Low frequency AC electromagnetic washing machine

Abstract

The invention discloses a low frequency AC electromagnetic washing machine. The low frequency AC electromagnetic washing machine comprises a washing cylinder, a concentrated ore cone cylinder, an overflow device, an ore feed device, a water supply device, and a magnetic separator, wherein the magnetic separator comprises an ore gathering magnetic field coil sleeved at the peripheral top of the washing cylinder and a plurality of traveling wave magnetic field coils below the or gathering magnetic field coil, the ore gathering magnetic field coil is connected with single-phase low frequency AC,the traveling wave magnetic field coils are connected with a three-phase low frequency AC, a wiring manner of the traveling wave magnetic field coils is 'Y' shape or 'delta' shape, frequency of the lower frequency AC is lower than 50Hz, an induction magnetic ring is arranged in a position in the washing cylinder corresponding to the ore gathering magnetic field coil, an overflow inner cylinder andthe washing cylinder are identical in diameter, an ore outlet of the ore feed device is in the middle between the first traveling wave magnetic field coil and the second traveling wave magnetic fieldcoil and is in the middle of a distance between the inner wall of the washing cylinder and the outer wall of an ore feed tube, and the water supply device is arranged on the concentrated ore cone cylinder below the washing cylinder. The low frequency AC electromagnetic washing machine produces high quality concentrated ore, has good sorting effect and can be widely used.

Description

technical field [0001] The invention relates to the technical field of magnetic separation equipment, in particular to a low-frequency AC electromagnetic elutriation machine with improved quality and efficiency, energy saving and environmental protection. Background technique [0002] At present, domestic magnetic separation plants generally use magnetic separation equipment such as drum magnetic separators and magnetic desliming tanks. This type of equipment has a high magnetic field strength and a large magnetic field force, and has a strong magnetic agglomeration effect on the separation of magnetite. Therefore, there are inherent disadvantages such as "magnetic inclusions" and "non-magnetic inclusions", which make the concentrate contain more gangue, which seriously affects the grade of the concentrate. In addition, the process flow of this type of magnetic separation equipment is long and complicated, the circulation of medium ore is too large, the consumption of water...

AI Technical Summary

Problems solved by technology

Due to the properties of the DC power supply, the constant magnetic field coil only has the function of adsorption. After the concentrate powder is absorbed, it does not have the ability to roll over. Therefore, the internal inclusions cannot be squeezed out. When the absorbed mineral powder reaches a certain amount At this time, part of the ore powder breaks away from the constraints of the magnetic field and falls into the washing drum. Since it does not have the functions of tumbling and scrubbing, the non-magnetic inclusions inside the iron powder also fall into the washing drum, causing damage to the stable separation environment in the drum. Causes the output concentrate grade to be unstable

At the same time, the magnetic field along the cylinder wall to the center of the cylinder gradually decreases, making some areas in the cylinder a non-magnetic area and a weak magnetic area. For this area, when the water flow is too large, it is impossible to use the magnetic field to absorb the fine-grained concentrate that rises with the water flow. Therefore, the constant magnetic field coil has little effect in a stable sorting environment. When the water flow or pulp volume fluctuates too much, it cannot play a decisive role in ore control, resulting in runaway

The lower end of the ore feeding pipe is evenly distributed with ore distribution outlets along the circumferential direction. This method of ore distribution is to feed the ore in a way that coincides with the axis of the washing cylinder. The ore distribution mouth of the cloth flows into the rising water flow. Because the ore distribution mouth is far away from the inner cylinder wall, the magnetic field has a weak binding force on the ore slurry at this place. In this area, a magnetic chain cannot be formed basically, and the magnetic rolling effect cannot be produced. And because the settlement distance is too long Therefore, unreasonable ore distribution position and method and too long feed pipe cause too short settlement distance is one of the key factors affecting the quality of concentrate

[0005] Secondly, the water inlets of the traditional electromagnetic elutriation machine are evenly distributed on the horizontal circumference of the lower part of the washing cylinder, and holes are directly opened on the horizontal circumference, so that the water flow into the cylinder is in a disordered state, causing the concentrate that settles here to be disturbed again Breaking up will cause great damage to the enriched concentrate. Even if the enriched ore gathering coil with a constant magnetic field is installed at the lower part of the water inlet, it is difficult to adsorb the concentrate powder in the center of the washing cylinder, and it will not achieve good results. Enrichment

Therefore, it is inappropriate to set the water inlet at this position and the way of setting the water inlet; some manufacturers set the water inlet in the horizontal area of ​​the fourth and fifth coils, and connect the water pipe from the outside of the washing tube to the inside of the tube perpendicular to the At the axis of the washing cylinder, connect a water inlet pipe that coincides with the axis of the washing cylinder to the horizontal area of ​​the fourth and fifth coils, block the top of the water inlet pipe, and distribute water distribution pipes horizontally on the upper circumference of the water inlet pipe. A number of water outlets are evenly distributed on the same side of each water distribution pipe, so that the water flow is in an upward spiral state. Since the grade of the concentrate has reached the ideal state when it enters this area, it is the key stage of enrichment and accumulation. After the upward spiral Disturbance of water flow breaks up the preliminarily enriched concentrate powder again, which is not conducive to ore gathering

Moreover, in this area, the law of progressively improving water quality conditions from top to bottom in the water distribution and destruction cylinder shows that the water quality in the water supply area is the best, followed by the lower area, and the top area is the worst. The problem of recontamination

[0006] Moreover, the power supply of the traditional electromagnetic elutriation machine adopts DC excitation, and alternately energizes through the thyristor, so that an alternating pulsating magnetic field is generated between the coils. For example, when coils 1, 3, and 5 are energized at the same time, the concentrate powder located here forms Magnetic linkage, the concentrate powder in a fixed magnetic field only forms a magnetic linkage, and the concentrate particles are relatively immovable, so it is impossible to scrub and precipitate the non-magnetic inclusions inside. When the power is turned off, the magnetic linkage disappears, and the concentrate powder continues to sink A part of the fine ore concentrate powder is discharged into the tailings with the rising water flow and the medium and fine-grained non-magnetic substances without magnetic field adsorption.

When coils 2, 4, and 6 are energized, the fine ore powder rotates 180° from the state in the previous magnetic field cycle to form a flux linkage again. The energization intervals of the two sets of coils are different due to the different sorting environments, and the approximate range is 1 Between -6 seconds, while the magnetic rolling effect is realized repeatedly, the interval non-magnetic window period also causes a large amount of fine ore concentrate powder to be thrown into the tailings, resulting in a waste of a lot of resources

Due to the difference in ore properties, the emphases of ore dressing are different, and the elutriation machine must have a large magnetic field adjustment range and matching tumbling times and scrubbing functions. However, the traditional DC electromagnetic elutriation machine The adjustment range of the magnetic field is narrow, it does not have the function of scrubbing, and it cannot meet the ore separation requirements with huge differences, resulting in the beneficiation indicators failing to meet customer requirements

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