JP2015044150A - Vertical mill, and method for operating vertical mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vertical mill preferable for efficiently pulverizing a raw material with an in-machine atmosphere uniformed, and to provide a method for operating the vertical mill.SOLUTION: A vertical mill that pulverizes a raw material between a rotary table and a pulverization roller and blows it up with a gas supplied into the machine from below the rotary table to take it out, comprises: a plurality of gas supply ports to supply a hot gas into the machine to define one of the gas supply ports as a first gas supply port, and another one of the gas supply ports as a second gas supply port with a discharge chute set adjacent; and temperature measurement instruments arranged above the first and second gas supply ports, respectively. A supply amount of an adjustment gas is so controlled that temperatures of gases from the first and second gas supply ports may be the same by arranging a flow control mechanism to control the supply amount of an adjustment gas, in an adjustment gas supply port.

Description

  The present invention relates to the field of pulverization of raw materials, and a vertical pulverizer and vertical pulverizer suitable for pulverizing cement raw materials, slag, clinker, limestone, coal, and other inorganic raw materials, and organic raw materials containing biomass. Relates to the driving method.

Conventionally, a crusher called a vertical crusher (sometimes referred to as a vertical mill or a vertical roller mill) has been widely used as a crusher for crushing coal or the like.
The vertical crusher has not only the excellent characteristic that it can efficiently crush the object to be crushed (sometimes simply referred to as a raw material in the present specification), but also, for example, It has an excellent feature that the raw material is pulverized and dried simultaneously by introducing gas or the like.

  In addition, when drying a raw material with a vertical mill, it is known that the temperature control of the gas supplied into the vertical mill is important. For example, in Patent Document 1 below, By mixing air and cold air, the temperature of the air supplied into the vertical crusher is controlled.

JP-A-62-276317

  By the way, in recent years, there is an increasing need for an increase in the size of a vertical crusher, and many manufacturers of vertical crushers have increased the diameter of the rotary table and the crushing roller in response to the increase in size. In order to cope with an increase in the number of pulverizing rollers and the like, and to make the atmosphere in the larger machine uniform, for example, an ingenuity is made with respect to the installation position of the gas supply port.

  Here, FIG. 6 shows an arrangement example of gas supply ports (sometimes referred to as gas ducts) as the number of rollers increases. When the vertical pulverizer is increased in size, it is preferable that gas is supplied at a uniform temperature from a plurality of gas supply ports in order to ensure the uniformity of the gas atmosphere in the enlarged pulverizer.

  This is because, if gases with different temperatures are supplied from a plurality of gas supply ports at a plurality of locations, the raw material properties (humidity state, etc.) on the rotary table depend on the position where the gas is placed. As a result, there is a risk that stable operation becomes difficult because the state of raw material biting by a plurality of crushing rollers becomes different depending on the position of each crushing roller. For reasons.

  Further, if the raw material is continuously pulverized while the biting state is different during operation in each of the plurality of pulverizing rollers, the degree of progress of wear differs among the respective pulverizing rollers. Usually, the crushing rollers change all the crushing rollers at the same time in accordance with the replacement timing of the most worn crushing rollers. Therefore, if the degree of progress of wear differs between the grinding rollers, the grinding roller that is not worn enough to be replaced is also changed in accordance with the replacement timing of the most worn grinding roller, which is inefficient.

  Furthermore, if gases having different temperatures are supplied from a plurality of gas supply ports at a plurality of locations, the influence on the mechanism at the position on the side where the high temperature gas is supplied, for example, a bearing of a grinding roller There is a high possibility that a decrease in the service life (the effect of the lubricating oil will decrease due to a high temperature) and a decrease in the service life of the oil seal, etc. will be problematic.

  By the way, in recent years, from the viewpoint of energy reduction, reduction of the amount of gas passing through the inside of the vertical crusher has been demanded, and as one of the methods for reducing the amount of gas supplied to the inside of the machine, From a discharge chute (sometimes called a stone chute) provided below the vertical crusher with a relatively large diameter, once extracted, using a mechanical conveying device such as a belt conveyor, A raw material refeeding system in which the material is again put into a vertical grinder and pulverized is generally widely used.

Since the raw material re-feeding system described above is a system that lifts the raw material from the lower side to the upper side using a conveying device arranged outside the machine, the raw material extracted from the discharge chute is again put into the machine. The gas flowing through the machine is not used in the processes up to this point.
Therefore, in the operation of the vertical crusher, the amount of gas supplied to the inside of the machine can be reduced, which has the effect of reducing energy.

  The discharge chute usually employs a highly airtight damper structure or the like in order to prevent air or the like from flowing into the machine when the raw material is extracted outside the machine. However, there is a limit to the airtightness, and the actual situation is that the sealing mechanism using a damper or the like cannot completely prevent the atmosphere or the like from flowing into the machine as a leak gas.

Therefore, when the discharge chute is provided adjacent to (including in the vicinity of) the gas supply port described above, the hot gas supplied into the apparatus from the gas supply port adjacent to the discharge chute is the leak gas described above. May cause a temperature drop.
And in the extreme case, the temperature of the hot gas is different between the gas supplied into the machine from the gas supply port adjacent to the discharge chute and the gas supplied into the machine from the gas supply port not adjacent to the discharge chute. In some cases, a temperature difference of about 100 ° C. occurred.
As a result, the gas having different temperatures is supplied from the gas supply port, thereby causing a problem when the gases having different temperatures are supplied from the plurality of gas supply ports.

  The present invention has been made in view of the problems as described above, and relates to a vertical crusher suitable for efficiently crushing raw materials with a uniform atmosphere in the machine and a method for operating the vertical crusher. .

In order to achieve the above object, a vertical crusher according to the present invention comprises:
(1) A rotatable crushing roller is provided on the upper surface of the rotary table, the raw material supplied on the rotary table is crushed between the rotary table and the crushing roller, and blown up by the gas supplied into the machine from below the rotary table. A vertical pulverizer that takes out from above the vertical pulverizer, a gas supply port that supplies hot gas as the gas, and an adjustment gas supply port that supplies adjustment gas for adjusting the temperature of the hot gas Prepare.

(2) The vertical crusher according to (1), wherein the gas supply port is provided at a plurality of locations, and at least one of the gas supply ports is provided with a damper for controlling the supply amount of the adjustment gas A gas supply port is provided, and a temperature measuring device is disposed above the gas supply port provided with the adjustment gas supply port, so that the temperature of the gas supplied from the gas supply port provided with the adjustment gas supply port is a desired value. The supply amount of the adjustment gas is adjusted by controlling the opening degree of the damper so as to reach the temperature.

(3) In the vertical crusher according to (2), an abrasion prevention plate is provided adjacent to the upper side of the temperature measuring device to cover the temperature measuring device from above.

In order to achieve the above object, the operation method of the vertical crusher according to the present invention is as follows:
(4) A rotatable crushing roller is provided on the upper surface of the rotary table, the raw material supplied on the rotary table is crushed between the rotary table and the crushing roller, and blown up by the gas supplied into the machine from below the rotary table. Is a method for operating a vertical crusher to be taken out from above the vertical crusher, comprising a plurality of gas supply ports for supplying hot gas into the machine, and adjusting at least one of the gas supply ports A first gas supply port provided with a gas supply port, and at least one of the gas supply ports as a second gas supply port adjacent to a discharge chute, the first and second gas supply ports And a temperature control device for controlling the supply amount of the adjustment gas at the adjustment gas supply port, and the temperature of the gas supplied from the second gas supply port, The first gas supply The supply amount of the adjustment gas is controlled so that the temperature of the gas supplied from the supply port becomes the same.

  According to the present invention, gas at different temperatures is prevented from being supplied from a plurality of gas supply ports, and the raw material is efficiently pulverized by making the atmosphere in the machine uniform.

It is a figure explaining the whole structure of a vertical crusher in connection with embodiment of this invention. It is a figure explaining arrangement | positioning of the gas supply port and adjustment gas supply port which concern on embodiment of this invention. It is a figure explaining the structure of the temperature measuring device according to the embodiment of the present invention. It is a conceptual diagram explaining the behavior of hot gas, leak gas, and adjustment gas according to the embodiment of the present invention. It is a conceptual diagram explaining the behavior of the stone removal according to the embodiment of the present invention. It is a reference figure explaining the example of arrangement | positioning of the number of the crushing rollers in connection with this embodiment, and a gas supply port. It is a reference figure explaining the operation mechanism of the grinding roller according to the present embodiment. It is a conceptual diagram explaining the behavior of hot gas and leak gas according to the prior art.

Hereinafter, an example of a preferred embodiment according to the present invention will be described with reference to the drawings.
FIGS. 1 to 7 show a preferred example of the embodiment of the present invention. FIG. 1 is a conceptual diagram for explaining the overall configuration of a vertical crusher, and FIG. 2 is a gas supply port. FIG. 3 is a diagram for explaining the arrangement of the adjustment gas supply port, and FIG. 3 is a diagram for explaining the configuration of the temperature measuring device. FIG. 4 is a conceptual diagram illustrating the behavior of hot gas, leak gas, and adjustment gas, and FIG. 5 is a conceptual diagram illustrating the behavior of stone removal. FIG. 6 is a reference diagram for explaining an example of the number of crushing rollers and arrangement of gas supply ports, and FIG. 7 is a reference diagram for explaining an operation mechanism of the crushing rollers. FIG. 8 is a conceptual diagram for explaining the behavior of the hot gas and the leak gas according to the prior art of the present invention.

Hereinafter, the preferable structure of the vertical crusher 1 which concerns on this embodiment is demonstrated.
As shown in FIG. 1 or FIG. 7, the vertical crusher 1 used in the present embodiment is installed in an upper casing 1B, a lower casing 1A, and a lower portion of the vertical crusher 1 that form the outline of the vertical crusher 1. The rotary table 2 driven by the reduced speed reducer 2B and the drive motor 2M, and the conical crushing roller 3 that rotates following the rotary table 2 are provided.
Further, the vertical crusher 1 shown in FIG. 1 includes an inverter power source (not shown) as a driving power source for the driving motor 2M, and is a variable speed type capable of arbitrarily changing the rotational speed of the rotary table 2 during operation. A vertical crusher 1.

Next, the internal structure of the vertical crusher 1 will be described.
The vertical crusher 1 shown in FIG. 1 includes an inner cone 19 having a substantially inverted truncated cone shape above the rotary table 2, and a fixed primary classifying blade 14 on the upper portion of the inner cone 19, A rotary classifier 15 having a rotary classifying blade is provided inside the primary classifying blade 14 above the cone 19. The rotary blades provided in the rotary classifier 15 are configured to rotate freely by being driven by a drive motor (not shown) installed on the top of the vertical crusher 1.

  Further, the vertical crusher 1 shown in FIG. 1 has a first gas supply port 33A (also referred to as a first gas supply port 33A) as a gas supply port for introducing gas below the rotary table 2. And a second gas supply port 33B (sometimes referred to as the second gas supply port 33B), in order to take out part of the raw material that has not been pulverized until the desired particle size is obtained as pulverized stones. A discharge chute 34 (sometimes referred to as a stone discharge chute 34) is provided, and an upper outlet 39 is provided above the rotary table so that the raw material (product) after pulverization can be taken out together with the gas. In addition, the raw material taken out from the discharge chute 34 is conveyed via the belt conveyor 61 etc., and it is the structure again injected into the inside of the machine from the raw material inlet 13 of the vertical crusher 1.

The details of the first gas supply port 33A and the second gas supply port 33B for supplying hot gas into the machine and the adjustment gas supply port 50 for supplying adjustment gas for adjusting the temperature of the hot gas will be described below.
Here, in the present embodiment, as shown in FIG. 6B, the two gas supply ports face each other, and the first gas supply port 33A provided with the adjustment gas supply port 50, and the discharge chute. As shown in FIG. 2, the second gas supply port 33 </ b> B adjacent to the lower side 34 is arranged so as to face the center of the axis of the turntable 2.

  In the present embodiment, the gas supply port arrangement or arrangement as shown in FIG. 6 (2) will be described as a preferred example, but the scope of application of the present invention is not limited to this. For example, for the other arrangements and arrangements shown in FIGS. 6 (1), (3), and (4), the gas supply port adjacent to the discharge chute 34 is the second gas supply port 33B, and other gas supply ports. May be used as the first gas supply port, and the arrangement or arrangement of the gas supply ports is not particularly limited as long as they do not depart from the technical idea of the present invention.

  In the present embodiment, the adjustment gas supply port 50 provided in the first gas supply port 33A includes an adjustment gas damper 50A that can be opened and closed inside, and the adjustment gas damper 50A is supplied from a control device (not shown). The supply amount of gas supplied from the adjustment gas supply port 50 into the machine can be adjusted by changing the opening degree according to the command signal.

  Although details will be described later, in the present embodiment, a so-called negative pressure type vertical crusher 1 is used, and the gas in the vertical crusher 1 is sucked by a suction fan connected to the upper outlet 39. Thus, the configuration is such that hot gas (hot air in the present embodiment) and adjustment gas (air at normal temperature in the present embodiment) are sucked and introduced into the apparatus from the gas supply port. In this embodiment, by adjusting the opening of the adjustment gas damper 50A by a command signal from the above-described control device (not shown), a desired amount of air is sucked into the machine and introduced, so that Air can be supplied into the machine as a conditioning gas.

  In the present embodiment, as shown in FIG. 2, the first temperature measuring device 51A (also referred to as the first temperature measuring device 51A) and the second gas supply are provided above the first gas supply port 33A. A second temperature measuring device 51B (sometimes referred to as a second temperature measuring device 51B) is disposed above the port 33B, and the first temperature measuring device 51A and the second temperature measuring device 51B are respectively shown in FIG. As shown in FIG. 3, a first wear preventing plate 53A or a second wear preventing plate 53B is provided.

In the present embodiment, a thermocouple type temperature sensor is used as the temperature measuring device, and as shown in FIG. 3, a steel material having an L-shaped cross section is disposed above the temperature measuring device 51A or 51B to measure the temperature. The wear preventing plate 53A or the wear preventing plate 53B for protecting the temperature measuring device 51A or 51B was configured by covering the device 51A or 51B so as to cover from above.
However, the configuration of the wear preventing plate according to the present invention is not limited to this, and for example, a U-shaped member or a semi-circular member may be used. Any structure can be used as long as it can protect the measuring part of the measuring device 51A or 51B, and the temperature rising from the gas rising from below flows into the measuring part, and is not particularly deviated from the technical idea of the present invention. It is not limited.

  In the present embodiment, with the configuration described above, by introducing hot gas (hot air in the present embodiment) from the first and second gas supply ports 33A and 33B during operation, To the primary classifying blade 14 and the rotary classifier 15 to generate a hot gas flow that flows to the upper outlet 39.

Hereinafter, the operation mechanism of the grinding roller 3 will be briefly described.
Four crushing rollers 3 of the vertical crusher 1 used in the present embodiment are arranged on the upper surface of the rotary table 2 as shown in FIG. When the turntable 2 is rotated, the turntable 2 is driven to rotate via the raw material.

Further, as shown in FIG. 7, the crushing roller 3 used in the present embodiment is attached to a swing lever and is pivotally supported around a shaft attached to the lower casing 1A. A hydraulic cylinder is attached to the arm. A hydraulic unit is connected to the hydraulic cylinder via a hydraulic line (not shown).
In the present embodiment, the hydraulic pressure of the hydraulic oil is increased by operating the hydraulic unit, the hydraulic cylinder is operated and the arm is driven, and the swing lever is moved so that the grinding roller 3 is desired. It has a configuration that can be pressed against the rotary table 2 side by applying pressure.

Next, the flow of the raw material in the vertical crusher 1 will be briefly described.
The raw material charged from the raw material inlet 13 and pulverized on the turntable 2 is blown up by the flow of hot gas, rises in the casing, and flows in the direction of the primary classification blade 14. It falls without reaching the primary classification blade 14 and is crushed again on the rotary table 2.
In addition, the raw material that has reached the primary classifying blade 14 and failed to pass through the rotary classifier 15 falls on the internal cone 19 and is supplied to the vicinity of the central portion of the rotary table 2. It is crushed. The raw material having a small diameter that has passed through the rotary classifier 15 is taken out from the upper outlet 39 as a product.

Here, in this embodiment, in the pulverized raw material, a part of the raw material having a relatively large diameter falls from the annular passage 30 and is located in the lower part of the vertical pulverizer 1 as waste stone. It is configured to be discharged from the discharge chute 34 to the outside of the machine.
In this embodiment, as shown in FIG. 1, a discharge chute damper 63 is arranged on the downstream side of the discharge chute 34 so that the atmosphere (air at normal temperature) is leaked from the outside of the machine to the inside of the machine at the time of stone removal. Although it is set as the structure which suppresses entering, leak gas has not been eliminated completely.

Hereinafter, a preferable example of the operation method of the vertical crusher 1 according to the present embodiment will be described.
At the start of operation of the vertical crusher 1, the first gas supply port 33 </ b> A and the second gas supply port are obtained by operating a suction fan (not shown) connected to the upper outlet 39 to make the inside of the machine have a negative pressure. Each hot gas is smoothly introduced from 33B.
In the present embodiment, one hot gas line is divided into two on the way and connected to the first gas supply port 33A and the second gas supply port 33B. The introduced hot gas forms a gas flow through the machine from below to above.

Next, the raw material is supplied to the vertical crusher 1, and the raw material (cement clinker which is an object to be pulverized in this embodiment) supplied to the raw material inlet 13 of the vertical crusher 1 is the center of the rotary table 2. It is thrown into the vicinity and moves to the outer peripheral side of the turntable 2 while drawing a spiral trajectory.
Then, the raw material moved to the outer peripheral side of the rotary table 2 is caught by the rotary table 2 and the crushing roller 3 and pulverized.
The raw material bitten by the rotary table 2 and the pulverizing roller 3 gets over the dam ring provided around the outer edge of the rotary table 2 and is a ring between the outer peripheral portion of the upper surface 2 of the rotary table and the casing. It goes to the passage 30 (sometimes referred to as the annular space 30).

The raw material that has reached the annular passage 30 is blown up by the above-described flow of the hot gas, rises in the casing, and flows in the direction of the primary classification blade 14, but the raw material having a large diameter and a large weight cannot reach the primary classification blade 14. And is crushed again on the rotary table 2.
In addition, the raw material that has reached the primary classifying blade 14 and failed to pass through the rotary classifier 15 falls on the internal cone 19 and is supplied to the vicinity of the central portion of the rotary table 2. It is crushed. The raw material having a small diameter that has passed through the rotary classifier 15 is taken out from the upper outlet 39 as a product.

  As shown in FIG. 5, some of the raw materials that are directed to the annular passage 30 are relatively heavy and fall below the rotary table 2, and the discharge chute damper 63 is moved from the discharge chute 34. Through the machine.

Here, in the present embodiment, during the operation of the vertical crusher 1, when discharging the waste stone from the discharge chute 34 to the outside of the machine, a large amount of air does not enter the inside of the machine via the discharge chute damper 63. To discharge.
However, there is a limit to the sealing performance of the discharge chute damper 63, and it is inevitable that gas outside the machine flows into the machine as leak gas while the stone is being discharged.
For this reason, even if one hot gas line is branched to supply the same temperature gas to the first gas supply port 33A and the second gas supply port 33B, the temperature of the hot gas actually supplied into the machine is different. There is a possibility that.

  Therefore, in this embodiment, when the vertical crusher 1 is operated, the temperature of the hot gas supplied from the first gas supply port 33A and the second gas supply port 33B is arranged above the first. The temperature is measured by the temperature measuring device 51A or the second temperature measuring device 51B and transmitted to a control device (not shown).

Then, when the temperature measured by the second temperature measuring device 51B (the hot gas temperature at the second gas supply port 33B) is lowered due to the influence of the normal temperature leak gas flowing from the discharge chute 34, a command signal is sent from a control device (not shown). To open the adjustment gas damper 50A provided at the first gas supply port 33A. As a result, as shown in FIG. 4, the hot gas supplied from the first gas supply port 31A by introducing the atmosphere (normal temperature air) from the adjustment gas supply port 50 to the first gas supply port 31A and supplying it. , The temperature of the hot gas supplied from the second gas supply port 33B is brought close to, and preferably the same.
When considering from the viewpoint of protecting the bearing, the above temperature difference is preferably within 30 ° C., and more preferably the same (temperature difference within 10 ° C.).

  If the example of a prior art is demonstrated with reference to FIG. 8, as mentioned above, the hot gas supplied in the apparatus from the gas supply port 133B adjacent to the discharge chute 134 will be remarkable by mixing with the leak gas of normal temperature. As a result, the temperature is lowered, and as a result, the state of the raw material biting by the crushing rollers becomes different in each crushing roller, and stable crushing becomes difficult.

  If the original temperature of the hot gas line supplied from the heat source is increased in order to compensate for the temperature of the hot gas sent from the second gas supply port 133B, the first gas supply port 133A that branches and flows from the same line. The temperature of the hot gas supplied from the heat source becomes higher than necessary, causing problems such as a reduction in the life of the bearings of the crushing roller 3.

On the other hand, in the present embodiment, the temperature of the hot gas supplied from the first gas supply port 31A is lowered to be the same as the temperature of the hot gas supplied from the second gas supply port 33B. The problem can be suppressed.
Further, in the operation method of the present embodiment, even if the original temperature of the hot gas line supplied from the heat source is compensated to compensate for the decrease in the hot gas temperature of the second gas supply port 33B due to the flow of leak gas, Since the hot gas temperature of the first gas supply port 33A can be freely adjusted, the above-described problems can be suppressed.

In the present embodiment, as an example of a preferable apparatus configuration, the first gas supply port 33A provided with the adjustment gas supply port 50 and the second gas supply port 33B adjacent to the discharge chute 34 below are provided. The vertical crusher 1 provided is described.
However, the form of the apparatus of the present invention is not limited to this. For example, when hot gases having different gas temperatures are originally supplied to a plurality of gas supply ports due to differences in the length of a piping line or a heat source, for example. Etc. are also applicable.
In addition, the gas supplied from the adjustment gas supply port 50 can use not only the atmosphere but also an inert gas or the like. Therefore, changes can be made without departing from the scope of the technical idea of the present invention.

  As described above, the vertical pulverizer and the operation method of the vertical pulverizer according to the present invention can be particularly preferably used when the atmosphere in the apparatus is made uniform and the raw material is efficiently pulverized.

DESCRIPTION OF SYMBOLS 1 Vertical crusher 2 Rotary table 3 Grinding roller 13 Raw material inlet 14 Primary classification blade 15 Rotary classifier 19 Internal cone 33A 1st gas supply port 33B 2nd gas supply port 34 Discharge chute 39 Upper outlet 50 Adjustment Gas supply port 50A Damper for adjusting gas 51A First temperature measuring device 51B Second temperature measuring device 53A First wear prevention plate 53B Second wear prevention plate

Claims (4)

A rotary crushing roller is provided on the upper surface of the rotary table, the raw material supplied on the rotary table is crushed between the rotary table and the crushing roller, and blown up by the gas supplied into the machine from below the rotary table. A vertical crusher taken out from above the crusher,
A vertical crusher provided with a gas supply port for supplying a hot gas as the gas and an adjustment gas supply port for supplying an adjustment gas for adjusting the temperature of the hot gas. Provided with a plurality of gas supply ports, provided at least one of the gas supply ports with an adjustment gas supply port provided with a damper for controlling the supply amount of the adjustment gas,
A temperature measuring device is disposed above the gas supply port provided with the adjustment gas supply port, and the damper is configured so that the temperature of the gas supplied from the gas supply port provided with the adjustment gas supply port becomes a desired temperature. The vertical pulverizer according to claim 1, wherein the supply amount of the adjustment gas is adjusted by controlling the opening degree.   The vertical crusher according to claim 2, wherein a wear prevention plate is provided adjacent to the upper side of the temperature measuring device to cover the temperature measuring device from above. A rotary crushing roller is provided on the upper surface of the rotary table, the raw material supplied on the rotary table is crushed between the rotary table and the crushing roller, and blown up by the gas supplied into the machine from below the rotary table. A method for operating a vertical crusher to be taken out from above the crusher,
A plurality of gas supply ports for supplying hot gas into the machine are provided, and at least one of the gas supply ports is a first gas supply port provided with an adjustment gas supply port. At least one of them as a second gas supply port adjacent to the discharge chute,
A temperature measuring device is disposed above each of the first and second gas supply ports, and a flow rate control mechanism for controlling the supply amount of the adjustment gas is disposed at the adjustment gas supply port.
Operation of a vertical crusher that controls the supply amount of the adjustment gas so that the temperature of the gas supplied from the second gas supply port is the same as the temperature of the gas supplied from the first gas supply port Method.

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