RU2322301C1 - Method and device for super-fine disintegrating of material - Google Patents

Abstract

FIELD: disintegrating of loose materials.

SUBSTANCE: method comprises supplying material to the dryer, classifying material into fine class that is supplied to the large-diameter pipe through the batcher connected with the disintegrating chamber and coarse class that is disintegrated and mixed with the fine class, and supplying material to the disintegrating chamber by means of air ejecting. The chamber is tangentially connected with the cyclone. The particles are provided with additional stress that is caused by the sudden change in rotation of gas mixture from horizontal (disintegration chamber) to vertical (cyclone) and by multiple collisions of particles with walls of the chamber and one with the other.

EFFECT: simplified method and enhanced efficiency of device.

4 cl, 1 dwg

Description

The invention relates to equipment for grinding bulk materials and can be used in industries: chemical, petroleum for grinding bentonite clays, metallurgical, paint and varnish, in construction in the production of dry building mixtures, as well as in other industries where fine grinding is necessary under the production conditions and activation of bulk materials.

A known method of grinding polymer materials and a device for its implementation, in which particles of the material are accelerated, and then hit the stationary parts of the mill (RF application No. 94006696, V02C 23/00, from 24.02.1994, publ. 20.10.1995). This method allows for fine grinding of materials, but the method is low productivity, and the device for its implementation is too complicated.

Known countercurrent jet mill containing booster tubes introduced into the grinding chamber (application of the Russian Federation No.2000128609, B02C 19/06, from 16.11.2000, publ. 10.04.2001). The device is complex in design, its performance is low.

A known method of ultrafine grinding of materials, including preliminary crushing of the material, the organization of the flow of gas suspension with particles of material, the introduction into the grinding volume of the grinding chamber of the gas suspension, the creation in the grinding volume of a complex of disturbing effects on the flow field and density disturbances in the form of shock waves and discharges, providing conditions for contact the interaction of material particles between themselves and with the working surfaces of the grinding chamber, classification and sedimentation of the finished product (patent R №2070094, V02S 19/06, from 06.12.1993, publ. 10.12.1996). This method provides fine grinding of materials, activates the material, but is very difficult to use in an industrial environment, and complex devices are needed to reproduce the method. In addition, this method is inefficient.

Known jet installation for grinding bulk material containing a grinding chamber with a device for supplying gas (air), a hopper with a dispenser and a device for separating gas suspension (RF patent No. 2079366, from 04.07.1995, publ. 05.20.1997 - prototype). This installation grinds material well, but is complex in design and inefficient.

The objective of the invention is to simplify the method of ultrafine grinding of material and a complex of means for its implementation. In addition, the object of the invention is to increase the productivity of the complex.

The problem is solved in that in the method of ultrafine grinding of materials and a set of tools for its implementation, including preliminary crushing of the material, the organization of gas suspension flows with particles of material, the introduction of a gas suspension into the grinding volume of the chamber, the creation in the grinding volume of the grinding chamber of disturbing effects on flow fields and disturbances density in the form of shock waves and rarefaction, providing conditions for contact interaction of material particles with each other and with the working surfaces of the chamber grinding, classification and sedimentation of the finished product, according to the invention feed the material by ejecting gas (air), twist the gas suspension and feed it into the grinding chamber along the front wall, and precipitate the material in the cyclone, while the horizontal direction of rotation of the gas suspension in the grinding chamber changes dramatically vertical rotation in a cyclone.

In the method according to paragraph 1 of the invention, the material is pre-dried, it is divided into fractions, for example in a vibrating screen, the coarse fraction is sent to the grinding, and the fine fraction from the sieve and after grinding is sent to the hopper, and then for further grinding and activation.

In the complex of means for ultrafine grinding, including a grinding chamber with a device for supplying gas (air), a hopper with a dispenser and a device for separating a gas suspension, according to the invention, the device for supplying gas (air) is made in the form of a pipe with a nozzle connected to a pipe of a larger diameter, in which a hole is cut for connecting it to the hopper, while the pipe of larger diameter is connected to the grinding chamber, while at the end of the pipe at the junction of it with the grinding chamber a swirler is installed, made, for example, in the form of a cone with spiral coils fixed on it, and the grinding chamber is made in the form of a large-diameter pipe, the front wall of which in the direction of air movement is made in the form, for example, of a diffuser, and the grinding chamber is connected tangentially to the cyclone (gas suspension separation device).

The complex according to paragraph 3 is made so that it further includes a dryer for drying the material, for example, a vibrating screen for dividing the material into fractions, for example, a vibrating mill for grinding a large fraction of the material.

Analysis of the proposed solution with the prototype allowed us to highlight the features that distinguish the proposed solution from the prototype, which meets the criterion of "novelty." A comparative analysis of the proposed solution with known solutions did not reveal signs that match the distinctive features of the proposed solution, which meets the criterion of "inventive step".

The invention is illustrated in the drawing, which shows schematically a complex.

According to the proposed method, the material is first dried in a dryer, and then separated into fractions on a sieve (for example, a vibrating sieve) and a fraction with a particle size of more than 100 μm is sent to grinding, for example, to a vibrating mill. Sieves and mills can be different in their design and principle of operation. A fraction of 100 μm or less separated on a sieve and ground in a mill enters the hopper for further grinding and activation.

Next, a gas suspension flow with material particles is organized in such a way that in the gas suspension grinding chamber, the material particles repeatedly collide with each other, as well as with the walls of the grinding chamber due to disturbing effects on the flow field, creating shock waves and rarefaction due to a change in the gas suspension flow velocity. The twisting of the gas suspension in the grinding chamber and separation in the cyclone (device for separating the gas suspension) is accompanied by a change in horizontal rotation in the grinding chamber to a vertical rotation in the cyclone. The complex total movement of particles with a strong dynamic effect from collisions of particles between themselves and the walls and guide elements of the chamber creates internal stresses in the particles, leading to their cracking and destruction.

Material is supplied by ejection of gas (air).

Twist the gas suspension and feed it into the grinding chamber at a high speed, which drops sharply in the grinding chamber due to the large diameter of the chamber. The gas suspension is fed along the front wall (in the direction of the gas) of the grinding chamber and strikes the horizontal walls of the chamber with force.

The method of ultrafine grinding of materials is carried out by a complex of means for ultrafine grinding. The complex consists of an ultrafine grinding chamber 1 with a device for supplying gas (air) 2, a hopper 3 with a dispenser 4 and a device for separating gas suspension (cyclone) 5. The device for supplying gas (air) 2 consists of a pipe with a nozzle 6 connected to the pipe larger diameter 7. A hole 8 is cut in the pipe 7 for connecting it to the hopper 3. The pipe 7 is connected to the grinding chamber 1. At the end of the pipe 7, at the point of its connection with the grinding chamber 1, a swirler 9 is installed, made, for example, in the form of a cone with fixed spiral coils on it 10. Zavi chrysalis 9 can be made in the form of a pinwheel, step cone, egg, etc. The grinding chamber 1 is made in the form of a pipe of large diameter, the front wall of which in the direction of gas (air) is made in the form, for example, of a diffuser 11. The front wall can be made in the form of a plate, a profiled disk with a hole, etc. The grinding chamber 1 is connected to a device for separating a gas suspension (cyclone) 5 tangentially. The complex of means for ultrafine grinding of materials further includes a dryer 12, for example, a drum, for drying the material. Structurally, the dryer can be any. After drying the material in the dryer 12, it is fed by noriya (not shown), for example, into a vibrating screen 13 (or other device) to separate the material into fractions. In this case, particles larger than 100 μm are sent, for example, to a vibratory mill 14 (mills can be structurally any) for grinding to a fineness of 100 microns or less. Fractions with a fineness of grinding material of 100 μm or less from the vibrating screen 13 and from the mill 14 are fed into the hopper 3 for further ultrafine grinding and activation.

The complex works as follows. Material (for example, ash from CHPPs) from the storage is fed, for example, by a conveyor belt (not shown) to dryer 12. After drying, the material is noria (not shown) fed to a vibrating screen 13, where it is divided into two fractions. Particles larger than 100 μm (the first fraction) are fed to the grinding mill 14, and a fraction of particles with a size of less than 100 μm is fed to the hopper 3.

After grinding in a vibration mill 14 to a fineness of grinding particles of 100 μm or less, the material is also fed into the hopper 3. Through the pipe 2 with high speed through the nozzle 6, for example, gas (air) is supplied from the compressor (not shown) to a pipe of a larger diameter 7. Opens a flap (not shown) in the hopper 3, installed in the hole 8, and the material from the hopper 3 through the dispenser 4 is uniformly fed into the pipe 7, and since the pipe 7 is much larger in diameter than the device for supplying gas (air) 2, the speed of the gas suspension drops sharply. As the air moves forward through the swirl 9, made in the form of a cone with spiral coils 10 fixed on it, the gas suspension velocity increases sharply due to the narrowing of the pipe 7. The gas suspension is twisted by the spiral coils 10 and enters the grinding chamber 1 at high speed in two streams: one stream along the front wall (in the direction of the gas), made in the form of a diffuser 11; another stream in the form of a swirling spiral directly into the grinding chamber 1. As it approaches the cyclone 5, it forms a funnel into which the gas suspension is sucked in with great force. Since the grinding chamber in its diameter significantly exceeds the pipe 7, the gas suspension velocity decreases. When moving through the pipe 7, the gas suspension particles collide with each other repeatedly, hit the turns of the spiral 10 of the swirl 9, and then, moving along the front wall 11, made in the form of a diffuser, hit the outer walls of the grinding chamber 1. Multiple jumps in speed lead to compression and sharp the decompression of material particles, which contributes to the appearance of internal stresses in them and the strengthening of defects, which, when multiple particles collide with each other and the walls of the pipe 7, coils 10, swirl 9 and the walls of the grinding chamber 1 lead to the appearance of numerous cracks in the particles and, ultimately, to the destruction (grinding) of the particles. The final destruction of particles occurs due to a sharp change in the horizontal direction of rotation in the grinding chamber 1 to the vertical in the device for separating the gas suspension (cyclone) 5. This occurs due to the tangential connection of the grinding chamber 1 with the device for separating the gas suspension (cyclone) 5. In cyclone 5, the gas suspension rotates in a vertical plane, air rises up the cyclone and is discharged outside (into the atmosphere), and particles of material are deposited. Multiple collisions of material particles on the walls of the pipe 7, the coils of the spiral 10, the swirl 9 and the walls of the grinding chamber 1, in addition to the destruction of the particles, lead to the accumulation of additional energy in the particles, that is, their activation. Milled and activated in this way, for example, the ash of a thermal power station made it possible to obtain particles with a size of 50 μm or less with an activity corresponding to the cement grade 400 ... 700.

Thus, the proposed method of ultrafine grinding of materials and a set of tools for its implementation is simple in its technology and design and can significantly increase the grinding performance.

Claims (4)

1. A method of ultrafine grinding of materials, including preliminary crushing of the material, organization of gas suspension flows with particles of material, introduction of the crushed gas suspension into the grinding chamber volume, creation of disturbing effects on flow fields and density disturbances in the form of shock waves and rarefaction in the grinding chamber volume, ensuring conditions for contact interaction of material particles with each other and with the working surfaces of the grinding chamber, classification and sedimentation of finished products, excellent In that it feeds the material with the help of air ejection, twists the gas suspension and feeds it into the grinding chamber along the front wall in the direction of air movement, causing the particles of material to repeatedly collide with each other and with the walls of the chamber, and precipitate the material in a cyclone, while changing the horizontal the direction of rotation of the gas suspension in the grinding chamber for vertical rotation in the cyclone. 2. The method according to claim 1, characterized in that the material is pre-dried, it is divided into fractions, for example in a vibrating screen, the coarse fraction is sent to grinding, for example in a vibrating mill, and the fine fraction from the sieve and after grinding are sent to the hopper, and then to further grinding and activation. 3. A set of means for ultrafine grinding, including a grinding chamber with an air supply device, a hopper with a dispenser and a gas suspension separation device, characterized in that the air supply device is made in the form of a pipe with a nozzle connected to a pipe of a larger diameter, in which a hole for connecting it to the hopper, while the pipe of larger diameter is connected to the grinding chamber, and at the end of the pipe at the junction of it with the grinding chamber is installed a swirl made in the form of a cone with fixed nnym thereon spiral turns, and the grinding chamber is a tube with a diameter larger than the diameter of the preceding pipe, wherein the front wall of the air flow is formed as a diffuser, wherein the grinding chamber is connected tangentially to the cyclone. 4. The complex according to claim 3, characterized in that it further includes a dryer for drying the material, a vibrating screen for dividing the material into fractions, a vibrating mill for grinding a large fraction of the material.