Floatation tailings coal slime gradient reduction process

Abstract

The invention discloses a floatation tailings coal gradient reduction recovery process. The process comprises the steps that floatation tailings coal is continuously added into a first-stage high-efficiency concentrator, first-grade concentrated underflow is uniformly blended with FBS tailings coal, and first-stage high-efficiency concentrator overflow is conveyed to a second-stage concentrator through a pipeline; the first-grade concentrated underflow blended with the FBS tailings coal enters a FBS tailings dewatering screen for dehydration treatment, then medium matter on the screen is conveyed to a first centrifugal machine through a pipeline and treated to obtain a middlings coal product, water under the screen and centrifugate of the first centrifugal machine are conveyed to a middlings coal and gangue classifying cyclone through a pipeline and are sorted, and sorted underflow is conveyed to a coarse slime dewatering screen and dehydrated to obtain a middlings coal product; and achemical is added into a second-stage concentrator, first-stage high-efficiency concentrator overflow and middlings coal and gangue classifying cyclone overflow are conveyed to the second-stage concentrator through pipelines, second-grade concentrating is performed, and second-grade concentrated underflow enters a concentration classifying cyclone, so that third-grade concentrating is performed. According to the floatation tailings coal gradient reduction recovery process provided by the invention, the floatation tailings coal is subjected to multi-stage gradient concentrating, the coal slimeamount is gradually decreased, and the feeding amounts of the filter pressing and drying links are decreased.

Description

technical field [0001] The invention relates to the technical field of recovery of flotation tailings, in particular to a process for recovery of flotation tailings by step reduction. Background technique [0002] Coal slime is a by-product produced during the washing process of the coal preparation plant. Its main component is the tailing coal produced by the flotation operation. The particle size is 0-0.5mm, and the ash content is generally between 45%-60%. With the improvement of mining mechanization and the continuous decline of raw coal properties, the amount of slime produced in the coal washing process has increased, and the treatment of flotation tailings has become a difficult point for various coal preparation plants. The coal slime treatment link often becomes the key factor that the coal slime water treatment process does not meet the production demand, resulting in the accumulation of coal slime in the circulating water, a vicious circle, and restricting product...

AI Technical Summary

Problems solved by technology

[0004] In actual production, due to problems such as the overflow of the grading cyclone and the wear and tear of the curved screen and the centrifuge screen, some coarse slime enters the fine slime system, and the amount of slime will inevitably increase.

Secondly, although the filter press is a special equipment for recovering fine-grained coal slime, its stand-alone processing capacity is small, and the filter cake after filter press dehydration has high moisture content, is easy to stick into agglomerates, and has poor looseness, so it cannot be directly mixed into medium coal.

Then, according to the requirements of environmental protection policy, the amount of air dust emission limits the drying treatment of coal slime

In addition, due to the gradual scarcity of natural gas resources, the limited use of natural gas in certain periods of time by production enterprises, and the high price of natural gas, the drying and processing capacity of coal slime has been severely restricted. If the amount of coal slime to be dried is large, the production cost of the enterprise will inevitably increase

[0005] In summary, the lack of coal slime water treatment system, which is a key process of coal preparation plant, has seriously affected production and cannot meet the increasingly stringent environmental protection control. Necessary technical transformation is required to reduce the amount of coal slime that needs to be filtered and dried

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