SU856561A1 - Method of hydraulic classification of loose materials - Google Patents

Description

(54) METHOD FOR HYDRAULIC CLASSIFICATION OF BULK

I

This invention relates to methods for the hydraulic classification of bulk materials), in particular to methods.

hydraulic classification of microspheres.

The known method of hydraulic classification is that the initial pulp is fed from above and mixed with the upward flow of water, the upward flow of the mixture is laminarised and the fine fraction L3 is carried out by the laminar flow.

However, this method cannot separate the powders into fractions with a very narrow deposition rate interval in each fraction, and it is also impossible to separate the powder, all particles of which have the same sedimentation or floating rate, but differ in the symmetry of the external contour relative to the center of gravity, for example, hollow microspheres.

The closest in technical. The essence and the achieved result MATERIALS

The proposed method is the hydraulic classification of bulk materials, which includes the introduction of a section into a horizontal laminar flow. perpendicular to the source material in the form of a suspension and the removal from the stream of particles with identical vertical speeds at different distances from the point of entry G23.

ten

This method allows the separation of powders in inert liquids into fractions with a narrow range of sedimentation rates, but is unsuitable for separating powders whose particles have equal sedimentation or floating rates into fractions and differing in symmetry of the outer contour relative to the center of gravity.

Claims (2)

The purpose of the invention is to improve the efficiency of classification in the separation of particles different in distance to the center of gravity relative to the center of symmetry of the external contour. This goal is achieved by the fact that with the method of hydraulic classification of bulk materials, including the introduction of a separating medium into a horizontal laminar flow, the perisal width of the source material in the form of a Suspension and the removal of particles from the flow with the same vertical speeds from the point of entry, the flow is reported to move in a circle, and the loading of the source material is carried out in a horizontal plane. The essence of the described method is that particles of one fraction, with a narrow range of settling or floating rates, are introduced into the mountains. the vertical direction in the respective upper and lower parts of the flow, perpendicular to the flow axis. Entering particles in the indicated directions eliminates the influence of the rate of introduction of particles on the separation accuracy. Pre-milling, flowing through the chamber completely filled with liquid, I inform the forward movement around the circumference. In order to communicate such movement to the flow walls of the chamber, there should be no air bubbles in the chamber, since a wave appears on the exposed surface of the fluid and overwhelms the current imparted motion. . Forward motion along a circle should have a speed that ensures the swirling of particles whose outer contour is asymmetric with respect to the center of gravity. A flow that has a circular translational movement carries particles located in it, with the resultant force acting on the particle passing through the center of the cross-sectional area of the particle. If the center of the particle cross-sectional area does not coincide with the center of gravity of the particle, then the inertial forces passing through the center of gravity of the particle and the resultant force of the flow create a moment unwinding the parts. This method will allow sorting microspheres with different wall thickness, with inclusions in the walls of gas bubbles, spherically asymmetric microspheres. FIG. 1 shows the device, the general view; FIG. 2 is a section A-A in FIG. If in FIG. 3 is a projection of the microsphere trajectory in the horizontal plane, which it passes along with the fluid in the sump. The flow of the separating medium to the circumferential movement of the walls of the chamber is achieved by the sump I. with a collection of sectional products, type 2 is installed on four crankshafts 3. Electric motor 4 informs point A of the sump around the circumference using crank 5. All cranks have the same radii Ki are installed parallel to each other; therefore, displacement of point A by crank 5 results in a similar displacement of points B, C, D, D. Continuous displacement of point A along a circle leads to continuous displacement of points B, C, D, D4 in a circle. With this movement, any point of the sump I, and therefore and the flow through the sump, perform translational motion along a circle of radius R in the horizontal plane, rather than reciprocating, which requires a periodic change in the direction of rotation of the electric motor. The flow rate through the sump is significantly less than the speed of translational movement around the circumference. The projection of the microsphere trajectory in the horizontal plane is a circle of radius j which shows several positions of the microsphere with a mismatch of the center of gravity and the center of symmetry of the outer surface. Any body moves in a circle only under the action of forces imparting to it centripetal acceleration. The resultant force of the fluid on the microsphere, together with the latter, is centrifugal acceleration O, passes through the center of symmetry of the outer surface. The centripetal acceleration leads to the inertial force of the Fy microsphere, which passes through its center of gravity and is directed from the center of a circle of radius R. On microspheres, the center of gravity of which does not coincide with the center of symmetry of the outer surface, a moment of rotation tends to result symmetry and center of gravity on the line of action of centripetal acceleration. This causes the microsphere to rotate around its axis by one turn with one cycle of its movement around a circle of radius R. The turning microsphere entrains the fluid layers adjacent to it, which leads to the formation of vortices in the horizontal plane in the fluid layers surrounding it. This leads to a decrease in the velocity of the surface we carry metric microspheres. Microspheres, the center of gravity of which and the center of symmetry of the outer surface coincide, do not twist and their rate of emergence does not change. The proposed method can be used to sort abrasive powders whose particles have the same sedimentation rate, but differ in shape, i.e. p, l separation of elongated drop-shaped particles. In addition, the method allows the separation of particles with inclusions from different-density materials, which can be used for enrichment or purification of bulk materials in inert liquids. Claims The method of hydraulic classification of bulk materials, including the introduction of a separating medium into a horizontal laminar flow, perpendicular to it, of a raw material in the form of a suspension and removing particles B from the flow with identical vertical speeds at different distances from the point of entry, that, in order to increase the efficiency of classification in the separation of particles different in the distance of the center of gravity relative to the center of symmetry of the outer contour, the flow is reported to move around NOSTA and loading the starting material is performed in the horizontal plane. Sources of information received in attention during examination 1. USSR author's certificate No. 230046, cl. B 03 V.5 / 62, 1967. 2. USSR author's certificate number 231456, cl. At 03 B 5/60, 1964 (prototype).