RU86495U1 - PLANT FOR ENRICHMENT AND SEPARATION OF GRAIN MATERIALS - Google Patents

Abstract

1. Installation for the enrichment and separation of granular materials, containing several classification sections located one above the other, characterized in that it contains two vibrating screens with two screening surfaces located in two tiers and equipped with a means for supplying washing liquid to the upper screening surface and storage bins for slurry, a vertical-type gravity hydroclassifier installed between vibrating screens and a sampling device for fine sand fractions (ZUMPF), output the accumulator hopper of the upper vibrating screen is hermetically connected to the inlet of the hydroclassifier, and the outlet of the lower accumulator hopper is connected to the sump, the hydroclassifier contains a cylindrical housing with nozzles for introducing the hydraulic mixture and washing liquid and nozzles for draining fine fractions and withdrawing the condensed product, the nozzle for introducing the hydraulic mixture with the angle of the hydraulic mixture is made taper 15-18 ° and is lowered into the hydroclassifier cavity along the central vertical axis to the level of 0.1 of the height of the cylindrical part of the housing, the pipe the water of the condensed product is made upright, plugged from below and connected to the means for supplying the washing liquid and to the transport pipeline for outputting the condensed product to a vibrating screen of the lower tier. ! 2. Installation according to claim 1, characterized in that the drain pipe is located in a cylindrical nozzle mounted concentrically to the housing at the inlet of the hydroclassifier and connected to the housing by a conical shell, the diameters of the nozzle and the cylindrical part of the housing are correlated as 1.0: 1.45, and the height of the nozzle does not exceed 1.2 of the diameter of the drain

Description

The utility model relates to devices for the enrichment and separation of granular materials and can be used in mining, construction and other industries for the processing of mineral raw materials and industrial waste.

A known installation is designed to enrich stone or gravel-sand material with a "wet" method and sort by fractions of large, medium and small, including wet and clay various materials, on vibrating screens such as GIL (light inertial screen) or GIS (average inertial screen) ) equipped with spray nozzles for supplying washing water to them. Moreover, the separation of the material occurs when it moves relative to the working surface of the screen, where the material is stratified into fractions gradually, with the release of particles larger than 5 mm and with the formation of pulp from the water and screenings of sand material. The water consumption for washing granular materials or crushing screenings at each vibrating screen depends on the amount of clay inclusions in the source material, the finished products in the form of crushed stone and sand from granular materials or screenings obtained at the wet enrichment plant are transported by conveyor belts to finished goods warehouses (Manual on enrichment of screenings of crushing and different-strength stone materials. Ministry of Transport Construction of the USSR. State All-Union Road Scientific Research Studio Institute "SOYUZDORNII").

The disadvantage of this technical solution is the complexity of separation and low efficiency of sieving by the "wet" method of particles of fractions of less than 5 mm, since one of the important factors affecting the efficiency of wet sieving of particles of fractions of less than 5 mm on screenes of the GIL or GIS type is the sieve power characteristic . Since particles smaller than the size of the separation must be carried out in the under-sieve space, the performance of the screen usually decreases with an increase in the proportion of such particles in the feed. Another important factor is the number of particles close in size to the separation class. Such particles in the starting material may be up to 50-60% of the total amount of the starting material. A small class, for example, of a larger separation makes it difficult to carry particles into the sublattice and, in some cases, leads to clogging of the nets. The small size class of a smaller separation size also impairs the screening efficiency of sand material. Since when the content of the particles of the under-sieve fractions in the starting material to be separated is greater than the estimated screening capacity of the sieve, the quality of the products obtained in the oversize space worsens due to the clogging of the product by particles of the under-sieve fractions.

Gravitational hydroclassifiers of the vertical type are known with the possibility of operation with gravity (gravity) feed of the initial slurry and with an upward flow of clean water, for the separation of natural and artificial sand materials according to a given boundary grain mainly with a size of less than 2-3 mm (from 1.25 to 0.16 mm) ( M.I.Khrustalev. “Best practices of sand enrichment”, M .; 1990, pp. 13-18).

Of all the currently known hydroclassifiers, vertical-type apparatuses provide the highest separation accuracy, however, the achieved separation accuracy of sand particles in such hydroclassifiers is lower than that which can be achieved by sifting sand material on vibrating screens. Since the most complete separation of sand materials, mainly with a size of less than 2-3 mm, using vertical hydroclassifiers, occurs only with the free movement of particles, with a volumetric solids content of less than 5%. And the pulp obtained after wet sieving, on screens of the GIL or GIS type on the upper tier, usually has a solid to liquid ratio T: L = 1: 2 ÷: 6, (sometimes T: L = 1: 8 ÷ 10). Therefore, the pulp entering the hydroclassifier for separation is processed with a decrease in the efficiency and quality of separation due to the tightness of particles in the separation process.

The closest in technical essence and the achieved result to the proposed utility model is a unit for the hydroclassification of granular materials, containing several classification sections placed on the support frame one below the other, each of which consists of a cylinder-conical tank with nozzles for entering the hydraulic mixture, washing water and the outlet of the condensed product and a drain chamber with overflow pipes for classification products from one section to another and equipped with hydraulic mixtures installed above the inlet pipes the upper section with a slotted hydraulic screen with an accumulating hydraulic mixture hopper, and the working surface of the hydraulic screen has a convex curvilinear shape with two screening surfaces. (RU No. 2168364, class B03B 5/62, B03B 7/00, publ. 06.10.2001).

The disadvantage of this technical solution is the design complexity, the decrease in the quality indicators of the particle size distribution of the isolated fractions due to the spread between the given percentage of “plus” and “minus” particles in them, due to the fact that hydroclassification occurs in a constrained mode.

The proposed utility model solves the problem of simplifying the design, and ensures the optimal efficiency of wet separation and enrichment of sand and gravel material of several fractions for particles smaller than 5 mm in vibrating screens such as GIL or GIS, taking into account the sieving performance of each sieve.

This problem is solved in that the installation for the enrichment and separation of granular materials, containing several classification sections located one above the other, according to the proposed utility model, contains two vibrating screens with two screening surfaces located in two tiers and equipped with a means for supplying washing liquid to the upper screening surface and accumulating bunkers for slurry, gravitational hydraulic classifier of vertical type, installed between vibrating screens, and intake the construction of small sand fractions (ZUMPF), the output of the accumulating hopper of the upper vibrating screen is hermetically connected to the inlet of the hydroclassifier, and the output of the lower accumulating hopper is connected to the sump, the hydroclassifier contains a cylindrical housing with nozzles for introducing the hydraulic mixture and washing liquid and nozzles for draining the fine fractions and , the nozzle for introducing the hydraulic mixture is made in the form of a diffuser with a taper angle of 15-18 ° and is lowered into the cavity of the hydroclassifier along the central vertical axis to the level of 0.1 the height of the cylindrical part of the body, the outlet pipe of the condensed product is made vertical, sealed from the bottom and connected to a means for supplying water and with a transport pipeline for outputting the condensed product to a vibrating screen of the lower tier.

At the same time, the drain pipe can be located in a cylindrical nozzle installed concentrically to the housing at the inlet of the hydroclassifier and connected to the housing by a conical shell; the diameters of the nozzle and the cylindrical part of the housing are related as 1.0: 1.45, the height of the nozzle does not exceed 1.2 the diameter of the drain pipe.

The diffuser from the outside at a level 2/3 of the height of the cylindrical part of the hydroclassifier case is enclosed by a cylindrical wall, which is connected to the lower end of the diffuser by an annular plate, and on top they are interconnected by a lid in the form of a truncated cone with a taper of at least 60 °.

The length of the pipe for withdrawing the condensed product from the hydroclassifier is 0.5 ÷ 0.8 of the height of the cylindrical part, and the pipe is connected to the means for supplying water at a level of 2/3 of the height, and with a transport pipeline for withdrawing the condensed product at the level of 1/3 of the height.

The transport pipeline for withdrawing the condensed product from the hydroclassifier has a U-shape, the upper part of which is located at the level of 0.7-0.95 of the cylindrical part of the hydroclassifier.

The accumulating hopper of the upper vibrating screen is equipped with a drain pipe for excess fluid.

The unit is also equipped with transport conveyors for moving sifting products from vibrating screens to storage sites.

The proposed design of the inlet pipe of the hydroclassifier allows you to maintain the constancy of the cross section of the cylindrical part (reception and separation chamber) of the hydroclassifier and create conditions for a smooth without vortex formation of the fluid mixture into the cavity of the reception and separation chamber and better classification by boundary size. Moreover, the angle of taper of the nozzle 15-18 ° is the most optimal for a smooth decrease in the rate of fall of particles in the hydraulic classifier (I.E. Idelchik. "Guide to hydraulic resistance, second ed., M;" Engineering ", 1975, section 4 , p. 119).

The specified parameters of the cylindrical nozzle of the hydroclassifier, the vertical pipe and the transport pipeline for withdrawing the condensed product from the hydroclassifier provide the optimal hydrodynamic mode of operation of the hydroclassifier.

Figure 1 presents a General view of the installation for the enrichment and separation of granular materials, figure 2 - hydroclassifier, figure 3 the same view A.

The proposed installation for the enrichment and separation of granular materials contains a feed unit for the source material 1 including a hopper 2 equipped with a vibrator 3, for regulating the supply of the source material and shut-off valve 4; two “wet” screening units located in two tiers and consisting of GIL or GIS vibrating screens with two screening surfaces. The upper vibrating screen contains two vibrating screens 5 and 6, one above the other, a transportation system in the form of conveyors 7 and 8, for storing the product from the upper screening stage into storage cones 9 and 10. Above the upper vibrating screen there is an irrigation system including a hydraulic pump 11 with a shut-off fittings 12, for pumping circulating water from the reservoir reservoir, through the water conduit 13 to the pipe 14, on which the spray 15 is installed (either nozzles, or transverse slotted slots are made). The water conduit is equipped with a control valve 16, a flow meter 17 for monitoring and regulating the supply of circulating water and shut-off valves 18.

Under sieves 5 and 6, there is an accumulating tank in the form of a pyramidal hopper 19, where a sand pulp (hydraulic mixture) 21 of particles passing through the lower sieve 6 and water coming from the irrigation system is formed. The hopper 19 is equipped with a drain pipe 20 connected to the overflow line of excess fluid in ZUMPF.

The hopper 19 through the vertical channel 22, is hermetically connected to the inlet pipe 24 of the gravitational hydroclassifier 23 of the vertical type. The hydroclassifier 23 comprises a cylindrical conical body, with a cylindrical nozzle 25 mounted concentrically to the cylindrical part 27 of the body, which are interconnected by a conical shell 26. The diameters of the nozzle and the cylindrical part of the body are related as 1.0: 1.45, and the height of the nozzle does not exceed 1.2 the diameter of the drain pipe. In the cylindrical nozzle 25, a drain pipe is installed, connected to the pipeline 39 for discharging a predetermined fine fraction of sand particles in ZUMPF.

The inlet pipe 24 has the shape of a diffuser with a taper angle of 15 ÷ 18 ° and is lowered into the hydroclassifier cavity along the central vertical axis to a level of 0.1 of the height of the cylindrical part 27. The diffuser from the outside at the level of 2/3 of the height of the cylindrical part 27 of the hydroclassifier case is enclosed by a cylindrical wall 28, which is connected to the lower end of the diffuser by an annular plate 29, and on top they are connected by a cover 30 in the form of a truncated cone with a taper of at least 60 °, preferably 120-150 °. The upper edge of the nozzle 25 on the inner side and the inlet pipe 24 on the outer side are hermetically connected to each other by an annular plate 31.

At the exit of the conical part 32 of the hydroclassifier 23, a vertical pipe 33 is installed to withdraw the condensed product from the hydroclassifier, which acts as a receiver, due to the design features. The length of the pipe 33 is equal to 0.5 ÷ 0.8 of the height of the cylindrical part of the hydraulic classifier, at a level 2/3 of its height, an inlet pipe 34 connected to the water conduit 13 with a control valve 35, a flow meter 36 is installed to control and regulate the supply of circulating water, and shutoff valves 37. The vertical pipe 33 itself is plugged from below by a flange plug 38, and at the level 1/3 of its height, a transport pipe 40 is connected to output the condensed product to a vibrating screen of the lower tier. The pipeline 40 has a U-shaped shape, the upper part of which is located at the level of 0.7-0.95 of the cylindrical part of the hydroclassifier, and ends with a tip 41 located above the upper sieve of the lower vibrating screen. The tip 41 is formed by two inclined plates - the bottom 42 and the top 43, having different slopes to the horizontal to form a hole G between them.

The vibrating screen of the lower tier contains an upper sieve 44 with a transport conveyor 45, for moving and storing the product from the sieve 44 into the storage cone 46, and a lower sieve 47 with a transport conveyor 48, for moving the product from the sieve 47 to the hopper 49 and subsequent packaging in soft containers fifty.

An accumulating hopper 51 is installed under the lower vibrating screen to collect particles of small fractions (<0.8 mm) that have passed through the lower sieve 47 together with water and move them to the ZUMPF.

The vibrating screen of the lower tier is also equipped with an irrigation system, including a nozzle 52 connected to a water conduit 13, on which the sprinklers 53 are located. On the nozzle 52 are also installed: a control valve 54, a flow meter 55 for controlling the supply of circulating water and shut-off valves 56.

The proposed installation for the enrichment and separation of granular materials works as follows:

Before turning the unit into operation, the initial material intended for enrichment and separation is initially analyzed, the particle size and chemical composition, the content of contaminants and smaller hardness varieties such as mica and other inclusions, strength, moisture, bulk density of the starting material are determined.

Preliminarily determine the necessary list of fractions for separation from the particle size distribution of the source material.

The screening capacity of each sieve installed on the vibrating screens of both stages of screening is determined.

Based on the particle size distribution of the source sand material determine the performance of its supply for enrichment and separation. Given the sieving performance of the sieves, also set the dosage of material from the hopper 2 by turning on one of the positions of the frequency controller on the vibrator 3.

In the initial state of the installation, the shut-off valve 4 on the hopper 2 and the shut-off valves - valves 12, 18, 37 and 56 are closed. The installation is included in the work in the following sequence:

- open the valve 12, then turn on the pump 11 for supplying circulating water to the system 13;

- open the valve 37 and regulate the flow of circulating water through the hydroclassifier 23 until a stable flow of circulating water through the transport pipeline 40;

- after the appearance of a stable flow of water from the pipeline 40 by the valve 37, a water supply is added through the pipe 34 until a stable flow at the outlet of the pipeline 39 to the ZUMPF appears;

- valve 37, through the flow meter 36 manually set the volume of circulating water to the calculated value for the hydroclassifier 23, fix and transfer the water supply on the control panel (not shown) to automatic control mode;

- after setting the pure water supply mode on the hydroclassifier 23, the valves 18 and 56 are opened, through the flow meters 17 and 55 manually set the volume of circulating water in accordance with the specified norms and switch the water supply on the control panel to automatic control mode;

- turn on the upper and lower vibrating screens, then open the shutter 4 and turn on the vibrator 3.

Installation for the enrichment and separation of granular materials is included in the work. The initial mixture enters the upper tier of screening.

From the particle size analysis of the starting material, fractions are determined that need to be distinguished, for example, particles of fractions of 5.0-2.0 mm, 2.0-1.2 mm, 1.2-0.8 mm and other fractions <0.8 mm send to ZUMPF.

To solve this problem, the following grids were installed on the screens:

- a mesh with 5.0 mm holes is installed on the upper screen of the upper vibrating screen

- a mesh with 2.0 mm holes is installed on the lower sieve of the upper vibrating screen

- a mesh with 1.2 mm holes is installed on the upper sieve of the lower tier

- a mesh with 0.8 mm holes is installed on the lower sieve of the lower tier. Screening capacity of sieves:

- with 5.0 mm holes - 54.45 t / h.

- with 2.0 mm holes - 28.26 t / h.

- with holes of 1.2 mm - 7.45 t / h.

- with 0.8 mm holes - 4.41 t / h.

In the first section of the classification (the upper sieve of the hydraulic screen of the upper tier), the sand mixture is pre-enriched. The initial sand mixture entering the upper sieve 5 is washed with water supplied from the water conduit 13 through the nozzle 14 to spray 15. The whole oversize product is large stone and sand and gravel material with a particle size of more than 5 mm, as well as knots, clay agglomerates and shell rock , removed from the sieve 5, moved to the conveyor 7 and transported to the storage cone 9. With the accumulation of a sufficient volume of large stone and sand and gravel material with a particle size of more than 5 mm, it is used as rubble building material.

Sandy material with particles from 5 mm and below falls through a sieve 5 into the second classification section (lower sieve of a hydraulic screen of the upper tier).

In the second classification section, in the process of screening, a sand fraction is obtained - a sublattice product sifted through the upper sieve 5 and remaining on the sieve 6 in the form of sand material with a particle size of 2-5 mm, which moves to the conveyor 8, and then to the storage cone 10, as a building material.

All sand material sifted through a sieve 6 enters with the hopper 19 together with water, where in the form of pulp 21 it accumulates in the outlet channel 22. The amount of water in the hopper 19 is monitored and, if the set level is exceeded, is discharged through line 20 to the ZUMPF.

The pulp 21 remaining in the hopper 19 through the channel 22 enters the third classification section - to the inlet pipe 24 of the hydroclassifier 23. The lower part of the pipe 24 in the form of a diffuser reduces the rate of fall of sand particles, and at the junction of the cylindrical and conical parts of the hydroclassifier 23 the connected particle stream is divided into small groups and single particles that slowly descend into the conical part. The oncoming flow of pure water supplied through the pipe 34 at a given speed for particles of the boundary size of the solid phase of the pulp 21 picks up particles smaller than the boundary size and carries them through the drain pipe 39 to the ZUMP. Particles equal to the boundary size and larger are lowered into the vertical pipe 33 and through the transport pipe 40 with the tip 41 are sent to the fourth classification section (laid out on the upper sieve 44 of the vibrating screen of the lower tier). On a sieve 44, an oversize product is obtained - a sand fraction of 1.2-2.0 mm. Moreover, the mass of sand material entering the sieve 44 corresponds to the screening capacity of this sieve and the amount of sieve product determined by analyzing the particle size distribution of the starting material, since the bulk of the excess particles was previously calculated when determining the feed rate of the starting material to the installation and removed through the hydroclassifier . The sandy material remaining on the sieve 44, a fraction of 1.2-2.0 mm, as a sieve product is transferred to the conveyor 45 and further to the storage cone 46.

Sandy material passing through the sieve 44 enters the fifth classification section (on the lower sieve 47 of the vibrating screen of the lower tier). On a sieve 47, a sand material of a fraction of 0.8-1.2 mm is obtained as a sieve, which moves from the sieve 47 to the conveyor 48 and then to the hopper 49 for filling the product in soft containers 50.

Small particles, fractions less than 0.8 mm, passed through a sieve 47 together with water fall into the hopper 51 and then into the ZUMPF.

The proposed installation allows you to effectively enrich and separate gravel and sand material in a "wet" way and improve the quality indicators of the range of fractions of the resulting material.

Claims (8)

1. Installation for the enrichment and separation of granular materials, containing several classification sections located one above the other, characterized in that it contains two vibrating screens with two screening surfaces located in two tiers and equipped with a means for supplying washing liquid to the upper screening surface and storage bins for slurry, a vertical-type gravity hydroclassifier installed between vibrating screens and a sampling device for fine sand fractions (ZUMPF), output the accumulator hopper of the upper vibrating screen is hermetically connected to the inlet of the hydroclassifier, and the outlet of the lower accumulator hopper is connected to the sump, the hydroclassifier contains a cylindrical housing with nozzles for introducing the hydraulic mixture and washing liquid and nozzles for draining fine fractions and withdrawing the condensed product, the nozzle for introducing the hydraulic mixture with the angle of the hydraulic mixture is made taper 15-18 ° and is lowered into the hydroclassifier cavity along the central vertical axis to the level of 0.1 of the height of the cylindrical part of the housing, the pipe the water of the condensed product is made upright, plugged from below and connected to the means for supplying the washing liquid and to the transport pipeline for outputting the condensed product to a vibrating screen of the lower tier. 2. The installation according to claim 1, characterized in that the drain pipe is located in a cylindrical nozzle installed at the inlet of the hydroclassifier concentrically to the housing and connected to the housing by a conical shell, the diameters of the nozzle and the cylindrical part of the housing are correlated as 1.0: 1.45, and the height of the nozzle does not exceed 1.2 diameters of the drain pipe. 3. Installation according to claim 1, characterized in that the diffuser on the outside at a level 2/3 of the height of the cylindrical part of the hydroclassifier housing is enclosed by a cylindrical wall that is connected to the lower end of the diffuser by an annular plate, and on top they are interconnected by a truncated cone lid with a taper of at least 60 °. 4. Installation according to claim 1, characterized in that the length of the pipe for withdrawing the condensed product from the hydroclassifier is 0.5 ÷ 0.8 of the height of the cylindrical part. 5. Installation according to claim 4, characterized in that the pipe for withdrawing the condensed product from the classifier is connected to means for supplying washing liquid at a level of 2/3 of the height, and with a transport pipeline at the level of 1/3 of the height. 6. Installation according to claim 1, characterized in that the transport pipeline for withdrawing the condensed product from the hydroclassifier has a U-shape, the upper part of which is located at the level of 0.7-0.95 of the cylindrical part of the hydroclassifier. 7. Installation according to claim 1, characterized in that the storage hopper of the upper vibrating screen is equipped with a drain pipe for excess fluid. 8. Installation according to claim 1, characterized in that it is equipped with transport conveyors for moving the sifting products from vibrating screens to storage locations.