Technique for recycling cleaned coal from low-value gangue or tail coal of coal washery

Abstract

The invention relates to a technique for recycling cleaned coal from low-value gangue or tail coal of a coal washery. The technique comprises the following steps of: crushing the gangue into powder with the grain size of 2mm, and dissociating coal from gangue mineral monomers; adding water into the powder or the tail coal of the coal washery to obtain ore pulp, carrying out reverse separation by virtue of a table concentrator, wherein light coal enters into a tailing slot to be prepared into a bed cleaned coal product, heavy gangue mineral enters into a concentrate slot to be prepared into gangue slag which can be used for making bricks, and an accretion body between the light coal and the heavy gangue mineral and a part of gangue mineral enter into a middling slot to be prepared into a bed midding coal product; screening the bed cleaned coal product to remove fine gangue component, dehydrating oversize products to obtain a final bed cleaned coal product; carrying out flotation separation on the bed middle coal product by adopting a flotation machine, and carrying out filter pressing on floating products to obtain a floating cleaned coal product, wherein a sink product is the gangue slag used for making bricks. By applying the technique provided by the invention, cleaned coal in the tail coal or gangue can be economically and reasonably recycled in a large scale, the reverse separation by using table concentrator is organically combined with certain flotation and the like, thus technological adaptability is high and technical index is good; coal gangue with ash content up to 62-72% can be processed into cleaned coal or secondary cleaned coal with the ash content of 27-40% only, technological process is simple and compact, operation cost is low, net profit created by each ton of the coal gangue is 50-80 yuan, no 'three wastes' pollution is produced, and the technique provided by the invention is safe and environmentally friendly.

Description

technical field [0001] The invention relates to a technology for resource utilization of solid waste, and a process for recovering clean coal from low-value gangue or tailing coal of a coal washing plant. Background technique [0002] Existing coal washing plants carry out dense medium treatment on the raw coal lumps from coal mines and discard the coal gangue directly, and put it in the mountain depression to form a large rock dump. Because gangue also contains certain coal quality, this method of handling gangue is equal to wasting useful resources in vain. People have been trying various methods for the utilization of this gangue all the time, but because the coal quality of gangue is small, the extraction cost is high and it was abandoned halfway, no one cares about it for a long time. It was not until the 1980s that people began to put the use of gangue on the agenda again. At that time, it was mainly used as a raw material for making bricks. Because there was a certa...

AI Technical Summary

Problems solved by technology

But so far there has not been a kind of process that can be directly used in industrial production, which can treat coal gangue economically and efficiently, turn waste into treasure, and have no pollution and no waste discharge.

This technique has not been reported so far

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