SU990299A1 - Beads mill - Google Patents

Description

(54) BEARFILL MILL

one

The invention relates to the technique of fine grinding, intended to disperse. The use of powdery materials in a liquid medium can be used in the chemical, food and other industries.

The famous bead mill, the main components of which are a container, comprising a housing with fittings for inlet and outlet of coolant, inside of which is mounted a grinding chamber with an agitator, grinding bodies and a nozzle for entering the crushed product, a receiver with a nozzle for leaving the suspension, a filter for separating grinding tel from the product and electric drive.

In a known mill, a filter for separating the grinding bodies is either mounted above the grinding chamber or inside it 1.

During operation, the filter holes are often clogged with grinding bodies or product particles, and filters located in the grinding zone wear out and tear quickly.

Closest to the invention to the technical essence is the bead

the mill containing a grinding chamber with a cooling jacket is a vertical shaft placed in the chamber with working discs and a drive, as well as a filter member with a flange, a spiral and a profiled disc adjacent to the flange surface.

When the mill is filled with grinding bodies at 1/3 of its volume and the processing of low viscosity slurries, the device helps to separate the grinding media from the product and return them to the grinding zone 2.

However, it is not very effective when dispersing viscous suspensions and working under pressure.

It is known that a significant increase in fine grinding performance can be achieved by filling the grinding chamber 0.8 of its volume with grinding bodies and processing the suspension under pressure. In this case, the device does not separate the grinding media from the product. The grinding bodies fall into the vertical gap between the shaft and the nozzle, collapse, clog the mesh and degrade the quality of the product.

The aim of the invention is to increase productivity and improve the quality of grinding.

This goal is achieved by the fact that in a bead mill containing a grinding chamber with a cooling jacket, a vertical shaft placed in the chamber with working discs and a drive, as well as a filtering body with a flange, a spiral disk and adjacent to the surface of the flange of a profiled disk, the flange surface of the filtering body and The profiled disk facing each other is provided with annular recesses of the triangular profile in cross section, with flange projections located between the projections of the disk.

In this case, the profiled disk can be equipped with blades fixed along the perimeter of the disk on its cylindrical surface and at an acute angle to the disk plane, and annular grooves are made between the projections on the profiled disk.

When the shaft rotates, the blades intensively throw the grinding bodies to the chamber wall and contribute to the creation of fluid flows that move them in a spiral to the grinding zone. Large aggregates of particles are also returned to the grinding zone, not having time to break down. Particles that fall into a zigzag gap between the disk and the flange are subjected to segregation and additional abrasion in the gap as a result of the presence of a velocity gradient of the liquid layers. The action of centrifugal force contributes to the rejection of large particles from the gap. Making a slit of zigzag cross-section ensures the segregation of particles, the separation of large and heavier from small ones. The grooves between the protrusions on the surface of the disk serve as traps for the fragments of grinding bodies and other foreign particles that fall into the slot.

This embodiment of the filtering body ensures reliable separation of grinding media and impurities from the suspension. Any viscosity, increased productivity and high quality of the product due to the operation of the mill under pressure and efficient grinding of particles in the gap.

The drawing shows a bead mill with partial tearing of the wall.

The mill has a housing 1 with a cooling jacket 2. Inside the case there is a vertical shaft 3, rotated by an electric motor 4. Working dike 5 is fixed on the shaft. In the upper part of the case above the working disks there is a filtering body, including flange 6, helix 7 and disk 8 s blades 9. The material for grinding enters the chamber through the nozzle 10, and leaves the mill through the chute 11. The nozzles 12 and 13 serve to enter and exit the coolant.

The mill is filled to 0.8 of its volume in the grinding chamber with grinding media, water is allowed to cool. Then the motor 4 is turned on and supplied through the pipe 10 into a viscous suspension under pressure. The grinding bodies rise to the upper disk. Due to the high pressure, the forces acting between them increase, which contributes to a more efficient destruction of solid particles of the suspension. Blades 9, mounted at an angle to the plane of the upper disc, discard the grinding bodies against the wall and facilitate their downward spiral movement. The suspension is pressed into the gap of zigzag cross section between the flange and the disk and the particles of its solid phase are subjected to segregation and intense additional abrasion in the gap. Large aggregates that have penetrated into the gap are either thrown out of the slot and hit by the blades, or are destroyed as a result of abrasion. Solid and heavy fragments of bodies and other extraneous inclusions, trapped in the slot, linger in the grooves of the catchers and periodically, during the cleaning of the mill, are thrown out of them.

The use of the invention in mills when dispersing viscous suspensions under pressure makes it possible to increase the reliability of operation, the productivity of the mill and the quality of the produced product.

Claims (3)

1. A bead mill containing a grinding chamber with a cooling jacket, a vertical shaft placed in the chamber with working discs and a drive, as well as a filtering organ with a flange, a spiral and a profiled disk adjacent to the flange surface, so as to increase productivity and improving the quality of grinding, the surface of the flange of the filtering body and the profiled disk, facing each other, are made with annular recesses of the triangular profile in cross section, while the protrusions of the flange are laid between the drive lugs. 2. A mill according to claim 1, characterized in that the profiled disc is provided with blades fixed along the perimeter of the disc on its cylindrical surface and at an acute angle to the flat plate. 3. Mill according to claim 1, characterized in that annular grooves are made between the protrusions on the profiled disk. Sources of information taken into account in the examination 1.Sidenko P.M. Grinding in the chemical industry of M., “Chemistry, 1977, p. 129. 2. USSR author's certificate number 657845, cl. B 02 C 17/16, 1977.