JP2681853B2 - Crushing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crushing facility for raw materials of various chemical products such as cement clinker and blast furnace slag, which is efficiently crushed by a vertical crusher and a ball mill, consumes less power, and immediately responds to load fluctuations. Regarding crushing equipment that can be used.

[0002]

2. Description of the Related Art Conventionally, a ball mill has been used as a crushing facility for crushing chemicals such as cement clinker and blast furnace slab. For example, as shown in FIG. 6, the raw material of the hopper 100 is cut out by a constant feed wear 200. ，
It is supplied to the ball mill 1000, and the pulverized product is pneumatically conveyed to the cyclone separator 1100 by an extraction fan 1300 (1200 is an air volume control valve), classified by the cyclone separator 1100, and the coarse powder is returned to the ball mill 1000 via the circulation path 1400 to be recycled. It is crushed and only fine powder is taken out as a product, which is produced by a so-called closed circuit operation. In this case, the ball mill 100
Ball mill 1000 has 2
It is necessary to divide into more than one chamber and grind with a grinding medium (ball) with a large diameter to a small diameter one by one, which not only complicates the structure of the ball mill but also has a drawback that the grinding power is large.

On the other hand, a vertical crusher 1 having a higher crushing efficiency than a ball mill and suitable for producing a relatively coarse product is used as a preliminary crusher. For example, the crushing equipment shown in FIG. In this case, the raw material of the hopper 100 is supplied to the vertical crusher 1 by the constant feed wear 200, all the crushed products are discharged and supplied to the ball mill 1000 for secondary crushing. 2
The powder particles after the subsequent pulverization are conveyed to the cyclone separator 1100 via the transporter 300, and after being classified, the coarse powder is returned to the ball mill 1000 to be re-pulverized, and the fine powder is collected by the dust collector 600 to be a product. 700 is an air volume control valve,
800 is an extraction fan. The crushing equipment of FIG. 7 also operates in a closed circuit as in FIG. 6, but the ball mill 1000 needs only one chamber for preliminarily crushing the raw material, and the equipment cost of the ball mill itself is low, but it is a vertical crusher as a preliminary crusher. Since the machine 1 is required, the total equipment cost is higher than that of FIG. 6, but there is an advantage that the running cost is low.

[0004]

In the conventional crushing equipment using only the ball mill, the ball mill is divided into two or more chambers, and it is necessary to perform the two-step crushing by changing the diameter of the ball as the crushing medium, which complicates the structure. Not only increases equipment costs but also consumes a large amount of electricity, which is a basic unit of electric power (kwh / t)
However, it was difficult to efficiently pulverize. Further, as shown in FIG. 7, in the pulverizing equipment that uses the vertical pulverizer as the preliminary pulverizer and the ball mill as the finishing pulverizer,
Although it has an energy saving effect compared to the ball mill only, the whole amount of the crushed products from the vertical crusher is put into the ball mill, so even the fine powder that has already reached the final product particle size by crushing with the vertical crusher can be used in the ball mill. As a result, the powder is subjected to the crushing action in the above, and it becomes over-crushed and is mixed into the final product, which causes problems in terms of the crushing efficiency and the quality of the final product. Furthermore, in the crushing equipment that crushes by connecting the vertical crusher and the ball mill, when the load of the ball mill fluctuates and the load of the ball mill becomes excessive or, on the contrary, becomes too small, It was difficult to control the flow of raw materials in good balance by controlling the discharge amount of the die crusher.

[0005]

[Means for Solving the Problems] In order to solve the above-mentioned problems and to obtain a crushing facility which can respond to the load fluctuation of the crusher, can perform stable continuous operation, and has a low running cost, In the equipment, a raw material transporting equipment consisting of a raw material hopper and constant feed wear, a vertical crusher, a transporter for the powder and granules discharged from the lower part of the vertical crusher, and the vertical and vertical powder A circulation route for returning to the crusher, a fine powder route for transferring the fine powder discharged from the top of the vertical pulverizer by air transfer to the dust collector, a dust collector, a suction fan and an air flow control valve for the suction fan, and a dust collector A ball mill for supplying and crushing the collected fine powder, an air separator for classifying crushed products of the ball mill, and a circulation path for returning the coarse powder after classification of the air separator to the ball mill,
A crushing facility comprising an extraction fan and an air flow control valve for the extraction fan, wherein an operation command is issued to the air flow control valve of the suction fan when the operation power value of the ball mill exceeds a preset value, and the air flow rate is increased. It is configured to include a control device for changing the.

[0006]

In the crushing equipment of the present invention, when the load on the ball mill fluctuates and, for example, the load suddenly increases, an electric signal of the indicated value of the wattmeter of the electric motor for driving the ball mill is sent to the control device in advance. When this value is compared with the set upper limit value and the value exceeds this value, the controller sends a command signal to decrease the opening degree to the air volume control valve installed upstream of the suction fan according to the degree, and the suction air volume decreases. As a result, the amount of fine powder discharged from the vertical pulverizer flowing through the fine powder path is reduced, and as a result, the amount of raw material supplied to the ball mill is reduced and the overloaded state of the ball mill is eliminated. On the contrary, when the load of the ball mill is too low and the electric power value is lower than the lower limit value input in advance to the control device, the suction fan air volume is increased and the feed material to the ball mill is increased.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The crushing equipment of the present invention will be described in detail below with reference to the drawings. 1 to 5 show an embodiment according to the present invention, FIG. 1 is a flow sheet of a crushing equipment, FIG. 2 is a control system diagram of the crushing equipment, FIG. 3 is a block diagram of a control device, and FIG. 4 is vertical crushing. FIG. 5 is a vertical sectional view of an essential part of the vertical crusher. In the figure, 100 is a raw material hopper, 20
0 is constant feed wear, 1 is a vertical crusher,
300 is a transportation machine such as a bucket elevator, 400 is a circulation path connecting the transportation machine 300 and the vertical crusher 1, and a normal belt conveyor or chute is used. 500 is a fine powder path, 600 is a dust collector, 700 is an air flow control valve, 80
0 is a suction fan, 1000 is a ball mill, 1100 is a cyclone separator, 1200 is an air volume control valve, 1300.
Is an extraction fan, and 1400 is a circulation path. Also, 20
00 is a control device connected to the driving motor 1000a of the ball mill 1000 and the drive unit of the air volume control valve 700, and 60 is a pressure gauge 60 attached to each vertical crusher 1.
The control device 210 is a differential pressure gauge that measures the pressure difference between a and 60b.
0 is connected to the controller of the variable speed electric motor 200a of the constant feed wear 200.

The vertical crusher 1 used in the crushing equipment of the present invention is, as shown in FIG. 4, a disk-shaped rotation which is driven at a low speed by a speed reducer 2 by a motor 2A in a lower portion of a cylindrical casing 15. The table 3A is provided with a plurality of crushing rollers 4 which are pressed against each other by hydraulic pressure or the like and are driven to rotate at locations where the outer peripheral portion of the upper surface is equally divided in the circumferential direction. The crushing roller 4 is connected to a piston rod 10 of a hydraulic cylinder 9 via an arm 5 and an arm 7 which are swingably supported by a shaft 15 on a casing 15, and by operating the hydraulic cylinder 9, 4 turntable 3A
It is pressed upwards to give crushing pressure to the raw material. 3B is a dam ring provided on the outer peripheral edge of the rotary table 3A for adjusting the raw material layer pressure, 14 is an annular space passage around the rotary table 3A, 15a is a top plate of the casing 15, 16 is a gas discharge port for taking out the product together with gas, Reference numeral 17 is a raw material charging chute. Further, reference numerals 60a and 60b are pressure gauges attached to pressure detection ports in the vertical crusher 1.

In such a vertical crusher, the raw material supplied to the central portion of the rotary table by the raw material feeding chute 17 receives the centrifugal force in the radial direction of the rotary table 3A and slides on the rotary table 3A. Sometimes the rotary table 3A receives a force in the direction of rotation,
A slides with A and makes a rotation somewhat slower than the rotation speed of the turntable 3A. 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 is
A moves to the outer periphery of the turntable 3A in a spiral locus on A. Since a roller is pressed against this outer peripheral portion and rotated, the raw material describing the spiral enters the crushing roller 4 and the rotary table 3A from a direction forming an angle with the roller axis direction and is caught. Rarely crushed.

On the other hand, the duct 1 is provided at the base of the casing 15.
A gas such as air or hot air is introduced by 4A, and this gas is blown up from the annular space passage 14 between the outer peripheral surface of the rotary table 3A and the inner peripheral surface of the casing 15 to pulverize the fine powder. Is entrained in the gas and rises in the casing 15, and the granular material having a predetermined particle size is discharged from the discharge port 16 together with the gas and sent to the next step.

Further, as shown in FIG. 5, the rotary table 3
Below the outer periphery of A, a discharge chute 40 for collecting and discharging the raw materials that have overflowed the rotary table 3A and dropped into the annular space passage 14 to the outside of the machine, is conveyed by the belt conveyor 50. 40a is a scraper attached to the rotary table 3A.

The operation of the vertical crusher 1 of the present invention having the above-described structure will be described. The raw material supplied from the raw material charging chute 17 spirally moves toward the outer peripheral side by the centrifugal force of the rotating rotary table 3A, and is caught between the crushing roller 4 and the rotary table 3A to be crushed. Particles of the raw material which have passed between the crushing rollers overflow the dam ring 3B and overflow the rotary table 3A, but the fine powder is moved upward in the annular space passage 14 by the ascending air current and the top plate 1
5a, and air is conveyed from the discharge port 16 to the outside of the machine.
On the other hand, the coarse particles that have been inverted by gravity in the middle are returned to the rotary table again, and are caught by the next crushing table 3A located downstream in the rotation direction and crushed. Also, the annular space passage 1
The coarse particles having a relatively large particle size that have overcome the rising air flow and have fallen due to gravity in 4 are scraped by the scraper 40a and conveyed to the outside of the machine by the belt conveyor 50 via the discharge chute 40, or Direct discharge chute 40
Is transferred to the downstream transport machine 300.

Next, the operation of the crushing equipment of the present invention will be described. The material of hopper 100 is constant feed
It is cut out by the wear 200, supplied to the vertical crusher 1 and crushed, and the coarse particles are transported by the transport machine 300 and the circulation path 400.
And is pulverized again by the vertical pulverizer 1. The pulverized fine powder passes through the fine powder path 500 together with the gas guided to the suction fan 800, is collected by the dust collector 600, is then supplied to the ball mill 1000, and is secondarily pulverized. The pulverized powder enters the air separator 1100 along with the air flowing through the outlet of the ball mill by the extraction fan 1300, and the coarse powder after the classification passes through the circulation path 1400 and the ball mill 10 again.
The fine powder after classification is collected into a product by being subjected to a crushing action in 00. Since all of the fine powder of the vertical crusher 1 becomes the feed material for the ball mill 1000, the classification point is made coarser than the case where only the vertical crusher is used as the final product, and most of the coarse particles are circulated externally. The vertical air crusher has about 10% upflow as compared with the vertical crusher (internal circulation method in which the total amount is discharged as fine powder after classification by the built-in vertical crusher separator)
Keep it to a low level. As a guide, the limit particle size discharged by air conveyance is about 3 mm.

In the crushing equipment of the present invention, the vertical crusher 1 and the ball mill 1000 are connected in series, and an overload of the vertical crusher 1 can be dealt with by immediately reducing the raw material supply amount. In the case where the ball mill 1000 is overloaded due to load fluctuations, there is a time lag even if the amount of raw material supplied to the vertical crusher is reduced, and it is not suitable for emergency situations. Therefore, the following control is performed in the crushing equipment of the present invention. As shown in FIG. 2, when the load of the ball mill 1000 changes, for example, when an overload occurs, the power value for driving the ball mill (k that changes every moment as a means for catching the overloaded state)
w value) is adopted. That is, the measured value of the power measured moment by moment is transmitted to the control device 2000. Control device 2000
As shown in FIG. 3, the measurement result of the electric power value measured at every time interval set by the timer is converted into an electric signal and input to the control device 2000, and this information (ball mill driving (The electric power value of the electric motor for driving) is compared with the upper and lower set values inputted in advance to the setter, and if the set value is out of the range, the air flow control in front of the suction fan 800 is performed via the controller. The valve opening of the valve 700 is controlled to change the ventilation amount of the vertical crusher. The controller is composed of a controller and a controller. The controller indicates the range of the rate of change of the valve opening according to the difference between the measured value and the set value, and the control operation is proportional to the operation (P Motion), integral motion (I motion), differential motion (D motion), proportional integral motion (PI)
Motion), proportional differential motion (PD motion), etc., depending on the frequency and degree of load fluctuation of the ball mill.
Based on the instructions from this controller, the controller controls the air volume control valve 7
The operation command is transmitted to 00. The line with the arrow in the figure indicates the signal flow. In this way, the ball mill 1000
Is overloaded, the air flow control valve 700 changes its opening degree in the closing direction according to the degree of overload, and as a result, the ventilation volume of the vertical crusher 1 decreases, and as a result, the dust collected by the dust collector 600 is collected. And the ball mill supply is reduced and ball mill overload is improved. On the contrary, even when the load of the ball mill is below a certain limit, the supply amount of the ball mill increases and this state is improved.

When the load fluctuation of the ball mill 1000 deviates from the set limit range as described above, the supply amount to the ball mill 1000 is changed, and the operating state of the vertical crusher 1 must be changed accordingly. That is, the pressure difference between the upper and lower ends of the vertical crusher 1 is detected by the differential pressure gauge 60, and the constant pressure wear 200 is detected through the control device 2100 having the same function as the control device 2000 described above.
It is possible to properly control the operating state of the vertical crusher 1 in response to load fluctuations of the ball mill by controlling and changing the supply amount of. The controller 2100 can be substituted with the controller 2000.

By performing the automatic control having the feedback mechanism as described above, when the load of the ball mill suddenly increases or, conversely, when the load becomes light and there is a surplus in the operation, the automatic operation described above is performed. In addition to being able to immediately return to the original stable operating condition, the crushing efficiency is improved because the crusher is used for the rated time. In addition, the diameter of the ball mill grinding media can be reduced, and the reduction ratio (grinding ratio) is reduced, improving the ball mill's performance.

[0017]

As is apparent from the above description, in the crushing equipment of the present invention, the original stable operation is restored by automatically increasing or decreasing the supply amount in response to the load fluctuation of the ball mill. The operability is improved, the ball mill capacity is improved, and the grinding efficiency is improved. Also,
The particle size of the raw material supplied to the ball mill, which is the secondary crusher, can be controlled by the amount of air blown into the vertical crusher, which is the primary crusher (preliminary crusher), so over-crushing of the final product can be prevented and the desired particle size can be achieved. The final product of the composition is easy to obtain.

[Brief description of the drawings]

FIG. 1 is a flow sheet of a crushing facility according to an embodiment of the present invention.

FIG. 2 is a control system diagram of the crushing equipment according to the embodiment of the present invention.

FIG. 3 is a block diagram of a control device for a crushing facility according to an embodiment of the present invention.

FIG. 4 is an overall vertical sectional view of a vertical crusher according to an embodiment of the present invention.

FIG. 5 is a longitudinal sectional view of a main part of a vertical crusher according to an embodiment of the present invention.

FIG. 6 is a flow sheet of a conventional crushing facility.

FIG. 7 is a flow sheet of a conventional crushing facility.

[Explanation of symbols]

 1 Vertical grinding machine 3A Rotary table 4 Grinding roller 40 Discharging chute 40a Scraper 50 Belt conveyor 60 Differential pressure gauge 60a Pressure gauge 60b Pressure gauge 100 Raw material hopper 200 Constant feed wear 200a Variable speed electric motor 300 Transport machine 400 Circulation path 500 Fine powder path 600 Dust collector 700 Air volume control valve 800 Suction fan 1000 Ball mill 1000a Electric motor 1100 Air separator 1200 Air volume control valve 1300 Extraction fan 1400 Circulation path 2000 Controller 2100 Controller

Claims (1)

(57) [Claims] 1. A raw material transportation facility comprising a raw material hopper and a constant feed wear, a vertical crusher, a powder feeder for discharging powder particles from the lower portion of the vertical crusher, and the powder particles. A circulation path for returning to the vertical crusher, a fine powder path for transferring fine powder discharged from the top of the vertical crusher by air transfer to a dust collector, a dust collector, a suction fan, and an air flow control valve for the suction fan, and the dust collector A ball mill for supplying and pulverizing the fine powder collected in step 1, an air separator for classifying the pulverized product of the ball mill, a circulation path for returning the coarse powder after classification of the air separator to the ball mill, an extraction fan and an extraction fan A flow rate control valve for changing the flow rate of the suction fan when the operation power value of the ball mill exceeds a preset value. Crushing equipment equipped with a control device.