JP2000079375A - Apparatus and method for automatic power classification - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject apparatus and method enabling stable classification even if the particle size distribution of a raw powder is varied. SOLUTION: Blaine powder finness automatic measuring devices 1a, 1c sampling a predetermined amt. of a sample to be capable of measuring the finness thereof by a Blaine method are arranged before and after a classifier 53. By controlling the number of rotations of the motor 54 of the classifier 53 on the basis of measured results by a control unit 56, the classifying point of the classifier 53 is adjusted. By this constitution, even if the particle size distribution of the raw powder supplied from a raw powder silo 50 is varied, the qualities of the coarse powder and fine powder respectively guided to a coarse powder silo 51 and a fine powder silo 52 can be kept constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a classification apparatus and method for separating raw powders containing powders having different particle diameters according to the particle diameter, and more particularly to an automatic powder classification suitable for classification of cement, fly ash and the like. Apparatus and method.

[0002]

2. Description of the Related Art Conventionally, for example, in the production of cement, fineness control of cement raw materials and products has been performed. In a thermal power plant, fly ash processing equipment for recycling fly ash generated in a coal-fired boiler as a cement raw material has been put to practical use. In this case, the collected fly ash is classified after being controlled for fineness, and is classified into a recycled one and a non-reused one. In any case, a Blaine air permeation apparatus to which the Blaine method is applied is conventionally used for fineness control of cement and fly ash.

[0003] This brane air permeation device mainly comprises
It consists of a manometer filled with manometer liquid and a transmission cell mounted on the top of the manometer. At the time of fineness measurement, the sample powder is introduced into the transmission cell and the plunger is manually inserted into the transmission cell, thereby compressing the sample powder in the transmission cell to form a bed (compressed body). . In this state, the transmission cell is mounted on the manometer, and the manometer liquid in the manometer is sucked up to the top marked line A. Thereafter, the cock is closed, and the passage time during which the descending head of the manometer liquid passes between the predetermined marked lines B and C is measured. The specific surface area of the sample powder can be determined from the measured transit time and the previously determined device constants and the like.

[0004]

However, when a conventional brane air permeation device is used, the operation of forming a bed requires extremely skill since the plunger must be manually operated. That is, since the pressure when the plunger is pushed into the permeation cell causes individual differences, a certain porosity (porosity)
This makes it difficult to form a bed having a measurement result, which may lead to measurement errors. In addition, when sampling powder from various powder processing equipment at cement plants and thermal power plants and measuring the fineness using a conventional brane air permeation device, sampling of the powder, introduction into the cell, measurement, and compression are performed. ,
Since the operations such as the operation of the brane air permeation device were all performed manually, the labor and time required for measuring the fineness were enormous.

[0005] For this reason, when classifying cement or fly ash, the particle size to be separated is accurately determined unless the particle size distribution in the raw powder before classification is kept constant. It was difficult to control, and it was only possible to grasp the properties after classification.

Accordingly, an object of the present invention is to provide an automatic powder classification apparatus and method capable of performing stable classification even if the particle size distribution of the raw powder fluctuates.

[0007]

To solve the above problems, an automatic powder classifier according to the present invention is an automatic powder classifier that automatically separates raw powders containing powders having different particle sizes according to the particle size. In (1) a classifier that separates the input raw powder into a plurality of groups based on the size of the particle size, and (2) a classifier that is input to each group and the classifier after classification discharged from the classifier. A sampling device for sampling a predetermined amount of each sample from a predetermined group in the;
(3) a sample powder supply unit for introducing a predetermined amount of powder into the cell;
A brane air permeation unit for compressing the powder in the cell into which the powder is introduced at a predetermined pressure and then transmitting air to measure the fineness of the powder in the cell by the Blaine method; (4) an automatic Blaine fineness measuring device that is connected to a sampling device and that measures the fineness of a sampled sample, comprising: a cell transport mechanism that moves the cell between the supply unit and the brane air permeable unit;
A control device for controlling the operation state of the classifier so that the classification point in the classifier is maintained at a predetermined classification point based on the fineness of the sample measured by the Blaine fineness measuring device. It is characterized by.

On the other hand, according to the automatic powder classification method of the present invention, there is provided an automatic powder classification method for automatically separating raw powder in which powders having different particle sizes are mixed according to the particle size. A classification step of separating into a plurality of groups according to the size of the particle size, and (2) a predetermined amount of sample from each group after classification discharged from the classifier and a predetermined group in the raw powder to be fed into the classifier. A sampling step of sampling; (3) a sample powder supply unit for introducing a predetermined amount of powder into the cell; and compressing the powder in the cell into which the powder has been introduced at a predetermined pressure and allowing air to pass therethrough. A Blaine air permeation unit for measuring the fineness of the powder in the cell by the Blaine method,
The sample sampled in the sampling process is guided to an automatic Blaine fineness measuring apparatus having a cell transport mechanism for moving cells between the sample powder supply unit and the Blaine air permeation unit, and the automatic fineness measurement is performed. A measurement step of performing measurement, and (4) a control step of controlling the classification step based on the fineness of each sample measured in the measurement step to adjust the classification point to be maintained at a predetermined classification point, It is characterized by having.

In the present invention, an automatic Blaine fineness measuring apparatus used for controlling fineness comprises a sample powder supply section for introducing powder into a cell, and a Blaine for actually measuring fineness by the Blaine method. The air permeable unit is independent from the air permeable unit, and has a cell transport mechanism for moving cells between them. Therefore, it is possible to automatically measure the fineness of the sample online. Therefore, the fineness of each group before and after classification can be managed in real time. By controlling the classifier based on these measured fineness, it is easy to maintain the fineness of each group after classification at the desired fineness,
It can follow the fluctuation of the particle size distribution of the raw powder.

[0010]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In order to facilitate understanding of the description, the same constituent elements are denoted by the same reference numerals as much as possible in each drawing, and redundant description will be omitted.

FIG. 1 is an overall configuration diagram of an automatic powder classification system according to the present invention. This system is a classifier for fly ash, cement, etc., which separates coarse powder with a large particle size and fine powder with a small particle size according to the purpose of using the raw powder. is there.

As shown in FIG. 1, this system comprises a raw powder silo 50 for storing raw powder before classification, a coarse silo 51 for storing coarse powder having a large particle size after classification, and a small powder silo 51 for storing coarse powder after classification. And a fine powder silo 52 for storing fine powder. And
A classifier 53 is arranged between the raw powder silo 50 and the coarse powder silo 51 and the fine powder silo 52. Here, classifier 5
Reference numeral 3 denotes a rotary blade type classifier, which has a configuration capable of adjusting the classification point by controlling the number of rotations of a motor 54 for rotating the rotary blade.

Between the classifier 53 and the fine powder silo 52,
A fine powder collector 55 for separating the raw powder from the transport air is provided. In addition, the outlet of the raw powder silo 50, the inlet of the coarse powder silo 51, and the outlet of the fine powder collector 55 each have a Blaine fineness measuring apparatus 1a to 1 having a sampling device.
1c is attached. These automatic measuring devices 1a
1c are sent to the control device 56 for processing. The control device 56 is also connected to a blower 57 that supplies air for transportation, the motor 54 of the classifier 53, and various valves and the like in the classification system.

Here, an automatic Blaine fineness measuring apparatus used in the automatic powder classification system of the present invention will be described in detail. FIG. 2 is a schematic diagram showing the outline of the automatic Blaine fineness measuring apparatus. The automatic Blaine fineness measuring device 1 shown in FIG. 1 is useful for fineness control in a powder processing facility of a cement plant or a fly ash processing facility of a thermal power plant. It measures the degree. The automatic Blaine fineness measuring apparatus 1 has a powder collecting section 2 for collecting powder from various powder processing equipment, and the powder collecting section 2 includes a powder storage hopper and a powder storing hopper of the powder processing equipment. It can be connected to the body transfer pipe. The powder sampling unit 2 has a built-in powder sampling shaft 3, which is connected to an air cylinder 4. The tip of the powder sampling shaft 3 is formed in a hollow triangular pyramid shape having a predetermined volume (for example, 500 cc). The air cylinder 4 is connected to a compressor 5 controlled by the control PC 30.

When powder is sampled from the powder processing equipment, the compressor 5 is operated via the control PC 30 to send compressed air to the air cylinder 4, and the powder sampling shaft 3 is moved to the powder storage hopper or the powder storage hopper. Protrude into the transfer pipe. Then, by contracting the air cylinder 4 and pulling back the powder collecting shaft 3, a certain amount of powder is collected from the powder processing equipment. As a result, the sampling of the powder can be automatically performed, so that the work of measuring the fineness can be saved. Further, the powder sampling shaft 3 is operated only at the time of sampling, and remains in the powder sampling unit 2 except at the time of sampling. There is no hindrance. In addition, a screw feeder, a rotary feeder, or the like may be used as the powder collecting unit 2.

A foreign matter removing section 6 is provided below the powder collecting section 2, and a sample powder supply section 7 is provided below the foreign matter removing section 6. The powder sampled by the powder sampling shaft 3 falls from the powder sampling unit 2 and is received by the foreign matter removing unit 6, and after the mixed foreign matter is removed, is supplied to the sample powder supply unit 7. You. Further, the foreign matter mixed in the powder is sieved into the foreign matter processing tank 6a. As described above, by providing the foreign matter removing unit 6 between the powder collecting unit 2 and the sample powder supplying unit 7, the powder from which the foreign matter has been removed can be used as the sample powder. The measurement error of the degree is reduced. Foreign matter removal unit 6
A vibration type feeder or the like is used, and the operation of the foreign matter removing unit 6 is also controlled by the control PC 30.

The sample powder supply section 7 has a powder receiving hopper 7a at the upper portion thereof for receiving the powder supplied from the powder collecting section 2 via the foreign substance removing section 6. The powder receiving hopper 7a communicates with an upright powder storage section 7b via two valves. That is, the powder dropped from the foreign matter removing unit 6 is received by the powder receiving hopper 7a,
It is stored in the powder storing section 7b. The powder storage unit 7b has a capacity of, for example, about 2000 cc, and contains therein a mixing and stirring mechanism 8 including a motor driven stirring shaft and the like.
Is built-in. Thereby, the powder can be collected and stored in a plurality of times, mixed and stirred, and then used as a sample powder, so that a more accurate fineness measurement can be performed.

From the lower part of the powder storage section 7b, a powder supply mechanism 7c composed of a screw feeder or the like driven by a motor extends in the horizontal direction. This powder supply mechanism 7
A powder supply nozzle 7d extends vertically downward from the tip of c through a valve. Further, the sample powder supply unit 7
Is a cell cleaning unit 1 disposed below the powder supply nozzle 7d.
Has zero. On the upper surface of the cell cleaning section 10, a cell 11 for forming a bed by introducing powder at the time of fineness measurement can be placed. These mixing and stirring mechanisms 8,
The operation of the powder supply mechanism 7c and the cell cleaning unit 10 is controlled by the control P
Controlled by C30. On the other hand, surplus powder in the powder storage section 7b is stored in the tank 9.

Here, the cell 11 will be described. As shown in FIG. 3, the cell 11 has a substantially cylindrical shape and is used in a state in which about 80 cc of powder is contained therein. The cell 11 is formed of a hard metal such as stainless steel or the like.
4 is fitted. This filter 14 is formed of a sintered metal or a porous plate,
It has a mesh size of about μm. As a result, the powder introduced into the cell 11 does not accumulate on the filter 14 and spill out of the cell 11, and
The air permeation at the bottom of the is ensured. It is possible to use a general filter paper instead of the filter 14, but if such a filter 14 is used, it is not necessary to replace the filter paper every time the fineness is measured.

The lower end of the cell 11 is provided with a lower flange 11a formed in a circular flange shape. A concave portion is formed on the lower surface of the lower flange portion 11a, and the filter 14 is fitted into the concave portion. A support plate 12 having an outer diameter substantially equal to the outer diameter of the lower flange 11a is fixed to the lower surface of the lower flange 11a.
A perforated plate 13 having substantially the same diameter as the inner diameter of the filter 14 is fitted into the center of the upper surface of the support plate 12.
As a result, the filter 14 is supported by the support plate 12 via the effective plate 13 and is reliably held on the cell 11. In addition, by forming the bottom of the cell 11 in a flange shape, the cell 11 can be stably placed on the cell cleaning unit 10 or the like. Further, an upper flange portion 11b formed in a flange shape is provided at an upper portion of the cell 11, and a plurality of holes 11c are formed in the upper flange portion 11b.

When the powder is introduced into the cell 11 by the sample powder supply unit 7, the cell transport mechanism 15 moves the cell 11 up to the brain air transmission unit 20 arranged side by side with the sample powder supply unit 7. Conveyed. Cell transport mechanism 15
For example, as shown in FIG. 4, the base of the line connecting the cell cleaning unit 10 of the sample powder supply unit 7 and the cell mounting table 21 of the brane air permeable unit 20 is opposed to the base of an isosceles triangle. Are placed at the positions of the vertices. The cell transfer mechanism 15 holds the cell 11 between the cell cleaning unit 10 and the cell mounting table 21, and is rotatable in the horizontal direction and vertically movable in the vertical direction.
The drive unit 17 is controlled by C30 and controls the drive of the transport arm 16. At the tip of the transfer arm 16,
A cell holder 18 is provided. This cell holder 18
Has a U-shape, and a projection 18a is formed on the upper surface thereof to engage with a hole 11c formed in the upper flange portion 11b of the cell 11. The transfer arm 16 has a built-in load cell 18b.

Thus, if the powder supply mechanism 7c is operated with the cell 11 held by the cell holder 18 positioned below the powder supply nozzle 7d, the powder is supplied via the powder supply nozzle 7d. The powder is introduced into the cell 11, and the weight of the powder in the cell is measured by the load cell 18b. The value measured by the load cell 18b is sent to the control PC 30. When the cell 11 is transferred between the sample powder supply unit 7 and the brane air permeable unit 20, the cell cleaning unit 10
Alternatively, the transfer arm 16 is moved up and down and rotated with respect to the cell 11 placed on the cell
The cell 11 is positioned between the free ends of the book. Then, the cell holder 18 is raised with respect to the upper flange portion 11b of the cell 11, and the projection 18a is inserted into the hole 11c of the upper flange portion 11b. As a result, the cell 1 is
1 is held, and the cell 11 can be transferred by rotating the transfer arm 16 in this state. Cell 11
When the is mounted on the cell cleaning unit 10 or the cell mounting table 21, the transfer arm 16 is lowered with respect to the upper flange 11b.

As shown in FIG. 2, the Blaine air permeable unit 20 measures the fineness of the powder by the Blaine method using the cell 11 and the manometer 22. A plunger 23 extending in the vertical direction is disposed above a cell mounting table 21 on which the cells 11 transported to the brane air transmission unit 20 are mounted. Plunger 23
Is connected to an air cylinder 24 operated by the compressor 5. That is, the air cylinder 24
Is expanded and contracted, the plunger 23 moves up and down with respect to the cell 11 mounted on the cell mounting table 21. Thus, the bed can be formed by compressing the powder in the cell 11 at a predetermined pressure (for example, 7 kg / cm 2 G) via the plunger 23. Further, the amount of movement of the plunger 23 is detected by the micro gauge 25. The detected value of the micro gauge 25 is sent to the control PC 30 and the control PC 30
30 measures the bed height based on the indicated value of the micro gauge 25.

As shown in FIG. 2, the plunger 23 is connected to the manometer 22 via an air tube.
The manometer 22 is connected to a vacuum pump 26 that is filled with a predetermined manometer liquid and that is driven and controlled by the control PC 30. When measuring the fineness of the powder introduced into the cell 11, the control PC 30 operates the vacuum pump 26 and opens and closes a predetermined valve or cock. In addition, the brain air permeation unit 20
Is provided with a measuring unit 27 for measuring the passage time of the descending head of the manometer liquid passing between the predetermined marked lines B and C, and the measured value of the measuring unit 27 is sent to the control PC 30. Then, the control PC 30 controls the load cell 18b.
And brane air permeation unit 20 (micro gauge 2
5 and the fineness (specific surface area) of the powder are measured based on the measurement values of the measuring unit 27).

Further, the automatic Blaine fineness measuring apparatus 1 can be provided with an automatic true specific gravity meter 28 as shown in FIG. In this case, the automatic Blaine fineness measuring device 1
When the fineness of the powders having different true specific gravities is measured by using the automatic true specific gravity meter 28, the true specific gravity of the powders may be measured before the fineness measurement by the Blaine air transmission unit 20. Thus, the supply amount of the sample powder to the brane air transmission unit 20 can be corrected based on the measurement value of the automatic true specific gravity meter 28. Further, the automatic Blaine fineness measuring apparatus 1 may be provided with a component analyzer 29 such as an X-ray analyzer or an infrared analyzer. Thereby, the effective components (Si, Al, Fe, etc.) in fly ash
And analysis of impurity components (V, Se, etc.), analysis of unburned carbon,
Measurement of the amount of adsorbed methylene blue becomes possible. Further, the configuration may be such that the ambient temperature and the sample temperature are input to the control PC 30.

In addition, the automatic Blaine fineness measuring device 1 comprises:
It has an automatic dust collecting device 31. When the fineness measurement is completed, the compressed air is supplied to the powder sampling unit 2, the sample powder supply unit 7, the cell cleaning unit 10, the brane air permeable unit 20 and the like by the compressor 5, and the automatic dust collecting device 31 is used. Activate Thereby, the whole Blaine fineness measuring apparatus 1 can be washed. The control PC 30
Are based on a control program created in accordance with a processing step, a time schedule, and the like of a powder processing facility, based on a powder sampling unit 2, a compressor 5, a foreign substance removing unit 6, a sample powder supply unit 7, a cell transport mechanism 15, Air permeation unit 2
0, controls the operation of the automatic dust collecting device 31, various valves and the like.

Next, the operation of the automatic powder classification system according to the present invention, that is, the automatic powder classification method according to the present invention will be described in detail with reference to FIGS. Here, 1000 to 8000 branes of raw powder are 1000 to 3
An example will be described in which 500-brane coarse powder and 3500 to 8000-blane fine powder are separated.

The raw powder contained in the raw powder silo 50 is supplied from the blower 57 and is guided into the classifier 53 by the primary air flowing in the direction of arrow A in FIG. here,
The fineness of the raw powder guided to the classifier 53 is measured by sampling the raw powder in the silo by the automatic Blaine fineness measuring device 1 attached to the raw powder silo 50.

Here, the specific measurement procedure will be described with reference to FIGS. First, the cell 11 is held by the cell holder 18 of the transfer arm 16 and
It is placed on the cell cleaning unit 10 of the sample powder supply unit 7.
The control PC 30 operates the air cylinder 4 based on a predetermined control program to cause the powder sampling unit 2 to sample a certain amount (500 cc, for example) of powder from the raw powder silo 50. The cycle of powder collection is, for example, one hour per hour.
Times. The powder collected by the powder collecting unit 2 is
The powder is supplied to the powder storage section 7b of the sample powder supply section 7 via the foreign substance removing section 6.

Here, the cycle of fineness measurement is, for example, once every four hours. That is, the control PC 30 activates the mixing and stirring mechanism 8 when the powder collection unit 2 is operated four times and a predetermined amount (for example, 2000 cc) of powder is stored in the powder storage unit 7b. Thereby, the powder in the powder storage section 7b is mixed and stirred. Then, the powder supply mechanism 7c is operated, and the powder in the cell 11 is introduced via the powder supply nozzle 7d. The control PC 30 includes a load cell 18b.
Then, the weight of the powder in the cell 11 is measured, and the operation of the powder supply mechanism 7c is stopped when a predetermined amount (for example, about 80 cc) of the powder is introduced into the cell 11. Load cell 18
The measured value of b is stored in a predetermined storage area of the control PC 30. Next, the control PC 30 operates the cell transport mechanism 15. Thereby, the cell 11 is transferred from the sample powder supply unit 7 to the cell mounting table 21 of the brane air permeable unit 20.

The cell 11 mounted on the cell mounting table 21
It is located below the plunger 23. In this state, the air cylinder 24 is operated, and the plunger 23 is lowered with respect to the cell. The control PC 30 extends the air cylinder 24 until the indicated value of the micro gauge 25 reaches a predetermined value. Thus, the powder in the cell 11 is compressed at a predetermined pressure to form a bed. As described above, in the automatic Blaine fineness measuring apparatus 1, the operation of the plunger requiring extremely skill is automated, so that the work of measuring the fineness can be greatly reduced. In addition, there is no need to manually perform the plunger operation, and reproducibility of the plunger operation is ensured, so that a certain porosity (porosity) is maintained.
Can be formed very easily. Therefore, the fineness of the powder can be measured easily and with high accuracy.

When the bed forming operation in the cell 11 has been completed, the brane air permeable unit is operated to perform a predetermined measurement. That is, the vacuum pump 26 is operated, and the manometer liquid in the manometer is sucked up to the top marked line A. Thereafter, the predetermined cock is closed, and the measuring unit 27 measures the passing time during which the descending head of the manometer liquid passes between the predetermined marked lines B and C. The control PC 30 receives the measurement value of the measurement unit 27, measures the fineness (specific surface area) of the powder based on the measurement values of the load cell 18b, the micro gauge 25, and the measurement unit 27, and transmits the measurement result to the control device 56 ( (See FIG. 1). After the measurement is completed, the cell 11 is transferred onto the cell cleaning unit 10 by the cell transfer mechanism 15. The control PC 30
A predetermined valve is opened and the compressor 5, the cell cleaning unit 10, and the automatic dust collecting device 31 are operated. After the compressed air is first introduced into the cell 11 from below,
From above, compressed air is introduced. Such a cell 11
The introduction of compressed air into the interior is repeated as needed. Thereby, the bed in the cell 11 is discharged, and the inside of the cell 11 is cleaned.

The operating conditions of the classifier 53 are calculated and set from the actual data based on the Blaine value of the raw powder thus measured and the target value of the classification. Specifically, the number of revolutions of the motor 54 of the classifier 53 and the amount of primary air and secondary air to the classifier 53 by adjusting each valve are adjusted, and the classification point of the classifier 53 is set to a predetermined Blaine value ( For example, 3500
(Brain).

As described above, the raw powder is fed into the classifier 53 together with the primary air from the direction of arrow A, that is, from below.
Secondary air is being introduced. Inside the classifier 53, the coarse powder having a large particle diameter falls by the operation of the rotary blade, is discharged in the direction of arrow C from a discharge port provided on the lower side, and is guided to the coarse powder silo 51. On the other hand, the fine powder having a small particle diameter is conveyed together with the primary air and the secondary air, and is discharged in the direction of arrow D from the discharge port at the top of the classifier 53. The discharged fine powder is
It is separated from primary air and secondary air inside the fine powder collector 55 and stored in the fine powder silo 52. The separated air is
It is led to the blower 57.

The Blaine values of the coarse powder and the fine powder to be sent to the coarse powder silo 51 and the fine powder silo 52 are measured by the Blaine fineness automatic measuring devices 1b and 1c, respectively. Sent to. When the Blaine values of the coarse powder and the fine powder deviate from the target values, the control device 56 performs the feedback control so that the boundary of each of the Blaine values matches the target value of 3500 Brain. Control.

As a result, even if the particle size distribution of the raw powder, that is, the Blaine value, which has conventionally been difficult to handle, fluctuates,
Since the Blaine value of each of the coarse powder and the fine powder can be maintained at the target value, stable classification operation can be performed, which contributes to labor saving.

Here, the embodiment in which the automatic Blaine fineness measuring apparatus is individually provided at each measuring point has been described.
Only a sampling device may be provided at each measurement point, and a sample sampled at each measurement point may be transported and guided to one or a predetermined number of automatic Blaine fineness measuring devices to measure the Blaine value.

FIG. 5 is a schematic diagram showing a second embodiment of the present invention. This is a schematic diagram showing the fly ash processing equipment using the classification device 53 according to the present invention. The fly ash processing equipment shown in the figure is for collecting fly ash generated in a coal-fired boiler 101 of a thermal power plant and reusing it as a cement raw material. Fly ash is economizer 102, air preheater 103,
The ash is collected from hoppers provided below the electric dust collector 104 and stored in the ash relay tank 106 via the ash transfer pipe 105. Fly ash stored in the ash relay tank 106 is classified into non-recovered ash and recovered ash based on its fineness. Then, by operating the pressure-feed blower 57, the non-recovered ash is removed from the non-collected ash storage silo 63.
The collected ash is transferred to the collected ash storage silo 62.

Here, in this fly ash processing equipment, the above-mentioned automatic Blaine fineness measuring apparatus 1d is connected to a position upstream of the ash relay tank 106 of the ash transfer pipe 105. That is, fly ash is classified based on the fineness measured by the Blaine fineness measuring apparatus 1d. As described above, by sampling fly ash before storing it in the ash relay tank 106, the fineness of fly ash that has not been contaminated can be measured, so that fly ash can be classified with high accuracy. It should be noted that an automatic Blaine fineness measuring device is connected to the hopper provided below the electric dust collector 104 and the ash relay tank 106, and fly ash is collected and fineness is measured. The fly ash may be classified by performing a comparison operation by 56.

The fly ash stored in the non-recovered ash storage silo 63 is loaded on a vehicle or a ship according to a predetermined schedule. On the other hand, the fly ash stored in the recovered ash storage silo 62 is further classified into recovered powder, fine powder and fine powder. That is, only the recovered powder is directly loaded from the recovered ash storage silo 62, the fine powder is stored in the fine powder storage silo 60, and the fine powder is stored in the fine powder storage silo 61. In this case, classification of fly ash is performed by a rotary blade type classification device 53 provided above the fine powder storage silo 60.

Here, in this fly ash processing equipment, an automatic Blaine fineness measuring device 1e is connected to an ash transfer pipe 63 connecting the classifying device 53 and the fine powder storage silo 61. Thereby, fine powder and fine powder can be classified with high accuracy. The control device 56 controls the number of revolutions of the rotating blades in the classifying device 53 based on the measurement result of the automatic Blaine fineness measuring device 1e in the same manner as in the first embodiment, so that a desired Blaine value is obtained. Classification of fine powder and fine powder can be completely automated.

[0042]

As described above, according to the present invention, the fineness before and after the classification is measured by the automatic Blaine fineness measuring device, and the classification point is controlled so as to maintain the classification point within a predetermined range based on the measured fineness. Therefore, even when the fineness of the raw powder fluctuates, the operating conditions of the classifier can be changed to follow the fluctuation, and stable classification can always be performed.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an automatic powder classification system according to the present invention.

FIG. 2 is a schematic diagram showing an outline of an apparatus for automatically measuring Blaine fineness in the system of FIG. 1;

FIG. 3 is a sectional view showing a cell included in the automatic measuring device of FIG.

FIG. 4 is a perspective view showing a cell transport mechanism included in the automatic measuring device of FIG. 2;

FIG. 5 is a schematic view showing another embodiment of the automatic powder classification system according to the present invention.

[Explanation of symbols]

1 ... Blaine fineness automatic measuring device, 2 ... Powder sampling unit, 6
... Foreign matter removing section, 7... Sample powder supply section, 7 c. Powder supply mechanism, 8... Mixing and stirring mechanism, 11 .cell, 15 .cell transport mechanism, 20... Brane air transmission unit, 22. , 30 ... Control PC, 53 ... Classifier, 56 ... Control device.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoichi Kato 1-1-1, Yatocho, Tanashi-shi, Tokyo Sumitomo Heavy Industries, Ltd. Tanashi Works (72) Inventor Kunio Iwamoto 5-27 Sendagaya, Shibuya-ku, Tokyo No. 7 Inside a Seishin Company (72) Inventor Kenzo Ogushi 5-27-7 Sendagaya Shibuya-ku, Tokyo Inside a Seishin Company

Claims (2)

[Claims] 1. An automatic powder classification apparatus for automatically separating raw powders containing powders having different particle diameters according to the particle diameter, wherein the input raw powders are separated into a plurality of groups according to the size of the particle diameter. A sampling device for sampling a predetermined amount of a sample from each group after classification discharged from the classifier and a predetermined group in the raw powder to be input to the classifier; A sample powder supply unit to be introduced, and the air in the cell into which the powder has been introduced is compressed at a predetermined pressure, and the air is transmitted therethrough to measure the fineness of the powder in the cell by the Blaine method. A permeation unit, and a cell transport mechanism for moving cells between the sample powder supply unit and the brane air permeation unit, and connected to the sampling device to measure fineness of a sample sampled. The automatic Blaine fineness measuring device for performing the determination, based on the fineness of the sample measured by the automatic Blaine fineness measuring device, based on the classification point of the classifier so that the classification point in the classifier is maintained at a predetermined classification point An automatic powder classification device, comprising: a control device for controlling an operation state. 2. An automatic powder classification method for automatically separating raw powders containing powders having different particle diameters according to the particle diameter, wherein the input raw powders are separated into a plurality of groups according to the size of the particle diameter. A sampling step of sampling a predetermined amount of a sample from each group after classification discharged from the classifier and a predetermined group in the raw powder to be input to the classifier; A sample powder supply unit to be introduced, and the air in the cell into which the powder has been introduced is compressed at a predetermined pressure, and the air is transmitted therethrough to measure the fineness of the powder in the cell by the Blaine method. In the automatic Blaine fineness measuring apparatus, which comprises a transmission unit and a cell transport mechanism for moving cells between the sample powder supply unit and the Blaine air transmission unit, the sample is sampled in the sampling step. A measuring step of automatically measuring the fineness of the sample by guiding the sample, based on the fineness of each sample measured in the measuring step, the classification step is controlled to control the classification step to a predetermined classification point. And a control step of adjusting so as to be maintained. An automatic powder classification method, comprising: