The selection and adjustment of coal feed is an important factor affecting the separation effect of jig. The coal supply should not be too small. Too small, the equipment capacity can not be exerted, and even the loss increases and the quality becomes worse. However, it is not advisable to give too much coal, which will lead to the increase of gangue-bearing coal and the deterioration of clean coal quality.
In coal preparation, we should try our best to keep the balance and stability of coal supply. This requires that the coal should be put into the bin before unloading, so that the coal in the buffer bin should be kept above half a bin. In this way, the influence of particle size segregation in the bin on the separation process is avoided, and the coal feeder can also feed evenly and continuously along the whole width of the jig. However, because the raw coal in coal preparation plant often comes from different mines or different coal seams in the same mine, the coal quality changes greatly, and the operators need to make decisions according to the specific conditions of the incoming materials.
Influence of feng shui volume
In the process of jig separation, when the coal quality is relatively stable, the parameters of jig should be as stable as possible to stabilize the separation effect. Among them, air volume and water quantity are very important factors. It not only determines the jumping height (range) of the bed, but also determines the swimming of the bed. Regarding the cooperation of geomantic omen, the following points are worth noting.
(1) There are many fine particles in raw coal. In this case, the horizontal flushing should be reduced as much as possible under the condition of ensuring the complete wetting of raw coal, and the water consumption at the top should be reduced room by room along the length of jig. The front of jig adopts big water and small wind to prevent fine materials from being screened prematurely; In the middle of the jig, the air volume can be increased, so that the fine materials with poor quality can be layered and discharged through the screen.
(2) When the quality of coarse fraction in raw coal is good and the quality of fine fraction is poor, the general method is to strengthen screening and enhance suction. The adjustment of air valve adopts the principle of short air intake time, long exhaust time, large air volume and small water volume.
(3) The quality of coarse fraction in raw coal is poor, and when the quality of fine fraction is good, screening should be reduced, and heavy products should be discharged from the screen, so the rising period should be strengthened and the falling period should be weakened. The adjustment of the air valve is generally a long intake time and a short exhaust time.
(4) When the raw coal is uniform in particle size and good in quality, the operating system of small wind and big water should be adopted; When the granularity of raw coal is uniform and the quality is poor, the operation system of strong wind and small water should be adopted. The combination of geomantic omen and geomantic omen is the leading factor to ensure that beds are sorted by density. Xinhai jig adopts electromagnetic stepless speed regulation, which has the advantages of uniform stirring, stable ore flow, wide adaptability of material selection and good separation effect of medium and fine particles. Usually, people sum up the function of Feng Shui as "wind energy guarantees quality and water energy guarantees quantity". When quality problems need to be solved, we must make suggestions on using the wind; When it is necessary to wash more coal and increase the handling capacity, it is necessary to make a fuss about water use. The use of geomantic omen should not be excessive or insufficient. The air volume should be based on stabilizing the bed and maintaining the density of the bed, and the water volume should be based on ensuring the bed to swim. The proper standard of feng shui cooperation is that the bed is stable and the materials are layered according to density.
Impact of emissions
The final effect of the product depends on the discharge system under the condition of stable feeding quantity, proper use of feng shui quantity and good layering effect. Correct layout is one of the important factors to ensure product quality.
The discharge of the main dressing section should not be too big or too small. If the discharge is too large, it will increase the loss of coal in gangue, make the bed too thin, make the bed disordered, which is not conducive to separation. If the flow rate is too small, it is easy to make the bed thicker, and the bed can't jump over the same amount of geomantic water, so the looseness is small. Therefore, the materials can't be sorted well, so that large coal is mixed with gangue, and at the same time, some fine gangue is mixed with clean coal, which not only affects the product quality but also increases the loss; Moreover, it is often easy to pile up coal if the layout is not timely. In this case, it is sometimes necessary to suddenly discharge waste rock. Improper discharge of gangue in the first stage will not only increase the loss of coal in gangue, but also affect the separation in the second stage.
In the case of good emissions in the first stage, the emissions in the second stage should be as stable as possible. The quantity and quality of secondary coal discharged from the main concentrator not only affect the quality and output of clean coal products, but also directly affect the coal feeding quantity and feeding properties of the concentrator. In a word, we should pay attention to the reasonable cooperation between the first and second paragraphs in the discharge.