JP3570265B2 - Crusher - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The pulverizing apparatus of the present invention relates to a pulverizing apparatus for efficiently pulverizing raw materials such as cement clinker, cement raw material, coal, limestone, slag, ceramics, filler, and chemicals into products having a predetermined particle size. And a pulverizing apparatus suitable for pulverization by two-stage pulverization by a tube mill.
[0002]
[Prior art]
Conventionally, when pulverizing raw materials such as cement clinker, cement raw material, coal, limestone, and slag, a vertical roller mill (also referred to as a mill device or a mill) or a tube mill is used. In recent years, from the viewpoint of energy saving, raw materials are coarsely pulverized (hereinafter sometimes referred to as primary pulverization) with a vertical roller mill having high coarse pulverization efficiency, and the coarsely pulverized raw materials are reduced in fine pulverization efficiency. A two-stage pulverizer that performs fine pulverization with a good tube mill (hereinafter sometimes referred to as secondary pulverization) is preferably used.
[0003]
In particular, in the case of a two-stage crusher using a tube mill as a secondary crusher, if the maximum particle size of the raw material supplied to the tube mill is reduced, the balls in the tube mill can be reduced in diameter. Since the crushing efficiency can be greatly improved, the operating power of the entire crusher can be greatly reduced.
[0004]
The vertical roller mill used as a primary crusher is a type in which most of the crushed raw material is dropped from the outer peripheral surface of the crushing table and the inner peripheral surface of the casing to the outside of the mill and taken out (referred to as a mill lower take-out type). And a type in which the entire amount of the raw material pulverized by the gas introduced into the mill from the pulverizing table and the case is blown up and taken out together with the gas from above the mill device (also referred to as a mill upper extraction type or an air sweep type). Although the vertical roller mill of the upper take-out type can suppress the maximum particle size of the crushed product to about 500 μm and improve the crushing efficiency of the tube mill as a secondary crusher, the crushed product is blown up. A large amount of gas and a high wind pressure are required to transport the gas, and the operating power of the fan for blowing the gas becomes extremely large. From the viewpoint of energy saving, raw materials of the mill mills downwardly takeout type need not be transported blown upward by the gas vertical roller mill is increasingly being used.
[0005]
However, in the vertical roller mill of the mill take-out type, the supplied raw material may be taken out of the mill as it is because of its structure, and the maximum particle size of the pulverized product exceeds 10 mm. When a pulverized product having a maximum particle size of 10 mm or more is pulverized by a tube mill, the pulverization efficiency of the tube mill is deteriorated.
For this reason, when using a vertical roller mill of the lower take-out type as the primary pulverizer, the pulverized product pulverized by the vertical roller mill of the lower take-off type is classified by a classifier, and the pulverized product is reduced to a certain particle size or less. A method has been considered in which only a product is pulverized as a fine powder by a tube mill, and a pulverized product that does not become smaller than a certain particle size is coarsely pulverized again by a vertical roller mill.
[0006]
[Problems to be solved by the invention]
However, when a sieve-type classifier is used as a classifier in the pulverizer, if the size of the sieve is reduced to reduce the maximum particle size of the primary pulverized product, the size of the sieve becomes clogged or worn. However, the maximum particle size of the primary pulverized product cannot be reduced as desired.
[0007]
In addition, when a centrifugal classification type classification device equipped with a rotating distribution plate is used, a power source such as a motor for rotating the distribution plate is required inside the classification device, and the structure is complicated, and the rotating part inside the classification device is worn. Problems such as are likely to occur.
[0008]
The present invention has been made in view of the above-mentioned problems of the conventional pulverizer, and has a tube mill as a secondary pulverizer, which has a simple structure and is capable of reliably performing classification and an efficient classifier. It is an object of the present invention to obtain a pulverizer having a classifier capable of separating and sorting particles having a small diameter to such an extent that the pulverization efficiency can be sufficiently increased.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the crushing device of the present invention comprises:
(1) Between a crushing table that rotates horizontally in a casing, a crushing table that is pressed against the upper surface of the crushing table and rotates horizontally in a driven rotary casing, and a crushing roller that is pressed against the upper surface of the crushing table and driven to rotate. A vertical roller mill configured to pulverize the raw material, drop substantially all of the pulverized product from the outer peripheral surface of the pulverizing table to the inner peripheral surface of the casing, and take out the raw material under the vertical roller mill; and grinding of the vertical roller mill. A classifier for separating the product into coarse powder and fine powder, means for returning the coarse powder separated and separated by the classifier to the vertical roller mill, and fine powder separated and separated by the classifier are supplied. Crusher consisting of a tube mill
The classification device has a classification gas inlet for introducing a classification gas, a gas outlet for taking out the gas after classification, and an inertial classification type including a pulverized product introduction port for introducing a pulverized product taken out of a vertical roller mill. Or gravity classifier classifier The classification gas introduced from the classification gas inlet of the classification device is not separated from the gas by the classification device as a gas at least part of which is discharged as dust-containing gas from the vertical roller mill. The crushed product is discharged together with the gas as a dust-containing gas from a gas outlet, and the dust-containing gas is supplied to a dust collector, and the crushed product contained in the dust-containing gas is collected by the dust collector. Supplies to the tube mill Configuration.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings. 1 to 5 show an embodiment according to the pulverizing apparatus of the present invention, FIG. 1 is a flow sheet of the pulverizing apparatus, FIG. 2 is a conceptual diagram of the behavior of powder in a louver-type inertial classification apparatus according to the pulverizing apparatus, FIG. Is a flow sheet of a pulverizer according to the second embodiment, FIG. 4 is a conceptual diagram of the behavior of powder in a zigzag classifier used in the second embodiment, and FIG. 5 is a longitudinal sectional view of a vertical roller mill.
[0015]
A pulverizing device according to an embodiment of the present invention will be described with reference to FIGS. 1, 2, and 5. FIG.
The vertical roller mill 1 used in the embodiment of the present invention includes a pulverizing table 32 that can be rotated by a drive source (not shown), and a pulverizing roller that is pressed by the pulverizing table 32 via a raw material and is rotated by the rotation of the pulverizing table 32. 31, a roller pressing hydraulic device 38 for pressing the crushing roller against the crushing table 32, a material input port 35 for supplying a raw material to the crushing table 32, and a crushed product crushed by the crushing roller 31 and the crushing table 32. An annular passage DF, which is a passage for taking out outside the roller mill 1, and a lower outlet 34 are provided.
[0016]
The raw material (cement clinker in the present embodiment) supplied from the raw material hopper 60 to the vertical roller mill 1 is passed through a raw material input port 35 of the vertical roller mill 1 through a raw material input chute 37 provided at the upper center of the pulverizing table 32. It is thrown into the central part of the crushing table 32 from above.
The input raw material is rotated on the crushing table 32, and is moved to the outer peripheral portion of the crushing table 32 while drawing a spiral trajectory on the crushing table 32 by the generation of centrifugal force due to the rotation. It is caught and pulverized between the table 32 and the pulverizing roller 31 pressed in the direction of the pulverizing table 32 by the roller pressing device 36.
[0017]
The raw material (sometimes referred to as a pulverized product) that is bitten by the pulverizing table 32 and the pulverizing roller 31 reaches the outer edge of the pulverizing table 32, and a dam ring 38 is provided on the outer peripheral edge of the pulverizing table 32. It is fixed and provided.
Therefore, the pulverized product that has reached the outer edge of the pulverizing table 32 is stopped by the dam ring 38 and stays on the pulverizing table 32 while maintaining a predetermined layer thickness. And may be crushed or get over the dam ring 38.
[0018]
Then, the pulverized product having passed over the dam ring 38 is discharged into the annular passage DF between the outer peripheral surface of the pulverizing table 32 and the inner peripheral surface of the casing. Gas flows upward in the mill from the annular passage DF between the outer peripheral surface of the crushing table 32 and the inner peripheral surface of the casing, and has a small particle size in the pulverized product discharged into the annular passage DF. The raw material is carried upward in the mill by the gas flow, and is taken out from the upper outlet 39 of the vertical roller mill 1 together with the gas as dust-containing gas.
[0019]
Further, the raw material having a small particle diameter contained in the pulverized product and floating on the table in the mill is carried upward in the mill by a gas flow, and is fed from the upper outlet 39 of the vertical roller mill 1. It is extracted as dust-containing gas together with the gas.
[0020]
The amount of the pulverized product extracted as dust-containing gas from the upper outlet 39 of the vertical roller mill 1 is very small (2 to 5% in the present embodiment), and substantially the pulverized product discharged to the annular passage DF. The entire amount falls to the outside of the mill below the annular passage DF between the outer peripheral surface of the crushing table 32 and the inner peripheral surface of the casing, and is taken out of the mill through the lower outlet 34.
[0021]
The pulverized product taken out from the lower outlet 34 of the vertical roller mill 1 is conveyed through a bucket elevator 41, and is a louver-type inertial classifier 2 (a louver-type classifier 2) which is an inertial classifier classifier described in detail later. ) May be supplied to the raw material supply port 2B.
Further, the dust-containing gas taken out from the upper outlet 39 of the vertical roller mill 1 is sent as a classification gas to the gas inlet 2A of the louver type classification device 2 (also referred to as supply), and the gas is introduced at the same time. A classification gas other than the dust-containing gas is also introduced from the port 2J.
[0022]
As shown in FIG. 2, the louver-type classification device 2 includes a louver-type slit 2 </ b> F formed by arranging a plurality of blades 2 </ b> G in parallel at intervals, and the gas flow passing through the slit 2 </ b> F Of the pulverized products formed and supplied to the louver type classification device 2, the pulverized products that have passed through the slit together with the gas are taken out as fine powder, and the pulverized products that cannot pass through the slit are taken out as coarse powder. .
[0023]
In the present embodiment, the coarse powder falls downward without passing through the louver-type slit 2F, and is taken out from a coarse-powder outlet 2C disposed below the louver-type classifier 2, and is supplied to the raw material inlet of the vertical roller mill 1. It is returned to 35 and crushed again.
The crushed product having a relatively large diameter in the fine powder having passed through the slit 2F together with the gas is separated from the gas immediately after passing through the slit 2F and falls down below the apparatus. It is taken out from the outlet 2D, fed to the tube mill 10, and subjected to secondary pulverization.
[0024]
Further, since the pulverized product having a relatively small diameter (sometimes referred to as fine powder) in the fine powder does not separate from the gas even after passing through the slit 2F, it is taken out as a dust-containing gas from the gas outlet 2E, It is sent to a bag filter 45 which is a dust collector.
Then, the fine powder contained in the dust-containing gas is collected, sent to the tube mill 10, and subjected to secondary pulverization.
[0025]
In this embodiment, by using at least the gas discharged as dust-containing gas from the vertical roller mill 1 as the classification gas of the classification device, a pulverized product contained in the dust-containing gas from the vertical roller mill can be used. The pulverized product contained in the dust-containing gas can be efficiently collected at once by the bag filter 45 in the classification device.
[0026]
Generally, as the maximum particle size of the pulverized product supplied to the tube mill 10 is larger, it is necessary to arrange a large-diameter pulverizing ball in the pulverizing chamber of the tube mill 10. It is known that the crushing efficiency of the region is deteriorated.
The tube mill 10 used in the present embodiment includes a primary pulverizing chamber and a secondary pulverizing chamber. The primary pulverizing chamber is provided with a pulverizing ball having a diameter corresponding to a supplied pulverized product. Provided a small-diameter crushing ball according to the particle size of the product, but if the maximum particle size of the raw material supplied to the tube mill 10 is large, it is necessary to provide a large-diameter crushing ball in the primary grinding chamber. And the grinding efficiency was poor.
[0027]
In the embodiment of the present invention, the maximum particle size of the raw material to be fed to the tube mill 10 as the secondary pulverizer using the louver type classification device 2 is set to 2.5 mm or less (about 1 mm). The ball diameter of the primary crushing chamber 10 can be changed from 90 to 40 mm to 40 to 25 mm, and the crushing efficiency (unit power consumption) and crushing capacity (throughput) of the tube mill 10 are greatly improved. be able to.
[0028]
The pulverized product pulverized and taken out by the tube mill 10 is sent to a classification device 53 via a bucket elevator 42 to be classified, and those having a predetermined particle size or less are sorted and separated as products. The pulverized product that has not been converted into a product by the classification device (air separator) 53 is returned to the tube mill 10 again and pulverized again.
[0029]
Further, gas is blown into the tube mill 10 in order to remove the pulverized product of the fine particles in the tube mill 10, and the fine particles in the tube mill 10 are conveyed by the gas stream and taken out from the tube mill 10. I have.
However, the pulverized product taken out by the gas flow contains not only fine particles but also a small amount of large particles, so the pulverized product taken out is fed to the classification device 52 to be classified. Then, only a raw material having a predetermined particle size or less as a product is taken out as a fine powder, and collected by a collector 43 composed of an air separator or the like to obtain a product.
The coarse powder classified by the classification device 52 and not sent to the collector 43 is returned to the tube mill 10 again and pulverized.
[0030]
In the present embodiment, the coarse powder that has been classified by the classifying device 52 and not sent to the collector 43 is classified again by the classifying device 53 and put into the tube mill 10 for convenience of transporting the raw material. Coarse powder that has been classified by the classifier 52 and not sent to the collector 43 may be directly returned to the tube mill 10 and pulverized.
[0031]
In this embodiment, a normal temperature gas is used. However, when the raw material is dried at the same time as the pulverization, a hot gas such as air is used as the gas used in the vertical roller mill 1, the tube mill 10, the louver classifier 2, and the like. Of course, it is also possible to use.
[0032]
Hereinafter, the details of the louver type classification device 2 will be described with reference to FIG.
The louver classifier 2 according to the present embodiment is formed so as to be surrounded by a casing 2H, and a plurality of blades 2G are arranged (arranged) at predetermined intervals in a substantially central portion of the casing 2H in a diagonal up-down direction, and the whole is a louver. It is formed as a mold slit 2F (sometimes referred to as a slit 2F). The slit 2F is attached so as to partition the casing 2H into two portions on both left and right sides.
The gas inlet 2A and the gas inlet 2J are arranged side by side on the side of the casing 2H on one side of the louver-type slit 2F, and the gas inlet 2A is provided on the side of the casing 2H on the other side. A gas outlet 2E is attached to face 2J.
Further, a raw material supply port 2B is arranged above the upper end of the slit 2F on the upper surface of the casing 2H.
[0033]
A coarse powder outlet 2C is disposed below the gas inlets 2A and 2J of the casing 2H partitioned by the slit 2F, and is provided at a gas outlet 2E side of the casing 2H partitioned by the slit 2F. A fine powder outlet 2D is provided below.
[0034]
In the present embodiment, as shown in FIG. 2, the louver-type slit 2F is formed by a plurality of blade plates 2G arranged in a line at substantially equal intervals in a diagonal up-down direction. The blades 2G are made rotatable by attaching a shaft to the section and supporting the shaft with a bearing disposed on the casing 2H.
One or both of the shafts attached to both ends of the blade plate 2G are inserted through the holes of the bearing and protrude outside the casing 2H. The blade plate is rotated by rotating the protruded shaft. The angle of 2G is adjusted, and the degree of opening / closing of the slit 2F formed by the blade plate 2G (opening / closing state or opening degree) is freely adjustable.
[0035]
Further, in order to adjust the opening / closing state of the slit 2F, the gas flow passes through the slit 2F by adjusting the angle of the blade 2G so as to reduce the gap between the blade 2G and the blade 2G. When the flow direction is greatly changed, the particle size of the pulverized product that can pass through the slit 2F becomes small, and the gas flow flows through the slit 2F by increasing the gap between the blades 2G. If the flowing direction is not largely changed when passing, the particle size of the pulverized product that can pass through the slit 2F becomes large. Therefore, in the embodiment of the present invention, as described above, the pulverized product outside the casing 2H is used. By rotating the protruding shaft, the open / close state of the slit 2F can be freely changed, and the classification performance can be freely controlled even during operation.
[0036]
Therefore, if the particle size distribution of the pulverized product supplied to the louver type classification device 2 changes, etc., the pulverized product having the same particle size cannot be separated as fine powder while the opening degree of the slit 2F is kept constant, or In the embodiment of the present invention, even when it is desired to change the particle size or amount of the fine powder supplied to the tube mill due to different pulverizability of the pulverized product, the opening degree of the slit 2F is freely changed. Among them, classification according to the situation can be performed, and the pulverized product can be separated and sorted into coarse powder and fine powder having a desired particle size.
[0037]
The classification process of the louver classifier 2 having the above configuration will be described below. The pulverized product taken out from the lower outlet 34 of the vertical roller mill 1 is conveyed and lifted by the bucket elevator 41 and supplied to the louver type classification device 2 through the pulverized product supply port 2B, and is supplied to the slit 2F. It falls on the wing board 2G arranged at the upper part.
[0038]
As shown in FIG. 2, the blade 2G is inclined so as to descend toward the gas inlets 2A and 2J, so that the pulverized product dropped on the blade 2G is moved along the inclination of the blade 2G. 2A and 2J, the gas flow is directed from the gas inlets 2A and 2J and discharged from the gas outlet 2E and flows through the inside of the blade 2G. Yes,
Therefore, the pulverized product that has fallen on the blade plate 2G joins and collides with the gas flow, so that the small-diameter pulverized product is carried by the gas current and does not fall on the blade plate 2G but is inclined. Passes along the gap between the blade plate 2G and the blade plate 2G, and passes through the slit 2F. However, even if the pulverized product having a large diameter that is not entrained by the gas flow even when it merges with the gas flow and collides with the gas flow, It falls along the slope toward the gas inlets 2A and 2J.
[0039]
The large-diameter crushed product that has fallen in the direction of the gas inlets 2A and 2J along the inclination of the blade plate 2G falls on the next blade plate 2G disposed therebelow and is similarly classified again. Therefore, the pulverized product is repeatedly subjected to the classifying action by the number of times corresponding to the number of the blades up to the blade 2G disposed at the lower end of the slit 2F.
The pulverized product having a large diameter that falls to the end even after being subjected to the repetitive classification action is taken out as coarse powder from the coarse powder outlet 2C.
[0040]
Further, the gas flow path narrowed at the slit 2F is expanded by passing through the slit 2F, so that the gas flow velocity immediately after passing through the slit 2F is smaller than the gas flow velocity at the slit 2F. For this reason, most of the pulverized product having a small diameter that has passed through the slit 2F, immediately after passing through the slit 2F, falls below the louver-type classification device 2 and is disposed in the lower portion of the louver-type classification device 2. Although it is taken out as fine powder from the outlet 2D, it is a crushed product having a relatively small diameter among the crushed products that have passed through the slit 2F, and is taken out as fine powder without falling below the louver type classification device 2. The pulverized product which did not exist is taken out of the gas passing through the slit as dust-containing gas from the gas outlet 2E, collected by a dust collector described below, and taken out as fine powder.
The louver classifier 2 according to the present embodiment can classify the pulverized product by supplying gas only as far as the pulverized product having a small diameter to be taken out as fine powder passes through the slit 2F. Therefore, a large amount of gas is required for classification. Classification can be performed with less energy.
[0041]
In the present embodiment, even if the particle size of the raw material taken out of the vertical roller mill 1 changes due to a change in conditions such as the type and amount of the raw material charged into the vertical roller mill 1 during operation, the slit 2F can be used. By changing and adjusting the open / close state and the air volume, pulverized products having a maximum diameter of 1 mm or less can be selectively separated and supplied to the tube mill 10 as fine powder.
In addition, by using the louver-type classifier 2, the raw material having a maximum particle size of 2.5 mm or less is always stably and efficiently separated as fine powder with a simple facility without increasing the pressure loss. By setting the maximum particle size of the raw material fed to the tube mill 10 to 2.5 mm or less (about 1 mm), the ball diameter of the primary grinding chamber of the tube mill 10 is conventionally 90 to 40 mm. , 40 to 25 mm, and it is possible to greatly improve the crushing efficiency (unit of electric power) and crushing capacity (processing amount) of the tube mill 10.
[0042]
Next, another embodiment (sometimes referred to as a second embodiment) according to the present invention will be described below with reference to FIGS.
In the second embodiment, a zigzag classifier 20 which is a gravity classifier classifier is used as the flow sheet crusher shown in FIG.
[0043]
Details of the zigzag classification device 20 will be described below.
The zigzag classifier 20 used in the second embodiment is formed by a cylindrical casing 20H that extends in a vertical direction while bending in a zigzag shape as shown in FIG. 4, and the casing 20H is branched into two at the upper part. One of the upper ends of the two branched casings 20H is opened upward to form a raw material supply port 20B, and the other upper end is opened upward to form a gas outlet 20E. are doing. The lower portion communicates with the classifying gas chamber 20K formed by being divided by the inclined dispersing plate / coarse powder supplementary plate 20J and the upper surface of the dispersing plate / coarse powder supplementary plate 20J, and is provided with a coarse powder outlet 20C. ing.
[0044]
The casing 20H is a gas passage through which a classification gas can flow from the gas inlet 20A at the lower end to the gas outlet 20E at the upper end, and the classification gas flowing upward from the gas inlet 20A. , A gas flow that rises in the gas passage from the gas inlet 20A to the gas outlet 20E can be formed.
[0045]
In the second embodiment, as in the first embodiment, at least the gas discharged as dust-containing gas from the vertical roller mill 1 is used as a classification gas, and the dust-containing gas and, if necessary, classification other than the dust-containing gas. The gas and the gas are introduced together through the gas inlet 20A.
Thus, the pulverized product contained in the dust-containing gas from the vertical roller mill and the pulverized product contained in the dust-containing gas in the classification device are efficiently collected at once by the bag filter 45.
[0046]
In the second embodiment, the pulverized product taken out from the lower outlet 34 of the vertical roller mill 1 in the same manner as in the above-described embodiment (sometimes referred to as the first embodiment) is supplied through the raw material supply port 20B. Then, the gas is supplied into the zigzag classifier 20, and the gas is introduced above the gas inlet 20A arranged at the lower part of the casing 20H.
Then, among the pulverized products supplied from the supply port 20B of the raw material, the fine powder having a small diameter rises through the gas passage together with the gas, passes through the gas passage, and is taken out as a dust-containing gas from the gas outlet 20E at the upper end, The coarse powder having a large diameter cannot rise and pass through the gas passage together with the rising gas flow, but falls downward and is taken out from the coarse powder outlet 20C.
[0047]
Note that the zigzag classifier 20 used in the second embodiment bends the gas passage to make a zigzag shape and changes the direction of the gas flow to the left and right, and also allows the pulverized product that rises with the gas to the inner wall of the casing 20H. By the collision, the mixing and separation of the pulverized product and the gas are repeated to improve the classification accuracy.
[0048]
The dust-containing gas is sent to a bag filter 45, which is a dust collector, and the fine powder contained in the dust-containing gas is collected, sent to a tube mill 10 and secondary pulverized, and falls downward to collect coarse powder. The coarse powder taken out from the outlet 2C is returned to the raw material input port 35 of the vertical roller mill 1 and pulverized again, and thereafter processed in the same manner as in the first embodiment to become a product.
[0049]
In the second embodiment, the maximum particle size of the raw material to be fed to the tube mill 10 as the secondary pulverizer as in the first embodiment using a very simple structure such as a zigzag classifier 20 is used. 2.5 mm or less, the crushing efficiency (power consumption) and crushing capacity (processing amount) of the tube mill 10 as a secondary crusher can be greatly improved to achieve high production, and the efficiency of the entire crushing apparatus can be achieved. Can be greatly improved.
Further, the zigzag classification device 20 is a device having a very simple structure, and can perform stable operation without any failure.
[0050]
As described above, in the first and second embodiments, the case where the cement clinker is crushed has been described.However, if the crushing device of the present invention is used, not only the cement clinker but also the cement raw material, coal, limestone, slag, ceramics, filler In addition, raw materials such as chemicals can be efficiently pulverized into products having a predetermined particle size according to the above principle.
[0051]
【The invention's effect】
As explained above, in the crushing device of the present invention,
In the first invention, a pulverized product primarily pulverized by a vertical roller mill is separated and separated into coarse powder and fine powder by a classifier, and the coarse powder is pulverized again by a vertical roller mill, and the fine powder is mixed with a tube. In a pulverizing device for secondary pulverization by a mill, the classifying device is an inertial classification type or a gravity classification type classification device, so that the primary pulverized product having a desired particle size can be efficiently and stably obtained with simple equipment. Powder and coarse powder can be separated and separated, and the efficiency of the pulverizer can be improved.
[0052]
Also, By using a louver-type inertial classifier as the classifier of the inertial classification type, for example, by changing the conditions such as the type and amount of the raw material charged into the vertical roller mill during operation, the raw material taken out from the vertical roller mill Even if the particle size changes, a pulverized product having a stable particle size can be selectively separated and supplied to a tube mill by changing and adjusting the opening / closing state of the slit and the air volume. In addition, the louver-type classification device has simple equipment and small pressure loss, so that the pulverized product can be constantly and efficiently separated and separated as fine powder, and the efficiency of the pulverization device can be improved.
[0053]
Also, By using a zigzag classifier as the gravity classifier classifier, with a simple facility, and efficiently, it is possible to always stably separate and separate the raw material of the desired particle size as fine powder, a pulverizer Efficiency can be improved.
[0054]
Furthermore, in the present invention By sending the dust-containing gas taken out from the classifying device to the dust collector, the dust-collecting device can efficiently collect the pulverized product contained in the dust-containing gas. be able to.
[0055]
Also, By using the gas discharged as dust-containing gas from the vertical roller mill as the classification gas introduced from the classification gas inlet of the classification device, the pulverized product contained in the dust-containing gas from the vertical roller mill and Since the pulverized product contained in the dust-containing gas can be efficiently collected at once by the dust collector in the classifier, the pulverizer can be operated efficiently.
[Brief description of the drawings]
FIG. 1 is a flow sheet of a crusher according to an embodiment of the present invention.
FIG. 2 is a conceptual diagram of powder behavior in a louver-type classification device according to a pulverizing device of an embodiment of the present invention.
FIG. 3 is a flow sheet of a crusher according to a second embodiment of the present invention.
FIG. 4 is a conceptual diagram of a behavior of powder in a zigzag classification device according to a grinding device of a second embodiment of the present invention.
FIG. 5 is a longitudinal sectional view of a vertical roller mill according to the embodiment of the present invention.
[Explanation of symbols]
1 vertical roller mill
2 Louver type inertial classifier
2A gas inlet
2B raw material supply port
2C coarse powder outlet
2D fine powder outlet
2E Gas outlet
2F Louver type slit
2G blade
2H casing
2J gas inlet
10 Tube mill
17 Material input chute
17a Material input port
20A gas inlet
20B Raw material supply port
20C coarse powder outlet
20E gas outlet
20H casing
20J Dispersion plate and coarse powder supplement plate
20K classification gas chamber
31 grinding roller
32 crushing table
33 Gas inlet
34 Lower outlet
35 Raw material inlet
39 Upper outlet
43 Collector
45 Bag Filter (Dust Collector)
52 classifier
53 classifier

Claims (1)

Crushing the raw material between a crushing table that rotates horizontally in the casing and a crushing roller that is pressed against and driven by the top of the crushing table, and substantially the entire amount of the crushed product is formed on the outer peripheral surface of the crushing table and the inner peripheral surface of the casing. Between the vertical roller mill and the vertical roller mill, and a classifier for separating and separating the pulverized product of the vertical roller mill into coarse powder and fine powder. Means for returning the coarse powder to the vertical roller mill again, and a crusher comprising a tube mill to which the fine powder separated and separated by the classifier is supplied,
The classification device has a classification gas inlet for introducing a classification gas, a gas outlet for taking out the gas after classification, and an inertial classification type including a pulverized product introduction port for introducing a pulverized product taken out of a vertical roller mill. Or a gravity classifier classifier ,
The classification gas introduced from the classification gas inlet of the classification device is at least a part of the gas discharged as dust-containing gas from the vertical roller mill,
By the classifier, the pulverized product that is not separated from the gas is discharged as a dust-containing gas together with the gas from a gas outlet, and the dust-containing gas is sent to a dust collector and is contained in the dust-containing gas by the dust collector. A pulverizing device for collecting pulverized products and supplying the collected products to a tube mill.

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