Air-dry sand coal dressing system

Abstract

The invention discloses an air-dry sand coal dressing system. The air-dry sand coal dressing system is characterized by comprising a machine body, a sorting system, a coal discharging system, a ganguedischarging system, a medium treatment system, an electronic control system, a dust removal system and an auxiliary system, wherein the sorting system, the coal discharging system, the gangue discharging system and the medium treatment system are all located in the machine body, the coal discharging system and the gangue discharging system are correspondingly coordinated with a coal briquette layer and a gangue layer on the sorting system for use, a discharge port in the coal discharging system and a discharge port in the gangue discharging system communicate with a feed port in the medium treatment system, a discharge port in the medium treatment system communicates with a feed port in the sorting system, a dust removal port of the dust removal system communicates with the machine body,and a discharge port in the auxiliary system is connected to the feed port in the sorting system. Compared with the prior art, the air-dry sand coal dressing system has the advantages that water-method coal dressing and combined type air classification can be completed replaced, the coal dressing cost is effectively lowered, and the coal dressing efficiency is greatly improved.

Description

technical field [0001] The invention relates to the technical field of coal separation, in particular to an air dry sand coal separation system. Background technique [0002] China is a large coal-producing country. With the rapid development of the coal industry and the continuous improvement of the level of coal mining mechanization, the quality of raw coal has been declining. High requirements, unsorted raw coal cannot be used, so coal preparation has become an indispensable and important link in the process of coal production and utilization. The essence of raw coal sorting is to use the difference in physical and chemical properties of coal and other minerals to mechanically remove impurities in raw coal, such as gangue, pyrite, etc., and divide raw coal into clean coal products of different quality specifications. [0003] With the development of the coal preparation industry, the separation process of raw coal can be divided into two types: water separation and dry s...

AI Technical Summary

Problems solved by technology

[0005] 1. Coal preparation must use water and consume water. The average water consumption for processing 1 ton of raw coal is 0.2m 3 At most, 3 tons of water will be used, but the geological structure and geographical location of the mining area doom the lack of water sources. Even in the non-coal producing areas on the earth, more than 1 / 5 of the areas are seriously short of water, and the natural water sources cannot meet the needs of coal preparation. , or manually transfer water, or transport the raw coal to a place with sufficient water for centralized sorting, which is costly and inconvenient to operate

[0006] 2. The outflow of coal slime sewage not only causes coal loss, but also seriously pollutes the environment, leading to problems such as soil compaction. In order to reduce the large amount of coal slime sewage discharged outside, it is necessary to realize the closed loop of washing water. In order to realize the closed loop of washing water, the sewage must be carried out Purification treatment, for which special sewage purification system equipment must be attached, the cost is high and the coal preparation efficiency is reduced

[0007] 3. The moisture in the coal seriously affects or even determines the quality index of the product, and at the same time increases the ineffective transportation. In the winter transportation of wet coal in the alpine area, the phenomenon of freezing trucks will also occur. In order to reduce the moisture content of the selected products, a special special equipment must be attached Dehydration is carried out by dehydration machinery, but dehydration is only relative rather than absolute. As far as the current dehydration technology is concerned, the product after dehydration still contains a certain amount of water, which is not conducive to the direct utilization of coal.

[0008] 4. The separation is not thorough, there is gangue in the coal, and there is coal in the gangue. In the jigging coal preparation, because there is no clear interface between coal and gangue during the separation process, the separation is not thorough, and the comprehensive separation effect does not exceed 80%. The separation quality is low. The dense medium coal preparation technology in my country began in 1958. The coal preparation process is relatively complicated, the equipment and pipelines are easy to wear, the maintenance workload is heavy, and the requirements for operation and adjustment are stricter. The separation effect of suspension coal preparation is better, but the high medium consumption is still a major problem that plagues dense medium coal preparation in my country. In the practice of coal preparation, the medium consumption is about 1.5kg / t, which is a very good level Generally, the medium consumption of coal preparation plants is about 3kg / t, a little higher is 5-6kg / t, and some coal preparation plants have reached 10kg / t or even higher

[0009] 5. The coal preparation process is complicated and requires a large number of auxiliary machinery and equipment, which leads to huge investment in the construction or renovation of coal preparation plants, often tens of millions or even hundreds of millions of yuan

[0012] 1. The gangue discharge method is to use the scraper to push and scrape strongly, which causes the core components to be frequently blocked and damaged by gangue, coal slime and other debris and cannot work normally. After several improvements and other solutions, it still cannot meet the normal use requirements.

[0013] 2. The medium used is granular iron sand. The loss is too large, hundreds of tons per year. On the one hand, it increases the cost and wastes resources. On the other hand, when the iron sand is mixed with coal and burns at high temperature, it is easy to damage the boiler.

[0014] 3. The overall cost is too high and the production efficiency is low, which cannot realize industrial application

[0016] 1. Poor sorting effect: This method only belongs to the "bad coal elimination plate". As early as 1956, China developed shaking table sorting. It is only an improvement, because there is no clear interface between coal and gangue during the separation process, the bed surface becomes more and more vibrated and becomes a dead bed, the separation is not thorough, and the comprehensive separation effect does not exceed 75%.

[0017] 2. Low sorting efficiency

[0018] 3. The structure is complex and bulky, which leads to high production costs and large floor area. The volume of the processing capacity of 100 tons per hour exceeds 1,000 cubic meters, which leads to huge investment in new construction and renovation of coal preparation plants, which can easily cost millions or even tens of millions. Yuan

[0019] 4. High energy consumption, the system power of 100 tons / hour needs 300 kilowatts

[0020] 5. High production cost and high maintenance cost

[0021] 6. More dust, pollute the environment

[0023] 1. The massive and granular gangue still falls directly on the surface of the polyethylene plastic plate. Because the scraper is still used to push and scrape strongly, it will be blocked and worn quickly, resulting in failure to work normally.

[0024] 2. The manufacturing process is complicated, the manufacturing cost is too high, the structure is complicated, and the power consumption is huge, resulting in high cost of coal preparation, which is close to water separation

[0025] The above factors have led to the fact that dry coal preparation has not been able to achieve industrial application so far.

[0026] To sum up, because the existing dry coal preparation technology still has many immature problems, it is still not perfect, and it is only in the stage of exploration and trial, so it cannot be popularized and applied. At present, water separation is still the main method.

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