RU76580U1 - CENTRIFUGAL-VIBRATION HUB - Google Patents

Abstract

The utility model relates to means of gravitational enrichment of minerals, in particular to devices called centrifugal concentrators, for separating free particles of noble metals and other heavy useful components (for example, polymetals) having a higher density relative to gangue, in the field of centrifugal forces of alternating directions and quantities. It can be used in the geological industry when conducting prospecting exploration for precious metals, as well as in the mining and processing industry, primarily in the development of deposits with fine and thin gold. The centrifugal vibration concentrator contains a working chamber in the form of a conical bowl with a friction shaft in its lower part and with a catching coating in the form of annular grooves on its inner surface, a camera rotation drive through a flexible tubular element that can deflect the camera from the vertical axis of rotation, its displacements in horizontal and vertical planes, a tilt angle limiter of the chamber, through which a friction shaft in contact with the internal friction limiter surface. The latter is mounted on elastic shock absorbers on the base coaxially with the drive mechanism. The hub has a loading and unloading device. The friction surfaces of the shaft and the limiter are cylindrical. The lower driven part of the shaft is equipped with a flywheel to balance the bending moment from the rotation of the working chamber and maintain a stable planetary vertical or close to vertical rotation of the chamber to ensure maximum extraction of the heavy useful component. In this case, the flywheel can be made in the form of a massive round clamp for connecting the friction shaft with a flexible element of the camera rotation drive mechanism. The technical result achieved is an increase in the efficiency of the centrifugal vibration concentrator due to stabilization of the enrichment modes on the entire collecting surface of the working chamber throughout the enrichment cycle.

Description

The utility model relates to technical means for gravitational enrichment of minerals, in particular to devices for separating free particles of noble metals and other heavy useful components (polymetals) having a higher density relative to waste rock in the field of centrifugal forces of alternating direction and magnitude. It can be widely used in the mining and processing industry for the extraction, first of all, of small (less than 0.25 mm) and thin (less than 0.1 mm) fineness grades of precious metals, for example gold from placer sands, ground ore, beneficiation tailings, rough concentrates.

It is known that the centrifugal method of mineral processing is a progressive, environmentally friendly and most effective method for the gravitational enrichment of fine-grained pulps containing micron size classes of heavy valuable components. In Russia and abroad, this method has been widely used in the gold mining industry, where in the processing of placers and ores containing precious metals (gold, platinum, silver), centrifugal devices (concentrators, separators) of various designs are used in the beneficiation schemes [1].

In the General case, these devices include a rotating from the drive the working chamber in the form of a conical bowl with a trap coating on its inner surface, most often in the form of annular grooves, feeding and unloading devices.

The main disadvantage of such devices is the low quality of the concentrate obtained and the low recovery of noble metals, especially small and fine fineness grades, due to the fact that during operation, the layer of material accumulated in the grooves, especially in the near-wall zone, is highly compacted under the influence of centrifugal force, which causes displacement light heavy particles are sharply reduced and the separation of pulp material becomes ineffective. That is why the well-known centrifugal separators SC-0.3 manufactured by the Russian company TulNIGP; SC-0.6; SC-1,0, in which this technical solution is implemented, have limited use in gold mining - in the development of alluvial deposits with large and medium gold.

In this regard, the development of new designs of centrifugal concentrators was carried out mainly in the direction of creating conditions for loosening the mineral "bed" accumulated in the annular grooves to ensure reliable segregation

small heavy particles into the grooves and thereby intensify the enrichment process.

One of the most effective technical solutions to achieve this goal compared to other known from special scientific and technical literature and patent sources is the use of intense vibrational vibrations of the working chamber (bowl) with a frequency exceeding the frequency of its rotation [2], [3], [ four].

In the known centrifugal concentrator [5] this is achieved through the use of a flexible inertial-friction drive of the shaft of the bowl to give it, along with rotation, an additional planetary rotation with a high rotation speed. However, due to the fact that the planetary motion in this concentrator design is associated with uncontrolled nutation (angular deviation of the axis of rotation of the bowl from the vertical), the expected efficiency of the extraction of the heavy useful component is reduced, especially in the middle and large classes. This is explained by a sharp increase in the radius of the planetary rotation of the bowl in the direction from the top of its cone to its base, i.e. to a sharp increase in the amplitude of the oscillations of the bowl. This deviation is also the cause of the demolition by the pulp stream of particles of small classes of the useful component (especially the lamellar and scaly forms), because additional acceleration arising due to the inclination of the bowl, directed across the grooves of the bowl, promotes not only loosening of the material, but also demolition. This leads to the need for additional cleaning of the "tailings" of the enrichment, which dramatically reduces the performance of the concentrator.

In another well-known centrifugal concentrator [6], [7] (taken as a prototype) manufactured by GRANT OJSC (Naro-Fominsk, Moscow Region) and found practical application in gold-platinum mining (CVK-300 model), for stabilization The enrichment process, the mutually contacting surfaces of the bowl shaft and the angle limiter are made with various profiles that facilitate the self-installation of the bowl from the initial rotation mode at an angle to the vertical to the planetary vertical or close to vertical rotation mode. In this case, the flexible element of the inertial-friction drive of rotation of the bowl is made with the possibility of spatial displacement of its driven part simultaneously in horizontal and vertical planes and the transmission of this displacement to the shaft of the bowl. To ensure the stability of the extraction, the known concentrator is equipped with an anti-resonance system.

However, as the operating experience of this concentrator shows, the moment arising from centrifugal force during the production of a certain (critical) mass of the concentrate

heavy useful component exceeds the resistance moment opposed by the flexible element. As a result of the imbalance in the moments of force, an uncontrolled increasing nutation of the bowl rotation axis arises, which cannot be visually detected during the operation of the concentrator, which entails the ejection of part of the accumulated concentrate from the upper grooves of the bowl and a sharp decrease in the recovery of the useful component.

Studies of the phenomenon of destabilization of the planetary vertical high-frequency rotation of the bowl depending on the mass of accumulated concentrate allowed the authors of this utility model to establish the following:

1. The implementation of mutually contacting friction surfaces of the bowl shaft and the limiter of the angle of inclination of the bowl with a different profile (for example, the surface of the limiter in the form of a cylindrical surface, and the working surface of the shaft of the bowl in the form of a convex spherical surface and vice versa) leads to a "sensitivity" of the force system to change the moment sides of the bowl, especially when accumulating concentrate in its upper grooves, causing nutation. In addition, this design of the profiles reduces the friction surface of the contact of the working part of the shaft of the bowl and the inner wall of the hole of the limiter of the angle of inclination of the bowl, which leads to uneven planetary motion due to the probability of slipping when the shaft rotates rapidly. Depending on the variable magnitude of the moment of friction between the shaft and the hole, the run-in is carried out either along a triangular or along a polygonal path, due to which the inertial forces acting on the solid particles of the pulp constantly change in magnitude several times. It is almost impossible to stabilize the enrichment process under such conditions.

2. The indefinite stiffness of the flexible element complicates the practical implementation of this technical solution for the design of a centrifugal vibration concentrator, since it depends on many factors (transmitted torque, mass of the bowl and its shaft, position of their centers of gravity relative to the limiter of the angle of inclination).

Thus, the dependence of the enrichment process on many design factors under conditions of strict stabilization of the motion parameters of the working chamber (bowl) reduces the efficiency of the known apparatus.

The technical problem to which the proposed utility model is aimed is to increase the efficiency of the process of separation of different density minerals in a centrifugal field, to increase the degree and quality of the extraction of heavy valuable

components by providing conditions for stabilizing the process of replacing light particles with heavy ones on the entire capture surface of the working chamber, regardless of changes in the process of enrichment of pulp parameters.

The solution to the technical problem is achieved by the fact that in a centrifugal vibration concentrator containing a working chamber in the form of a conical bowl with a friction shaft in its lower part and with a capture coating in the form of annular grooves on its inner surface, the mechanism for driving the rotation of the chamber through a flexible tube-shaped element, having the ability to deflect the camera from the vertical axis of rotation, displace it in the horizontal and vertical planes, a limiter of the angle of inclination of the camera, through which a friction the shaft in contact with the internal friction surface of the limiter, the limiter mounted on elastic shock absorbers on the base coaxially with the drive mechanism, the loading and unloading devices, the contacting surfaces of the friction shaft of the chamber and the limiter of its angle of inclination are cylindrical, with the lower driven part of the friction shaft equipped with a flywheel to balance the bending moment from the rotation of the chamber to ensure maximum extraction of the heavy useful component NTA.

The technical essence of the utility model of the proposed centrifugal vibration concentrator is illustrated as follows.

The implementation of the mutually contacting surfaces of the shaft of the bowl and the limiter of the angle of inclination with the same profile in the form of a cylinder increases the contact surface, especially with a slight difference in their diameters, which determines the amplitude of the vibrational vibrations of the bowl. This improves the operating conditions of the inertial-friction drive, reducing the likelihood of slippage during break-in and thereby stabilizing the trajectory of the planetary motion of the bowl and the inertial forces acting on the solid phase of the pulp. The enrichment process in such conditions becomes more efficient.

The supply of the lower driven part of the friction shaft of the bowl with the flywheel to balance the moment from its rotation gives the rapidly rotating system (bowl, shaft and flywheel) the property of a gyroscope - to counteract the forces striving to change the direction of its axis of rotation. In this case, these are: from the side of the bowl, the moment increasing from the mass of the produced concentrate as the power is supplied, and from the side of the driven part of the shaft, the moment of elasticity during bending and horizontal displacement

the plane of the flexible tubular element transmitting torque to the shaft from the drive.

Thus, these technical solutions ensure the fulfillment of the task - increasing the efficiency of the concentrator by stabilizing the enrichment process.

The claimed utility model is illustrated by drawings, where in Fig.1 shows a General view of a centrifugal vibration concentrator; figure 2 - diagram of the movement of the bowl in the initial period of its rotation; figure 3 is a diagram of the movement of the bowl in the steady state planetary motion.

The centrifugal vibration concentrator (CVC) contains a working chamber 1 in the form of a conical bowl with a friction shaft 2 in its lower part and with a catching coating 3 in the form of annular grooves on its inner surface. The bowl is driven into rotation by the drive mechanism 4 by means of a flexible element 5 of a tubular shape, configured to deflect it from the vertical axis, to displace it in horizontal and vertical planes and to transmit this deviation to the bowl through its direct connection with the shaft. The limits of deviations and displacements are set by the limiter 6 of the angle of inclination of the bowl, into the through hole of which a friction shaft is passed in contact with the internal friction surface 7 of the limiter. The limiter is mounted on elastic shock absorbers 8 coaxially with the drive mechanism on the base 9, on which a casing with a discharge device 10 is mounted. For supply, the hub is equipped with a loading device 11 in the form of a funnel. To balance the bowl during its rotation and to ensure its vertical planetary motion, the lower driven part of the friction shaft is equipped with a flywheel 12, made in the particular case in the form of a massive round clamp connecting the shaft of the bowl with a flexible element of the drive mechanism.

Centrifugal vibration concentrator operates as follows. Before the enrichment process starts, the drive mechanism 4 is started. When it is turned on, the bowl 1 through the flexible element 5 and the friction shaft 2 receives rotation around its axis and deviates from the vertical due to inertial forces. In practice, this initial deviation can also occur at rest, since the bowl, resting on the flexible element through the shaft, is in unstable equilibrium. The centrifugal forces arising during the rotation of the bowl 1 and the flywheel 12 create moments relative to the contact zone of the friction cylindrical surface 7 of the limiter 6 of the angle of inclination of the bowl, the equality of which is ensured by the corresponding mass of the flywheel. With such an equilibrium position

the rotating system (bowl, shaft and flywheel), its total flywheel moment acts on the limiter 6 of the angle of inclination of the bowl, mounted on the base 9 using elastic tubular shock absorbers 8, informing him of circular oscillations in the horizontal plane. As a result of such oscillations of the limiter, the system (bowl, shaft, and flywheel) self-installs from the initial rotation mode at an angle to the vertical to the operating mode of planetary vertical or close to vertical high-frequency rotation, acquiring the properties of a gyroscope. The gyroscopic effect in this case allows the rotating system to counteract the elastic forces of the flexible element when it is bent and displaced in the horizontal plane by an amount equal to the difference between the diameters of the contacting surfaces 7 of the limiter 6 and the shaft 2.

The operating mode of rolling the shaft along the inner working surface of the limiter flows stably due to reliable contact of friction surfaces and centrifugal forces during rotation of the bowl and flywheel.

After the bowl enters the operating mode (it is accompanied by a characteristic high-frequency vibrating sound), the initial pulp containing the enriched granular material (placer sands or ground ore) is fed into the feed funnel 11, from which it flows by gravity into the rotating bowl 1. Under the action of centrifugal forces, the material gets into the annular grooves of the catching cover of 3 bowls, where due to intense gyrations made by the bowl as a result of its high-frequency planetary motion, the material loosens and heavy small hours the particle, the useful component segregated inside "mineral bed," concentrating at the inner walls of the grooves. In this case, lighter fractions are washed out by water in an upward flow to the upper part of the bowl and then moved outside its limits to the unloading device 10 (tail-receiver), from which they are removed by gravity from the centrifugal concentrator. After the enrichment cycle, the drive mechanism is stopped, the loading funnel is removed and the concentrate is washed out of the grooves to the bottom of the bowl with a stream of water, from where it is removed by siphon (or other known devices) into the collection tank.

To confirm the effectiveness of the proposed technical solution, a prototype of the centrifugal vibration concentrator model TsKP-0.2 was made and tested on numerous samples of ground gold-bearing ores and non-traditional technogenic raw materials (battle of melting crucibles of precious metals), which has the following characteristics:

1. The largest internal diameter of the catching surface of the working chamber, mm - 90.

2. Depth of catching annular grooves, mm - 7. 3. Depth of the working chamber, mm - 75. 4. The amplitude of the planetary oscillations of the camera, mm - 2.5. 5. The frequency of rotation of the camera, rpm - 720. 6. The number of planetary vibrations of the chamber in min. - 6336. 7. Installed power, kW - 0.25. 8. Overall dimensions, L × W × H, mm - 455 × 285 × 400. 9. Weight, kg - 28.

The results obtained (see Table 1) showed that stabilization of the enrichment modes in all catch grooves of the working chamber of the new concentrator is ensured by the implementation of mutually contacting friction surfaces of the chamber shaft and its angle limiter with the same profile in the form of cylindrical surfaces, as well as installation on the lower driven parts of the flywheel shaft, balancing the bending moment during rotation of the chamber, allowed not only to significantly increase the extraction of precious metals, especially small, thin and ylevidnyh size fractions, compared with the prior art - known centrifugal concentrator vibration model CMC-100, manufactured by JSC "GRANT", but also broaden the scope of application - for the treatment of low grade (roughing) concentrates in order to increase the content of heavy components. (At the CVK-100-2M concentrator, treatment of heavy pulps already at the initial stage of enrichment causes the nutation of the working chamber, accompanied by the release of the useful component).

Table 1 Characteristics of raw materials
Name of indicator CVK-100 Prototype TsKP-0.2 Utility model A. London Field (Tanzania) Gold-Quartz-Arsenic Ore 1. Productivity, kg / h 75 75 2. Feed size, mm less than 0.5 less than 0.5 3. Gold recovery,% Fineness: from 0.5 to 0.25 mm 92 96 from 025 to 0.1 mm 86 92 from 0.1 to 0.05 mm 79 88 less than 0.05 mm 66 75 4. The volume of accumulated concentrate, ml 55 70

B. NPK "Supermetal" (Moscow) Platinum Crucible Fighting Crucible 1. Productivity, kg / h fifty fifty 2. Feed size, mm less than 0,074 less than 0,074 3. The recovery of platinum,% (total) 78 92 4. The volume of accumulated concentrate, ml 60 72

Thus, the claimed utility model fully fulfills the task, and its implementation in the conditions of mass production will allow equipping mining and geological enterprises with more advanced equipment not only for exploration for precious metals, but also for industrial enrichment in the development of gold deposits of placers, ores and technogenic raw materials.

Information sources

1. Lopatin A.G. "Centrifugal beneficiation of ores and sands." - M. "Nedra". 1987.S. 167-171.

2. Bogdanovich A.V. "Intensification of gravitational enrichment processes in centrifugal fields." - St. Petersburg. Ore beneficiation. 1999. No. 1-2. from 33-35.

3. Bogdanovich A.V., Petrov S.V. "Comparative tests of centrifugal concentrators of various types." - St. Petersburg. Ore beneficiation. 2001. No3. p. 38-41.

4. Bogdanovich A.V. "Theoretical foundations and methods for increasing the separation efficiency in the gravity concentration of ores." - Abstract of the dissertation for the degree of Doctor of Technical Sciences. - M. 2003.

5. RF patent No. 2109570, cl. B03B 5/32, 1995.

6. RF patent №2129047, cl. B03B 5/32, 1998.

7. Prospectus for the gold concentrator CVK-300 of the company GRANT OJSC

Claims (2)

1. A centrifugal vibration concentrator containing a working chamber in the form of a conical bowl with a friction shaft in its lower part and with a catching coating in the form of annular grooves on its inner surface, a camera rotation drive through a flexible tubular element that can deflect the camera from a vertical rotation axis, its displacements in horizontal and vertical planes, a tilt angle limiter of the chamber, through which a friction shaft in contact with the internal friction is passed through the surface of the limiter, while the limiter is mounted on elastic shock absorbers on the base coaxially with the drive mechanism, a loading and unloading device, characterized in that the mutually contacting surfaces of the friction shaft of the chamber and the limiter of its angle of inclination are cylindrical in shape, while the lower driven part of the friction shaft is equipped with a flywheel for balancing the bending moment from the rotation of the camera and maintaining a stable planetary vertical or close to the vertical rotation camera for maximum recovery of heavy useful component. 2. The centrifugal vibration concentrator according to claim 1, characterized in that the flywheel is made in the form of a massive round clamp for connecting the friction shaft with a flexible element of the camera rotation drive mechanism.