JP4288649B2 - Vertical crusher - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vertical pulverizer that pulverizes raw materials such as cement raw materials, slag, clinker, ceramics, chemicals, and general inorganic / organic materials in cooperation with a rotary table and a pulverizing roller, and particularly improves the pulverization efficiency. The present invention relates to a vertical crusher intended for
[0002]
[Prior art]
As a type of pulverizer that finely pulverizes raw materials such as limestone, slag, and clinker into powder, a vertical pulverizer (shown in FIG. 4) having a rotary table and a pulverizing roller is widely used. This type of pulverizer is a disk-shaped rotary table that is driven by a motor through a speed reducer at the lower part of a cylindrical casing and rotates at a low speed, and a hydraulic pressure or the like is used to divide the outer peripheral portion of the upper surface in the circumferential direction. And a plurality of crushing rollers that are driven to rotate while being pressed against the rotary table.
[0003]
The crushing roller is connected to a piston rod of a hydraulic cylinder via an arm supported by a casing so as to be swingable by a shaft. By operating the hydraulic cylinder, the crushing roller is pressed onto the rotary table to be a raw material. Crushing pressure to give. The space between the inner surface of the casing and the blades of the rotary separator forms an annular passage for gas blowing around the rotary table. The material crushed by the blades of the rotary separator is classified and the product (fine powder) is discharged together with the gas. It is sent out to.
[0004]
In such a vertical crusher, the material to be crushed (raw material) supplied from the raw material supply pipe to the center of the rotary table rotates when the rotary table slides due to the centrifugal force in the table radial direction due to the rotation of the rotary table. The table receives a force in the rotating direction, slides between the rotating table and rotates somewhat slower than the rotating table. The above two forces, that is, the radial force and the rotational force are combined, and the object to be crushed moves on the rotary table to the outer periphery of the rotary table while drawing a spiral trajectory. Since the roller is pressed against this outer peripheral portion and rotated, the object to be crushed with a spiral wound enters between the pulverizing roller and the rotary table from a direction that forms an angle with the roller axial direction, and is caught. Rarely crushed.
[0005]
On the other hand, a gas such as air or hot air is guided to the base of the casing by a duct, and this gas blows up from an annular space passage between the outer peripheral surface of the rotary table and the inner peripheral surface of the casing, thereby crushing. The resulting fine powder is entrained by the gas and moves up in the casing, and is subjected to classification by the blades of the rotary separator located at the upper part. The product (fine powder) having a predetermined particle size is discharged from the discharge port together with the gas. Sent to the process.
[0006]
Next, an opportunity to pulverize the object to be crushed (raw material) newly supplied to the center of the rotary table will be described. The object to be crushed supplied near the center of the rotary table draws a spiral trajectory due to the centrifugal force of the rotary table and moves toward the outer periphery of the rotary table. Most of the other objects to be crushed pass through a dam ring that is provided around the outer periphery of the rotary table and are blown up by a high-speed airflow that falls to the outer annular space passage and rises up the annular space passage. Is returned to the rotary table again.
The majority of the material to be crushed supplied on the rotary table once overflows the rotary table and is repeatedly blown back onto the rotary table by the rising airflow. And discharged outside the mill. Therefore, there are few opportunities for the object to be crushed to be squeezed into the pulverizing roller, so that the efficiency of pulverization is low, and the dust concentration in the mill increases, and the suction fan is increased due to an increase in the mill differential pressure (also referred to as a pressure loss of gas flow). This has led to an increase in power, leading to an increase in running costs.
[0007]
[Problems to be solved by the invention]
In order to increase the pulverization efficiency of the newly supplied object to be crushed (mainly coarse particles), it is important to improve the pulverization opportunity of the newly supplied object to be pulverized. There are several techniques for improving the pulverization opportunity, such as those using an auxiliary roller and those that branch the raw material supply pipe and supply the material to the biting side of the roller. The invention of the present application comprises a hood for supplying raw material and a guide member for introducing the raw material supplied on the rotary table to the biting side of the pulverizing roller at the lower part of the raw material supply pipe located above the pulverizing table. The present invention relates to a technique for improving grinding efficiency.
Conventionally, the grinding opportunity and the load balance between the rollers have been balanced by the technical idea that the grinding raw material supplied to the center of the rotary table can be uniformly discharged in the circumferential direction. However, this method has many short passes of coarse particles (substance to be pulverized), leading to a decrease in pulverization efficiency and an increase in the amount of carrier gas.
[0008]
By having a hood for supplying raw materials and a guide member for introducing the material to be crushed supplied on the rotary table to the biting side of the pulverizing roller at the lower part of the raw material supply pipe located above the rotary table, an opportunity for pulverization is provided. There are the following two prior arts that have been improved. That is, Japanese Patent Laid-Open Nos. 61-174953 and 2-157050.
Japanese Patent Application Laid-Open No. 61-174953 discloses “a cylindrical stopper having a diameter close to a circle connecting the table rotation center to the innermost point of the roller (corresponding to the hood of the present invention), and an upper surface at the lower end of the cylindrical stopper. A circular platform with a diameter higher than that of the stopper and slightly smaller than the diameter of the stopper is set on the table to reduce the radial speed to zero, and then returned to the same diameter as the cylindrical stopper again and immediately below the cylindrical stopper. The spread of agglomerates that are swung out from the entire circumference of the table is induced as much as possible to the indentation of all the rollers arranged on the table.
Japanese Patent Laid-Open No. 2-157050 discloses that “a guide member is provided on a crushing table, and the guide member is provided in a spiral shape in a region inside the crushing roller from the center of the crushing table. A configuration is described in which the spiral direction from the inner side toward the outer side is opposite to the rotation direction of the grinding table.
[0009]
However, in the technique disclosed in Japanese Patent Application Laid-Open No. 61-174953, the agglomerated material (newly supplied material to be crushed) is swung out from the entire circumference on the table directly under the cylindrical stopper. Thus, although there is an effect of reducing the radial speed to zero, it is impossible to concentrate the agglomerates on the biting side of the grinding roller.
Further, the technique disclosed in Japanese Patent Application Laid-Open No. 2-157050 has a long residence time by a spiral guide member, and fine particles are introduced between coarse particles to increase the filling degree of the pulverized material. This is a technical idea for maintaining high grinding efficiency by balancing the purpose of preventing excitation vibration and the grinding roller. Therefore, considering the purpose of improving the pulverization opportunity of coarse particles (newly supplied crushed material), the crushed material that has been center chute is uniformly discharged in the circumferential direction, thereby balancing the pulverization opportunity and the roller. There is not much difference from the conventional method that was taking.
[0010]
[Means for Solving the Problems]
As mentioned above, the efficiency of biting the object to be crushed (raw material) into the grinding roller (crushing opportunity) is improved, the dust concentration in the mill is lowered, and the suction fan power can be reduced by reducing the mill differential pressure. Development of new technology was required.
In order to achieve the above object in the invention, in the first invention, the rotary table pivoted so that the upper surface is horizontal and driven to rotate about the vertical axis by the drive device, and directed to the rotary table. A raw material supply pipe for supplying the raw material, a plurality of crushing rollers driven to rotate as the rotary table arranged on the rotary table rotates, and a rotary separator for classification arranged at the top In addition, in a vertical crusher having an annular space passage that blows upward airflow around the periphery of the rotary table, a reverse cup in which main discharge ports formed by notches and auxiliary discharge ports without notches are alternately provided Rutotomoni provided Jo hood to the lower raw material supplying tube, and a configuration in which a spiral guide member between the boundary outside the main discharge port and the auxiliary discharge port to the front of the milling roller.
In the second invention, in the first invention, the outer diameter of the hood is in a range of 0.4 to 0.6 times the pulverizing table diameter, and the cutout range of the main discharge port is 20 to 20 in terms of a central angle. It was 75 degrees, and the notch height was in the range of 60 to 150 mm.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Initially, the structure of the solid pulverizer which concerns on one Embodiment of this invention is demonstrated based on FIGS. 1-3. FIG. 1 is a cross-sectional view of a pulverizing unit of a vertical pulverizer according to an embodiment of the present invention, and FIG. 2 is a hood and a guide disposed below a raw material supply pipe of the vertical pulverizer according to an embodiment of the present invention. FIG. 3 is an explanatory view of members, and FIG. 3 is an explanatory view of a trajectory along which a guide member fixed to a hood of a vertical crusher according to an embodiment of the present invention and a material to be crushed move.
In FIG. 1, the vertical crusher main body is provided with a raw material supply pipe 11 that penetrates the main body from the outside and introduces a raw material (a material to be crushed) into the pulverizer 1. A reverse cup-shaped hood 19 according to the present invention is fixed to the lower portion of the raw material supply pipe 11. The rotary table 12 is driven to rotate by the same driving device (not shown). A plurality of crushing rollers 13 are arranged on the outer periphery of the upper surface of the rotary table 12. Each of the rollers 13 is rotatably mounted around a shaft (not shown), and is pressed down on the upper surface of the rotary table 12 by a roller lowering device (not shown) around a fulcrum bearing (not shown) and is engaged with the rotary table 12. The material to be crushed is crushed and crushed.
[0012]
As shown in FIG. 2, the reverse cup-shaped hood 19 has a notch 21 formed in the main discharge port 14, and a notch size capable of discharging a newly supplied object to be crushed (mainly coarse particles). It has become.
Since the auxiliary discharge port 15 has a small gap with the rotary table 12 and the coarse particles 27 are difficult to be discharged, only a relatively small pulverized material (fine particles) 28 is discharged.
The coarse particles 27 discharged from the main discharge port 14 are introduced into the biting side of the crushing roller 13 and pulverized by a guide member (comprising a main plate 23 and an auxiliary plate 24) shown in FIG. The raw material pulverized by the pulverizing roller 13 is discharged to the outer peripheral portion of the rotary table 12 by centrifugal force.
A gas passage (annular space passage) 18 is formed between the outer periphery of the turntable 12 and the inside of the casing 17 main body (space), and communicates with the hot gas inlet by the hot gas passage below the turntable 12. Yes.
[0013]
FIG. 2 is an explanatory view of an inverted cup-shaped hood 19 disposed at the lower part of the raw material supply pipe 11 of the vertical crusher according to the embodiment of the present invention. As shown in FIG. 2, the main discharge port 14 in which the cylindrical outer peripheral surface of the inverted cup-shaped hood 19 is notched by a height δ is provided in the range of 20 to 75 degrees in the central angle. When this notch angle is smaller than 20 degrees, the main discharge port becomes narrow and the object to be crushed cannot be discharged smoothly. Further, if the notch angle is larger than 75 degrees, the pulverized raw material spreads over the entire pulverizing table, so that it is difficult to form a thick raw material layer. Further, the auxiliary discharge port 15 having no notch and the main discharge port 14 formed by the notch are alternately provided. As is apparent from FIGS. 2 and 3, there are as many main discharge ports 14 as the number of crushing rollers 13. Further, the notch range of the main discharge port 14 is limited to a range of 20 to 75 degrees in terms of the central angle, which shows the range per pulverizing roller. That is, even when there are two and three crushing rollers, the notch range is 20 to 75 degrees in the central angle.
[0014]
Next, the height δ of the notch 21 of the main discharge port 14 will be described. This notch height δ varies depending on the size of the pulverizer, the type of material (raw material) to be crushed, and the raw material size, and is a pulverizer having a table diameter of 1000 to 2000 mm with a relatively small raw material size. Δ is suitably 60 mm, and δ is suitably 150 mm for pulverizers having a table diameter of 3000 to 5000 mm and a relatively large raw material size.
[0015]
FIG. 3 shows a spiral shape installed between the outside of the boundary between the main discharge port 14 and the auxiliary discharge port 15 of the reverse cup-shaped hood 19 disposed in the lower part of the raw material supply pipe 11 and before the grinding roller. It is explanatory drawing of the attachment state of a guide member, and the movement locus | trajectory of to-be-ground material.
As shown in FIG. 3, the positional relationship of the notch of the main discharge port 14 with respect to the pulverizing roller 13 is provided in a range of 20 ° to 75 ° on the counter-rotation direction side from the position of 20 ° on the counter-rotation direction side with respect to the roller central axis. Therefore, when the notch range is set to 75 °, the root of the spiral of the guide member 20 may be on the side opposite to the rotation direction with respect to the position of the adjacent roller.
The mounting height of the inverted cup-shaped hood 19 (the height of the lower surface of the hood) is appropriately about 60 mm from the upper surface of the rotary table 12.
[0016]
Although most of the coarse particles 27 in the pulverized material flow out from the main discharge port 14, the lump (layer) of the coarse particles 27 discharged from the main discharge port 14 collapses as it proceeds in the outer peripheral direction of the turntable 12. If this collapse phenomenon is left as it is, the pulverized raw material layer discharged from the main discharge port 14 spreads over the entire rotary table before being bitten by the pulverizing roller 13, so that the raw material layer becomes thin and there are many short paths. As a result, the biting efficiency is reduced (reduction of pulverization opportunities). In order to prevent the collapse of the raw material layer, a guide member was attached as shown in FIG. By this guide member, the coarse particles 27 are caught in the crushing roller 13 in a state where a thick layer is formed. Guide members (comprising a main plate 23 and an auxiliary plate 24) are attached to both sides of the main outlet 14 of the inverted cup-shaped hood 19 as shown in FIG. This guide member is constituted by a pair of a long guide plate (main plate) 23 and a short guide plate (complement plate) 24. Considering that the guide member is worn during use, the liner 25 is preferably fixed to the guide member main body with a bolt 26 or the like at the contact portion (lower surface) with the object to be crushed. By doing so, when the liner 25 is worn due to aging, only the liner 25 can be replaced. Further, it may be devised so that it can be adjusted in the vertical direction according to the layer thickness of the raw material.
[0017]
【The invention's effect】
As is clear from the above description, in the first and second inventions, the object to be crushed is discharged from the notch (main discharge port) of the reverse cup-shaped hood part toward the biting side of the pulverizing roller. Therefore, the short path is eliminated, the pulverization efficiency is greatly improved , and guide members are arranged on both sides of the main discharge port so that the object to be crushed forms a thick layer and is introduced to the biting side of the pulverization roller. Therefore, further improvement in grinding efficiency can be expected. Further, the fine particles flow out toward the outer periphery of the rotary table from the auxiliary discharge port without a notch. Therefore, since the reduction to the rotary table by the coarse airflow is not required, the pressure loss of the gas flow is reduced. As a result, the power consumption of the fan can be greatly reduced, and the productivity is improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a crushing part of a vertical crusher according to an embodiment of the present invention.
FIG. 2 is an explanatory view of a hood and a guide member disposed at a lower part of a raw material supply pipe of a vertical crusher according to an embodiment of the present invention.
FIG. 3 is an explanatory view of a movement locus of a guide member and a material to be crushed fixed to a hood of a vertical crusher according to an embodiment of the present invention.
FIG. 4 is an overall longitudinal sectional view of a conventional solid grinder.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Solid pulverizer 10 Rotary separator 11 Raw material supply pipe 12 Rotary table 13 Grinding roller 14 Main discharge port 15 Supplementary discharge port 17 Casing 18 Annular space passage 19 Reverse cup-shaped hood (also simply referred to as hood)
21 Notch 23 Main plate 24 Supplementary plate 25 Liner 26 Bolt 27 Object to be crushed (coarse)
28 Objects to be crushed (fine particles)
δ Notch height

Claims (2)

A rotary table that is pivotally supported so that the upper surface is horizontal and is rotationally driven around a vertical axis by a driving device, a raw material supply pipe that supplies the raw material toward the rotary table, and a rotary disposed on the rotary table A casket comprising a plurality of grinding rollers driven to rotate as the table rotates, a rotary separator for classification disposed at the top, and an annular space passage for blowing up an ascending air current to the periphery of the rotary table in type pulverizer, Rutotomoni provided inverted cup-shaped hood provided alternately and formed main outlet and notch no auxiliary discharge port by notches in the lower raw material supply pipe, a main outlet accessory A vertical crusher characterized in that a spiral guide member is provided between the outside of the boundary of the discharge port and before the crushing roller . The outer diameter of the hood is in the range of 0.4 to 0.6 times the pulverizing table diameter, the notch range of the main discharge port is 20 to 75 degrees in the central angle, and the notch height is 60 to 60 degrees. The vertical crusher according to claim 1, wherein the vertical crusher is in a range of 150 mm.

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