RU102312U1 - DEVICE FOR SEPARATION OF PARTICLES FROM BULK MATERIALS - Google Patents

Abstract

 1. A device for separating particles from bulk materials, including a device for loading and feeding particles, a supercharger of air to ensure the flight of particles and a returning surface, characterized in that the device for loading and feeding particles is made in the form of a slit nozzle, which ensures the creation of disjoint flight paths particles, and the returning surface is profiled and installed with the possibility of providing reflection from it at least part of the flying particles at different angles and with different speeds depending on the properties of the particles. ! 2. The device according to claim 1, characterized in that the reflection from the profiled surface of at least a portion of the flying particles at different angles and at different speeds is provided depending on the recovery coefficient and the sliding friction coefficient of the particle-surface pair. ! 3. The device according to claim 1, characterized in that the profiled surface is made and installed with the possibility of providing a multiple increase in the distance between the flight paths of particles with different properties after reflection from the said surface, by selecting a surface profile for a specific mineralogical composition of the particles. ! 4. The device according to claim 1, characterized in that the height of the cross section of the slit is made equal to the particle size of the largest fraction.

Description

The invention relates to devices designed for the separation of particles of bulk materials, differing in density, as well as in the recovery coefficient and coefficient of sliding friction paired with a material of a certain surface, and can be used in metallurgical, enrichment, construction and other related industries.

The closest analogue is a device for separating particles from bulk materials of various densities, including a device for loading and feeding particles, containing a chamber in the form of an acceleration tube with an air blower in the form of a pneumatic blower to create disjoint flight paths of particles of different densities and a device for loading particles integrated in the chamber, installed at the outlet of the booster pipe, a separation chamber with transverse partitions located at the bottom of the separation second chamber sequentially from the output end of the booster tube. An aspiration system and bunkers with discharge pipes are installed between the separation walls, vibro-baffle plates are installed on the baffle surfaces to meet the outlet end of the baffle pipe, directional nozzles are installed on the transverse baffles. Each baffle plate is installed with the possibility of adjusting the height of the arrangement on the corresponding transverse partition, and the directional nozzles are installed opposite to the corresponding vibro-baffle plates (see SU 1789307 A1, publ. 23.01.1993).

The disadvantage of the closest analogue is the design complexity and low efficiency of the separation process due to the implementation of the classification node in the form of several identical fenders in the form of plates.

The objective of the invention is to increase the efficiency of separation of particles depending on their physical properties.

The problem is solved in that the device for separating particles from bulk materials includes a device for loading and supplying particles, a supercharger of air to ensure the flight of particles and returning (fencing) profiled surface, while the device for loading and feeding particles is made in the form of a slotted nozzle, providing creation of disjoint particle flight paths, and the returning profiled surface has a profile selected by calculation for a certain mineralogical composition of the shared mixture and, and is set to provide a reflection from it at least a portion of the particles flying at different angles and at different speeds, depending on the physical properties of the particles.

An increase in the efficiency of the ballistic particle separation process occurs due to the additional separation of particle trajectories with different properties, for example, different friction and sliding coefficients paired with a material of a certain surface, which is achieved as a result of impact and bounce of particles from the return profiled surface at different angles and with different angles speeds, depending on the recovery coefficient and the coefficient of sliding friction of the particle-surface pair. A special separation effect is achieved by calculating and constructing a surface profile.

In a particular embodiment of the invention, the cross-sectional height of the slit is made equal to the particle size of the largest fraction, and the surface is made and installed with the possibility of providing a multiple increase in the distance between the flight paths of particles with different physical properties after reflection from the said surface, compared with the paths of the same particles to collisions with the surface.

The invention is illustrated by drawings.

Figure 1 shows a General diagram of the device, figure 2 shows a nozzle, side view, figure 3 - nozzle top view, figure 4 - nozzle, front view, figure 5 as an example shows a diagram of a device for separation intermediate products of processing sulfide copper-nickel ores.

The device consists of a loading device made in the form of a slotted nozzle 1 (Fig. 1), with an air blower (not shown in the drawing), a profiled surface 2 for separating particles mounted on the rack 3, bins 4, 5 and 6 for separate particle products.

The operation of the device consists of two main operations occurring in a pseudo-continuous mode: preparatory separation of particle flight paths and shock redirection.

1. Preparatory separation.

In order to redirect particles with different densities to the corresponding areas of the returning surface, it is necessary to separate their flight paths. The mass of particles calibrated by particle size distribution is proportional to their density. Therefore, acting on particles with a constant force, the particles can be given different initial acceleration, which will cause the separation of the trajectories of their further free flight.

In the proposed device, imparting acceleration to the particles is implemented using a horizontal slotted nozzle (Fig.2-4). By supplying air to the nozzle, a flat stream of air is created. In the wide upper wall of the nozzle, as close as possible to the plane of the cut, there is a loading slot 7 (figure 2). The height of the slit cross section is selected for the desired material, depending on the particle size and mineralogical composition, while no more than one particle of the largest fraction passes through the cross section of the slit. Particles along the entire width are fed to the gap and are poured into the nozzle. Particles are accelerated by the pressure of passing air. Depending on the mass, the particles receive different initial acceleration and different trajectories of free movement after exiting the nozzle. The projection of the distance traveled by the particle on the horizontal axis depends only on its mass (figure 5):

where ΔL is the projection of the distance traveled by the particle on the horizontal axis,

F ₀ - force acting on particles (constant value for all particles),

m is the mass of the particle,

τ is the flight time of the particles (the value is constant, because after a period of time , N - nozzle height, all particles reach the surface of the earth).

Thus, with calibrated geometric parameters of the particles, their density determines the path of free flight. The flat horizontal jet is due to the need to reduce the probability of intersection of the trajectories of two neighboring particles.

2. Impact redirection.

A profiled surface 2 is installed along the free flight path of the particles. The profile configuration is calculated for a specific material composition taking into account the estimated overall dimensions of the installation, air pressure in the nozzle 1, and the number of phases that must be separated. Particles with low density, easily separated by ballistic methods, fly as far as possible from the nozzle in the direction perpendicular to gravity, and are collected in the receiving hopper 4. Particles with high density hit the profiled surface 2 and bounce from it at different angles and with different speeds. The ratio of the angle of reflection and the angle of incidence of particles is greater and the speed of their rebound is lower, the lower the recovery coefficient and the higher the friction coefficient of sliding of the particle-surface pair. Accordingly, particles with a low recovery coefficient and a high coefficient of sliding friction paired with the surface are poured into the hopper 5, which is installed in the immediate vicinity of the profiled surface. Particles with a high recovery coefficient and a low coefficient of friction bounce off the surface at a certain distance and are collected in a separate hopper 6 (Fig. 1). Particle trajectories do not intersect, because in the vertical section there is a trajectory of only one particle, which is achieved by using a narrow slotted nozzle to eject particles. The speed that a particle possesses after an impact is:

where: u is the particle velocity after impact;

K is the recovery coefficient;

v is the particle velocity before impact;

α is the angle to the normal to the surface when falling;

f is the coefficient of sliding friction. The angle to the normal to the surface after impact is equal to:

where: β is the angle to the normal to the surface after the rebound.

For each type of material (sulfide copper-nickel ores, river sand, etc.), a profile is selected that ensures the proper redirection of particles with various properties to different receiving bins. The calculation of the surface profile configuration is made taking into account the speeds and geometric characteristics of the particles, as well as the trajectories of their free flight using mathematical models of particle impact on the surface:

where u is the particle velocity modulus after impact,

u _r is the tangential component of velocity after impact,

u _n is the normal component of the velocity after impact,

v is the particle velocity before impact,

f is the coefficient of sliding friction,

K is the recovery coefficient,

α is the angle between the path of the particle before the impact and its projection on the profiled surface at the moment of contact,

β is the angle between the trajectory of the particle after impact and the normal to the profiled surface at the point of contact. According to the profile, a working profiled surface is made.

The following is an example of the separation of intermediate products of the processing of sulfide copper-Nickel ores using the proposed device (figure 5).

Separated particles of various phases: sulfide, phases of noble metals and phases of slag-forming compounds are fed into the nozzle 1, which has a polished surface and is made of a material with a minimum coefficient of friction paired with particles (e.g., hard alloy). At the same time, air is supplied to the horizontal and flat slit chamber under constant pressure. The passage width of the slot is 0.1-0.2 mm. Depending on the density, particles under the influence of air flow acquire different speeds at the outlet of the nozzle in a direction perpendicular to gravity, as a result of which their flight paths are separated. Particles represented by phases of light slag-forming compounds fly over a profiled surface and fall into hopper 4, from where they are transferred to a tailing dump or slag dump. The heavy particles represented by the phases of the noble metals, along their path, fall into their hopper 5 for further transfer to refining. All particles of intermediate density (sulphide phase) hit the profiled surface and along the rebound path fall into their hopper 6: the impact and rebound from the surface greatly enhances the effect initially achieved by separation of the paths. Particles of the sulfide phase bounce off at a calculated angle to the main direction of particle motion (they leave after hitting up and to the side).

The proposed device allows you to contrastively divide the three main products inherent in the beneficiation and metallurgical operations: concentrate, recycled product and dump product. The introduction of kinetic separation in the technological scheme as an operation to concentrate precious metals in the charge of smelters and electrolyte copper and nickel sludge significantly reduces the return load of the apparatus involved in the enrichment of dry mineral materials. Extraction of precious metals from raw materials is increased, the process does not require the use of water, energy costs are minimal. The process is continuous, easily automated and does not create harmful emissions.

Claims (4)

1. A device for separating particles from bulk materials, including a device for loading and feeding particles, a supercharger of air to ensure the flight of particles and a returning surface, characterized in that the device for loading and feeding particles is made in the form of a slit nozzle, which ensures the creation of disjoint flight paths particles, and the returning surface is profiled and installed with the possibility of providing reflection from it at least part of the flying particles at different angles and with different speeds depending on the properties of the particles. 2. The device according to claim 1, characterized in that the reflection from the profiled surface of at least a portion of the flying particles at different angles and at different speeds is provided depending on the recovery coefficient and the sliding friction coefficient of the particle-surface pair. 3. The device according to claim 1, characterized in that the profiled surface is made and installed with the possibility of providing a multiple increase in the distance between the flight paths of particles with different properties after reflection from the said surface, by selecting a surface profile for a specific mineralogical composition of the particles. 4. The device according to claim 1, characterized in that the height of the cross section of the slit is made equal to the particle size of the largest fraction.