RU2264864C1 - Sequential grinding method - Google Patents

Abstract

FIELD: rock grinding method.

SUBSTANCE: method involves preliminarily sorting materials into fractions; feeding large-sized fractions onto first working tool into maximal impact pulse zone; imparting impact pulse to each individual portion of material to be ground; forming diverging flows of particles under grinding process at different velocities; directing high-velocity particles of central part of said flow to first working tools and imparting second impact pulse thereto, with vectors of reflected particles being focused at point of space, wherein collisions are provided with counter flow of high-velocity particles of next portion of material to be ground, said next portion being ejected by first working tool; imparting to particles with low-velocities of peripheral parts of flow of first portion impact pulses by means of second working tools by directing particles to be ground to third working tools; imparting to particles directed to first working tool additional impact pulse; withdrawing ready product; directing non-ground large-sized particles for repeated grinding cycle.

EFFECT: improved property of grinding, reduced power consumption and decreased wear of equipment.

1 dwg

Description

The invention relates to crushing methods and can be used in mining, construction, chemical and other industries.

Known methods of impact crushing [1]. For example, a method involving the destruction of material by counter-directed pulses of the working body and reflective elements [2]. In this case, the directed pulses of the reflecting elements are synchronized with the pulses of the working body, and their shock surface is oriented normal to the particle velocity vectors directed to the working bodies, while the speed of movement of the reflecting elements is 0.3 ... 3.5 of the speed of the working body. Obviously, in the event of an oncoming active impact, the instantaneous impact power sharply increases in comparison with a strike on jack-off fixed plates. The energy applied in microseconds forms fields and waves of stresses of a supercritical level, significantly exceeding the tensile strength of all types of rocks.

However, the aforementioned method requires large energy costs and leads to significant wear of the working bodies.

A known method of combined impact crushing [3], including the destruction of the material by counter-directed pulses of the working bodies, synchronized with each other so that the directions of motion of the particles communicated by the working bodies during the initial impact are oriented relative to each other at an angle of at least 45 °, the impact surface reflective elements are oriented normal to the resulting direction of the momentum acquired by the pieces of rock after the collision, and shock pulses from the reflective elements are oriented with respect to additional reflective elements, it is opposite along the same axis to ensure a counter collision of particles reflected from the reflective elements, while particles from impulses transmitted by them intersecting at one point form a counter collision zone - the working zone of rocks, and for a predominant collision equivalent the magnitude of the momentum of the pieces of rock in the working area is primarily ensured by the collision of rocks after the initial impact from symmetrically located working bodies on the one hand, and undamaged particles moving from reflective elements, on the other hand. Moreover, the rotation of the working bodies and reflective elements with respect to each other is regulated in phase and number of revolutions, ensuring their alternation in the working area.

Compared to the previous one, this method has the advantage that a part of the crushed material is involved in the self-crushing process due to the oncoming collision. However, a large part of the mass of the substance is simultaneously involved in the crushing, and the method itself assumes the presence of a complex energy-intensive design.

The objective of the proposed method is to improve the quality of crushing, reducing energy consumption and wear of equipment.

To solve this problem, a method of sequential crushing is proposed, including the destruction of crushed material by multiple shock pulses of the working bodies. In this case, the crushed material is pre-sorted into fractions, the largest of which are fed to the first working body in the zone of maximum shock impulse, and each individual portion of crushed material is given a shock impulse, a diverging flow of crushed particles with different speeds is formed, high-speed particles of the central part of the flow are directed to the second working bodies located at the moment of collision with these particles at a distance L from the zone of maximum shock impulse of the first working body, we can determine ratio

L = V _h · T,

where V _h is the average particle velocity of the Central part of the stream, m / s,

T is the period between the pulses of the first working body, s;

and tell them a second shock pulse, while the vectors of the reflected particles are focused at a point A of the space located at a distance of 0.3 ... 0.6 L between the first and second working bodies above the first working body, in which mutual collisions with the oncoming flow of high-speed particles of the next portion of crushed material, which is thrown by the first working body, and particles with low speeds of the peripheral parts of crushing, of the first portion, are given shock pulses by the second working bodies, directing crushed particles to third The organs that direct them towards each other at point A, where they are crushed together, give an additional shock impulse to the crushed particles that have fallen from the area of point A to the first working body, the finished product is selected, and non-fragmented particles of large fractions are sent for re crushing cycle.

The drawing shows the phases of the device according to the claimed method.

The method is divided into several stages.

Stage 1. Sorting material by fractions.

Stage 2. The supply of large fractions in the zone of maximum shock impulse.

Stage 3. Communication of the shock pulse of the first portion of crushed material and the formation of a diverging flow of crushed particles in the direction of the second working bodies.

Stage 4. Separation of the flow into parts.

Stage 5. Reflection of the central part of the stream with the message of a shock pulse to it and focusing it to point A for a collision with a second portion of crushed material.

Stage 6. Communication of the shock pulse to the peripheral parts of the flow and their direction to the third working bodies.

Stage 7. Reflection of crushed particles from third working bodies and their direction to point A for their mutual crushing.

Step 8. Message dropping crushed particles from the region of point A of the shock pulse by the first working body.

Step 9. The selection of crushed material and the return of uncrushed material to a repeated cycle.

Consider the implementation of the proposed method on the example of a rotary crusher, consisting of the first working body - the lower rotor and synchronously connected with it by the second working bodies - the second and third rotors, on both sides of which reflective baffle plates are installed.

Due to the fact that the first rotor has different linear speeds along the length of the blade, the edge of the rotor will have maximum speed, forming a zone of maximum shock impulse. The largest pieces are served in it. Small ones are distributed at smaller radii. When striking a piece of crushed material, they break it into a portion of smaller parts, which are fan-shaped flow directed towards the second working bodies located at a distance defined by the expression

L = V _h · T,

where V _h is the average particle velocity of the Central part of the stream, m / s,

T is the period between pulses, s.

The advantages of the proposed method is that the crushing of large pieces of rock occurs first and foremost with a maximum shock pulse, and then there is a crushing of smaller fractions with a smaller shock pulse. As a result, the composition of the crushed rock is equalized and losses due to excessive crushing of fine fractions are reduced and, as a result, waste is reduced.

Further, the portions of crushed materials are divided into parts with a lower mass depending on their speed of movement, and the moments of their crushing are distributed more evenly throughout the process cycle, which also contributes to the alignment of the composition and suggests that the crusher works more uniformly. Reduced wear on working elements, as part of the crushed material is crushed due to ordered self-crushing.

Sources of information

1. Klushantsev B.V. and others. Crushers. M .: Engineering, 1990.

2. RF patent No. 2029616, 1989. Method of impact crushing.

3. RF patent No. 2111056, 1996. The method of combined impact crushing. (prototype).

Claims (1)

A method of successive crushing, including the destruction of the crushed material by multiple shock pulses of the working bodies, characterized in that the crushed material is pre-sorted into fractions, the largest of which are fed to the first working body in the zone of maximum shock pulse, with each individual portion of crushed material reporting a shock pulse form a diverging stream of crushed particles with different speeds, high-speed particles of the central part of the stream are sent to the first working devices Ghana located at the moment of collision with these particles at a distance L from the zone of maximum shock impulse of the first working body, determined by the ratio L = V _h · T, where V _h is the average particle velocity of the central part of the stream, m / s;  T is the period between the pulses of the first working body, s, and give them a second shock pulse, while the vectors of the reflected particles are focused at a point A of the space located at a distance of 0.3 ... 0.6 L between the first and second working bodies above the first working body, in which they produce mutual collisions with the oncoming flow high-speed particles of the next portion of crushed material, which is thrown by the first working body, and particles with low speeds of the peripheral parts of the flow of the first portion are given shock pulses by the second working bodies, directing crushed particles to the third working parts e organs that direct particles towards each other to point A, where they are crushed together, and an additional shock impulse is given to crushed particles that have fallen from the area of point A to the first working body, the finished product is selected, and non-fragmented particles of large fractions are sent to re crushing cycle.