JP2003245858A - Magnetic force separating method and apparatus for magnetic grinding material, high-purity recovery method and apparatus for low-melting point glass, and magnetic grinding material used for said method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To separate and recover high-purity low-melting point glass from machined powder of low-melting point glass relatively easily and surely by removing a grinding material from the machined powder. <P>SOLUTION: A reusable magnetic grinding material is classified by a classifying means 2 from mixed powder compressed of the magnetic grinding material and machined powder of low-melting point glass, which is generated by a blast apparatus body 1 and is recovered. Then, the mixed powder composed of the crushed grinding material and the machined powder of low-melting point glass, is guided with an air flow into a magnetic force separating apparatus 5 (5a, 5b) having a separating chamber 51, in which collecting tubes 52 with inserted magnets are arranged at a plurality of prescribed intervals. The guided mixed powder is made to pass between the collecting tubes 52, where the crushed grinding material mixed in the mixed powder is made to stick to the collecting tubes 52 to collect the grinding material. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for separating a magnetic abrasive material which collects and separates the crushed magnetic abrasive material mixed in the cutting powder of the low melting glass by magnetic force in the cutting process of the low melting glass by blasting. Method and separation apparatus, and method and apparatus for recovering low-melting-point glass cutting powder from which crushed magnetic abrasive is removed with high purity by the method and apparatus, and these Regarding the magnetic abrasive used for the means, for example, when a partition wall of a display such as a plasma display panel (hereinafter referred to as “PDP”) or a partition wall material made of low melting point glass used for electrode formation is patterned by sandblasting. Method and device for recovering low melting glass that has been cut and discarded into a highly pure state that can be recycled, and Serial on the magnetic abrasive.

[0002]

2. Description of the Related Art As a method of patterning a partition wall material made of low melting point glass used for forming partition walls of a PDP, first, a low melting point glass paste is applied on a glass substrate by screen printing or a coater and dried, and then the low melting point glass paste is applied. A pattern is formed with a photosensitive resist for sandblasting on the partition material of melting point glass, and blasting is performed using an inorganic powder such as calcium carbonate, glass beads, alumina, etc. as a grinding material using a sandblasting device. After cutting the other parts, the resist is peeled off and the low melting point glass is baked to form partition walls.

A general abrasive material and dust collecting device used in such blasting will be described with reference to FIG. 6. The abrasive material sprayed in the blasting device 1 and generated by being cut by the abrasive material. The cut powder is drawn into the classifying unit 2 by being drawn by the negative pressure of the classifying unit 2 composed of a cyclone or the like, and the reusable abrasive is collected in the classifying unit 2 and supplied to the blasting apparatus main body 1 again. To be done.

On the other hand, the crushed abrasive and the cutting powder of the workpiece are introduced into the dust collector 4 together with air, and are collected in the dust collector 4.

As described above, in the processing method of forming the partition wall by sandblasting, the cutting powder of the low melting point glass scraped from the glass substrate and the sprayed abrasive material are crushed and cannot be recovered by the classifying means 2. Since it was mixed with the abrasive, it could not be reused, and the low melting glass collected in the dust collector 4 was discarded.

Particularly in the process of forming partition walls as high-definition ribs of PDP, about 75% of the applied low-melting glass is cut, so 75% of the low-melting glass used is discarded and used as PDP. Only 25% are done.

Therefore, when the partition wall is formed by sandblasting as described above, a large amount of expensive low-melting glass is currently discarded, which increases the manufacturing cost of the PDP and cannot effectively use resources. .

Further, since the low melting glass used as the partition wall material contains harmful lead glass, it cannot be easily discarded, and the low melting glass is made to be lead-free. It is considered to use bismuth other than lead for glass, but bismuth is a rare metal and expensive, so the material cost rises, and more expensive raw materials as cutting powder than the low-point glass mentioned above are used in large amounts. It will be discarded.

Therefore, the need to recycle the low-melting glass recovered as cutting powder has been emphasized. However, when the low-melting glass is cut by sandblasting, the grain size is about 3 to 5 μm.
m cutting powder is generated at 200g / 1m ² / 1h per nozzle, while calcium carbonate, glass beads, alumina, etc. Approximately the same diameter of about 3-5 μm
Since the amount of abrasives generated by each nozzle is about 300g / 1h per nozzle, the ratio of the abrasive powders in the collected mixed powders is as high as about 60wt%. Makes it difficult to separate.

Due to these problems, it has been required to develop a processing method, an apparatus and a recycling method of low melting point glass that can relatively easily separate and recover the abrasive and the low melting point glass from the recovered dust. It was

In order to meet such demands, a method has been proposed in which magnetic metal particles are used as an abrasive to separate the abrasive and the low melting point glass by utilizing magnetic force (Japanese Patent Laid-Open No. 2001-2001). -122644).

[0012]

As described above, by using the magnetic powder as the abrasive, it becomes possible to separate the abrasive and the low melting point glass by magnetic force, and crush the recovered dust. It became possible to recover the relatively high-purity low melting glass by removing the abrasive.

However, Japanese Patent Laid-Open No. 2001-122644 described as the above-mentioned prior art does not disclose the details of the method and apparatus therefor.

When an iron-based metal is used as the magnetic abrasive, the particle size of the crushed abrasive is 2 μm even if the recovered powder component is 99% low melting point glass. In the following cases, the product manufactured by using the recovered low-melting-point glass is oxidized as a grinding material contained therein during the firing to turn red, and this is used as a partition material of the PDP. It cannot be used.

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and is a mixture of crushed abrasive and cutting powder of low melting point glass, which are generated during blasting. From powder, relatively easily,
In addition to providing a method and an apparatus for separating and recovering the crushed magnetic abrasives reliably, the magnetic abrasives remaining in the cutting powders of the low melting point glass from which the magnetic abrasives have been removed are further removed to obtain a high level. By providing a method and an apparatus for recovering low-melting-point glass with high purity, it is possible to recover cutting powder of high-purity low-melting-point glass with a mixing ratio of preferably crushed magnetic abrasives of 0.2% or less. The purpose of the present invention is to make it possible to effectively reuse the cutting powder of low-melting-point glass recovered without causing reddening due to firing, again as a raw material of a partition material in PDP or the like.

[0016]

In order to achieve the above-mentioned object, a magnetic force separating method for a magnetic abrasive of the present invention provides a method for blasting a substrate formed by applying and drying a low melting point glass paste with a magnetic abrasive. From the mixed powder of the generated magnetic abrasive and cutting powder of low melting point glass, the reusable magnetic abrasive is classified and recovered, and the mixed powder after recovering the reusable abrasive The body is suitably passed through a wire mesh of 5 to 200 mesh, preferably 50 to 150 mesh, more preferably 70 to 130 mesh, then
The flow velocity of this air flow is, for example, 3 to 30 m / sec, preferably 8 to 12 m / sec, together with the air flow in the separation chamber 51 in which a plurality of collection tubes 52 in which magnets are inserted are arranged at predetermined intervals.
Is introduced and passed through the space between the collection tubes 52, and the crushed magnetic abrasive mixed in the mixed powder is attached to the collection tubes 52 and collected.

In order to collect the crushed magnetic abrasive collected in the separation chamber 51, the introduction of the mixed powder into the separation chamber 51 is stopped, and then the magnet in the collection tube 52 is pulled out. Alternatively, when the magnet is an electromagnet, the energization of the electromagnet is stopped, and then the separation chamber 51
The air inside is sucked to recover the crushed magnetic abrasive collected in the separation chamber 51.

When magnetic separation of the magnetic abrasive is continuously performed, at least two separation chambers 51, 51 are arranged in parallel, and the mixed powder is introduced into one separation chamber 51. During the operation, the introduction of the mixed powder to the other separation chamber 51 is stopped and the crushed magnetic abrasive collected in the separation chamber 51 is removed from the separation chamber 5
When the mixed powder is introduced into the other separation chamber 51 while being discharged and collected outside the first separation chamber 51,
It is also possible to stop the introduction of the mixed powder into the separation chamber 51 and discharge the crushed magnetic abrasive collected in the one separation chamber 51 to the outside of the separation chamber 51 for recovery.

In the case of performing the above-mentioned magnetic force separation, the magnetic abrasive is subjected to a processing pressure of 0.0 during the blasting.
The magnetic abrasive is preferably sprayed at 1 to 0.3 MPa (claim 6), and the magnetic abrasive has a lower hardness and a lower oxidative property, and has a carbon content of 0 to 0.3% and an average. Particle size 5-50
It is preferable to use an abrasive having a size of μm.

Further, the magnetic force separating apparatus for magnetic abrasives of the present invention for carrying out the above method introduces a mixed powder of the magnetic abrasive and the cutting powder of the low melting point glass, which is generated in the blasting device 1, and introduces this mixture. The mixed powder after the reusable magnetic abrasive is removed by the classifying unit 2 that classifies and collects the reusable magnetic abrasive from the powder is communicated with the classifying unit 2. Introduction port 54 and the introduction port 5
4, a separation chamber 51 through which the mixed powder introduced together with the air flow passes, and a discharge port 55 for discharging the mixed powder passing through the separation chamber 51 with the air flow out of the separation chamber 51. A plurality of collecting tubes 52 in which magnets are inserted are provided in the separation chamber 51 at predetermined intervals.

Inside the separation chamber 51, a wire net of 5 to 200 mesh is provided upstream of the position where the collecting pipe 52 is arranged to partition the inside of the separation chamber 51 in a direction orthogonal to the flow direction of the air flow. It is preferable that the collecting tubes 52 are arranged at intervals of 3 mm to 10 mm.

Further, by making the magnet removable from the collecting tube 52 or by using an electromagnet as the magnet, it is possible to easily collect the magnetic abrasive collected in the collecting tube 52.

The high-purity recovery method for low-melting glass according to the present invention is the above-mentioned magnetic abrasive and low-melting glass, which are generated when blasting a substrate formed by applying and drying a low-melting glass paste with a magnetic abrasive. Of the reusable magnetic abrasive from the mixed powder with the cutting powder of No. 1 and the step of collecting the reusable magnetic abrasive, and crushing mixed into the mixed powder after collecting the reusable abrasive by the above step A primary separation step of separating the magnetic abrasive by magnetic force, and a secondary separation of the crushed magnetic abrasive that is still mixed in the removed mixed powder of the crushed magnetic abrasive by the primary separation step by the magnetic force. It is characterized in that it includes a separation step, and collects the cutting powder of the low melting point glass from which the magnetic abrasive crushed in the step is removed.

In this high-purity recovery method of low melting point glass, the mixed powder that has undergone the primary separation step is introduced into the dust collector 4 and recovered, and the mixed powder once recovered by the dust collector 4 is collected. The secondary separation step may be performed, or the mixed powder that has been subjected to the primary separation step may be directly subjected to the secondary separation step without being once recovered from, for example, an air flow.

This primary separation step can be performed by the magnetic separation method of the magnetic abrasive material described above, and in the secondary separation step, the mixed powder after the primary separation step is attached to the outer wall with a magnet. It can be carried out by injecting into the cyclone of the non-magnetic material together with the air flow to adhere the crushed magnetic abrasive to the inner wall of the cyclone.

Further, the high-purity recovery apparatus for low melting point glass of the present invention recovers reusable magnetic abrasive material from the mixed powder consisting of the magnetic abrasive material and the cutting powder of low melting point glass generated in the blasting apparatus 1. Primary separation for introducing the classifying means 2 and the mixed powder after the reusable magnetic abrasive is removed by the classifying means 2 and separating the crushed magnetic abrasive in the mixed powder by magnetic force. The apparatus is characterized by including a device and a secondary separating device for separating by magnetic force the crushed magnetic abrasive that is still mixed in the mixed powder from which the magnetic abrasive crushed by the primary separator has been removed.

The low-melting-point glass high-purity recovering apparatus introduces the mixed powder from which the crushed magnetic abrasive has been removed by the primary separating device together with the air flow, and removes the mixed powder from the air flow. It is also possible to provide a dust collector 4 for collecting.

As the primary separating device, the magnetic separating device 5 (5a, 5b) of the magnetic abrasive material described above can be used. In this case, this magnetic separator 5 (5a,
5b) is arranged between the classifying means 2 and the secondary separating device 6 to form a primary separating device, and the outlet of the classifying means 2 is branched to introduce the plurality of magnetic force separating devices 5a, 5b. 54, 54, respectively, and the discharge port of the classification means 2 located upstream of the magnetic force separation devices 5a, 5b can be selectively communicated with any one of the plurality of magnetic force separation devices 5a, 5b. Alternatively, the switching valve 9 may be provided.

The secondary separating device 6 includes a blast gun 61 which mixes the mixed powder that has passed through the primary separating device with an air flow and injects it, and a mixed powder which is injected by the blast gun 61 together with the air flow. Alternatively, the cyclones 62 and 63 made of a non-magnetic material for introducing the magnet and the magnet 64 arranged on the outer circumference of the cyclones 62 and 63 may be used.
Further, as the above-mentioned magnetic abrasive, precipitation hardening type or ferritic type heat resistant stainless steel, preferably SUS
630, and more preferably SUH21 can be used.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described below with reference to the accompanying drawings.

[High Purity Recovery Device for Low Melting Glass] In the present embodiment, the magnetic separation device 5 (5a, 5b) is provided between the classification means 2 and the dust collector 4 in the recovery device shown in FIG. This magnetic force separation device 5
The high-purity recovery device for low-melting-point glass of FIG. 1 equipped with (5a, 5b) as a primary separation device further removes magnetic powder still remaining in the powder recovered by the dust collector 4,
The secondary separation device 6 for recovering 9.8% or more of low melting point glass is provided.

In the low-melting-point glass high-purity recovery apparatus shown in FIG. 1, the mixed powder from which the magnetic abrasive has been crushed by the primary separating device composed of the magnetic separator 5 (5a, 5b) is used. After the dust collector 4 once collects, the collected mixed powder is introduced into the secondary separation device. However, the mixed powder that has passed through the primary separation device is directly introduced into the secondary separation device 6. The configuration may be such that the configuration is not limited to the example shown in FIG.

[Magnetic Force Separation Device] The magnetic force separation device 5 described above.
(5a, 5b) is provided in the pipe between the classifying unit 2 and the dust collector 4, and separates and removes the crushed magnetic abrasive from the powder introduced from the classifying unit 2 into the dust collector 4 together with the air. An example of this magnetic force separation device is shown in FIGS.

As shown in FIGS. 2 to 5, the magnetic separation device 5 (5a, 5b) of the present invention has a separation chamber 51 inside which the mixed powder discharged from the classifying means together with the air flow can be introduced. In this separation chamber 51, a large number of collecting tubes 52 each having a cylindrical body into which a magnet is inserted are arranged, and the crushed magnetic abrasive material is attached to the outer circumference of the collecting tubes 52 to collect them. By doing so, the crushed magnetic abrasive is removed from the air flow that passes through the separation chamber 51 and is introduced into the dust collector 4.

In the present embodiment, the magnetic force separating device 5 (5a, 5b) has two side plates 53a, 53b having an octagonal shape with the diamond-shaped corners removed as shown in FIG. Are arranged in parallel with each other at a predetermined interval, and the peripheral edges of the two side plates 53a and 53b are connected by a peripheral plate 59 so that the air flow from the classification means 2 to the dust collector 4 passes between the side plates 53a and 53b. While forming the separation chamber 51,
A collecting pipe 52 bridging between the side plates 53a and 53b is provided, and an air flow passing through the inside of the separation chamber 51 collides with the collecting pipe 52.

In FIG. 3, magnetic force separating devices 5a and 5b are provided.
An inlet port 54 communicating with the separation chamber 51 is provided at one end forming the right side of the
Is opened, and the inlet 54 is connected to the classification means 2 described above.
Is connected to a pipe communicating with the separation chamber 51. The discharge port 55 formed at the left end in FIG.
The air flow passing through the inside can be introduced into the dust collector 4.

Further, as described above, the lower part of the separation chamber 51 has a hopper shape in which the width is narrowed downward by the side plates 53a and 53b formed in the octagonal shape, and the opening 56 formed at the lower end thereof is shown in FIG. By connecting to the second dust collector 8 for collecting the crushed magnetic abrasive material as shown in (1), the crushed magnetic abrasive material collected by the collecting pipe 52 can be collected.

The windows 53 are provided on the side plates 53a and 53b.
1, 532 can be provided to improve convenience such as maintenance of the magnetic separation devices 5a and 5b. Further, the peripheral plate 59 is provided with slits 591 at predetermined intervals so that outside air can be introduced into the separation chamber 51. It may be configured.

The magnetic force separating device 5 configured as described above.
Collection pipe 52 arranged in (5a, 5b) separation chamber 51
Are arranged in a vertical row as shown in FIG.
A total of 6 rows of the collection tubes 52 are arranged in one.

In this embodiment, the collecting tube 52 having a diameter of 28 mm is vertically arranged with the center-to-center distance thereof being 57 mm.
The book is arranged. Further, the collecting pipe 52 can be attached to the side plate by, for example, bolting through an elongated hole 57 having a lengthwise direction in the left-right direction in FIG.
By sliding the mounting position in the length direction of the, the distance between the collecting tubes 52 in the adjacent rows can be adjusted.

In the embodiment shown in FIG. 3, the collection tube 5
The distance between the center lines of each row of 2 is 45 mm to 50 mm, but in the illustrated embodiment, the distance between the center lines is 45 mm to 50 mm.
It can be changed between 7mm and 64mm.

A magnet is inserted inside the collection tube 52 thus arranged in the separation chamber 51, and the magnetic powder of the magnet is used to collect the crushed magnetic abrasive material in the collection tube 52. Can be attached to the outer circumference of the
For example, by pulling out the magnet inserted in the collection tube 52 from the collection tube 52, or by stopping the energization to the electromagnet when the inserted magnet is, for example, an electromagnet, The crushed magnetic abrasive material collected on the outer periphery falls to the second position through the aforementioned opening 56.
It is configured so that it can be collected in the magnetic abrasive material collecting means including the dust collector 8 and the like.

The magnetic force separating device 5 (5a, 5b)
Inside the separation chamber 51, upstream of the collecting pipe 52, for example, a wire net 58 having a mesh size of about 100 mesh is attached, and the air introduced into the separation chamber 51 is the wire net 58.
May be configured to pass through.

The separating ability of the magnetic abrasive material by the magnetic force separating device 5 (5a, 5b) becomes higher as the flow velocity of the air flow passing through the casing is lower. As a result of experiments, it has been clarified as a result that the separation capacity is improved as the flow velocity of the air flow introduced into the chamber is increased. By providing the wire net 58, the flow velocity of the introduced air flow is accelerated to improve the separation efficiency. You can

Magnetic force separating device 5 constructed as described above
In the configuration example of the low melting point glass recovery device shown in FIG. 1, a and 5b are arranged such that the two magnetic force separating devices 5a and 5b are arranged in parallel to communicate between the classification means 2 and the dust collector 4. This configuration will be described in more detail. The pipe from the classifying means 2 is branched upstream of the two magnetic force separation devices 5a and 5b, is connected to each magnetic force separation device 5a and 5b, and is branched. A switching valve 9 is provided at the branch point so that any one of the pipes can be selectively opened and closed.

The pipes connected to the discharge port 55 of each of the magnetic force separators 5a and 5b are gathered together and connected to the dust collector 4.

Therefore, either one of the magnetic separation devices 5a
(Or 5b) while the crushed magnetic abrasive is being removed, the crushed magnetic abrasive recovered in the other magnetic separation device 5b (or 5a) is recovered and the other magnetic separation device is also recovered. When the magnetic abrasives crushed by 5b (or 5a) are being removed, the magnetic abrasives collected in one of the magnetic separators 5a (or 5b) are collected to interrupt the work. It is efficient because the magnetic abrasive can be removed continuously without any operation.

[Secondary Separation Device] In FIG. 1, 6 is a secondary separation device, and this secondary separation device 6 is the crushed magnetic grinding still contained in the powder collected by the above-mentioned dust collector 4. The material is separated and the recovered powder is preferably 9
The glass has a low melting point of 9.8% or more.

In FIG. 1, the secondary separating device 6 introduces the blast gun 61 for injecting the powder collected in the dust collector 4 together with the compressed air, and the powder injected by the blast gun 61 together with the compressed air. Cyclone 6
2, 63, and the cyclone 62, 63 has a magnet 6 on at least a part of an outer wall made of a non-magnetic material.
It has a structure in which 4, 64 are attached.

In this way, the powder introduced into the cyclones 62, 63 together with the air flow of the compressed air produces a swirling flow along the inner walls of the cyclones 62, 63, and the swirling flows cause the cyclones 62, 63 to have their respective interiors. When the powder is swirled, the crushed magnetic abrasive remaining in the powder is adsorbed by the magnetic force and adheres to the inner walls of the cyclones 62 and 63, and the crushed magnetic abrasive is removed. The cutting powder of the melting point glass is collected in the collecting drum 65.

The powder recovered in the recovery drum 65 as described above can be recovered with the purity of the low melting point glass being 99.8% or more. The high-purity, low-melting-point glass cutting powder collected here is used again for PDP.
It can be used for forming the rib material for partition walls.

After collecting the cutting powder of the low melting point glass in this way, the magnet 64 is removed from the outer periphery of the cyclones 62 and 63, and the air in the cyclones 62 and 63 is sucked by the negative pressure by the second dust collector 8. To discharge. The discharged exhaust gas is sent to the second dust collector 8 and the second dust collector 8
It is collected and discarded together with the magnetic abrasives collected by the magnetic force separating device 5 (5a, 5b).

[Overall Operation of Separating and Collecting Low Melting Point Glass] As an example, a case of forming ribs for partition walls of a PDP by blasting will be described. First, a mask is formed according to the low melting point glass as a partition material and the rib pattern to be formed. The magnetic abrasive is sprayed in the blasting device body 1 onto the glass substrate to which the material is attached.

As the abrasive used for blasting, various magnetic abrasives can be used as long as they can be separated by a magnet, but it is preferable that the amount of carbon is 0 to 0.3% at the time of grinding. In addition to crushing to make dust less likely to occur, it has a hardness lower than that of the substrate glass so that it does not damage the substrate glass, it has a low degree of oxidation that makes it hard to oxidize and reddish when fired. Easy to classify, good processing rate, average particle size 5-50
It is preferably μm, and is selected in consideration of these properties comprehensively.

As an example, heat resistant steel such as SUH material and stainless steel material such as SUS material can be preferably used in view of the above conditions. For example, ferritic heat resistant steel such as SUH21 and precipitation hardening stainless steel can be used. Is SU
S630 or the like can be used, and in particular, the SUH21 with less damage to the substrate can be used more preferably.

When the blasting is performed in this manner, the cutting powder of the low melting point glass and the sprayed magnetic abrasive are pulled by the negative pressure of the dust collector 4 and the conduit is passed through the hopper 10 of the processing chamber. Pass through and enter classification means 2.

In the classifying means 2, the reusable abrasive which has not been crushed is recovered, and the recovered abrasive is then supplied again to the blasting machine main body 1 and used for cutting the workpiece.

The mixed powder composed of the crushed magnetic abrasive and the cutting powder of the low melting point glass as the partition wall material is the above-mentioned classification means 2
Then, it is not recovered but is pulled by the negative pressure of the dust collector 4 and the classification means 2
And is introduced into the magnetic separation device (primary separation device) 5.

At the time of introduction into the magnetic force separation device 5, the switching valve 9 provided at the branch point of the conduit communicating with the inlet of each magnetic force separation device 5a, 5b is provided with one of the magnetic force separation device 5
A and 5b are selected and switched so as to communicate with the classifying means 2.

At this time, the magnetic separation device 5 in which the mixed powder that has passed through the classifying means 2 by the switching of the switching valve 9 is introduced.
A magnet is inserted into the collection pipe 52 in a (or 5b) so that the magnetic abrasive in the mixed powder can be collected, and an opening 56 provided at the bottom is provided, for example. The communication with the second dust collector 8 for collecting the abrasive is blocked by being blocked.

On the other hand, the other separating device 5b (or 5a) which is not in communication with the classifying means 2 is in a state where the abrasive is not attached to the outer periphery of the collecting tube 52 due to the magnet in the collecting tube 52 being pulled out. And the separation chamber 5 through the opening 56.
The air inside 1 is sucked into the second dust collector 8 so that the magnetic abrasive crushed in the second dust collector 8 can be collected.

In this way, when the mixed powder that has passed through the classifying means 2 is introduced into the magnetic force separating device 5 (5a or 5b), the mixed powder flowing from the inlet 54 toward the outlet 55 together with the compressed air. The body collides with the collection tube 52 arranged in the separation chamber 51 and adheres to the outer circumference of the collection tube 52 due to the magnetic force of the magnet inserted in the collection tube 52. Therefore, the air flow exhausted from the exhaust port 55 contains almost no crushed magnetic abrasives, and most of the mixed powder in the air flow is cutting powder of low melting point glass.

In this way, the air flow discharged from the classifying means 2 for a predetermined time determined by the abrasive material collecting ability of the magnetic force separating device 5a (or 5b) is supplied to one magnetic force separating device 5a.
After introducing into a (or 5b), switch the switching valve 9,
The introduction of dust is started to the other magnetic force separation device 5b (or 5a).

When the switching valve 9 is switched, a magnet is inserted into the collecting tube 52 provided in the other magnetic force separating device 5b (or 5a) so that the collecting material can be collected by the collecting tube 52. Is set to the state and the opening 56 provided at the lower end is closed, and the separation chamber 51 formed in the magnetic separator 5b (or 5a) is communicated with the second dust collector 8 for collecting the abrasive. Shut off.

On the other hand, in the magnetic separation device 5a (or 5b), which is cut off from the communication with the classification means 2, the collecting pipe 52 is formed by extracting a magnet from the collecting pipe 52 provided in the separation chamber 51.
The abrasive adhered to the outer periphery of the abrasive is ready to drop, and the separation chamber 51 communicates with the second dust collector 8 for collecting the abrasive through the opening 56, and the suction force generated by the second dust collector 8 causes The air in the separation chamber 51 is sucked.

In this way, when the air in the magnetic force separating device 5a (or 5b) is sucked, the negative pressure causes the abrasive in the collecting pipe 52 to be ground together with the air in the magnetic force separating device 5a (or 5b). The crushed and non-reusable abrasive that has been introduced into the second dust collector 8 for material recovery is recovered here. Then, this operation is repeated until the blast processing is completed.

In this way, by switching the switching valve 9, the powder that has passed through the classifying means 2 can be introduced into any of the magnetic separation devices 5a or 5b without interruption, and the grinding material that is continuously crushed can be separated.・ Able to carry out recovery processing.

In this way, the magnetic force separating device 5 (5a, 5a
The air flow from which the crushed abrasives have been removed by passing through b) is then introduced into the dust collector 4. This dust collector 4
Is a so-called cyclone, and when swirling due to the swirling flow generated along the inner wall of the dust collector 4, powder which is a heavy object in the air is collected in the collection container 41 provided at the lower end of the dust collector 4 and The air from which the powder has been removed is discharged to the outside of the dust collector 4 as exhaust air.

In this way, the powder recovered in the recovery container 41 is almost free of the abrasive material crushed by the magnetic force separating device 5 (5a, 5b) described above, and about 99% thereof.
The cutting powder of high-purity low-melting glass called low-melting glass can be collected.

The dust collected in the dust collector 4 as described above is introduced into the secondary separating device 6 in order to further separate and remove the abrasives which still remain in the dust collector by about 1% if necessary.

As described above, the collection container 41 of the dust collector 4
The powder recovered in step 1 has an average particle size of, for example, 1.5 to 1.6.
Since a fine particle size of about μm is formed, in the present embodiment, when this dust is used in the blast device, it is mixed with the compressed air flow in the blast gun 61 having the same structure and is injected into the cyclones 62, 63. .

The cyclones 62, 63 are made of a non-magnetic material, and by attaching a magnet 64 to the outer wall of the cyclone 62, 63, the magnetic abrasive powder remaining in the air flow introduced can be attached to the inner wall and removed. The crushed abrasive material in the powder injected into the cyclones 62 and 63 is
Due to the magnetic force, it cannot be attached to the inner walls of the cyclones 62 and 63 and fall down, and only the cutting powder of the low melting point glass is collected in the collection drum 65.

The powder collected here is about 9
9.8% is a low melting point glass, and has a high purity that can withstand the use as a rib material of PDP again.

On the other hand, the crushed abrasive material adhered to the inner walls of the cyclones 62 and 63 has the magnet 64 attached to the outer periphery of the cyclones 62 and 63 removed after the cutting powder of the low melting point glass is collected as described above. In this state, the air in the cyclones 62 and 63 is sucked into the second dust collector 8 and collected.

[Performance Test of Magnetic Separation Device] The results of the separation test of the crushed abrasive by the magnetic separation device of the present invention configured as described above are shown below.

1. Blasting conditions Five substrates (810 mm × 1410 mm) coated with a low melting point glass paste on the entire surface of the glass substrate are passed twice inside the blasting device (processing time 29 minutes), and an abrasive (SUS) is sprayed. While producing a mixed powder of low-melting-point glass cutting powder and crushed abrasive, a test is conducted to introduce the low-melting-glass cutting powder and crushed abrasive into the separation device of the present invention to separate the two. It was

2. Test separation device The test separation device used has an outer shape of 1176 in total height.
mm, overall width 330 mm, total length 1685.9 mm, diameter 28 mm
16 collection tubes are provided in the first row, and 17 collection tubes are provided in the second and third rows, respectively, and a total of 50 collection tubes are arranged in the separation device.

The fan motor used in the dust collector was 54 Hz, and the air volume was 50.3 m ³ / min (46.4 m after processing).
³ / min), the average exhaust air velocity is 12.7 m / s (1 after processing 1
1.7 m / s).

Under the above conditions, the conditions such as the distance between the collection tubes of the magnetic separation device, the wind speed of the air flow introduced into the separation device, and the presence or absence of a 100-mesh wire mesh inside the inlet are changed. , The change in the separation capacity of the separation device was measured. The results are shown in Table 1 below.

In the table below, "SUS content" is
It is the SUS content rate in the powder collected by the dust collector 4 in FIG.

[0081]

[Table 1] Relationship between separation ability of magnetic separation device and various conditions * Is nickel abrasive

From the above results, it is confirmed that (1) when the wire mesh is not used, the separation performance is improved by reducing the wind speed of the air flow introduced into the magnetic separation device ( It was confirmed that when a wire mesh was used, the separation capacity was improved with the increase of the wind speed, on the contrary (see separation conditions 4 and 5).

(2) Assuming that the narrower the distance between the collecting tubes, the higher the collecting ability, and that there is a proportional relationship between the distance between the collecting tubes under the separation conditions 2 and 6 and the SUS powder content. If the gap is reduced to 5 mm, S at a wind speed of 10 m / s
It can be expected to reduce the US content to 0.73%.

(3) Further, comparing the separation condition 2 and the separation condition 5 as an example of the presence / absence of a wire mesh, if there is a wire mesh, S
The US content is reduced by 0.2%. Therefore, it can be expected that the content of SUS in the collected dust can be reduced to 0.53% by attaching the wire net under the conditions of the wind speed of 10 m / s and the collection tube interval of 5 mm.

(4) In the above, in the experimental machine of the magnetic separation device, a test with a wind speed of 10 m / s or less was conducted. However, when the separation is performed in an actual machine, the size is increased and the wind speed is 10 m / s. It is difficult to set the wind speed to 10 m / s or less, and work efficiency decreases when the wind speed is set to 10 m / s or less. In, the powder having an SUS content of 1% or less (0.53%) can be recovered by setting the interval between the collecting tubes to 5 mm.

[Abrasive selection test] The basic processing conditions are shown in Table 2 below, and changes in the separation performance of the magnetic separation device were confirmed depending on the type of the abrasive and the processing conditions. The results are shown in Table 3 below.

[0087]

[Table 2] Processing conditions in abrasive selection test The test results under the above basic conditions are shown in Tables 3 to 5 below.

[0088]

[Table 3] Changes in separation capacity due to differences in abrasive materials and processing conditions 1

[0089]

[Table 4] Change in separation ability due to difference in abrasive material type and processing conditions 2

[0090]

[Table 5] Change in separation ability due to difference in abrasive material type and processing conditions 3

From the above results, (1) Under processing condition 1 (using SUS 410L), since the abrasive material is finely crushed, the proportion of the abrasive material mixed in the cutting powder of the low melting point glass increases. Therefore, it becomes difficult to separate the crushed abrasive, and it becomes difficult to collect only the cutting powder of the low melting point glass. In addition, SUS410L shows a high numerical value with an oxidation level of 5, indicating a remarkable red coloration.
It is not suitable for reuse as a partition material for PDP.

(2) Processing condition 2, processing condition 3 and processing condition
In No. 4 (using SUS 410), the crushed abrasive has a very high oxidation degree of 5, which is not suitable for reuse as a rib material for PDP as described above. In addition, the surface roughness of the processed substrate is significantly increased, and the substrate is damaged, so that it is not suitable for use in forming a partition wall of a PDP.

(3) Under the processing conditions 5 and 6 (using SUH21), the mixing ratio of crushed abrasives contained in the dust collected by the dust collector is slightly high, but the degree of oxidation is 3
Is relatively low and the surface roughness of the substrate is almost the same as that of the unprocessed substrate, so that damage to the substrate is small.

(4) Under the processing conditions 7 and 8 (using SUS630), the amount of the abrasive material consumed is large, but the dust generation rate is small, and the crushed abrasive material mixed in the dust collected in the dust collector is used. The mixing ratio of is small. Also, the degree of oxidation is as low as 3, which is a favorable result. However, SUS630 is
It is confirmed that the hardness is higher than that of SUH21 and the surface roughness of the processed substrate is higher than that of SUH21, which damages the substrate.

(5) When urethane rubber is used as the mask material, the amount of dust generated by crushing the magnetic abrasive material is 9
%, And it becomes easy to remove the crushed magnetic abrasive from the cutting powder of the low melting point glass.

(6) Comprehensive evaluation of the above test results shows that the condition of the magnetic abrasive used is preferably that the hardness is lower than that of the substrate from the viewpoint of reducing damage to the glass substrate, and dust due to crushing is also used. It is preferable that the amount of carbon that causes less generation is 0 to 0.3%.

Further, from the viewpoint of preventing reddening of the recovered low melting point glass reused, low oxidation property is preferable, and further, average particle diameter of 5 to 50 μm is relatively easy to recover.

Further, it was confirmed that as a condition for the blasting process, it is preferable to use urethane rubber as a mask material, which is less likely to generate dust due to crushing of the magnetic abrasive.

In the abrasive used in the above test example,
Although the mixing ratio of the crushed abrasive in the mixed powder collected in the dust collector 4 is slightly high (0.32% under the processing condition 5 and 0.21% under the processing condition 6), Since the remaining abrasive can be removed by the above-mentioned secondary separation and the content rate can be reduced to 0.20% or less, it was confirmed that the use of SUH21, which causes less damage to the substrate, is most suitable for the partition wall processing of PDP. .

[0100]

According to the present invention as described above, according to the present invention, it is possible to remove the crushed magnetic abrasive from the cutting powder of the low melting point glass relatively easily and reliably. It was possible to separate and collect the cutting powder of the low melting point glass of high purity.

In particular, the low melting point glass can be separated and recovered with higher purity by performing the blasting process under the predetermined conditions when the low melting point glass is separated and recovered by the method of the present invention. The cutting powder of the low-melting-point glass thus collected is comparable to being used again as a partition material for PDP.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a low melting point glass separating and collecting apparatus of the present invention.

FIG. 2 is a plan view of a magnetic force separator according to the present invention.

FIG. 3 is a sectional front view of a main part of a magnetic force separator according to the present invention.

FIG. 4 is a bottom view of the magnetic force separation device of the present invention.

FIG. 5 is a left side view of the magnetic force separation device of the present invention.

FIG. 6 is a schematic explanatory view of a conventional dust and abrasive removing device.

[Explanation of symbols]

1 Blast device body 10 hoppers (of blasting equipment) 2 classification means 4 dust collector 41 Collection container 5 (5a, 5b) Magnetic force separation device 51 separation room 52 Collection tube 53a, 53b Side plate 531,532 windows 54 entrance 55 outlet 56 openings 57 long hole 58 wire mesh 59 peripheral plate 591 slit 6 Secondary separation device 61 Blast Gun 62,63 cyclone 64 magnet 65 Collection drum 8 Second dust collector 9 switching valve

Claims (22)

[Claims] 1. Reusable from a mixed powder of the magnetic abrasive and cutting powder of low melting glass, which is generated when blasting a substrate formed by applying and drying a low melting glass paste with a magnetic abrasive. The magnetic powder is classified and collected, and the mixed powder after the reusable abrasive is collected is separated by air in a separation chamber in which collection tubes in which magnets are inserted are arranged at predetermined intervals. A magnetic force of a magnetic abrasive, which is introduced together with a flow and passed between the collecting tubes, and the crushed magnetic abrasive mixed in the mixed powder is attached to the collecting tube and collected. Separation method. 2. The flow velocity of the air flow introduced into the separation chamber together with the mixed powder is 3 m to 30 m / sec, preferably 8 m / sec.
The magnetic separation method for magnetic abrasives according to claim 1, wherein the magnetic abrasives have a length of -12 m. 3. After stopping the introduction of the mixed powder into the separation chamber, the magnet in the collection tube is removed, and
The magnetic separation method for magnetic abrasives according to claim 1 or 2, wherein air in the separation chamber is sucked to recover the crushed magnetic abrasives collected in the separation chamber. 4. The magnet is an electromagnet, and after the introduction of the mixed powder into the separation chamber is stopped, the energization of the magnet in the collection tube is stopped and the air in the separation chamber is sucked to perform the separation. The magnetic separation method for magnetic abrasives according to claim 1 or 2, wherein the crushed magnetic abrasives collected in the room are recovered. 5. At least two separation chambers are arranged in parallel, and when the mixed powder is introduced into one of the separation chambers, the introduction of the mixed powder into another separation chamber is stopped. In addition, the crushed magnetic abrasive collected in the separation chamber is discharged to the outside of the separation chamber to be collected, and when the mixed powder is introduced into the other separation chamber, the mixture for the one separation chamber is mixed. 5. The introduction of the powder is stopped, and the crushed magnetic abrasive collected in the one separation chamber is discharged to the outside of the separation chamber and collected. Magnetic separation method for magnetic abrasives. 6. The magnetic force of the magnetic abrasive according to claim 1, wherein the blasting is performed by jetting a magnetic abrasive at a processing pressure of 0.01 to 0.3 Mpa. Separation method. 7. A classifying means for introducing a mixed powder of a magnetic abrasive and a cutting powder of low melting point glass generated in a blasting device, and classifying and collecting a reusable magnetic abrasive from the mixed powder. By the above, the mixed powder after the reusable magnetic abrasive is removed is treated, and the mixed powder introduced together with the airflow through the introduction port communicated with the classification means and the introduction port. A separation chamber through which the body passes and an outlet for discharging the mixed powder that has passed through the separation chamber to the outside of the separation chamber together with the airflow, and a plurality of trapped magnets arranged at predetermined intervals in the separation chamber. A magnetic separator for magnetic abrasives, characterized by having a collecting tube. 8. The upstream side of the position where the collecting pipe is arranged, the separation chamber is partitioned in a direction orthogonal to the flow direction of the air flow by 5 to 200 mesh, preferably 50 to 150 mesh, and more preferably 70 to 130. A magnetic force separating method for a magnetic abrasive material according to claim 1, or a magnetic force separating apparatus for a magnetic abrasive material according to claim 7, characterized by comprising a wire mesh. 9. The arrangement interval of the collecting tubes is 3 mm to 10 mm.
9. The magnetic force separating device for a magnetic abrasive according to claim 8, wherein. 10. The magnetic separator for magnetic abrasives according to claim 8, wherein the magnet can be pulled out from the collecting tube. 11. The magnetic separator for magnetic abrasives according to claim 7, wherein the magnet is an electromagnet. 12. Reusable from a mixed powder of the magnetic abrasive and cutting powder of the low melting point glass, which is generated when the substrate formed by applying and drying the low melting point glass paste with the magnetic abrasive is blasted. A step of classifying and collecting different magnetic abrasives, a primary separation step of separating magnetically the crushed magnetic abrasives mixed in the mixed powder after collecting the reusable abrasives by the step, By the primary separation step, the crushed magnetic abrasive that is still mixed in the mixed powder from which the crushed magnetic abrasive has been removed,
A high-purity recovery method for low-melting-point glass, further comprising a secondary separation step of separating by magnetic force, and recovering the cutting powder of the low-melting-point glass from which the crushed magnetic abrasive has been removed. 13. The mixed powder that has undergone the primary separation step is introduced into a dust collector and collected, and the mixed powder collected by the dust collector is subjected to the secondary separation step. A high-purity recovery method of the low melting point glass described. 14. The high-purity recovery of low-melting-point glass according to claim 12 or 13, wherein the primary separation step is performed by the magnetic separation method for magnetic abrasives according to any one of claims 1 to 6. Method. 15. In the secondary separation step, the mixed powder that has been subjected to the primary separation step is jetted together with an air flow into a cyclone made of a non-magnetic material having a magnet attached to the outer wall and crushed to the inner wall of the cyclone. The high-purity recovery method of low melting point glass according to claim 13 or 14, which is carried out by attaching a magnetic abrasive. 16. A classifying means for recovering a reusable magnetic abrasive from a mixed powder composed of a magnetic abrasive and a cutting powder of low melting point glass generated in a blasting device, and a magnetic material reusable by the classifying means. A primary separating device that introduces the mixed powder after the abrasive is removed and separates the crushed magnetic abrasive in the mixed powder by magnetic force, and removes the crushed magnetic abrasive by the primary separator. A high-purity recovery device for low-melting-point glass, comprising a secondary separation device for separating, by magnetic force, the crushed magnetic abrasive that is still mixed in the mixed powder. 17. A dust collector for introducing the mixed powder from which the crushed magnetic abrasive has been removed by the primary separation device together with an air flow to recover the mixed powder from the air flow. The high-purity recovery device for low-melting glass according to claim 16. 18. The primary separation device according to any one of claims 7 to 11.
18. The high purity recovery apparatus for low melting point glass according to claim 16 or 17, which is the magnetic force separating apparatus for magnetic abrasives according to any one of claims 1 to 18. 19. The primary separation device is composed of a plurality of magnetic force separation devices arranged between the classifying means and the dust collector, and an outlet of the classifying device is branched to an inlet port of the plurality of magnetic force separation devices. A switching valve is provided which communicates with each other and which is located upstream of the magnetic force separation device and can selectively communicate the discharge port of the classification means with any one of the plurality of magnetic force separation devices. The high-purity recovery device for low-melting glass according to claim 18. 20. A blast gun, wherein said secondary separation device mixes and injects the mixed powder that has passed through said primary separation device with an air flow; and a cutting powder of low melting point glass injected together with the air flow by said blast gun. 17. A high-purity recovery apparatus for low-melting-point glass according to claim 16, characterized in that it comprises a cyclone made of a non-magnetic material into which is introduced, and a magnet arranged around the cyclone. 21. The magnetic abrasive is a ferritic heat resistant steel or a precipitation hardening stainless steel, preferably SUS63.
0, and more preferably SUH21, The method for separating magnetic force of a magnetic abrasive according to claim 1, wherein
A magnetic abrasive for use in the magnetic separation device for a magnetic abrasive according to claim 12, the method for recovering high purity of low melting glass according to claim 12, or the device for recovering high purity of low melting glass according to claim 16. 22. The magnetic abrasive has a lower hardness and a lower oxidative property than a substrate, a carbon content of 0 to 0.3%, and an average particle diameter of 5 to 5.
A magnetic abrasive material having a thickness of 50 μm.
A method for magnetically separating magnetic abrasives according to claim 7, a magnetic separator for magnetically abrasives according to claim 7, a high purity recovery method for low melting glass according to claim 12, or a high purity recovery for low melting glass according to claim 16. Magnetic abrasive used in the equipment.