JPH10323574A - Vertical pulverizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve milling capacity by providing a rotary separator arranged at the top of a vertical pulverizer with a rotor rotating around a vertical shaft and plural classifying blades arranged at equal intervals on the outer periphery of the rotor and fixing a disintegrating blade outside each classifying blade. SOLUTION: A pulverizer 100A for pulverizing limestone or the like to make it powder is provided with a turntable 3A and plural pulverizing rollers 4 and at the top of the pulverizer 100a, a rotary separator 13 for classifying the pulverized product after pulverizing is provided. In this case, outside the classifying blades 13A of the separator 13 each, disintegrating blades 13B are arranged by being branched from the classifying blades 13A. These disintegrating blades 13B are for separating collected fine particles in a dust containing gas into pieces by making the rising flow of the dust containing gas passing between the disintegrating blades 13B collide with them and each of them is formed of a smooth flat plate. The groups of coagulated particles are disintegrated by the disintegrating blades 13B and then, the disintegrated matter are introduced to the classifying blades 13A to allow the pulverized product to be classified into crude powder and fine powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separator which pulverizes raw materials such as cement raw materials, limestone, slag, clinker, ceramics and chemicals by cooperation of a rotary table and a pulverizing roller, and provides a pulverized product on a top. Classification in the vertical mill to obtain a powder product of the desired particle size,
In particular, the present invention relates to a vertical pulverizer provided with a function of breaking up agglomerated particles before the pulverized product is subjected to a classification action.

[0002]

2. Description of the Related Art As one type of a crusher for finely pulverizing raw materials such as limestone, cement raw materials, and slag into powder, FIG.
As shown in FIG. 1, a vertical pulverizer 1 having a rotary table, a pulverizing roller, and a rotary separator is widely used.
This type of pulverizer includes a disk-shaped rotary table 3A that is driven by an electric motor 2B by a speed reducer 2 and rotates at a low speed at a lower portion of a cylindrical casing 15, and a hydraulic pressure is applied to a portion that divides an outer peripheral portion of the upper surface in a circumferential direction. And a plurality of crushing rollers 4 that are driven to rotate by being pressed by the like, and a rotary separator 13 that classifies crushed products after crushing is provided at the top of the crusher.

The crushing roller 4 is connected to a piston rod 10 of a hydraulic cylinder 9 via an arm 7 pivotally supported by a shaft 6 on a casing 15. 4 is pressed onto the rotary table 3A to give a pulverizing pressure to the raw material. 3S is a dam ring for adjusting the thickness of the raw material layer provided on the outer peripheral edge of the rotary table 3A, 14 is an annular space passage for blowing up gas around the rotary table 3A, 14A is a gas supply path,
13 is a rotary separator for classifying the pulverized product by the classification blade 13A, 16 is a product together with gas (refined powder after classification)
, A feed chute 17 and a hot air duct 20.

In such a vertical pulverizer, the raw material supplied to the center of the rotary table 3A by the raw material charging chute 17 receives centrifugal force in the table radial direction by the rotation of the rotary table 3A, and moves on the rotary table 3A. When slipping, the rotation of the turntable 3A is performed somewhat slower than the rotation speed.
The above two forces, that is, the force in the radial direction and the force in the rotational direction are synthesized, and the raw material moves on the turntable 3A to the outer peripheral portion of the turntable 3A along a spiral locus. Since the crushing roller 4 is pressed and rotated on the rotary table 3A on this outer peripheral portion, the raw material depicting the spiral is in the roller axial direction between the crushing roller 4 and the rotary table 3A. It enters from an angled direction, is bitten, and is crushed.

On the other hand, a gas such as air or hot air is guided to the base of the casing 15 by a hot air duct 20, and the gas is introduced into an annular space between the outer peripheral surface of the turntable 3 A and the inner peripheral surface of the casing 15. The fine powder pulverized by blowing up from the passage 14 is supplied to the rotary table 3A.
Over the dam ring 3S at the outer peripheral end of the separator 13 and ascends in the casing 15 with the gas, undergoes the classification action by the classification blade 13A of the separator 13 located at the upper part, and the product having the predetermined particle size is discharged from the discharge port 16 together with the gas. And sent to the next step.

[0006]

However, such a conventional vertical pulverizer has the following technical problems. The pulverized product generated in the rotary table, the pulverizing roller, and the pulverizing unit for performing the pulverization of the raw material is transported by the separator along with the ascending airflow and undergoes the classifying action.
Individual fine particles of the pulverized product generated in the pulverizing section are sometimes transported to the separator as single fine particles.However, in most cases, the individual fine particles are attracted to each other by the static electricity charged during pulverization and aggregate. Wake up to coarse particles,
Aggregation occurs due to the effect of moisture brought into the vertical grinder together with the raw materials, and the state in which small-diameter fine particles adhere around the large-diameter particles or the state in which the same small-diameter fine particles are aggregated and integrated , Introduced into the separator. This agglomeration phenomenon becomes more conspicuous as the desired product particle size becomes finer. In recent years, the demand for the particle size of the pulverized product has increased, and in the pulverization of the ultra-fine pulverization region carried out in accordance therewith, the required agglomeration has already been required. It has become a major problem that the fine particles having reached the particle size are circulated in the mill due to the aggregation phenomenon and are not discharged from the mill system.

In this case, the aggregated aggregated particles are apparently treated as large-diameter particles when subjected to the classification by the separator, and are returned to the pulverizing section without passing through the separator. Table 1 shows the test results in which the classification results vary depending on the degree of humidity in the atmosphere. The numerical values are set to values indicating the particle size distribution measured by the light transmission method (wet dispersion method) and the wind sieving method. The value indicating the particle size is indicated by the classified diameter, and the air sieve method clearly shows a tendency that the degree of agglomeration increases according to the degree of humidity and the apparent particle size tends to be coarse. That is, in the air stream, unlike the case of the wet dispersion, the fine particles aggregate and apparently,
This indicates that the tendency is increased as the particles are classified as coarse particles and the humidity is higher. Similarly, even in an actual apparatus, the classification result greatly changes depending on the atmospheric humidity.

[0008]

[Table 1]

[0009] However, most of the individual fine particles constituting the aggregated aggregated particle group are fine particles crushed to a desired product particle size, and are originally separated from the crushing system of the vertical crusher and externally. If the aggregated particles cannot be easily separated from the pulverizing system, the following inconvenience occurs.

[0010] The dust content in the mill increases, the pressure loss in the mill increases, and the power of the suction fan increases. Since the repetitive classification operation of the powder and the granular material to the separator increases, the power of the separator increases. As a result of an increase in the amount of the circulating powder in the mill, the mill power (rotary table drive power) increases and the mill pulverizing ability decreases. From the above, the power consumption per unit weight of raw material increases. Because of the above-described problems, there has been a long-awaited need for a countermeasure for eliminating the aggregation of the pulverized product immediately before the classifying action and for achieving the classifying action of single particles as much as possible.

[0011]

In order to solve the above-mentioned problems, according to the present invention, in the first invention, a plurality of rotatable crushing rollers are arranged on an upper surface of an outer peripheral portion of a rotary table. A vertical type equipped with a rotary separator that applies a predetermined crushing pressure to the crushing roller to crush the raw material supplied to the center of the rotating table between the upper surface of the rotating table and the peripheral surface of the crushing roller, and classifies the crushed product at the top. In the crusher, the separator includes a rotor rotating about a vertical axis, a rotating means of the rotor, and a plurality of classifying blades arranged at equal intervals on the outer periphery of the rotor. ,
A crushing blade for crushing agglomerated powder particles among crushed products introduced into the separator by a gas transport from a lower crushing portion and subjected to a classification action was fixed.

Further, in the second invention, a plurality of rotatable crushing rollers are arranged on the upper surface of the outer peripheral portion of the rotary table, and the raw material supplied to the center of the rotary table is rotated by applying a predetermined crushing pressure to the crushing roller. In a vertical pulverizer equipped with a rotary separator for pulverizing between the table top surface and the peripheral surface of the pulverizing roller and classifying the pulverized product at the top, the separator is
A rotor rotating about a vertical axis, a rotating means for the rotor, and a plurality of classifying blades arranged at equal intervals on the outer periphery of the rotor are provided, and a high-speed rotation about the vertical axis is provided between the rotary table and the separator. A crushing device having a plurality of crushing rods arranged at equal intervals radially around the outer periphery of a rotatable rotor is provided.

In the third invention, the central portion of the crushing device of the second invention is formed in a hollow cylindrical body, and the crushing product introduced into the separator is moved outward by the classifying action of the separator blade of the separator. A plurality of collecting pipes are provided on the outer periphery of the separator to collect the coarse powder particles that have been repelled and to guide the falling through the hollow portion of the hollow cylindrical body to the center of the rotary table.

[0014]

In the present invention, in the first invention, a plurality of rotatable crushing rollers are arranged on the upper surface of an outer peripheral portion of a rotary table, and a raw material supplied to the center of the rotary table is supplied to a crushing roller by a predetermined method. Crushing between the upper surface of the rotary table and the peripheral surface of the crushing roller by applying the crushing pressure of the above, and a vertical crusher equipped with a rotary separator for classifying crushed products at the top, the separator rotates around a vertical axis. And a rotating means of the rotor, and a plurality of classifying blades arranged at equal intervals on the outer periphery of the rotor, and each of the classifying blades is introduced into the separator by gas transport from a lower pulverizing unit to the outside thereof. Among the pulverized products subjected to the classifying action, the crushing blades for crushing the agglomerated powder are fixed, so that the aggregated particles collide with the crushing blades immediately before being subjected to the classifying action, and individual Fine particles It is introduced into the classifying blades after being decomposed apart, because grinding product is classified exactly coarse and fine powder, milling the circulation is reduced considerably due to aggregation.

Further, in the second invention, a plurality of rotatable crushing rollers are arranged on the upper surface of the outer peripheral portion of the rotary table, and the raw material supplied to the center of the rotary table is rotated by applying a predetermined crushing pressure to the crushing roller. In a vertical pulverizer equipped with a rotary separator for pulverizing between the table top surface and the peripheral surface of the pulverizing roller and classifying the pulverized product at the top, the separator is
A rotor rotating about a vertical axis, a rotating means for the rotor, and a plurality of classifying blades arranged at equal intervals on the outer periphery of the rotor are provided, and a high-speed rotation about the vertical axis is provided between the rotary table and the separator. Because it is configured to have a crushing device in which a plurality of crushing rods are provided radially at equal intervals around the outer periphery of the rotatable rotor, the aggregated particles in the dust-containing gas on the way from the crushing section to the separator are: It collides with the crushing rod that rotates at high speed of the crusher, breaks it down into individual fine particles, and then introduces it into the classification blades, where the crushed product is accurately classified into coarse powder and fine powder. Internal circulation is greatly reduced.

Further, in the third invention, the central portion of the crushing device of the second invention is formed in a hollow cylindrical body, and the crushed product introduced into the separator is moved outward by the classification action of the separator blade of the separator. A plurality of collecting pipes that collect the coarse powder particles that have been repelled and are guided through the hollow portion of the hollow cylindrical body and fall to the center of the rotary table are arranged on the outer periphery of the separator, so that they are sorted by the classifying action. The coarse powder that needs to be reground is returned to the rotary table and reground without passing through the rotating crushing rod of the crusher, so that the updraft is not disturbed. Thus, a more stable gas flow in the mill is formed, and the continuous stable operation is continued.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 9 relate to an embodiment of the present invention,
FIG. 1 is an overall vertical sectional view of a vertical mill, FIGS. 2 to 4 are schematic vertical sectional views of main parts of a separator showing another embodiment, FIG. 7 is a vertical sectional view of a main part of the crushing apparatus of FIG. 5, FIG. 7 is a side view of a crushing apparatus showing another embodiment, FIG. 8 is a plan view taken along AA of FIG. FIG. 10 is a comparison diagram of a conventional machine and an improved machine based on the present invention regarding the correlation between the mill differential pressure and the unit power of the mill and the amount of pulverization.

In the vertical pulverizer 1A of the present invention, as shown in FIG. 1, a crushing blade 13B for crushing the aggregated fine particles is provided outside the classification blade 13A of the separator 13 so as to be branched from the classification blade 13A. . Classification blade 13A generally has a cross section L
In contrast to using a trapezoidal angle steel bent in a V-shape, for example, the crushing blade 13A rotates the crushing blade 13B due to a dust-containing gas rising airflow that passes between the crushing blades without the main purpose of classification. The main purpose is to cause the aggregated particles in the dust-containing gas to collide with each other and separate (crush) the particles into fine particles. However, in order to maintain the rigidity of the crushing blade 13B, a trapezoidal angle steel may be used similarly to the classification blade 13A.

FIGS. 2 to 4 show the crushing blade 13B.
Another embodiment of the separator 13 having
In the embodiment of FIG. 2, the crushing blade 1 is placed on an extension of the lower cone 13 a which is the rotor of the separator 13 along the bottom surface of the cone.
3B was provided. In the embodiment shown in FIG.
In FIG. 4, the crushing blade 13B is arranged at the classifying blade position of the conventional machine, and the classifying blade 13A is vertically arranged inside the classifying blade 13B. Was placed.

FIG. 5 shows a crusher 5 corresponding to the second invention.
In this example, a crushing device 50 is provided between the crushing unit and the separator 13 in place of the crushing blade 13B of the separator 13. As shown in FIGS. 5 and 6, the detailed structure of the crusher 50 is such that the horizontal output shaft 50e of the variable speed motor 60 disposed outside the casing 15 is guided into the mill via the speed reducer 70, and A horizontal crushing rod 50 that is converted around the vertical axis by the engagement of the bevel gears 50c and 50d in the 50b and rotates at high speed around the vertical axis in the mill.
The crushing rods 50a are formed of a column or a flat plate having a rectangular cross section, and a plurality of crushing rods 50a are radially disposed at equal circumferential intervals.

In the crushing apparatus shown in FIG. 5, the gear box 50b of the crushing apparatus 50 is disposed at the center of the mill. It could not be adopted, so the material input chute 1
Numeral 7 employs a side feed system for supplying the raw material obliquely downward to the side of the casing 15.

If it is desired to supply the raw material with properties or a uniform raw material supply on the rotary table, a crushing apparatus 50 according to another embodiment shown in FIGS.
A (corresponding to the third invention) is adopted. This crusher 50A is designed so that a center feed method can be adopted.
The crushing device 50 is formed such that the shaft portion is hollow, and a girth gear (large gear) 50i is attached via a bearing 50h to the outer periphery of a hollow cylindrical body 50g fixed to a stand 50f. Similarly to the crusher 50, the horizontal output shaft 50e of the variable speed motor 60 disposed outside the casing 15 is guided into the mill via the speed reducer 70, and the gearbox 50
By rotating the pinion gear (small gear) 50j that meshes with the girth gear 50i by converting it around the vertical axis by the meshing of the bevel gears 50c and 50d in FIG. It was configured to rotate at high speed. In this case, since the raw material charging chute 17 can be guided into the cylindrical body 50g, center feeding is possible.

As shown in FIG. 7 and FIG. 8, on the outside of the classifying blade 13A of the separator 13, coarse powder having a classification point (classified particle size) higher than the classifying point (classified particle size) excluded by the classifying blade 13A is collected. About two to six coarse powder conduits 80 to be guided and dropped at the center of 3A are arranged at equal circumferential intervals. The opposing portion of the classifying blade 13A of the coarse powder conduit 80 is a pipe in a half-split state, or as shown in FIG. Uses a pipe formed in a cylindrical shape. The lower end of the coarse powder conduit 80 is connected to the side wall of the cylindrical body 50g, and the coarse powder classified by the separator 13 is returned to the center of the rotary table for re-grinding without crossing the crushing rod 50a.
The updraft in the mill is not disturbed, the change in pressure loss in the mill is small, the generation of vibration is minimized, and stable continuous operation can be continued.

FIG. 10 shows a crushing blade 13A provided when a crushing test is carried out by a tester (rotary table diameter: 360 mm) of a vertical crusher having a separator 13 provided with the crushing blade 13A of the present invention. It is a graph comparing the classification performance with the conventional test machine without, according to the results, clearly the improved machine of the present invention, which classifies after destruction of aggregated aggregated fine particles, has a different mill differential pressure, As shown in Table 2, it was found that, in addition to the mill differential pressure and the mill power consumption unit, the milling power was excellent as well as the power consumption rate was improved and other test results.

[0025]

[Table 2]

As described above, in the vertical pulverizer of the present invention, the aggregated fine particles are destroyed by the presence of the crushing blades 13B and the crushing rods 50a of the crushing devices 50 and 50A, and the individual fine particles are broken down. Classifier blades 13A that fall apart
As a result, the mill pressure loss (mill differential pressure) decreases, the suction fan power and the mill drive power can be reduced, and the mill capacity increases. The mill power, suction fan power, and separator power are integrated. A large reduction of the total power consumption unit achieved is achieved.

[0027]

As described above, in the present invention, the following excellent effects can be exhibited. (1) By installing a crushing blade or a crushing rod having an extremely simple structure, the differential pressure of the mill is reduced, the power of the suction fan is reduced, and the power for driving the mill can be reduced. (2) The yield of the refined powder having a desired particle size is improved. (3) The mill capacity is improved and the power consumption is significantly reduced.

[Brief description of the drawings]

FIG. 1 is an overall vertical sectional view of a vertical crusher according to an embodiment of the present invention.

FIG. 2 is a schematic vertical sectional view of a main part of a separator according to an embodiment of the present invention.

FIG. 3 is a schematic vertical sectional view of a main part of a separator according to an embodiment of the present invention.

FIG. 4 is a schematic vertical sectional view of a main part of a separator according to an embodiment of the present invention.

FIG. 5 is a longitudinal sectional view of a main part of the crushing apparatus according to the embodiment of the present invention.

FIG. 6 is a longitudinal sectional view of a main part of the crusher of FIG.

FIG. 7 is a side view of a crusher according to another embodiment of the present invention.

FIG. 8 is a plan view taken along line AA of FIG. 7;

FIG. 9 is an enlarged longitudinal sectional view of a main part of the crushing device of FIG.

FIG. 10 is a comparison diagram of a conventional machine and an improved machine based on the present invention with respect to the correlation between the mill differential pressure and the unit power of the mill and the grinding amount.

FIG. 11 is a vertical sectional view of a conventional vertical crusher.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vertical grinder (conventional) 1A Vertical grinder (this invention) 2 Reduction gear 2B Electric motor (Electric motor for driving a rotary table) 3A Rotary table 3S Dam ring 4 Crush roller 4a Rotary shaft 5 Arm 6 shaft (rotary shaft) 7 Arm 13 Separator 13A Classifying blade 13B Crushing blade 13a Lower cone 14 Annular space passage 15 Casing 17 Raw material charging chute 20 Hot air duct 50 Crushing device 50a Crushing bar 50b Gear box 50c Bevel gear 50d Bevel gear 50e Output shaft 50f Stand 50g Cylindrical body 50 Bearing 50i Girth gear 50j Pinion gear 60 Variable speed motor 70 Reduction gear 80 Coarse powder conduit

Claims (3)

[Claims] 1. A plurality of rotatable crushing rollers are arranged on an upper surface of an outer peripheral portion of a rotary table, and a raw material supplied to a center portion of the rotary table is applied with a predetermined crushing pressure to the crushing roller so that the upper surface of the rotary table and a crushing roller are circulated. A vertical separator having a rotatable separator for pulverizing between the surfaces and classifying the pulverized product at the top, wherein the separator comprises a rotor rotating about a vertical axis, a rotating means of the rotor, and an outer periphery of the rotor. A plurality of classifying blades arranged at equal intervals, and, outside each of the classifying blades, of the pulverized products introduced into the separator by a gas transport from a lower pulverizing unit and subjected to a classifying action, and agglomerated. A vertical pulverizer in which crushing blades for crushing powders are fixed. 2. A plurality of rotatable crushing rollers are arranged on an upper surface of an outer peripheral portion of a rotary table, and a predetermined crushing pressure is applied to a crushing roller for a raw material supplied to a center portion of the rotating table, and the upper surface of the rotating table and a crushing roller are provided. A vertical separator having a rotatable separator for pulverizing between the surfaces and classifying the pulverized product at the top, wherein the separator comprises a rotor rotating about a vertical axis, a rotating means of the rotor, and an outer periphery of the rotor. A plurality of crushing rods are provided radially at equal intervals on the outer periphery of a rotor that is rotatable at high speed around a vertical axis, between the rotary table and the separator. A vertical crusher comprising a crushing device provided around the crusher. 3. A central portion of the crushing device is formed in a hollow cylindrical body, and coarse powder particles repelled outward by a classifying action of a classifying blade of the separator among crushed products introduced into the separator are collected. 3. The vertical pulverizer according to claim 2, wherein a plurality of collecting pipes are provided on the outer periphery of the separator so as to guide the fall through the hollow portion of the hollow cylindrical body to the center of the rotary table.