Geavity Separation Method and Jigging Machines

Gravity Separation Method :-

Gravity separation method is a traditional methods for treatment of tungsten, tin, gold ore, especially when dealing with gold dust, sand tin. In dealing with rare metals (niobium, tantalum, titanium, zirconium) of the placer application is also very common. Re-election is also used to sorting the weak magnetic iron ore, manganese ore.

The application of Gravity separation method:-

Gravity separation method is useful for re-election deal with the gangue minerals with large density difference between the ore and other raw materials. It is a effective way to dealing with Coarse-grained, medium-and fine-grained ore (generally limit is greater than 25 mm, 25 "2 mm, 2 ~ O.1 mm), but the efficiency is not high when in dealing with fine mineral mud (less than 0.1 mm), the flow of modern film processing equipment can be effectively recycled to the 20-30 micron grain size, centrifugal concentrator to 10 microns can be.

Gravity separation method in non-metallic mineral processing industry has also been developed in recent years, mainly used for treatment of asbestos, diamond, kaolin, apatite, pyrite and other minerals. In the election of copper, lead, zinc, antimony, mercury sulfide ore flotation plant, often used method of gravity concentration for primary election. Gravity separation method usually combined with other beneficiation process in the main election process, to select out the Concentrates or tailings in the state of Coarse-grained in advance.

This will help reduce production costs and metal loss. The Gravity separation method is always a priority, when there a variety of processing ore methods.

Gravity separation method must conduct in certain fluid media, Medium usually by water, Also use medium by air or heavy-medium (heavy liquid or dense medium). Media moved in a certain way inside separation equipment. Mineral grain begin loose with the effect of Medium buoyancy and hydrodynamic, and then to press the density (and sometimes by size) stratified. Layered mineral particles affect the nature of the process is its density, size, and minor shape factors.

Gravity separation method process method:-

There are several Gravity separation methods according to the Media campaign form and purpose of the job:

1) .Classification

(2) Heavy Media Beneficiation

(3) Jig Beneficiation

(4) Shaker Dressing

(5) Ore Chute

(6) Spiral Concentrator

(7) Centrifugal Dressing

(8) Wind Dressing

(9) Washing
Grading and washing operations are separated according to size, used in the preparation of the ore before enrollment. Other processes is substantial sorting operations, this is the following content will be described by this article.

The basic principle Gravity separation method:-

The essence of Gravity separation method can be summed up the separation process of loose – layered. Placed in Granular layer of ore in separation equipment.
Make a different density (or size) to switch a shift layered particles occurs, for re-election is to be achieved by density stratification. It begin to loose when drive by Fluid buoyancy, power or other mechanical forces, Purpose is to make a different density (or size) to switch a shift layered particles occurs, For Gravity separation method is to be achieved by density stratification.
Therefore, the role of fluid loose particles must the request of group stratification. This is the way to distinguish Gravity separation method from other two project of the Department. Fluid loose in different ways, the results of stratification is also affected.

The theory of gravity separation method, in short, it is about the relationship between Loose and layered. Stratified ore were discharged under the mechanical action; Stratified ore were discharged under the mechanical action. It can be considered is the condition of loose, layered is the goal, and the separation is the result, the method of gravity separation process that is the means to achieve this process

The work are controlled some basic principles such as
1. Settlement of particles and particle swarm theory
2. Particle group according to the theory of density stratification
3.Particle group in the slope flow separation theory　
There are also rotating flow in the sorting, although the media campaign in different ways. But in addition to differences in gravity and centrifugal force, the basic role of the law is still the same.

The theory about Stratified according to density swarm, Was first to start the study from the process of jigging。It has made a lot of jig stratification theory, and later appeared in a number of specialized vertical flow: the theory of stratification

Slope flow dressing was first in the thick layer of water over coarse ore processing, sorting is based on the particle velocity along the trough difference. After 1940， Slope to the stream beneficiation switch to the development of flow membrane dressing, Mainly used to sorting and micro-fine particles of ore fine. Fluid state divides into laminar flow and turbulent flow. That the turbulent fluctuating velocity is always loose bed of view of basic forces in laminar flow conditions, that is difficult to explain. 1954 R. A. Bai Genus (Bagn0ld) proposed interlaminar shear repulsion theory, Adds to this interesting theory on the blank.

However, as with the hierarchical theory，Inclined to rely on the existing flow of ore to make a reliable theoretical calculations is still difficult.

Although the theory of gravity separation to this day not reached the perfect point yet, but many of the processes and disciplines, as it already provides basic guidance for the production, and as similar to mathematical statistics and as the basis of the study and simulation.

Jigging Machines:-

Jigging machine belongs to gravity-based equipments, which can separate mineral based on differing of specific gravity. “Gandong” saw-tooth wave jig is mainly consist of three parts: main frame, driving set and jigging chamber.

Features:-The pulsing curve of the traditional jig is sinusoidal waveform, the up and down speed of water flow and acting time produced by the movement of membrane are almost same, so it is unfavorable to loose of jig bed and layering of minerals based on special gravity, and thus affect separation ability and recovery rate. Saw-tooth wave is an energy economy gravity equipment that is developed and improved from traditional jig on the basis theory of jig bed layering. Its jigging pulsating curve is similar to saw-tooth wave, which makes the up speed of water flow quicker than down speed of water flow, so it can improve looseness of jig bed and reduce suction action, which can lead to fully settlement of heavy particles in slurry, it highly improves separation ability and recovery rate. Stroke and frequency of stroke are adjustable.

Application:-Jigging machine is widely used in gravity concentration of tin, tungsten, placer gold, hematite ore, manganese, titanium, antimony, lead, tantalum, niobium and other minerals.