RU2263533C1 - Centrifugal mixer - Google Patents

Abstract

FIELD: food industry; chemical industry; other branches of industry; production of devices for continuous preparation of mixtures of the loose materials.

SUBSTANCE: the invention is pertaining to the devices for continuous preparation of mixtures of the loose materials and may be used in food, chemical and other industries. The centrifugal mixer contains: a vertical cylindrical body; a cover, on which there are the fixed connecting pipes for feeding of the source materials; a discharge connecting pipe; a driving shaft with an installed on it rotor made in the form of a disk, on which there are in the form of the disk on which one are the concentrically mounted hollow thin-wall truncated cones, the height of which and angle of the generatrix inclination to the base are increasing from the central part to the periphery. At that on the surface of the middle and the outside cones there are tangential holes. In the upper part of the body limited by the surface of the cover a static deflector is installed. The design of the apparatus ensures mixing of materials in the thin, rarefied, intersecting layers with usage of the direct and reverse recycles. The intensification of the mixing process is reached by that on the surface of the middle and the outside cones there are tangential holes, and also in the upper part of the body limited by the surface of the cover a static deflector is mounted. Due to that the invention ensures the reverse recirculation of the material flow, an additional turbulization of the mixed components, a decrease of the number of the quiescent areas in the various parts of the rotor and a degree of formation dust-gas mixes, that in result positively effects on the quality of the mixture.

EFFECT: the invention ensures the reverse recirculation of the material flow, an additional turbulization of the mixed components, a decreased number of the quiescent areas in the rotor and a degree of formation dust-gas mixes.

2 cl, 3 dwg

Description

The invention relates to devices for the continuous preparation of mixtures of bulk materials and can be used in food, chemical and other industries.

A known mixer [1], comprising a housing with a rotor located in it on a vertical shaft, which is three hollow truncated cones, which are concentrically mounted on the disk. In this case, the height and angle of inclination of the generatrix of each cone to the rotor disk increase from the central part to the periphery. Mixing in the specified mixer occurs as a result of the sequential passage of material on the surfaces of three cones under the influence of centrifugal forces. However, insufficient rarefaction of flows, lack of recirculation and the presence of stagnant zones in various parts of the rotor do not allow to obtain high-quality mixtures.

A known mixer [2], containing three cones, in which the height and angle of inclination of the generators to the base increase from the central part to the periphery. Four blades of the impeller of the axial fan are installed on the surface of the middle cone, due to which directional organization of the movement of air flows in the direction from top to bottom is ensured. As a result of the interaction of the air flow with the material flow, the latter is informed of additional turbulization and the degree of rarefaction of the leading material flows increases. The disadvantages of this design are the lack of reverse recirculation of the material, as well as the formation of a dust-gas mixture and the dispersion of components in the region between the rotor and the cover, which does not allow to obtain high-quality mixtures.

The purpose of the invention is the intensification of the process of mixing bulk materials with a ratio of starting components of 1: 500 and higher, increasing the smoothing ability of the mixer and, as a result, improving the quality of the resulting mixture.

Achieving this goal is ensured by the fact that tangential holes are made on the surface of the middle and outer cones, obtained by scanning two planes: the inner one directed opposite to the rotation of the rotor, and the outer one directed towards the rotation of the rotor. Since the material flow path relative to the rotor disk is twisted in the direction opposite to the direction of rotation, its movement is carried out along the inner plane of the tangential hole located at an angle to the surface of the cone, as a result of which the material detaches from the working surface of the cone, which ensures reverse recirculation. Since the outer plane of the tangential holes is directed in the direction of rotation of the rotor, then through their surface the directional organization of the movement of air flows into the cavity of the cones is tangential to their surface, as a result of the material flow additional turbulization is reported and the number of stagnant zones in the rotor is reduced. By varying the angles of the opening of the planes of the tangential holes, it is possible to change the amount of reverse recirculation and the degree of turbulization of the material flow.

The goal is also achieved due to the fact that in the upper part of the housing, limited by the surface of the lid, a static reflector is installed, consisting of the outer and inner rings, between which, at ninety degrees relative to each other, four guides are fixed, curved in an arc of a circle, working (concave ) whose surface is directed towards the rotation of the rotor. When the rotor rotates, the air located in the area between the rotor and the cover is also involved in the rotational movement, as a result of which a dust-gas mixture is formed in which particles of the finely dispersed components of the mixture are floating. Thanks to the installation of a static reflector, a swirling dust and gas stream with significant kinetic energy, under the action of inertial and centrifugal forces, is pressed to the surface of the guides of the spiral reflector, and is directed to the center of the rotor, where it is deposited on the surface of the inner cone. Thus, the presence of a static reflector contributes to the creation of directional circulation of the dust and gas flow in the region between the rotor and the lid of the mixer, which, in turn, positively affects the quality of the mixture.

Figure 1 shows a General view of a centrifugal mixer continuous; figure 2 - tangential hole with a diagram of the movement of material and air flows, the rotation of the rotor is carried out counterclockwise; figure 3 - static reflector in a perspective view.

The mixer consists of the following elements: a vertical cylindrical body 1, a cover 2 with loading nozzles 3, a drive shaft 4 with a rotor 5, made in the form of a disk 6 with concentrically arranged hollow truncated cones attached to it: inner 7, middle 8, outer 9. Height cones and the angle of inclination of their generatrix to the base increases from the central part to the periphery. On the working surface of the cones 7 and 8 there are four bypass windows 10, limited from below by the surface of the disk. On the working surface of the middle 8 and external 9 cones, tangential holes 11 are made above the bypass windows, obtained by scanning two planes: the inner 12 - opposite the rotation of the rotor, and the outer 13 - directed towards the rotation of the rotor. In the upper part of the casing, limited by the surface of the lid, a static reflector 14 is installed, consisting of the outer and inner rings 15, between which, at ninety degrees relative to each other, four guides 16 are fixed, bent along an arc of a circle, the working (concave) surface of which is directed towards rotor rotation. The shaft is mounted in bearing bearings 17 and is driven into rotation through a V-belt drive 18 from the electric motor 19. The mixture is unloaded through the discharge pipe 20 in the conical bottom 21.

Centrifugal mixer operates as follows.

Bulk components are dispensed by the dispensers into the loading nozzles 3 and fall on the bottom of the rotating cone 7. Under the action of centrifugal forces, the particles of the material accelerate from the center to the periphery, uniformly distributed on the inner surface of the cone, while the layer thickness on the periphery decreases due to an increase in the particle distribution surface. Part of the mixed materials moves through the windows 10, after which a rarefied, advancing stream enters the surface of the middle cone 8, which has a large height and the angle of inclination of the generatrix to the base. The other part moves along the generatrix of the inner cone 7 and is discharged through the upper base to the middle surface, where the main and leading flows overlap (i.e., the process of averaging of the components takes place). On the middle cone 8, the material flow is divided into three parts: the first, passing through the windows 10, advances to the surface of the outer cone 9; the second (main) moves along the surface of the cone and is dumped onto the surface of the subsequent cone; and the third part, breaking away from the working surface of the cone when the flow moves along the inner plane of the tangential hole, returns to the base of the middle cone. The mixture, passing the inner 7 and middle 8 cones, enters the outer cone 9. On the outer cone, the material flow is divided into two parts: the first under the action of centrifugal force moves along the inner surface of the cone and is thrown through the upper base into the space between the rotor and the housing; the second is detached from the working surface of the cone when the flow moves along the inner plane of the tangential hole, and the material returns to the base of the outer cone. Then the mixture enters the conical bottom 21, from where it is removed through the discharge pipe 20.

The intensification of the mixing process is achieved by the fact that tangential holes are made on the surface of the middle and outer cones, and a static reflector is installed in the upper part of the casing, limited by the surface of the lid. Due to this, the reverse flow of material flow is ensured, additional turbulization of the mixed components is reported, the number of stagnant zones in various parts of the rotor and the degree of formation of the dust and gas mixture are reduced, which, as a result, positively affects the quality of the mixture.

Sources of information

1. A.S. SU 1546120, A1, 1990, B 01 F 7/26.

2. Patent 2216394 of the Russian Federation, C1, 2003, B 01 F 7/26.

Claims (2)

1. A centrifugal mixer comprising a vertical cylindrical body, a cover on which nozzles for supplying raw materials are attached, an unloading nozzle, a drive shaft with a rotor mounted on it in the form of a disk, on which hollow thin-walled truncated cones are mounted concentrically with height and angle of inclination of the generatrix to the base increase from the central part to the periphery, characterized in that on the surface of the middle and outer cones there are tangential openings obtained by scanning two pl knock: inner - oppositely directed rotation of the rotor, and the outer - directed at rotor rotation. 2. The mixer according to claim 1, characterized in that in the upper part of the casing, limited by the surface of the lid, a static reflector is installed, consisting of external and internal rings, between which, at ninety degrees relative to each other, four guides are curved along an arc of a circle whose working (concave) surface is directed towards the rotation of the rotor.

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