RU2356650C2 - Method of dry concentration of ore - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention refers to extraction and concentration of minerals directly on site of deposit, particularly to primary processing of dry diamond containing raw material. The method of dry concentration of ore, for example diamond containing kimberlitic ore, consists in disintegration of source ore, in disintegration of field products, in sizing crushed kimberlitic source ore, in sizing field products, in their successive concentration to separate grades of size with preliminary pneumatic sizing of fine field product and in aspiration. Disintegration of source ore and disintegration of field products are performed in two-stage crushing of each one. Oversize fraction of sizing of crushed source ore of the first stage of crushing is directed to the second stage of source ore crushing. Oversize fraction of field product sizing is directed to the second stage of field product crushing, while rejects of coarse and medium size grades are directed to the first, and then to the second stage of field products crushing. The second stage of source ore crushing and the second stage of field products crushing are carried out by means of an impact crusher, for example rotor ones, while the first stage of field products crushing is performed by means of crusher of three-dimensional compression, for example a roller-press.

EFFECT: reduction of volume of material supplied to finish operations, increased efficiency of material processing and also increased efficiency of development of deposit with low contents of useful component.

2 cl, 2 dwg

Description

The invention relates to the field of extraction and mineral processing directly at the deposit, in particular to the primary processing of dry diamond-containing raw materials.

Known methods for implementing technological schemes for the beneficiation of diamond-bearing ores are ore-dressing plants where the primary concentration of diamond-containing raw materials and the extraction of diamonds occur. Typically, technological complexes include the following steps: disintegration of the feedstock, production of primary industrial concentrates, subsequent refinement of industrial concentrates, i.e. diamond extraction. At each stage, a wide variety of technological equipment is used for processing diamond-containing raw materials using a large amount of water (V.I. Bragin, I.I. Bragin. Technology of coal and non-metallic minerals. - Krasnoyarsk: Book Publishing House, 1973. - P.88- one hundred).

A common disadvantage of the known methods for implementing technological schemes is that it excludes the possibility of concentration of diamond-containing raw materials directly in the field. This, in turn, leads to an increase in the cost of enrichment due to the cost of transportation costs, water circulation systems, electricity and the creation of storage facilities for enrichment waste, i.e. all taken together makes industrial development of individual deposits unprofitable, especially those characterized by a low diamond content.

A known method for the extraction of diamonds from diamond-containing raw materials directly at the place of extraction (RF patent No. 2094126, B03B 7/00, publ. BI No. 30, 1997), including the disintegration of raw materials, classification of disintegrated raw materials by size classes, primary enrichment of classified raw materials, the disintegration of the resulting industrial products using self-grinding planetary mills and / or roller presses and subsequent refinement.

However, this method cannot provide a sufficiently effective processing of dry diamond-containing raw materials due to the inability to provide the necessary environmental safety when processing small productive material. In addition, the process of disintegration in a planetary mill and in a roller press is accompanied by the formation of ore agglomerates, and at freezing temperatures, frozen agglomerates that require additional equipment to destroy them.

A known method of dry concentration of diamond-containing kimberlite ore directly at the mining site, implemented in the complex according to the patent of Russian Federation No. 227607 (B07B 9/00, publ. BI No. 7, 2005), including the disintegration of the original ore with a grain size of 500 mm, the classification of disintegrated ore and industrial products , disintegration of industrial products with their return to classification, classification of sub-sieve industrial products into three size classes (-30 + 10 mm, -10 + 5 mm, -5 + 0 mm), separate enrichment of each intermediate in the enrichment modules in the form of X-ray fluorescence separators Hur, the tail of a large module product enrichment with oversize middlings classification module disintegrated initial ore and industrial products supplied to disintegration, and fine middlings before enrichment supplied to pnevmoklassifikatsiyu, unproductive product which is directed to the aspiration.

However, this method cannot provide effective processing of dry diamond-containing raw materials due to the use of crushing and grinding equipment for the disintegration of industrial products, which is simultaneously used to disintegrate the initial ore and whose operation at low temperatures is accompanied by the formation of frozen agglomerates that require additional equipment to destroy these agglomerates. In addition, the above method cannot be used for processing the original ore with a grain size of -1200 + 0 mm, which significantly limits the scope of its application.

The technical result of the invention is to increase the efficiency of ore processing (in particular, diamond-containing ore) through the use of more efficient equipment for disintegration, increasing the upper limit of disintegration of the original ore, reducing the amount of material supplied for further processing, ensuring the preservation of the useful component (diamond crystals) in industrial product disintegration processes.

The specified technical result is achieved by the fact that when implementing the method of dry concentration of ore, for example, diamond-containing kimberlite ore, the initial ore is disintegrated, the crushed initial ore is classified, the industrial products are classified, and their further enriched according to separate size classes with preliminary pneumatic classification of the small industrial product, aspiration, while initial ore disintegration and industrial products disintegration are carried out by two-stage crushing each, to the second stage of crushing The initial ore is sent to the oversize product of the classification of the crushed initial ore of the first stage of crushing, the oversize product of the classification of industrial products is sent to the second stage of crushing (finishing) of the industrial products, and the tailings of the large and middle classes are sent to the first and then to the second stage of crushing (finishing) of the industrial products. In addition, the second stage of crushing of the initial ore and the second stage of crushing (finishing) of industrial products is carried out using impact crushers, for example rotary, and the first stage of crushing of industrial products is carried out using crushing and grinding equipment based on the principle of volumetric compression, for example a roller press.

Disintegration of the initial ore and disintegration of the intermediate products by two-stage crushing of each, sending to the second stage of crushing the initial ore of the oversize classification product of the crushed initial ore of the first stage of crushing, sending the oversize product of the classification of intermediate products to the second stage of crushing (finishing) of the industrial products, directing the tailings of large and medium classes to the first, and then to the second stage of crushing (finishing) of industrial products, as well as carrying out the second stage of crushing the initial ore and the second stage of crushing (finishing) of industrial products using impact crushers, such as rotary crushers, and the first stage of crushing industrial products using crushing and grinding equipment based on the principle of volumetric compression, for example using a roller press, are differences from the prototype and indicate the novelty of the proposed method.

All operations are carried out with dry raw materials, while the second stage of disintegration of the initial ore is carried out using crushers, which, in addition to their main purpose (crushing), allow to destroy the agglomerates formed during the operation of crushing and grinding equipment at low temperatures (in this case, in jaw crushers), those. using a impact crusher, for example a rotary impact crusher. The enrichment is carried out according to the technological classes: large (in the particular case -30 + 10 mm), medium (in the particular case -10 + 5 mm), small (in the particular case -5 + 1.6 mm).

The first stage of the disintegration of large (-30 + 10 mm) and medium (-10 + 5 mm) intermediate products is carried out using crushing and grinding equipment based on the principle of volume compression, for example using a roller press, since only in the process of volume compression can the necessary degree of preservation of diamond crystals in the process of their disclosure from the ore mass should be ensured; the second stage of the disintegration of industrial products is carried out using crushers, which, in addition to their main purpose (finishing), make it possible to destroy agglomerates formed during work in crushing and grinding equipment based on the principle of volumetric compression (in a particular case, in a roller press), i.e. using a impact crusher, for example a rotary impact crusher. In the case of diamond ores, the use of impact crushers in the present invention exclusively for the second stage of crushing (finishing) of industrial products allows preserving the natural integrity of diamond crystals during disintegration. On the other hand, in the present invention, targeted material regrinding in a closed cycle is provided with classification and enrichment, which makes it possible to extract all diamonds not disclosed during the initial crushing of the initial ore and to provide technological flexibility of the scheme.

When implementing the method, diamond enrichment can be carried out directly at the place of extraction of diamond-containing raw materials using a modular complex capable of working with dry raw materials with a grain size of -1200 + 0 mm without damaging the diamond crystals contained in it, while ensuring the necessary environmental cleanliness due to efficient dust deposition. There is no need to transport substandard feedstock to an enrichment plant, where there are water circulation systems and systems for the collection and storage of enrichment waste, the operation of which requires large costs for electricity and the creation of large water and tailings. In addition, this method will allow to obtain a product for further processing with a given particle size distribution and with diamond crystals without chips and other surface damage. All this allows us to say that the claimed invention corresponds to the inventive step, since due to this solution the desired technical result is achieved, namely, increasing the efficiency of ore processing.

The invention is illustrated in figures 1 and 2, which show the technological scheme of the proposed method and the circuit diagram of the apparatus for implementing the proposed method, respectively.

The method is as follows. The initial ore with a grain size of -1200 + 0 mm in a dry (frozen) state is subjected to large crushing (the first stage) in a jaw crusher to the maximum size of the second crushing stage. The crushed product of the first stage of crushing in order to isolate the product ready for enrichment is sent for preliminary classification by size of the upper enrichment limit (in the particular case of 30 mm). Oversize classification product (+30 mm) is sent to the second stage of crushing into a rotary impact crusher, the crushed product of which, together with the finished product of the first crushing stage (sub-sieve pre-classification product) is sent to the classification and dust collection operation. The dust emitted during dust collection is directed to the dust deposition operations obtained during the classification of industrial products (fraction with a fineness above the upper concentration limit, coarse fraction -30 + 10 mm, middle fraction -10 + 5 mm, fine fraction -5 mm), after pneumatic classification of the fraction -5 mm and class allocations of -5 + 1.6 mm are directed to subsequent operations. The pneumatic classification material -1.6 mm is sent to dust deposition operations. To extract diamonds disclosed during the process of disintegration of diamond-containing ore, industrial products of -30 + 10, -10 + 5, -5 + 1.6 mm are enriched with dry methods for concentration of the useful component, for example, on X-ray luminescent separators (RLS). Tailings of enrichment of industrial products with a particle size of 30 + 10, -10 + 5 mm are subject to refinement. The refinement is carried out in two stages - the first stage in the roller press, then the agglomerates formed during the volumetric compression in the roller press are sent to the second stage of the completion in the rotary impact mill, to which, in addition, the fraction is sent with a particle size above the upper enrichment limit (in in the particular case, the fraction +30 mm) from the operation of classification and dust collection of the initial ore and intermediate products, and the product of disintegration of the impact crusher is sent together with the product -30 mm and zintegrirovannym product of the second stage feed ore crushing and classification for dust removal, as shown in Figure 1.

The circuit diagram of the apparatus for implementing the method of dry concentration of ore with a fineness of -1200 + 0 mm, in particular diamond-containing kimberlite ore (Fig. 2), includes operations of the first stage of crushing (coarse crushing) of the initial ore I, preliminary classification of the disintegrated initial ore II, the second stage of crushing (medium crushing) of initial ore III, classification and dust collection IV, enrichment of large, medium and small intermediate products V, pneumatic classification of small intermediate products VI, aspiration of air released into the atmosphere VI I, the disintegration of tailing intermediate products of large and medium enrichment VIII, the completion of intermediate products IX, related by means of transportation.

At the first stage of disintegration of the initial ore I, ore is crushed with a particle size of 0-1200 mm to the maximum size of the second stage of crushing. The implementation of the first stage of crushing is carried out in a jaw crusher 3, the loading of which is carried out through the hopper 1 and the feeder 2. The product of the disintegration of the jaw crusher 3 is sent to the preliminary classification operation II (grate or inertial screen 5). The product of the preliminary classification operation II with fineness above the upper concentration limit (in a particular case more than 30 mm) is sent to the second stage of crushing of the initial ore (average crushing), and with a fineness of less than 30 mm - to the classification and dust collection operation IV. The second stage of the initial ore III disintegration includes crushing in a rotary impact mill 12 (medium crushing), the finished material of which is sent to the classification and dust collection IV, carried out on an inertial screen 6 with a dust collection system 13. The screen 6 is connected by means of transportation with enrichment operations of large and medium-sized intermediate V, with pneumatic classification of small intermediate VI and with the operation of the second stage of regrinding of intermediate IX in a rotary impact crusher 31, on which w except grain size of material over the upper limit of enrichment serves to break agglomerates roller press.

The enrichment operations of large, medium, and small industrial products of V for the primary enrichment of specific ore fractions (separation of diamonds from diamond ore) are carried out by enrichment methods that provide a dry concentration of the useful component, in particular for diamond ore, it is possible to use X-ray luminescent separators 15, 16, 17. Tail products of separators large industrial product 15 and medium industrial product 16 are sent for completion in a roller press 28, and separators of small industrial product 17 are sent to ōnusa gangue 22. Concentrates concentrating apparatus conveyor means 34a, 34b and 34c are sent to finishing, e.g., in stationary plant.

The sub-sieve product of 0-5 mm classification and dust collection operations IV is sent to the pneumatic classification of fine intermediate VI, designed to isolate unproductive material with a particle size of less than 1.6 mm from the particle size class 0-5 mm, the pneumatic classification module contains a cascade-gravity classifier 23, a deposition system dust in the form of a cyclone-precipitator 24 and is connected to the fan 25 by an air piping system through the suction operation VII, productive class -5 + 1.6 mm allocated to the pneumatic classification operation sent to fine industrial product separators 17, and the non-productive class -1.6 mm allocated during pneumatic classification is sent to waste rock cone 22.

Above the equipment where intense dust formation is possible, air ducts of the dust collection system 13 are installed for aspiration of the air discharged into the atmosphere and dust removal. The suction process VII is designed to clean the air released into the atmosphere during the dedusting of the air sent to the air from the cyclone-precipitator 24, contains a battery of cyclones 27 and an aerodynamic shutter 14, which is connected by a conveyor system 20, 21 to the waste rock cone 22. The operation of the suction equipment is ensured fan 25. Additional suction modules VII are designed to remove dusty air from ducts 13 from places of intense dust generation and purification of air released into the atmosphere using air ducts 13, VII nalogichny process and associated with the cone gangue 22 via aerodynamic valve 14 and conveyor system 20, 21.

Disintegration operations of industrial products VIII, IX for completing the recycling of intermediate products (tailings of enrichment of separators 15, 16) are carried out on a roller press of the first stage of completing industrial products 28, then in a rotary impact crusher 31 of the second stage of completing industrial products, to which, in addition, the material is sent fineness of the upper limit of enrichment with the operation of classification and dust collection IV.

Dry concentration of diamond ore is as follows. The initial ore with a particle size of 0-1200 mm enters the hopper 1, then through the feeder 2 to the first stage of crushing (large crushing). The coarse crushing product is fed to the preliminary classification operation of the initial ore 5, the sieve product (for example, +30 mm) of which enters the second stage of crushing in the impact rotor crusher 12, and the sub-sieve product (for example, -30 mm) goes to classification and dust collection IV on an inertial screen 6, where, in addition, the disintegrated product from the rotary impact crusher of the second stage of crushing the initial ore 12 and the disintegrated product of the second impact rotary crusher enters and disintegration of industrial products 31.

The over-sieve product of the screen 6 with a particle size greater than the upper enrichment limit (in the particular case +30 mm) is fed into a rotary impact crusher 31 to destroy agglomerates of the roller press and to finish the material with a particle size greater than the upper enrichment limit +30 mm.

The sub-sieve product of screen 6 (for example, -5 mm) is fed to pneumatic classification VI, where the cascade-gravity classifier 23 separates the productive class 1.6-5 mm, and the unproductive class -1.6 mm, after dust particles are separated from it in the cyclone precipitator 24, together with the material emitted during aspiration of dusty air on module VII (in the cyclone battery 27), is fed by a system of conveyors 20, 21 to the waste rock cone 22.

The intermediate product with a screening size 6 with a particle size of 10-30 mm is fed for enrichment to apparatuses that allow dry concentration of 15 (for example, X-ray luminescent separators), where the concentrate and tail product are separated, the latter is fed to the final product VIII in the roller press 28, and then to the second stage of the completion of the intermediate product IX into the rotary impact crusher 31 for the destruction of agglomerates of the roller press and the completion of the class +30 mm.

The intermediate product of screen 6 with a grain size of 5-10 mm is fed for primary enrichment to devices that allow dry enrichment of 16 (for example, X-ray luminescent separators), where the concentrate and tail product are separated, the latter is fed to the final product of intermediate VIII in roller press 28, and then to the second the stage of finishing the intermediate product IX into a rotary impact crusher 31 for breaking agglomerates of the roller press and finishing the class +30 mm.

Material with a particle size of 1.6-5 mm is sent to apparatuses that allow dry enrichment of the small intermediate product 17 (for example, X-ray luminescent separators), where concentrate and tailings are released. The tail product is fed to the waste rock cone 22.

Concentrates of enrichment of large, medium and small industrial products V, using the appropriate means of transportation 34a, 34b and 34c, are sent for finishing operations, for example, to a stationary processing plant, and the waste remains on the waste rock cone 22.

The use of the proposed complex will allow operations with dry raw materials at negative or positive temperatures, excluding condensate formation and moistening of raw materials, in particular diamond-containing ore; to carry out operations with dry raw materials directly at the deposit, which will allow to involve deposits distant from stationary processing plants in processing; when enriching diamond-containing ore, reduce the amount of material supplied for finishing operations, as well as obtain a product for further processing with a given particle size distribution and with diamond crystals without chips and other surface damage; increase the profitability of developing fields with a low content of useful component.

Claims (2)

1. The method of dry concentration of ore, for example diamond-containing kimberlite ore, including disintegration of the source ore, classification of crushed source ore, classification of industrial products, their subsequent enrichment according to separate size classes with preliminary pneumatic classification of small industrial product, aspiration, characterized in that the disintegration of the source ore and disintegration each of the industrial products is carried out by two-stage crushing, while the oversize product of cl assimilation of crushed initial ore of the first stage of crushing, the over-sizing product of classification of industrial products is sent to the second stage of crushing of industrial products, and tailings of the enrichment of large and middle classes are sent to the first and then to the second stage of crushing of industrial products. 2. The method according to claim 1, characterized in that the second stage of crushing the initial ore and the second stage of crushing of the intermediate products are carried out using impact crushers, for example rotary, and the first stage of crushing of the intermediate products is carried out using volume crushers, for example a roller press.

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