1. What is the sorting process and principle of jigging beneficiation processing?
Jigging beneficiation is carried out in a jig machine. The basic structure of all types of jig machines is similar, and its separation process is carried out in a jigging chamber. The jig chamber has a screen plate in the middle layer, from under the screen plate a vertical alternating water flow is fed periodically, and the ore is fed above the screen plate to form a dense layer of material called the layer, where the water flows through the screen plate and the layer. During the rise of the water flow, the layer is lifted and loosened, and the light minerals rise faster with the water flow, while the heavy minerals rise slower; while when the water flow falls, the light minerals fall slower, while the heavy minerals fall faster. In this way, the heavy minerals tend to the bottom, and the light minerals are located in the upper layer. As the water flow continues to fall, the layer looseness decreases and the movement of coarse particles is hindered. Later the layer becomes more and more compact, only the fine particles can pass through the gap downward movement, called “drilling gap movement”. The downward flow of water stops, the stratification effect also stops, this is a cycle. Then the water flow begins to rise again, starting the second cycle. This cycle continues, and finally the denser particles are concentrated in the bottom layer, and the less dense particles are located in the upper layer, completing the process of stratification by density, as shown in the following Figure. After being discharged separately with a special discharge device, products of different densities can be obtained. The above is the sorting process and principle of jigging beneficiation.
(Black particles in the figure indicate heavy minerals)
a-particle mixing and accumulation before stratification;
b-rising water flow lifts the mineral layer
c-particles settling in water stratification
d-flowing water drops, mineral layer dense, heavy minerals come to the bottom layer
2. What are the main types of jig machines?
Jig machine is suitable for processing coarse and medium grain ore, the upper size limit is 50 mm, the lower limit is 0.2-0.074 mm, preferably 18-2 mm. It is commonly used in coal, tungsten, tin and gold ore, it can also be used to select iron, manganese ore and some non-metallic ores. There are many types of jig machines, mainly piston jig machine, diaphragm jig machine, air pulsation jig machine, hydraulic pulsation jig machine, and dynamic screen jig machine. The most used in metal mining processing plants is the diaphragm jig machine. Diaphragm jig machine can be divided into different positions according to the installation of the diaphragm: side moving diaphragm jig machine: the diaphragm is located next to the jigging chamber, lower moving diaphragm jigger (cone diaphragm jigger): the diaphragm is horizontally located below the jigging chamber, lateral side moving diaphragm jigger: the diaphragm is vertically installed on the lower sidewall of the chassis screen, there are external and internal diaphragms. Mainly dealing with coarse leaching of ore, beneficiation efficiency is high. Air pulsation jig machine is commonly used in coal beneficiation industry.
3. What are the factors affecting the jigging sorting process?
Factors affecting jig sorting process as follows:
(1). Length and frequency of stroke. This is an important factor in the jigging process. The length and frequency of stroke determine the speed and acceleration of the water flow and the looseness of the layer in the jig machine. The length and frequency of stroke are related to the particle size, density and layer thickness of the sorted material. It is appropriate to use a large length stroke and a small frequency stroke to sort coarse materials, and a small frequency stroke and a large length stroke to sort fine materials.
(2). Water consumption. The water consumption of the jig machine has two aspects, namely the water on the screen added from the feed end and the water added under the screen. The larger the amount of water on the screen, the faster the discharge of light products, the larger the processing capacity, but the stratification is not complete, the light products are easy to mix with the density of larger particles. The main role of the water under the screen is to enhance the upwash water flow, so that the layer is loose and conducive to sorting.
(3). Layer thickness. The thicker the layer, the longer the time required to loosen the layer, the longer the time of stratification. When the density difference between large density particles and small density particles are large, the layer can be thinner; density difference is small, the layer can be thicker. When the layer layer is thick, the quality of heavy products increases and the quality of light products decreases. When the layer is thin, the quality of heavy products decreases, and the quality of light products increases. The factors that affect the jigging process include the area of the jig machine screen surface, the size and shape of the screen holes, the size and uniformity of the feed volume.