used.

Second, jigging beneficiation

Jigging beneficiation is one of the main methods of gravity beneficiation, belonging to the deep trough sorting operation. Jigging beneficiation, in addition to very fine materials, can deal with almost all kinds of particle size of mineral raw materials, process operation is simple, equipment processing capacity, and can get a certain product in a selection, so the production application. With jigging to deal with raw coal accounts for about 40% of the total coal selection. For metal ores, it is the main method to deal with coarse and medium grained iron ore, manganese ore and chrome ore. And a large number of used in the selection of unevenly embedded tungsten, tin ore of the coarser grain part. Jigging is useful for treating gold-bearing alluvial ores, primary ores and alluvial ores containing niobium, tantalum, titanium and zirconium, and it is also the main method for separating diamonds. The greater the difference in density of the minerals to be separated from the ore, the wider the range of particle sizes can be selected. For example, for alluvial gold ore in the feed size of less than 25mm, can not be classified into the selection, recovery size lower limit can be 0.04mm. but for general metal ores to implement the classification into the selection can effectively improve the index of separation and improve the equipment processing capacity.

In the specific gravity difference ≥ 1.25 and ore monomer dissociation under the premise of jigging machine can be selected particle size selection of coal for 150 ~ 2mm, selection of other minerals between the particle size range of 50 ~ 0.1mm, selection of alluvial gold the lower limit of the particle size of up to 0.04mm.

Third, shaking table beneficiation

Shaking table belongs to the flow film mineral processing equipment, from the plane chute development, later to its asymmetric reciprocating motion as a characteristic and self-contained system.

Shaking table is a commonly used equipment for sorting fine-grained ores, the effective size range of metal ores is 3~0.019mm, and the upper limit of coal size can be up to 10 mm. shaking table has high sorting accuracy, and high grade concentrate or waste tailings can be obtained by one sorting, and multiple products can be picked up at the same time. Plane shaking table is easy to look after and convenient to adjust.

Fourth, chute beneficiation

Chute beneficiation belongs to the inclined flow sorting process. Slurry to a certain inclined inclined chute or inclined surface, driven by the water flow, the ore group loose stratification, the upper layer of fine minerals quickly discharged out of the tank, the lower layer of heavy minerals are retained in the tank or discharged from the lower part of the low speed. Separate pick up, that is, the concentrate and tailings.

Chute is the early appearance of mineral processing equipment. Equipment structure is simple, low investment and production costs, coarse and medium grain chute has a higher processing capacity.

Fifth, spiral beneficiation

Spiral beneficiation is bent into a spiral long trough in the beneficiation process, still belongs to the oblique flow beneficiation category, but here the use of the slurry in the rotary movement of inertial centrifugal force, prompting the fine heavy minerals in the groove on the surface of the sub-band, and respectively, continuously discharged.

(A) spiral concentrator

Spiral concentrator has simple structure and no moving parts. Covering a small area, the unit capacity is larger, operation and maintenance is relatively simple. The machine is suitable for processing sand ore containing less mud, the feed size in 2 ~ 0.1mm, to 0.5 ~ 0.1mm. in the processing of high mud-containing vein ore grinding products should be desliming or grading, otherwise it will reduce the quality of concentrate and recovery rate.

(ii) Spiral chute

Slurry flow in the spiral chute and sorting principle and spiral concentrator is basically the same. Only in the spiral chute groove surface has a greater gentle width, the slurry is laminar flow flow area is larger, so it is suitable for processing fine-grained ore.

Spiral chute structure is simple, large capacity, easy to operate, low production costs, suitable for processing 0.6 ~ 0.03mm vein or sand ore.

Sixth, centrifugal beneficiation

Centrifugal beneficiation mainly with the help of centrifugal force, accelerating the settling of fine particle size and stratification speed, suitable for dealing with -0.1mm fine-grained minerals, due to the production cost is relatively high compared to the general method of gravity selection of minerals, and the recovery of 37 ~ 19 micron particles with very good results. At present, it is mainly used for processing micro-fine grade materials with high value, such as tungsten.

Compared with the shaking table, in the processing of 0.037 ~ 0.019mm materials, centrifugal concentrator covers an area of less, large capacity, saving power consumption, but its concentrator enrichment ratio are lower, and its concentrate needs to be selected with a belt chute in order to reach the concentrate. Centrifugal concentrator is mainly used to replace the fabric chute process.