Flotation process and equipment

That flotation froth flotation beneficiation methods is to divide the mineral composition according to different physical and chemical properties of the mineral surfaces.

4.1 flotation process

During the flotation process, the ups and downs of minerals are almost independent of mineral density. Such as brass and mineral quartz, the former density of 4.2, which is 2.68, but the heavy mineral chalcopyrite readily float, but quartz settle to the bottom. It has been found that the floatability of minerals is related to the affinity of water. Any mineral that has a high affinity with water and is easily wetted by water is difficult to adhere to bubbles. Minerals that have low affinity with water and are not easily wetted by water are easy to float. Therefore, it can be said that flotation is a beneficiation method based on the difference in mineral wettability of minerals. The nature of minerals that are easy to float and difficult to float is generally referred to as the floatability of minerals. Flotation is the use of the difference in the floatability of minerals to sort minerals. In the modern flotation process, the application of the flotation agent is particularly important, because after the flotation agent treatment, the floatability of the mineral can be changed, so that the mineral to be floated can selectively adhere to the bubble, thereby achieving the purpose of beneficiation.

Flotation is the same as other mineral processing methods. It is necessary to prepare the materials before the sorting, that is, the ore should be graded by grinding to achieve the concentration fineness suitable for flotation. In addition, there are several basic operations for flotation:

1. Adjustment of pulp and addition of flotation reagents

The purpose is to cause the difference in the surface properties of the mineral, that is, to change the wettability of the mineral surface, to adjust the selectivity of the mineral surface, so that some mineral particles can adhere to the gas, while others can not adhere to the air bubbles.

Second, stir up and cause a lot of bubbles

By means of the aeration stirring action of the flotation machine, the air in the slurry is dispersed to form a large number of bubbles, or the air dissolved in the slurry is formed into a micro-saturated state.

Third, the mineralization of bubbles

The ore particles selectively attach to the bubbles, which is the most basic behavior in the flotation process.

Fourth, the formation and scraping of mineralized foam layer

The mineralized bubbles rise from the lower part of the flotation tank to the mineralized surface to form a mineralized and saturated layer, and the useful minerals are enriched into the foam, which is scraped out to become a concentrate (middle mine) product. The non-target minerals remain in the flotation cell for sorting purposes. Generally, the minerals floating in the flotation operation are useful minerals. Such flotation process is called positive flotation. Conversely, if the floating mineral is gangue, it is called reverse flotation (or reverse flotation).

The flotation process is a more complicated ore processing process, and its influencing factors can be divided into non-adjustable factors (original ore and water quality of production water) and adjustable factors (flotation process, grinding fineness, slurry concentration, pulp pH, Flotation pharmacy system).

4.2 flotation equipment

In order to achieve the separation between the ore particles, the mineral surface must have different wettability, and the quantity and quality of the foam to meet the needs, and there should be suitable mechanical equipment to separate them into products of different nature and quality. The device is a flotation machine. The flotation machine is an important device for implementing the flotation process. The effect of flotation has a considerable relationship with the performance of the flotation machine in addition to the effects of chemicals and process. To this end, countries have done a considerable amount of work in improving and developing flotation machines.

Flotation machine type: mechanical agitation flotation machine, inflatable flotation machine, hybrid flotation machine or aerated agitation flotation machine, gas precipitation flotation machine.

(1) Mechanical agitating flotation machine

The characteristics of the mechanical agitation flotation machine: the aeration and agitation of the slurry are realized by a mechanical agitator. It belongs to the external gas self-priming flotation machine. The aeration agitator has a pump-like suction characteristic, which is self-priming air. Self-priming slurry.

XJK flotation machine (commonly known as type A) is characterized by:

First, 18 to 20 guide vanes are mounted on the cover.

Second, the impeller, the cover plate, the vertical shaft, the intake pipe, the bearing, the pulley, and the like are assembled into an integral component.

Third, a circle of upright fins is placed around the trough to prevent eddy currents from occurring in the slurry.

(2) Inflatable agitating flotation machine

Its characteristics are: 1. The amount of inflation is easy to adjust separately; 2. The mechanical agitator wears little; 3. The selection index is better; 4. The power consumption is low.

Denver-type flotation machine: 1> effective gas filling amount; 2> a slurry upwelling flow is formed in the tank.

(3) Inflatable flotation machine

Inflatable flotation machine: 1, structural features: no mechanical agitator without transmission parts; 2, inflatable features: aerator inflated, bubble size adjusted by the structure of the aerator; 3, bubble and slurry mixing characteristics: countercurrent mixing. Uses: handling rough, sweeping selection with simple composition, high grade, easy to select ore

Flotation column: simple structure, small floor space, convenient maintenance, easy operation and power saving.

(4) Gas precipitation flotation machine

The gas precipitation flotation machine is mainly used for flotation of fine-grained minerals and deoiling flotation of oily wastewater.