RU2321460C1 - Centrifugal vibratory concentrator - Google Patents

Abstract

FIELD: mining industry; gravity concentration.

SUBSTANCE: invention is designed for separation of precious metals and other heavy valuable minerals. Proposed device contains working chamber in form of conical bowl with entrapping coating in form of ring rifles on its inner surface made to helical single-start or multistart line. Through hole is made in interrifle groove of final turn. Inertia unbalance vibrator is made in form of two similar kinematics independent devices carrying unbalanced rotor with intersection axes of rotation. Each rotor contains its own motor being flexibly coupled with motor dynamically by lobe coupling. Housing is installed on support through elastic shock absorbers. Mounted on said support are charging and discharge device and concentrate receiver.

EFFECT: improved efficiency of operation of centrifugal vibratory concentrator owing to uninterrupted process of concentration without stopping to discharge concentrate.

2 cl, 3 dwg

Description

The invention relates to the field of mining and processing technology, in particular to a device for separating particles by specific gravity, and can be used for gravitational enrichment of placers and ores of ferrous, non-ferrous, rare and noble metals.

It is known that the centrifugal method of mineral processing is a progressive, environmentally friendly and most effective method for the gravity concentration of fine-grained pulps (placers or crushed ores) containing small and thin classes of heavy valuable metals. In Russia and abroad, this method is widely used in the gold mining industry, where in the processing of sands of placers and ores containing precious metals (gold, platinum, silver), centrifugal devices (concentrators, separators) of various designs, differing in the way of separation, are used in the beneficiation schemes (loosening) pulp material and the formation of concentrate [1].

In the general case, these devices include a working body rotating from the drive, made in the form of a cone-shaped bowl with a catching coating on its inner surface, most often in the form of annular arrays, feeding and unloading devices.

The known disadvantages of these devices include the periodic principle of their operation, due to the fact that the power is turned off for unloading the obtained concentrate, the device is stopped (or the bowl rotation speed is sharply reduced), and the concentrate is washed out of the annular grooves manually or using special irrigation systems.

However, this principle of operation is acceptable only for the concentration of poor ores or placers of precious metals containing less than 1-2 g / t of gold, silver or platinum, when the accumulation cycle of the concentrate is from 20 minutes to 2 hours.

In the concentration of polymetallic ores (tin, copper, zinc, tungsten, titanium zirconium), as well as iron ores, where the content of heavy valuable components can reach 0.5% or more, the concentrate accumulation cycle is from 3 to 10 minutes. In this regard, the productivity of the enrichment process due to frequent stops for unloading of the concentrate is sharply reduced and the use of centrifugal apparatus of periodic action becomes ineffective.

The closest applications for enrichment of such raw materials are centrifugal concentrators with constant (continuous) discharge of the concentrate of Canadian firms Knelson Concentrators (model KC-CVD) and Falcon Concentrators (model C) [2].

These hubs are structurally similar to each other. Their working body is a smooth conical bowl lined vertically in the bearing unit with a wear-resistant material inside, having a concentrate receiver in the upper part, equipped with a system of automatic valves and exhaust nozzles. In Knelson concentrators, the concentrate receiver has two cylindrical chambers sequentially installed along the pulp, one of which (the first) is used to collect the richest part of the concentrate, the other for the poor concentrate. In Falcon concentrators, the concentrate receiver has one chamber. The output of the concentrate in the known continuous apparatus is controlled by an automatic control unit by sequentially opening the valves at regular intervals.

The main disadvantages of the Knelson and Falcon continuous concentrators, sharply limiting their use, are:

- low extraction of fine grades of fineness (-100 μm) of the heavy fraction into a concentrate, which does not allow their efficient use in the enrichment of flotation products and stale tailings of polymetallic and iron ore GOKs for the extraction of minerals containing iron, tin, tungsten, titanium, chromium, etc. ;

(The low extraction of thin classes of heavy minerals is due to the short time spent by the enriched material on the collecting surface of the bowl, which has a low coefficient of friction between itself and the pulp, which does not create favorable conditions for the rapid separation of the pulp material in density).

- the complexity of the design and insufficient reliability of the valve system and exhaust nozzles, constantly working in contact with an abrasive medium (feed density up to 45% of the crushed ore), which causes their increased wear and, as a result, a decrease in the quality of the concentrate (increase in its output) and process performance enrichment due to downtime;

- excessively high cost of concentrators, exceeding the cost of concentrators of periodic action of a similar size by 3.5-4 times.

The constructions of domestic continuous concentrators known from the literature and patent sources have a common drawback: a large yield of low-grade concentrate due to the use of a large number of slotted discharge windows (channels) in the bowls and low extraction of small and thin classes of heavy minerals due to the low intensity of the process of separation of the mineral mixture in a rotating bowl (lack of mechanical or hydraulic loosening of the mineral mixture on the surface of the bowl) [1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15].

In this regard, at present, in the mining and geological industry of Russia, practically no domestic continuous concentrator is practically used.

Closest to the proposed technical solution is a centrifugal-vibration concentrator, including a working chamber in the form of a conical bowl with a catching coating in the form of annular arches on its inner surface, driven by a drive mechanism to rotate around a vertical axis, an inertial unbalanced vibrator and a housing mounted on a support by elastic shock absorbers, while the vibrator is located in the plane of the center of gravity of the concentrator, as well as loading and unloading devices [16].

This concentrator, due to the possibility of adjusting the magnitude of the amplitude and frequency of the bowl’s oscillations, regardless of its rotation frequency, makes it possible to select the optimal enrichment regime for fine-grained pulp depending on its mineral composition in order to achieve maximum recovery of the heavy useful component. However, the periodic mode of operation of such a concentrator, determined by the accumulation time of the concentrate in the inter-ring annular grooves of the bowl, does not allow its effective use in gold-sulphide, polymetallic, and iron ore mineral processing schemes because of the need to stop the power supply circuit and the concentrator itself for the period of concentrate unloading.

The objective of the present invention is to increase the efficiency of a centrifugal vibration concentrator.

The problem is solved by achieving a technical result, which consists in increasing the productivity of the apparatus by creating conditions for the continuous withdrawal of concentrate from the grooves of the bowl, without stopping the initial supply.

The specified technical result according to the invention is achieved by the fact that in a centrifugal vibration concentrator containing a working chamber in the form of a conical bowl with a trapping coating in the form of annular arches on its inner surface, driven by a drive mechanism, an inertial unbalanced vibrator and a housing, mounted on elastic shock absorbers on a support, loading and unloading devices and a concentrate receiver, the vibrator is made in the form of two identical kinematics There are several independent from each other devices carrying unbalanced rotors, the rotation axes of which are crossed, each of the rotors having its own engine mounted on a support and having an elastic dynamic connection with it, for example, in the form of a petal clutch. In addition, the annular arrays of the catching surface of the working chamber of this concentrator are made along a single screw or multi-thread line, while in the inter-groove groove of its final (upper) turn there is a through hole for the output of the concentrate, the dimensions of which are performed from the ratio

l = kb

where l is the length of the hole in the direction of the helix, mm;

b is the width of the hole equal to or close to the width of the inter-groove groove, mm;

k is the reduction coefficient equal to 1-3.

A comparative analysis of the proposed technical solution with the prototype shows the presence in it of significant features that distinguish it from the prototype, which allows us to conclude that the claimed technical solution meets the criterion of "novelty."

Thanks to the proposed design of the inertial unbalanced vibrator during its operation, the centrifugal concentrator body and the bowl-shaped working chamber mounted on it with its rotation drive experience vertical and torsional horizontal vibrations, which together provide helical oscillatory movements. When performing circular arrays of the catching surface of the working chamber along a helical line with a through hole on the final turn of the inter-groove groove, a concentrate of heavy minerals formed in the grooves during the operation of the concentrator due to torsional vibrations directed along the circumference with simultaneous tossing moves upward along the helical grooves to the hole and is continuously unloaded.

Due to the fact that the helical grooves can be made in the form of a single-start or multi-start line, an optimal degree of reduction of the concentrate is achieved depending on the content of the heavy useful component in the enriched raw material.

Proposed according to the invention, the ratio of the sizes of the discharge opening of the working chamber ensures, during the operation of the concentrator, the continuous unloading of the heavy fraction from the inter-groove grooves in the size range of the material being enriched from 0.1 to 3 mm

Thus, the set of essential features ensures the implementation of the objectives of the invention, while the possibility of achieving a technical result does not follow from the prior art, which allows us to conclude that the claimed technical solution meets the criterion of "inventive step".

Figure 1 schematically shows a General view (longitudinal section) of a centrifugal vibration concentrator; figure 2 is a section aa in figure 1; figure 3 is a section bB in figure 1.

The concentrator consists of a working chamber 1, built into the bearing assembly 2, mounted on the housing 3, on which the rotational drive 4 of the chamber and the inertial unbalanced vibrator 5 are fixed. The housing 3 is mounted with elastic shock absorbers 6 on the support 7, on which the loading (for pulp) is mounted ) 8 and discharge for tails) 9 devices and concentrate receiver 10.

The working chamber 1 is made in the form of a conical bowl, the inner surface of which has a trapping coating 11 in the form of annular arrivals made on a single or multiple helical line, while in the inter-groove groove 12 of its final (upper) turn there is a through hole 13 for outputting the concentrate.

The inertial unbalanced vibrator 5 is made in the form of two identical kinematically independent from each other devices 14, bearing unbalanced rotors 15, the axis of rotation of which are crossed, while each of the rotors is equipped with its own engine 16 mounted on the support 7, and has an elastic dynamic connection with it, for example, in the form of a petal clutch 17.

The hub works as follows. The electric drive 4 for rotating the working chamber 1 through the V-belt drive is sequentially started, and then the electric motors 16 of two kinematic devices 14, which through the flap couplings 17 inform the rotation of the unbalanced (unbalanced) rotors 15. The Mach moments resulting from the rotation of each rotor 15 due to their action in intersecting planes and due to the displacement of the attachment points of the rotors relative to the axis of rotation of the working chamber 1 create a housing 3 and all mounted on it elements 1, 2, 4 inclined torsional vibrations, which is facilitated by the installation of the housing 3 on the support 7 using elastic (elastic) shock absorbers 6. Then, through the loading device 8, for example, a gold-sulfide pulp of the required density is fed to the bottom of the chamber 1, which is twisted and discarded by rotating blades fixed to the bottom to the periphery of the camera. Under the action of centrifugal acceleration, solid pulp particles fall into the inter-grooves of the capture coating 11 of the working chamber 1, where as a result of intense directed vibrations, the material is loosened and particles of heavy minerals and gold sulfides are segregated inside the formed mineral “bed” with their concentration mainly at the chamber wall 1. Due to the torsional vibrations around the circumference with simultaneous tossing, the material slowly moves up the helical grooves, repeatedly peeling and freeing waiting for light mineral particles to form a concentrate. At the last turn, the concentrate is continuously discharged through the through hole 13 under the action of centrifugal force from the chamber 1 to the concentrate receiver 10 and then by gravity to the receiving tank (not shown in the drawing).

The light pulp fraction (tailings), being carried away by the vertical component of centrifugal force, rolls upward through the riffles and carried over the edge from the working chamber 1 to the unloading device 9 and then to the tailing dump.

Thus, the centrifugal enrichment process occurs in a continuous mode, without stopping the concentrator to unload the concentrate.

To provide more efficient enrichment of pulp with different material and particle size distribution of the solid phase, higher extraction of small and thin classes of valuable heavy minerals (polymetals and noble metals), the concentrator can be configured to achieve the most optimal modes by changing the amplitude and frequency of torsional vibrations. In this case, the change in the amplitude of the oscillations is provided by the change in the flywheel of the rotating unbalanced rotors 15 (the higher the moment, the greater the amplitude). The selection of the mass of rotor unbalances determines the necessary flywheel moment. The change in the frequency of torsional vibrations is provided by a change in the frequency of the electric current supplying the electric motors 16, the rotating rotors 15, for example, using known frequency converters.

According to the structural scheme of a centrifugal vibration concentrator described above, under the guidance of the authors, its current model (a reduced version of an industrial concentrator) is developed, manufactured and is currently being tested.

The hub has the following parameters:

The largest inner diameter of the working chamber (on the ring upper arrays), mm 165 Depth of the working chamber, mm one hundred The number of visits spiral helix one Dimensions of the discharge opening, l × b, mm 16 × 8 The frequency of rotation of the working chamber, rpm 650 The frequency of torsional vibrations, min ^-1 2820 Amplitude of torsional vibrations, mm 2,5 Installed power drive motor rotation of the working chamber, kW 0.37 Installed power engine torsional vibration drives, kW 2 × 0.09 Overall dimensions, L × W × H, mm 610 × 575 × 790

The tests were carried out on an artificial mixture of quartz sand with a particle size of <2 mm and granular martite with a particle size of <0.5 mm (content 10%), which, to a first approximation, imitates the tails of the Lebedinsky iron ore mining and processing complex of the Kursk magnetic anomaly.

The material was supplied in the form of pulp with a ratio of solid to liquid from 1: 4 to 1: 6 with a capacity of 800 kg / h and 1000 kg / h on solid.

The extraction of iron in the concentrate amounted to: in the first case, 91%; in the second case, 87% with a concentrate yield of ~ 13%, which is significantly higher than in iron ore enrichment at foreign centrifugal concentrators [17].

Concentrators of various sizes, manufactured according to the proposed technical solution, can find wide application:

- in the laboratory practice of geological exploration for mineralogical and technological research of mineral raw materials containing more than 0.3% of heavy valuable components (polymetallic, iron and gold-sulfide ores);

- during the development of enrichment technologies and industrial processing of these ores and their tailings.

Information sources

1. Lopatin AG, Centrifugal beneficiation of ores and sands. - M .: Nedra, 1987, p. 167-176.

2. Brochures (leaflets) of Canadian firms Knelson Concentrators (19855-98 Avenue, Langley, BC Canada V1M 2 × 5), (Email: knelson@knelson.com) and Falcon Concentrators (9663-199A Street, Langley , British Columbia, Canada V1M 2 × 7), (Email: falcon@concentrators.net) to centrifugal gravity concentrators.

3. Copyright certificate of the USSR No. 724192, Cl. B03B 5/32, 10.20.78.

4. Copyright certificate of the USSR No. 845848, Cl. B03B 5/32, 12/10/79.

5. Copyright certificate of the USSR No. 897294, Cl. B03B 5/32, 10.20.78.

6. Copyright certificate of the USSR No. 919745, Cl. B03B 5/32, 06/27/80.

7. RF patent No. 2026745 C1, Cl. B03B 5/32, 08/18/92.

8. RF patent No. 2094122 C1, Cl. B03B 5/32, 10.27.97.

9. RF patent No. 2094123 C1, Cl. B03B 5/32, 10.27.97.

10. RF patent No. 2094124 C1, Cl. B03B 5/32, 10.27.97.

11. RF patent No. 2101090 C1, Cl. B03B 5/32, 05/21/96.

12. RF patent No. 2104790 C1, Cl. B03B 5/32, 05/17/96.

13. RF patent No. 2123884 C1, Cl. B03B 5/32, 02.20.98.

14. RF patent No. 2151006 C1, Cl. B03B 5/32, 06/29/99.

15. RF patent No. 2159680 C1, Cl. B03B 5/32, 11/27/2000.

16. RF patent No. 2220772 C1, Cl. B03B 5/32, 04.24.2002.

17. Enbaev I.A., Rudnev B.P., Shamin A.A., Kachevsky A.N. Processing of tailings of factories and unconventional raw materials using effective enrichment processes. - M .: 1998, p. 49-51.

Claims (2)

1. A centrifugal-vibration concentrator containing a working chamber in the form of a conical bowl with a trapping coating in the form of annular ripples on its inner surface, a drive mechanism for rotating the working chamber around a vertical axis, an inertial unbalanced vibrator and a housing mounted on elastic shock absorbers on a support, a loading and unloading device and concentrate receiver, characterized in that the vibrator is made in the form of two identical kinematically independent from each other devices, bearing unbalanced rotors, the rotation axes of which are crossed, and each of the rotors is equipped with its own motor mounted on a support and has an elastic dynamic connection with it, for example, in the form of a petal clutch, and the ring arrays of the catching coating of the working chamber are made on a single or multiple helical line, while in the inter-groove groove of the final (upper) of its turn there is a through hole for the output of the concentrate. 2. The centrifugal vibration concentrator according to claim 1, characterized in that the hole for withdrawing the concentrate from the inter-grooves of the catching coating of the working chamber is made from the ratio l = kb where l is the length of the hole in the direction of the helix, mm; b is the width of the hole equal to or close to the width of the inter-groove groove, mm; k is the reduction coefficient equal to 1-3.

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