JP5345907B2 - Powder processing equipment and powder processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide powder treatment equipment for treating a powder to a target particle size which produces a crushed product of high sphericity efficiently. <P>SOLUTION: The powder treatment equipment includes two powder tanks 11a and 11b consisting of a powder supply tank and a powder storage tank, a crusher 31 crushing a raw powder to smooth the surface of the particles, a powder feeder 21a feeding the raw powder from the powder supply tank 11a to the crusher 31, a collector 41 receiving and collecting the powder crushed by the crusher 31 and a powder storage tank 11b storing the collected powder and is configured in such a way that the powder stored in the powder storage tank 11b can be fed to the crusher 31 through a powder feeder 21b. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a powder processing facility and method for pulverizing powder particles to obtain a product powder having a desired particle size and high sphericity.

  In recent years, electronic technology materials, optical technology materials, polymer materials, resins used as medical materials, fine powders such as carbon, metals, minerals, especially toners and pharmaceuticals, etc., with an average particle size of several 100 μm or less, In particular, in fine powders having an average particle size of several μm to several tens of μm, there has been a growing demand for improving fluidity, filling properties, etc. by improving the powder shape, particularly by making the irregular particle shape spherical.

  Patent Document 1 discloses a powder processing apparatus that can be used for spheroidizing a fine powder. The disclosed powder processing apparatus includes a cylindrical rotor that rotates at a high speed and a cylindrical stator that is disposed with a small gap of, for example, 0.5 to 5 mm on the outside thereof, and a raw material that is placed in an airflow. Supply from one end of the gap between the rotor and the stator, and discharge the spherical product powder from the other end of the gap. The rotor and the stator are formed with grooves and / or spiral grooves that are continuous in the axial direction and the circumferential direction. For example, by rotating the rotor at a high speed such as a normal peripheral speed of 100 to 130 m / s and a maximum peripheral speed of 170 m / s, a large number of micro vortices are formed in the gap between the rotor and the stator. The dispersed irregular particle size powders are brought into strong contact with each other.

By using the disclosed powder processing apparatus, irregularities on the particle surface of a fine powder having a particle diameter of several hundreds μm or less and several μm to several tens μm can be smoothed and made spherical. However, even if the number of rotations is increased, the particles do not become finer.
Thus, in the powder processing apparatus described in Patent Document 1, since the particle diameter is not reduced, the pulverization is not performed as much as possible and the unevenness on the particle surface is processed so that the powder shape after the powder processing is Does not change the particle shape before treatment.

  On the other hand, there is a crusher composed of a rotor that has a special groove shape and rotates at a high speed, a stator that has a special groove shape in the powder contact portion like the rotor, and an inlet and outlet casing. In this pulverizer, particles are violently collided by numerous vortexes generated between a rotor and a stator having a special groove shape and contact is repeated, whereby pulverization proceeds and a powder having an excellent particle size distribution is produced.

  A normal powder processing facility for adjusting the particle size of the raw material powder includes, for example, the pulverizer, a powder supply tank, a powder supply machine, a collection device, and a blower. The Air is sucked in by the blower, and a conveying airflow is formed through the raw material supply pipe, the pulverizer, and the collection device from the intake port. The raw material powder stored in the powder supply tank is added to the conveying airflow in a fixed amount by the powder supply machine and supplied to the raw material supply port of the pulverizer.

  The raw material powder is subjected to the powder processing of the pulverizer while passing through the pulverizer, is transported to the discharge port, and is further supplied to the collection device by a conveying airflow. The treated powder separated from the airflow by the collecting device is collected at the bottom of the collecting device and is carried out from an outlet provided at the bottom.

  Such a powder processing facility can be called an open circuit system because it obtains the product powder by only one pass through the pulverizer. When using the open circuit method, the product powder needs to be passed through the pulverizer only once, so the rotator speed in the pulverizer is increased, so that the processing conditions are strict and the residence time is sufficient. The powder has to be processed significantly.

  For this reason, the particle size of the powder has a large distribution, and the sphericity does not increase. Further, when the product powder is sorted by a classifier in order to have a preferable particle size distribution, a waste powder is wasted. Further, if the rotational speed of the rotor is increased in order to perform large processing on the powder, the unloaded power increases and the power that can be used for pulverization decreases, so it is necessary to reduce the amount of powder processing.

  In addition, using a classifier, the powder processed by the pulverizer is sorted by the classifier, the particles having a particle size of a predetermined size or more are returned to the pulverizer, and repeatedly subjected to powder processing and a sorting process. There is a closed circuit system in which particles are sent from a classifier to a collection device, and the pulverized powder is collected by the collection device and sent to the next step. FIG. 17 is a process flow diagram showing an embodiment of a closed circuit type powder processing facility.

  The classifier classifies the fine particles by using the fact that the sedimentation speed of the solid particles in the airflow varies depending on the size of the particles. However, the larger the irregularities of the particles, the larger the surface area, so the sphericity becomes smaller. The smaller the sphericity, the larger the resistance coefficient against the Reynolds number, and the same resistance coefficient as the smaller particles. Therefore, in the classifier, the poorly shaped particles that require circulation processing are regarded as small particles and are discharged to the collection device and mixed into the processed powder, so that the sphericity deteriorates and the powder processing equipment Yield gets worse.

  In a closed circuit type powder processing facility, the particle size of the pulverized product is determined by a classifier. In general, since the particle shape tends to be spherical when pulverized for a long time with a weak force, the sphericity of the particles can be improved by loosening the processing conditions of the pulverizer. However, when the rotor speed of the pulverizer is decreased to reduce the pulverization speed, the number of powder circulation increases and the productivity decreases.

The amount of powder passing through the pulverizer is the sum of the raw material supply amount and the powder circulation amount. When the rotation speed of the pulverizer rotor is increased, the powder becomes finer in the pulverizer and the amount of powder circulation is reduced.
At the start of operation, the discharge amount is smaller than the raw material supply amount, and the circulation amount continues to increase thereafter. However, the increase amount gradually decreases, and eventually, the supply amount and discharge amount become the same, and it has been processed by stable continuous processing. Production of powder. Since the particle size of the product powder is determined by a classifier, there is no variation in particle size, but the sphericity varies.
If the pulverizer does not have the ability to reduce the powder to a predetermined particle size, the amount of circulation continues to increase and the power continues to increase.

Note that Patent Document 2 discloses a facility in which a pulverizer is provided upstream of a surface treatment apparatus to continuously perform pulverization and surface treatment. In the disclosed facility, the number of devices can be reduced and the facility cost and the operation cost can be reduced by processing two processes continuously with one facility.
In order to obtain a fine powder product with high sphericity by the facility described in Patent Document 2, the shape of the particles at the stage of passing through the pulverizer is important. In the facility described in Patent Document 2, a pulverizer that matches the raw material characteristics and the required particle size or particle size distribution is selected, but the obtained particle shape depends on the characteristics of the pulverizer, and the sphericity is appropriately set. It is difficult to adjust.

  FIG. 7 of Patent Document 2 describes an example of closed circuit pulverization in which a classifier is provided in a pulverizer, and powder having a large particle size is selected, circulated, and pulverized again. Although it is possible to improve the sphericity of the pulverized product in the disclosed closed circuit pulverization part, the reach limit of the sphericity is low, and the condition is that it does not affect the operation of the continuously connected surface treatment equipment. The width is small. Further, as a characteristic of the classifier, if the sphericity is low, classification is performed assuming that the particle size is smaller than the actual particle size, so it is necessary to supply particles having a predetermined particle size.

JP 2007-130627 A JP 2009-090255 A

As described above, as the use of fine powder spreads, there has been a strong demand for improvement in powder shape and improvement in efficiency of powder processing equipment. In response to such demands, for example, according to a closed circuit type powder processing facility using a pulverizer, the particle size of the powder is determined by the classifier, and the powder particles slightly improve the sphericity, but the circulation of the powder As the number of times increases, power efficiency decreases.
Accordingly, an object of the present invention is to provide a powder processing facility and a powder processing method which can efficiently obtain a pulverized product having a high sphericity by pulverizing a powder to a target particle size.

  In order to solve the above problems, at least two powder processing facilities according to the present invention are a powder supply tank used for supplying raw material powder and the other a powder storage tank used for storing processed powder. A powder tank, a pulverizer for pulverizing the raw material powder, a powder supply machine for supplying the raw material powder from the powder supply tank to the pulverizer, and receiving the powder processed by the pulverizer A collection device that separates and collects the body from the carrier air and a control device, and by the control device, the powder storage tank stores the collected powder, and the stored powder is used as the next powder. The raw material powder for processing is configured to be supplied to a pulverizer through a powder feeder.

  The powder processing method according to the present invention includes a step of setting pulverization conditions in the next powder processing, a step of supplying raw material powder from a powder supply tank to a pulverizer by a powder feeder, and a pulverizer. A step of collecting the collected pulverized powder by a collecting device, a step of receiving the collected pulverized powder in a powder storage tank, a step of determining completion of powder processing, and a step of storing in the powder storage tank And supplying the pulverized powder as raw material powder to a powder feeder.

According to the powder processing facility and the powder processing method of the present invention, first, a predetermined amount of raw material powder is supplied to a pulverizer to perform powder processing, and the pulverized powder collected by the collection device is stored. By repeating the process of powder processing using the stored powder as the raw material powder for the next pass, it is possible to perform powder processing to obtain a product having a target particle size and high sphericity.
According to the powder processing facility and the powder processing method according to the present invention, the particle size of the processed powder is reduced for each pass, and the sphericity is improved. For example, the average particle size of the powder reaches a predetermined value. At that time, the powder can be taken out of the equipment to obtain a product powder having high sphericity.

  It should be noted that the final particle size of the powder can be selected by adjusting the operating conditions of the powder processing apparatus. For example, by setting the rotation speed of the rotor to a low speed, the degree of processing for each pass is reduced and the change in particle size is reduced, but the sphericity is deepened. Further, as the number of repetitive passes increases, the amount of powder that can be processed per unit time increases because the particle size of the powder decreases and the processing amount decreases. Furthermore, the processing efficiency can be improved by increasing the amount of powder supplied per unit time and shortening the processing time.

The pulverizer used in the powder processing facility of the present invention includes a rotor that is supported by a rotating shaft and has a large number of convex portions formed on the outer surface, and a large number of inner surfaces that are fitted with gaps on the outer side of the rotor. And a pulverizing apparatus that pulverizes the powder sucked into the machine together with air between the rotor and the stator more roundly.
This fine pulverizing device gradually pulverizes the powder with a weaker force by lowering the rotational speed of the rotor, and smoothes the convex portions on the surface little by little to obtain a round pulverized product. be able to. Moreover, since the processing amount per unit time increases as the particle size of the powder to be processed decreases, the amount of powder supply can be increased.

  The optimum powder processing conditions found for each pass are stored in the storage device, and each time the path advances, the conditions that match the new path are read from the storage device and automatically set. Thus, it is possible to efficiently produce a powder having a preferable particle size and improve the sphericity of the powder. Further, since the processing speed is improved when the pass advances and the particle size is reduced, the supply rate of the raw material powder to be powder-treated can be increased and the production efficiency of the product powder can be improved.

  The powder-treated powder in the powder storage tank may be temporarily moved to the powder supply tank and supplied from the powder supply tank to the pulverizer. In addition, by switching the piping connection between the powder supply tank and the powder storage tank, the powder-treated powder is supplied as raw material powder directly from the tank that was the powder storage tank to the pulverizer via the powder supply machine. Then, the powder-treated powder collected by the collection device may be stored in a tank that was an empty powder supply tank by sending out all the contents.

Note that the powder feeder may be provided exclusively for each of the powder supply tank and the powder storage tank.
The powder storage tank may be provided at a position higher than the powder supply tank, and the powder-treated powder may be moved by dropping it into the powder supply tank.
Furthermore, the collection device may be arranged at a position higher than the powder storage tank, and the collected powder may be dropped into the powder storage tank.
The lower part of the collection device can be made into a container and used as a powder storage tank or a powder supply tank.

In the powder processing facility according to the present invention, a suction device is provided to generate an air flow from the outlet of the powder supply machine to the collection device via the pulverizer, and the generated air current turns the raw material powder into the pulverizer. The supplied powder-treated powder may be conveyed to a collection device.
The collected powder-treated powder is transferred from the collection device to a powder storage tank. When the collection device is installed at a position higher than the powder storage tank, it can be moved using natural fall. Also, a suction device that sucks the inside of the powder storage tank is provided to generate an air current from the tip of the duct below the collection device to the powder storage tank, and is intermittently discharged by a double damper below the collection device. The treated powder can also be conveyed in this air stream. When using the air current transport, the height relationship between the tanks is not restricted, so the degree of freedom in the arrangement in the facility is expanded.

The powder processing facility according to the present invention is provided with a control device having a sequence control function, and can operate an operation device such as a valve or a motor in the facility in a predetermined order so that the facility can be automatically operated. it can. The control device may be a sequencer that operates the operation devices in a predetermined order, or a small electronic computer that includes an input / output interface and handles the operation devices based on logical calculations.
For example, optimum values for various parameters necessary for the operation of the powder processing apparatus may be given in advance for each condition and stored in the storage device.

  In the powder processing facility according to the present invention, after the raw material powder sent from the powder supply tank is pulverized by the pulverizer and stored in the powder storage tank based on the command signal of the control device, this time, The powder-treated powder stored in the body storage tank is transferred to the powder supply tank. The powder-treated powder is supplied as a raw material powder to a pulverizer, and the powder generated by the pulverizer is transported to a powder storage tank via a collection device. By repeating this cycle as many times as necessary, a powder product having a desired particle size distribution and a higher sphericity than the conventional one is obtained.

The pulverizer in the powder processing facility of the present invention is an effect of the present invention particularly when the pulverization is performed by scraping the corners little by little with a weak force and the sphericity is increased according to the number of treatments. Becomes prominent.
The collection device may be a cyclone separator and / or a bag filter.
The product powder may be unloaded from the powder storage tank or unloaded from the collection device.
A cooling device for cooling the conveying airflow can be provided in the supply pipe of the pulverizer.

The powder supply tank and the powder storage tank have the same configuration and can be used by switching the roles of powder supply and powder storage for each pass by switching the pipes. In addition, a powder storage tank may be disposed on the powder supply tank, and the contents of the powder storage tank may be moved to the powder supply tank when moving to the next pass.
A raw material tank that receives the raw material powder from the previous step may be provided separately, and a predetermined amount of the raw material powder may be supplied from the raw material tank in the first cycle. By providing the raw material tank, it is possible to continuously receive the raw material supply from the previous process regardless of the cycle stage.

  The optimum operating conditions of the pulverizer are not constant, for example, the rotational speed of the rotor varies depending on the target particle size, or the amount supplied to the pulverizer can be increased when the particle size of the powder to be processed becomes small. . Therefore, the optimum operating condition of the pulverizer is confirmed in advance for each pass by a test, etc., and the operating condition is stored in the storage device of the control device, and the control device operates the pulverizer according to the optimum operating condition for each pass. Can be done.

Further, a particle size measuring device that measures the particle size of the processed powder in-line may be provided, and the measurement result may be used for quality determination of the control device, that is, end point determination.
It is also possible to set a target quality at an intermediate stage and control the pulverizer to automatically follow the target value by automatically changing the operating conditions.
Furthermore, the raw material supply amount can be automatically adjusted by feeding back the power and temperature of the pulverizer.

It is a process flow figure showing the 1st example of powder processing equipment concerning one embodiment of the present invention. It is sectional drawing which shows the structure of the typical grinder used by this embodiment. It is a principal part expanded sectional view which shows the cross-sectional shape of the rotor of FIG. 2, and a stator. It is a flowchart explaining the process in the powder processing equipment of this embodiment. It is a graph which shows the relationship between the frequency | count of the pass in the powder processing equipment of this embodiment, the particle size of powder, and circularity. It is a graph which shows the relationship between the frequency | count of a pass in the powder processing equipment of this embodiment, and the maximum processing amount. It is a process flow figure showing the 2nd example concerning powder processing equipment of this embodiment. It is a process flow figure showing the 3rd example concerning powder processing equipment of this embodiment. It is a process flow figure showing the 4th example concerning powder treatment equipment of this embodiment. It is a process flow figure showing the 5th example concerning powder treatment equipment of this embodiment. It is a process flow figure showing the 6th example concerning powder processing equipment of this embodiment. It is a process flow figure showing the 7th example concerning powder processing equipment of this embodiment. It is a process flow figure showing the 8th example concerning powder processing equipment of this embodiment. It is a process flow figure showing the 9th example concerning powder processing equipment of this embodiment. It is a process flow figure showing the 10th example concerning powder processing equipment of this embodiment. It is a process flow figure showing the 11th example concerning powder processing equipment of this embodiment. It is a process flow figure which shows the Example of the conventional powder processing equipment of a closed circuit system.

Hereinafter, embodiments of a powder processing facility and a powder processing method according to the present invention will be described in detail with reference to the drawings.
The powder to be processed in the powder processing facility according to the present invention is not limited to organic and inorganic types, and is represented by toner, graphite, nylon, titanium oxide, etc., and has an average particle size of several hundreds μm or less, particularly a particle size. It is a powder of several μm to several tens of μm. The powder treatment includes pulverization of the powder particles, and includes obtaining powder particles having increased sphericity accompanying the pulverization.

The powder processing equipment of the present invention repeatedly performs powder processing for the purpose of efficiently obtaining fine particles having high sphericity rather than finely pulverizing. In many pulverizers, compared with the case where the rotation speed is increased and the target particle size is pulverized all at once, it is more likely that the rounded particles are more gradually pulverized by passing through a pulverizer having a lower rotation speed. There is a tendency to be obtained.
Therefore, in order to obtain a powder having a high sphericity, repeated powder processing is conceivable in which a product powder is obtained by repeatedly applying a pulverizer under loose pulverization conditions.

  In the present specification, the repeated powder treatment refers to a process of repeatedly collecting and storing the entire amount of the powder processed product that has passed through the pulverizer and supplying the entire amount of the recovered product to the pulverizer again. Also, the process of passing through the pulverizer is called a pass, and the powder that has passed once is called a 1-pass product and if passed twice, it is called a 2-pass product to distinguish. Furthermore, a process of giving raw material powder, repeatedly performing powder processing for a predetermined number of passes, and taking out product powder is called batch.

The powder processing facility of the present invention automatically performs repeated powder processing.
In the case of repeatedly performing powder processing, it is preferable to adjust the operating conditions of the pulverizer so as to obtain a round processed product by gradually pulverizing the powder to be processed with a weak force.

  FIG. 1 is a process flow diagram showing an example of a powder processing facility according to one embodiment of the present invention, FIG. 2 is a cross-sectional view showing the configuration of a typical pulverizer used in this embodiment, and FIG. FIG. 4 is a flowchart for explaining a control algorithm executed by the control device in the present embodiment, and FIG. 5 is a flowchart in the present embodiment. FIG. 6 is a graph showing the relationship between the number of passes, the particle size of the powder, and the circularity, and FIG. 6 is a graph showing the relationship between the number of passes and the maximum processing amount.

  As shown in FIG. 1, the powder processing facility according to the present embodiment has two powder tanks 11a and 11b in which one is a powder supply tank and the other is a powder storage tank, and the supplied powder. A pulverizer 31 that pulverizes the body and supplies powder after powder processing, and a powder that supplies raw powder to the pulverizer 31 from the powder supply tank 11a (11b) and the powder storage tank 11b (11a) Including powder feeders 21a and 21b, and collecting devices 41 and 42 for receiving the powder after the powder treatment supplied from the pulverizer 31 and separating the powder from the carrier gas and collecting the powder. The tank 11b (11a) stores the powder collected by the collection device 41, and the powder supply machine 21b (21a) can supply the powder stored in the powder storage tank 11b (11a) to the pulverizer 31. It is configured as follows.

  The powder processing apparatus 31 may be, for example, a fine pulverizer having a structure as shown in FIGS. The pulverizer shown in FIGS. 2 and 3 includes a rotor 129 having an outer surface that is supported by a rotating shaft 133 that is rotated by a drive belt 135 and that has a large number of convex portions 136, and a gap outside the rotor 129. And a stator 124 having an inner surface fitted with 130 and forming a plurality of convex portions 125.

  A swirling airflow is formed in the gap 130 by the convex portion 125 of the stator 124 and the convex portion 136 of the rotor 129. For this reason, the powder carried into the machine from the supply port 123 by the conveying airflow is slightly crushed while moving through the gap 130 between the rotor 129 and the stator 124 that rotate at high speed, and is discharged as processed powder. 128 is discharged. A jacket for circulating cooling water may be provided to remove heat generated during crushing and perform stable powder processing.

  Further, in the pulverizer employed in this embodiment, the convex portion 125 of the stator 124 and the convex portion 136 of the rotor 129 are both in a direction parallel to the rotation axis of the rotor, as shown in FIG. It forms continuous grooves and is suitable for pulverizing fine powders little by little. However, either or both of the grooves may be continuous in a direction perpendicular to the rotation axis, or may have an appropriate inclination with respect to the rotation axis. Moreover, the convex part may not be continuous but may be divided. Furthermore, it is possible to employ a powder processing machine that has substantially the same configuration and smoothes the surface of the powder particles.

More specifically, a kryptron series (trade name) grinder commercially available from Earth Technica Co., Ltd. can be used as the grinder 31. These crushers basically have the structure shown in FIG. 2, etc., and there are fine irregularities on the outer periphery of the rotor and the inner periphery of the stator, and a gap of about 0.5 to 2 mm is provided between the rotor and the stator. When the processed material conveyed by the airflow passes through the gap while the rotor is rotated at a high speed such as a normal peripheral speed of 100 to 130 m / s and a maximum of about 170 m / s, it is crushed or surface-treated. It has become.
In addition, even if the other powder processing apparatus is an apparatus that reduces the pulverization and processing conditions by loosening the pulverization and processing conditions, the sphericity of the powder particles is improved. It can be applied to the powder processing equipment of this embodiment.

  The powder processing facility in the present embodiment is attached with a control device 81, collects signals from various sensors in the facility, judges the state of the facility, and performs various types of operations in the facility according to a predetermined sequence. Appropriate operation signals are given to the operating device to smoothly perform automatic operation of the equipment. The control device 81 is attached with a storage device 82 for storing parameter values that meet the conditions and an operation panel 83 for inputting operator instructions.

  The powder processing equipment includes a step of supplying the raw material powder from the powder supply tank 11a (11b) to the pulverizer 31 by the powder supply device 21a (21b), and the raw material powder is processed by the pulverizer 31. To the processed powder, the process of collecting the processed powder generated by the pulverizer 31 with the collection device 41, and the collected processed powder into the powder storage tank 11b (11a). The accepting step, the step of setting the processing conditions in the next powder processing, and the processed powder stored in the powder storage tank 11b (11a) as the raw material powder in the next powder processing, the powder feeder 21b. The powder process including the process of supplying to (21a) is performed.

Specifically, for example, the steps shown in FIG. 4 are sequentially and repeatedly executed using the sequence control function provided in the control device 81.
In the process illustrated in FIG. 4, first, when the raw material powder to be processed is received from the outside into the powder supply tank 11a (11b) (S01: raw material reception), preparation for start-up is performed. In the start-up preparation, the blower as the suction device 51 is started, passes from the cooler 52 through the discharge parts of the powder feeders 21a and 21b, passes through the pulverizer 31, and the cyclone separator 41 of the collection device. The conveying airflow passing through the bag filter 42 is formed, and the pulverizer 31 is started (S02: preparation for start-up).

Next, the conditions of the path to be carried out are confirmed, and parameters relating to each element in the equipment such as the powder feeders 21a and 21b and the pulverizer 31 are set to values suitable for the path (S03: path). Preparation). When the pass preparation is complete, a drive signal is transmitted to the powder feeder 21a (21b), and the powder adjusted to a predetermined powder supply amount is supplied into the supply pipe to the crusher 31 (S04: raw material supply) ). The powder transported in the transport airflow is subjected to an appropriate powder treatment while passing through the crusher 31 to reduce the particle size and appropriately improve the sphericity, and is discharged to the collection devices 41 and 42 ( S05: Powder processing).
In the cyclone separator 41 of the collection device, the processed powder separated from the fine powder according to the airflow conditions settles at the bottom of the cyclone separator 41. When the fine powder accompanies, the fine powder flows down to the bag filter 42 together with the conveying airflow and is captured by the filter cloth (S06: collection).

  When the pass to be executed is not the final pass (S07: end determination), the powder is dropped and moved from the bottom of the cyclone separator 41 to the powder storage tank 11b (11a) (S08: storage). After that, returning to step S03: path preparation, the operation is repeated from preparation for a new path. On the other hand, if this pass is the last pass (S07: end determination), the powder deposited from the bottom of the cyclone separator 41 is taken out and supplied out of the system as a powder-treated product (S09: product removal). ), The series of operations is terminated (S10). Whether the pass to be executed is final or not can be determined by counting the number of passes and reaching a predetermined number of passes, but by measuring the particle size of the processed powder, It may be determined by determining whether or not the value is reached.

  In the processing in the powder processing facility, first, in the first pass, the raw material is supplied to the pulverizer 31 at a predetermined rate by the powder supply machine 21a to perform the powder processing. The one-pass product after the powder processing is almost entirely collected by the cyclone separator 41 and stored in the powder storage tank 11b via the switching valve 44.

  After the raw material is emptied up to the feeder hopper attached to the powder feeder 21a, the one-pass product stored in the powder storage tank 11b is supplied to the pulverizer 31 as a raw material. Since the one-pass product has already undergone a single powder treatment and the particle size has greatly decreased, the amount that can be processed in the pulverizer 31 has increased. Therefore, the powder raw material supplied via the rotary valve 12b provided at the bottom of the powder storage tank 11b is stored by the powder supply machine 21b connected to the powder storage tank 11b. The entire amount is supplied at a rate commensurate with the amount of powder processing in the second pass.

Since the switching valve 44 switches the flow path from the cyclone separator 41 to the previously empty raw material supply tank 11a, the two-pass product collected after the powder processing is now the raw material supply tank. 11a is stored. After the third pass, the series of steps described above is repeated while switching between the tank for storing the raw material powder and the tank for storing the powder after powder processing for each pass until the designated number of passes is reached.
When the specified number of passes is reached, the switching valve 61 provided under the cyclone separator 41 is switched to the discharge side, and the processed powder collected by the cyclone separator 41 is carried out of the system as product powder. To do.

  In the process of the present embodiment, the raw material powder once supplied passes through the pulverizer 31 once for each pass, undergoes powder processing, and is stored. That is, the raw material powder and the processed powder are not mixed in the pass. Accordingly, all powder raw materials are equally subjected to the powder processing for the number of passes. For this reason, the particle size and sphericity of the raw material powder are improved almost equally as the number of passes increases, and the particle size distribution and sphericity distribution of the product powder become relatively narrow.

The bag filter 42 is a two-stage butterfly valve 46a, 46b provided in the bottom discharge pipe by separating ultrafine powder mixed with the carrier airflow with a filter cloth, dropping it by an appropriate method and collecting it on the bottom. The fine powder can be collected through a double damper composed of
Further, a cooler 52 is provided at the end of the pipe having an opening for sucking the atmosphere by the suction device 51 so as to cool the transport airflow.

  Further, a double damper composed of two butterfly valves 43a and 43b provided at the bottom of the cyclone separator 41, rotary valves 12a and 12b provided at the bottoms of the raw material supply tank 11a and the powder storage tank 11b, The rotary valves 22a, 22b and the like provided at the discharge ports of the powder feeders 21a, 21b are necessary so as not to disturb the pressure in the containers.

FIG. 5 is a graph showing the results of examining how the particle size and sphericity change depending on the number of passes in the powder processing facility of this embodiment.
FIG. 5 shows a comparison of the relationship between the number of passes, the granularity, and the sphericity when the final pass number is selected as 2, 5, 7, and 10. The particle size greatly decreases in the first pass, and thereafter the diameter decreases exponentially. However, in all cases, the rotor rotation speed and the powder supply rate of the powder processing apparatus 31 are selected so that the particle sizes are almost the same in the final stage. Yes.

On the other hand, from the graph of sphericity (in order to estimate the sphericity of the particle by measuring the circularity of the projected image of the particle, FIG. 5 plots the circularity instead of the sphericity), the number of final passes It can be seen that the larger the is, the higher the degree of circularity (that is, the sphericity) reached.
That is, if conditions that cause severe diameter changes in powder processing are used, the same particle size can be reached even if the number of passes is small, but the sphericity cannot be sufficiently increased. Therefore, it was found that in order to sufficiently increase the sphericity of the product powder, it is preferable to increase the number of passes by adopting loose powder processing conditions such as pulverizing little by little.

FIG. 6 is a graph showing how the maximum amount of powder that can be processed by the pulverizer 31 varies according to the number of passes in the powder processing facility of this embodiment. As the number of repeated passes increases, the particle size of the powder to be processed becomes smaller and the sphericity is improved, so that the processable amount of the pulverizer 31 increases. It is shown that when the number of passes is 10, the processable amount is tripled or more.
In addition, since the processable amount of the pulverizer 31 increases, the powder supply rate supplied to the pulverizer 31 can be increased.

  As described above, in the powder processing facility according to the present embodiment, the entire amount collected of the powder processed in each pass is temporarily stored, and the powder processing is repeated as a raw material for the next pass. In order to reduce the granularity to a desired value, the number of passes can be increased under mild processing conditions to improve the sphericity. Further, as the number of passes is increased, the processing load is reduced and the rotational speed of the pulverizer 31 can be reduced, so that the no-load power is reduced and the basic unit is reduced. Furthermore, it is possible to perform repeated processing under optimum conditions by setting the powder processing amount of the pulverizer 31 and the rotational speed of the rotor to optimum values as the path progresses.

  The optimum amount of processing and the number of revolutions for each pass are checked in a prior test, and the values are stored in the storage device 82. The optimum value is read for each pass in production operation and used for setting conditions. In this way, the most efficient powder processing can be performed.

Note that the powder feeders 21a and 21b are preferably of a type that is adjusted so as to have an automatically set supply rate when a set value is provided with a measuring instrument. Furthermore, in order to implement the sequence control by the control device 81, it is more preferable that the remote control operation is possible.
In addition, when the last pass is executed, the raw material powder to be processed in the next batch can be put into the empty powder tank when the raw material supply side powder tank becomes empty. Efficient.

  The powder processing facility of this embodiment temporarily stores the powder processed for each pass in a tank, and again applies the entire amount of powder stored in the next pass to the powder processing. Thus, the sphericity of the powder is improved by the powder treatment formed by repeatedly performing the powder treatment many times. A powder processing facility that repeatedly performs such powder processing can produce powder with high sphericity with a simple configuration mainly using a pulverizer without using a classifier.

FIG. 7 is a process flow diagram showing a second example of the powder processing facility of the present embodiment. In addition, the overlapping description is avoided by using the same reference number for the element which has the same function. The same applies to the third and subsequent embodiments.
In the first embodiment, the powder feeders 21a and 21b are provided independently in the powder supply tank and the powder storage tank, respectively, whereas in this embodiment, only one powder feeder 21a is provided. It is provided and shared by two tanks. There is no difference in other configurations.

  Since the process of supplying the raw material powder using the powder supply machine is only once per pass, when the path is switched, the powder from the powder tank to which the raw material powder should be supplied in that pass is accepted. The pulverizer 31 may be supplied. The powder supply rate is set to an optimum value according to the conditions for each pass by the control device 81. Equipment costs can be saved by reducing the number of powder feeders. However, it is difficult to start the next pass immediately after discharging the raw material powder because the next raw material powder cannot be received by the feeder hopper until all the contents of the powder feeder 21a are discharged.

FIG. 8 is a process flow diagram showing a third example of the powder processing facility of the present embodiment.
In the first embodiment (FIG. 1), the cyclone separator 41 and the bag filter 42 are arranged in series as a collection device, but in this embodiment, the cyclone separator is omitted and only the bag filter 42 is installed. The powder processed with the bag filter 42 is collected. There is no difference in other configurations.

In the cyclone separator, the collected powder can be completely discharged for each pass, so that there is little risk of mixing components with different numbers of passes and contamination when the type of powder to be treated is changed. However, in the cyclone separator, since the total yield is the power of the number of passes in one pass, the yield decreases as the number of passes increases.
On the other hand, with bag filters, there is a problem of adhesion to filters (filter cloths) and cans, and there is a concern that powders with different numbers of passes may be mixed, or contamination with materials with different components may occur. However, all components having a predetermined particle size or more can be collected and recycled.

FIG. 9 is a process flow diagram showing a fourth example of the powder processing facility of this embodiment.
In the first embodiment (FIG. 1), a cyclone separator 41 of a collection device is arranged on two powder tanks 11 which become a powder storage tank and a powder supply tank, and the powder after collection is collected. The body was transferred from the cyclone separator 41 to the powder tank by natural fall.

  On the other hand, in the present embodiment, the cyclone separator 41 is installed at a low position, and the collected powder is transported to the powder tank by an appropriate powder transporting means such as air flow transport. In FIG. 9, the product powder is switched by a switching valve 61 provided in a pipe connecting the cyclone separator 41 and the powder tank 11, and the powder such as air current is transferred to the newly provided product tank 62. It can be transported by means of transport. Further, only one powder feeder 21a is installed, and is shared by the powder storage tank and the powder supply tank. Other configurations are the same as those of the first embodiment.

A suction device 53 provided for the present embodiment sucks the internal air of one of the two powder tanks 11a and 11b through the switching valve. Then, either of the powder tank and the discharge pipe under the cyclone separator 41 is connected via the switching valve 44 interlocked with the switching valve 54 and the double dampers 43a and 43b installed in the discharge pipe at the bottom of the cyclone separator. Airflow is generated between them. Therefore, when the double dampers 43a and 43b are opened and the treated powder collected in the cyclone separator 41 falls into the air stream, the treated powder is put into the selected powder supply tank 11a or the powder storage tank 11b. Be transported.
In the present embodiment, since the cyclone separator 41 can be installed at the floor position, the height of the facility can be suppressed as compared with the installation on the tank. However, the energy efficiency is reduced by the amount of the air transport device.
There are various known methods for transporting the powder, and these can also be used as appropriate.

The product powder flows into the product tank 62 via a switching valve 61 provided in the middle of an air feed pipe from the cyclone separator 41 to the powder tank 11 by a suction device 64 provided for the present embodiment. Be transported. Product powder in the product tank 62 is carried outside through a gate valve 63 provided at the bottom. Since the product tank 62 absorbs fluctuations in demand, it is effective in facilities where the next process is connected.
Further, since the number of tanks to which the powder collected by the cyclone separator 41 is transferred is always one, the suction device 53 and the suction device 64 can be shared.
The product powder may be directly taken out from the bottom of the cyclone separator 41 and supplied to the outside.

FIG. 10 is a process flow diagram showing a fifth example of the powder processing facility of this embodiment.
In the first embodiment, two powder tanks are arranged in parallel, and the powder supply tank and the powder storage tank are switched and used by the switching valve 44. The place which has arrange | positioned the powder storage tank 11c on the body supply tank 11a is different, and there is no difference in another structure. In the drawing, the configuration related to the control device 81 is omitted.

In the present embodiment, the storage tank for the raw material powder and the processed powder can be fixed. The raw material powder is put into the powder supply tank 11a provided on the lower side, and the powder after powder processing is stored in the powder storage tank 11c provided on the upper side. After the lower powder supply tank 11a is emptied, the gate valve 14 is opened to transfer the powder after powder processing in the upper powder storage tank 11c to the powder supply tank 11a. If the powder-treated powder is discharged from the powder storage tank 11c, the next pass operation can be started.
After the pass is repeated a specified number of times, the switching valve 61 provided under the cyclone separator 41 is switched to take it out as a product powder.

  In the present embodiment, since the pipe sections among the cyclone separator 41, the powder storage tank 11c, the powder supply tank 11a, and the powder supply machine 21a are shortened, the tanks in the first embodiment (FIG. 1) are rather arranged in parallel. The height of the facility can be reduced as compared with the case of arrangement. Further, if the movement from the powder storage tank 11c to the powder supply tank 11a is completed before the feeder hopper of the powder supply machine 21a becomes empty, the loss time in the progress of the path can be eliminated.

FIG. 11 is a process flow diagram showing a sixth example of the powder processing facility of this embodiment.
In the fifth embodiment (FIG. 10), the cyclone separator 41, the powder storage tank 11c, the powder supply tank 11a, and the powder supply machine 21a are arranged in the vertical direction, and the powder is transferred by natural fall. The present embodiment is mainly different in that the powder storage tank 11d is arranged on the floor, and the powder is transported from the powder storage tank 11d to the powder supply tank 11a by airflow conveyance. There is no big difference in the configuration.

  In this embodiment, a switching valve 65 under the suction device 53 and the powder storage tank 11d is provided for transfer. When the switching valve 65 is switched so that the pipe between the powder supply tank 11a and the powder storage tank 11d discharge portion is conducted and the inside of the powder supply tank 11a is sucked, a carrier airflow is generated in the pipe. The carrier airflow transfers the powder sent out by the rotary valve 15 at the bottom of the powder storage tank 11d to the powder supply tank 11a.

  In each pass operation, the rotary valve 15 provided at the bottom of the powder storage tank 11d is stopped until all the raw material powder is sent out by the powder feeder 21a, and the processed powder becomes the raw material powder. Avoid mixing. On the other hand, when the designated number of passes is reached and the product powder is discharged, the switching valve 65 is switched, the double dampers 43a and 43b under the cyclone separator 41 are opened, the rotary valve 15 is rotated, and the tank is rotated by the cyclone separator 41. The product powder falling to the bottom passes through the powder storage tank 11d and is directly discharged out of the system.

In this embodiment, the height of the facility can be suppressed. Furthermore, if the product powder is transferred to the product tank by airflow conveyance as shown in FIG. 9, the powder storage tank 11d can be installed at a level near the floor surface, so that the equipment height is further increased. Can be suppressed.
Although the cyclone separator 41 and the bag filter 42 are connected in series as the collection device, the cyclone separator 41 is omitted and the bag filter 42 is used as in the third embodiment (FIG. 8). You may install on the powder storage tank 11d.

FIG. 12 is a process flow diagram showing a seventh example of the powder processing facility of the present embodiment.
This embodiment is different from the first embodiment (FIG. 1) in that a raw material tank is arranged in parallel with two powder tanks which are a powder storage tank and a powder supply tank. There is no difference in other configurations.
In this embodiment, a raw material dedicated tank 16 is provided in parallel with the powder supply tank 11a and the powder storage tank 11b. These tanks 11a, 11b, and 16 are provided with rotary valves 12a, 12b, and 17 at the bottom, and are connected in parallel to the supply pipe of the pulverizer 31 via powder feeders 21a, 21b, and 21c that are independently provided. ing. A rotary valve 22c is also provided in the discharge pipe of the powder feeder 21c provided for the raw material tank 16.

The raw material tank 16 is a tank for receiving and storing the raw material powder repeatedly processed by the powder processing facility of the present embodiment from the previous step and supplying the necessary amount of raw material powder for each batch. It is.
In the first pass of starting the batch, the raw material powder is supplied to the pulverizer 31 by the powder supplier 21c. The powder subjected to the powder treatment is collected by the cyclone separator 41 and stored in the powder supply tank 11a. When the powder processed powder reaches the upper limit of the powder supply tank 11a, the powder supply machine 21c for the raw material dedicated tank 16 is stopped. The upper limits of the powder supply tank 11a and the powder storage tank 11b can be detected by weight meters 13a and 13b and level meters provided in the tank.

In the pulverizer 31, the smaller the powder particle size, the smaller the processing load. Therefore, the first pass indicates the maximum load of this batch.
When the powder-treated powder is stored in the powder supply tank 11a, a part of the powder-treated powder may be stored in the feeder hopper of the powder supply machine 21a attached to the powder supply tank 11a. Good. If the powder is put in the feeder hopper, there is no time loss when the powder feeder 21a is started next time.

Next, as a second pass, the powder supplied from the powder supply tank 11a is supplied to the pulverizer 31 by a predetermined amount by the powder supply machine 21a, and the powder subjected to the second powder processing is supplied to the cyclone. It collects with the separator 41, and this time it stores in the powder storage tank 11b. Further, when there is no powder-processed powder in the powder supply machine 21a being supplied, the third pass is started using the powder stored in the powder storage tank 11b as the raw material powder.
In this way, the powder processing is repeated, and when the final pass is reached, the switching valve 61 in the pipe connected to the bottom of the cyclone separator 41 is switched to take out the product powder to the outside.

In this way, the powder supply machine 21c attached to the raw material dedicated tank 16 and the raw material specialized tank only operates at the start of each batch, and thereafter, the powder supply tank 11a and the powder storage tank 11b are used while being switched. Work is done.
Accordingly, since the raw material powder tank 16 can receive the raw material powder while the raw material powder is supplied to the pulverizer 31, the raw material powder can be always charged into the raw material powder tank 16. Since the raw material powder can be continuously received, it is possible to cope with the case where the previous process performs continuous processing.

  Note that the cyclone separator 41 may be omitted, and the bag filter 42 may be installed on the powder supply tank 11a and the powder storage tank 11b as in the third embodiment (FIG. 8). Further, in this embodiment, the powder supply tanks 11a, 21b, and 21c are attached to the powder supply tank 11a, the powder storage tank 11b, and the raw material dedicated tank 16, respectively. It may be used also.

FIG. 13 is a process flow diagram showing an eighth example of the powder processing facility of this embodiment.
This embodiment is different from the fifth embodiment (FIG. 10) in that a raw material dedicated tank is arranged in parallel with two powder tanks which are a powder storage tank and a powder supply tank. There is no difference in other configurations.
In this embodiment, the raw material dedicated tank 16 is provided in parallel with the series connection of the powder supply tank 11a and the powder storage tank 11c. The powder supply tank 11a and the raw material dedicated tank 16 are connected in parallel to the supply pipe of the pulverizer 31 via the powder supply machine 21a and the powder supply machine 21c, respectively.

  In the first pass of starting the batch, the raw material powder is supplied to the pulverizer 31 by the powder supplier 21c. The powder subjected to the powder treatment is collected by a cyclone separator 41, passed through the upper powder storage tank 11c, and stored in the lower powder supply tank 11a and the feeder hopper of the powder supply machine 21a. When the powder-treated product reaches the upper limit of the powder supply tank 11a, the powder supply machine 21c for the raw material dedicated tank 16 is stopped, and the gate valve 12c provided at the discharge port of the powder storage tank 11c is turned off. close up.

In the second pass, the raw material powder is supplied from the powder supply tank 11a, the processed powder is stored in the powder storage tank 11c, and the raw material powder in the powder supply tank 11a becomes empty. Thereafter, the powder supply machine 21a is stopped, the gate valve 12c is opened, and the powder stored in the powder storage tank 11c and the newly entering powder are stored in the powder supply tank 11a.
In the final pass, the switching valve 61 is switched, and the powder-treated powder is taken out of the system directly from the bottom of the cyclone separator 41 to obtain product powder.
As in the fifth embodiment (FIG. 11), powder conveyance from the cyclone separator 41 to the powder storage tank 11c may be performed by airflow conveyance. In this case, there is an advantage that the equipment height is lowered.

FIG. 14 is a process flow diagram showing a ninth example of the powder processing facility of this embodiment.
In the present embodiment, the raw material powder directly put into the lower powder supply tank 11a of the two powder tanks arranged in series with respect to the configuration of the sixth embodiment (FIG. 11) is temporarily stored. The raw material dedicated tank 16 is disposed, and the in-line particle size measuring device 68 is provided in the pipe that guides the processed powder from the pulverizer 31 to the cyclone separator 41, and other configurations are different. Absent.

In this example, since the raw material tank 16 was used, the timing of receiving the raw material powder became free and the connection with the previous process became easy.
Also, since the in-line particle size measuring device 68 can measure the particle size in real time, the particle size reached for each pass is confirmed, and when the target particle size range is reached, it is determined as the final pass and the repetition process is completed. And can be discharged as product powder.
In other embodiments, the load power or the change in the basic unit is observed by measuring the power of the equipment, etc., and the processing amount (supply rate) in the next pass, the rotor rotational speed of the crusher 31, etc. I was able to.

However, in the present embodiment, by installing the in-line particle size measuring device 68, the next pass is more accurately performed based on the particle size of the powder processed powder in each pass. Can be automatically determined by the control device 81. Since the sphericity of the powder is improved when the number of repetitions is increased, it is preferable that the control device 81 is designed so as to determine the operating conditions in the direction of increasing the number of repetitions.
Note that the raw material dedicated tank 16 is useful in supporting automatic operation because it expands the freedom regarding the supply amount of raw material powder.

FIG. 15 is a process flow diagram showing a tenth example of the powder processing facility of this embodiment.
The present embodiment is essentially similar to the configuration of the eighth embodiment (FIG. 13), but the major feature is that the bag filter is enlarged and the bottom is also used as a powder storage tank. For this reason, it looks as if there are no two powder tanks that are either the powder supply tank or the powder storage tank, but the lower region of the bag filter functions as a powder storage tank. The above two powder tanks exist. An in-line particle size measuring device 68 is provided in a pipe that guides the processed powder from the pulverizer 31 to the bag filter 71.

In the present embodiment, the raw material exclusive tank 16 is provided in parallel with the series connection of the powder supply tank 11a and the bag filter 71 having the bottom part also serving as the powder storage tank. The powder supply tank 11a and the raw material dedicated tank 16 are connected in parallel to the supply pipe of the pulverizer 31 via the powder supply machine 21a and the powder supply machine 21c, respectively.
In the first pass, the raw material powder is supplied from the raw material dedicated tank 16 to the powder processing device 31 by the powder supply machine 21c, and the processed powder which has been subjected to the powder processing by the pulverizer 31 is supplied to the bag filter 71. And stored in the powder supply tank 11a through a gate valve 72 below the bag filter 71. The processed powder may be temporarily stored in the bag filter 71 and transferred to the powder supply tank 11a at an appropriate timing.

In each pass after the second time, until the raw material powder of the feeder hopper of the powder supply tank 11a and the powder supply machine 21a is completely discharged, It is collected by the bag filter 71 and stored at the bottom of the bag filter 71. After all the raw material powder of the feeder hopper is discharged, the gate valve 72 under the bag filter 71 is opened to move all the processed powder stored in the bottom of the bag filter 71 to the powder supply tank 11a.
Therefore, the bottom of the bag filter 71 has the same function as the powder storage tank in the other embodiments.

In the last pass, the pipeline is switched by a switching valve 66 provided in the discharge pipe of the powder supply tank 11a, and the product powder is discharged through the powder supply tank 11a. Although it can be discharged from between the bag filter 71 and the powder supply tank 11a, in this case, since the discharge destination must be a sealed tank, troublesome work is required.
In the present embodiment, since the in-line particle size measuring device 68 is installed, the next pass is further accurately determined based on the particle size of the powder processed powder in each pass. Can be automatically determined by the control device 81.

FIG. 16 is a process flow diagram showing an eleventh example of the powder processing facility of this embodiment.
As in the tenth embodiment, this embodiment includes two bag filters corresponding to a powder supply tank and a powder storage tank, in which the bag filter is enlarged and the bottom portion is also used as a powder tank. Therefore, it is characterized in that it is operated by switching alternately.

In the powder processing facility of this embodiment, as shown in FIG. 16, the raw material dedicated tank 16 is connected to the raw material supply pipe of the pulverizer 31 via the powder supply machine 21c. The exhaust pipe for the processed powder of the pulverizer 31 is connected to the intake ports of the two bag filters 73a and 73b via the switching valve 32. The two bag filters 73a and 73b have an enlarged lower space and form a powder tank that can store a large amount of collected powder.
The pipes connected to the bottoms of the two bag filters 73a and 73b are provided with gate valves 74a and 74b, respectively, and further provided with rotary valves 75a and 75b and switching valves 67a and 67b. The switching valves 67a and 67b are used to switch the pipeline between the powder feeders 21a and 21b and the product powder outlet. The powder supply ports of the powder supply machines 21a and 21b are connected to the raw material supply piping of the pulverizer 31 via the rotary valves 22a and 22b.

  The suction device 51 passes through the raw material supply pipe from the cooler 52, passes through the pulverizer 31, passes through one of the bag filters 73a and 73b selected by the switching valve 32, and passes through the exhaust pipes of the bag filters 73a and 73b. As a result, a carrier airflow that is released to the atmosphere by the suction device 51 is formed. The switching valve 55 in the exhaust pipes of the bag filters 73a and 73b is interlocked with the switching valve 32 so that the bottom of one bag filter functions as a powder raw material supply tank and the bottom of the other bag filter is used as a powder. It functions as a storage tank.

  In the powder processing facility of the present embodiment, when a predetermined amount of raw material powder is supplied from the raw material dedicated tank in the first pass, the processed powder produced by the pulverizer 31 is supplied to one bag filter and captured. The collected powder falls to the bottom and is stored as a one-pass product. In the second pass, the one-pass product is supplied to the pulverizer 31 at an appropriate supply rate using the bottom of the bag filter storing the processed powder as a powder supply tank. The powder that has been subjected to the powder processing by the pulverizer 31 is changed in flow path by the switching valve 32, and is then supplied to the bag filter that was not used last time, collected, and stored as a 2-pass product at the bottom of the bag filter. To do.

In the third pass, the bag filter in which the two-pass products are collected is used as a powder supply tank, and the powder supplied to the pulverizer 31 and subjected to the powder treatment is changed in flow path by the switching valve 32. It is supplied to the bag filter that was not used in the second pass, collected, and stored as a 3-pass product at the bottom of the bag filter.
In this way, when the final pass is reached, the product powder is carried out from one of the bag filters via the switching valve 67a (or 67b). When the product powder is discharged from the bag filter in which the powder is stored at the bottom, it can be discharged under atmospheric pressure and the discharge time can be secured. Note that three powder feeders 21 are provided independently for the raw material tank 16 and the bag filters 73a and 73b, respectively. However, the single powder feeder 21a can also be used.

The powder processing facility of the present embodiment switches the air flow conveying pipes of the two bag filters 73a and 73b with the switching valves 32 and 55, and uses them by switching to the powder supply tank and the powder storage tank. The number of equipment will be reduced and the equipment will be simplified.
However, the bug filter has problems that it is not easy to completely separate it from the filter cloth, and that mixing of old and new products becomes a problem when changing the type of processed powder. However, the yield can be greatly improved by using the bag filter as compared with the case where the yield is greatly lowered when the cyclone separator is used for repeated processing.

  The powder processing equipment and powder processing method of the present invention are applicable to foods and pharmaceutical raw materials, carbon-based materials such as graphite and coke, resin-based chemical products such as resins and toners, other metals and minerals, organic and inorganic materials. It can be used to improve the sphericity of various fine powder materials.

11 Powder tanks 11a, 11b, 11c, 11d Powder supply or tank powder storage tanks 12a, 12b Rotary valves 13a, 13b Weigh scale 14 Gate valve 15 Rotary valve 16 Raw material tank 17 Rotary valves 21a, 21b, 21c Powder Feeder 22a, 22b, 22c Rotary valve 31 Pulverizer 32 Switching valve 41, 42 Collection device 41 Cyclone separator 42 Bag filter 43a, 43b Double damper 44 Switching valve 46a, 46b Double damper 51 Suction device 52 Cooler 53 Suction device 54 Switching valve 55 Switching valve 61 Switching valve 62 Product tank 63 Gate valve 64 Suction device 65 Switching valve 66 Switching valve 67a, 67b Switching valve 68 In-line particle size measuring device 71 Bag filter 72 Gate valve 73a, 73b Bag filter 74a, 74b Gate valve 75 , 75b rotary valve 81 control device 82 storage device 83 control panel 123 supply port 124 stator 125 protrusion 128 outlet 129 rotor 130 gap 133 rotary shaft 135 drive belt 136 protrusions

Claims (16)

At least two powder tanks having at least one powder supply tank and at least one other powder storage tank;
A pulverizer for pulverizing the supplied powder and carrying out the pulverized powder;
A powder feeder for supplying raw powder from the powder tank to the pulverizer;
A collecting device that receives the powder after pulverization carried out from the pulverizer and separates and collects the powder from the carrier gas;
A control device,
The control device causes the powder storage tank to store the powder collected by the collection device, and causes the powder supply machine to supply the powder stored in the powder storage tank to the pulverizer. Powder processing equipment configured in The pulverizer has a setting function of pulverization conditions, the powder supply machine has a function of setting a powder supply rate,
The controller adjusts the powder supply rate of the powder supply machine and the pulverization conditions of the pulverizer before supplying the raw material powder, and stores the powder supply tank in the powder storage tank. powder directly or powder processing equipment according to claim 1, characterized in that supplied to the pulverizer after moving to the powder feed tank. 3. The powder processing facility according to claim 1, wherein the control device determines the end of the powder processing, and when the powder processing is completed, the powder after the crushing is taken out as a product. .

The crusher
A rotor that is supported by a rotating shaft and has a large number of protrusions on the outer surface;
A stator which is fitted with a gap on the outside of the rotor and has a large number of convex portions on the inner surface, and
It is a fine grinding device for crushing the powder carried into the machine by air current between the rotor and the stator,
The powder processing facility according to any one of claims 1 to 3, wherein   The powder storage tank is disposed on the powder supply tank, and the powder stored in the powder storage tank is supplied to the powder supply machine via the powder supply tank. The powder processing equipment according to any one of claims 1 to 4.   5. The collection device according to claim 1, wherein the collection device is configured such that a lower body portion is formed into a container and the lower body portion functions as the powder storage tank or the powder supply tank. 6. Powder processing equipment.   The said powder supply machine is comprised by the supply machine provided independently in each of the said powder supply tank and the said powder storage tank, The any one of Claim 1 to 4 characterized by the above-mentioned. Powder processing equipment.   The powder processing facility according to any one of claims 1 to 4, wherein the collection device is arranged at a position higher than the powder storage tank.   The powder processing facility is further provided with a transfer device for transferring the collected powder from the collection device to a powder tank selected as a powder storage tank among the at least two powder tanks. The powder processing facility according to any one of claims 1 to 4, wherein   The transfer device includes a suction device that sucks air in a powder tank selected as the powder storage tank, and the air flow generated by the suction device causes the air to be generated from the collection device to the selected powder storage tank. The powder processing facility according to claim 9, wherein the collected powder is transferred.   11. The powder processing equipment according to claim 1, wherein the collection device is configured by connecting a cyclone separator and a bag filter in series.   The powder processing facility further includes a particle size measuring device provided in a pipe between the pulverizer and the collection device, and compares the measurement result of the particle size measuring device with a target particle size to determine the end point of the processing. The powder processing facility according to claim 1, wherein the powder processing facility is determined.   The powder processing facility further includes a raw material dedicated tank for receiving the raw material powder and another powder feeder connected to the raw material dedicated tank, and the raw material powder initially supplied to the pulverizer is the raw material dedicated tank The powder processing facility according to any one of claims 1 to 12, wherein the powder processing facility is supplied from the plant. A process for setting processing conditions in powder processing;
B process for supplying raw material powder from the powder supply tank to the pulverizer by the powder supply machine;
C process which pulverizes raw material powder with a pulverizer to form a processed powder;
D step of collecting the processed powder generated by the pulverizer with a collection device;
E process for receiving the collected processed powder in a powder storage tank;
When the completion of the powder processing is determined and the powder processing is not completed, the F step that advances to the next G step;
A powder processing method including a G step of supplying processed powder stored in a powder storage tank to a powder feeder as a raw material powder in the next powder processing.   15. The step F determines whether or not the set number of repetitive passes has been reached, and proceeds to the step G when the set number of passes has not been reached. Powder processing method.   In the F step, it is determined whether or not the processed powder generated by the pulverizer has reached a set particle size, and when the processed powder does not reach the set particle size, the G The powder processing method according to claim 14, wherein the process proceeds to a process.

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