JP2000005509A - Powder material recovery device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To recover a powder material contained in wastewater used for chemical treatment by a simple mechanism to improve the recovery efficiency. SOLUTION: The tank is provided with a tank 11 for charging drainage to settle the powder material, a pump for discharging water from the tank 11 through a pipe, and a filter arranged in the pipe. Then, the tank 11 is divided into a plurality of small rooms by the partition wall 22 having the lower opening a at the lower end and the partition wall 23 having the upper opening b above the lower end. Tank 1
The powder material can be effectively removed from the waste water by successively settling of the powder material while the waste water introduced into 1 passes through each small room.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for recovering powder material contained in wastewater used for chemical treatment.

[0002]

2. Description of the Related Art Conventionally, this type of recovery apparatus has been used for recovering inorganic or organic powder from wastewater used for chemical treatment in the manufacturing process of various products such as electronic equipment. . For example, regarding a manufacturing process of a plasma display panel (hereinafter, referred to as a PDP), when electrodes, ribs, phosphor screens, and the like are formed by a photolithography method, silver powder contained in wastewater of a developing process,
A device that collects glass powder, phosphor powder, and the like is used, and as the recovery device, a device that collects by filtering through a filter is generally used. Here, the manufacturing process of the PDP will be described.

Generally, a PDP has a structure in which a pair of regularly arranged electrodes are provided on two opposing glass substrates, and a gas mainly composed of Ne, Xe, or the like is sealed between the electrodes. Then, by applying a voltage between these electrodes and generating a discharge in a minute cell around the electrodes,
Each cell emits light to perform display. In order to display information, regularly arranged cells are selectively caused to emit light. There are two types of PDPs, a direct current type (DC type) in which the electrodes are exposed to the discharge space, and an alternating current type (AC type) in which the electrodes are covered with an insulating layer. And a refresh driving method and a memory driving method.

FIG. 1 shows a configuration example of an AC type PDP. This figure shows the front plate and the back plate separated from each other. As shown in the figure, two glass substrates 1 and 2 are arranged in parallel and opposed to each other, and both become the back plate. The ribs 3 provided on the glass substrate 2 in parallel with each other are held at regular intervals. On the back side of the glass substrate 1 serving as a front plate, composite electrodes composed of a sustain electrode 4 which is a transparent electrode and a bus electrode 5 which is a metal electrode are formed in parallel with each other, and a dielectric layer 6 is covered thereover. The protective layer 7 (MgO layer) is further formed thereon. On the front side of the glass substrate 2 serving as the back plate, address electrodes 8 are formed between the ribs 3 so as to be orthogonal to the composite electrodes and are formed in parallel with each other. Are formed, and a phosphor 10 is provided so as to cover the wall surface of the rib 3 and the cell bottom surface. The AC type PDP is of a surface discharge type, and has a structure in which an AC voltage is applied between composite electrodes on a front panel to discharge by an electric field leaking into a space. In this case, since the alternating current is applied, the direction of the electric field changes according to the frequency. Then, the phosphor 10 emits light by the ultraviolet light generated by the discharge, so that an observer can visually recognize the light transmitted through the front plate.

In the back plate of the PDP as described above, an address electrode 8 is formed on a glass substrate 2, a dielectric layer 9 is formed so as to cover it, if necessary, and a rib 3 is formed. It is manufactured by providing a phosphor screen made of the phosphor 10 between the ribs 3. As a method of forming the electrode 8, a method of forming a film of an electrode material on the substrate 2 by a vacuum evaporation method, a sputtering method, a plating method, a thick film method, and the like, and patterning the film by a photolithography method, and a method of forming a thick film paste A patterning method using a screen printing method used is known. The dielectric layer 9 is formed by screen printing or the like, and the ribs 3 are formed by overprinting by screen printing, sandblasting, photolithography, or the like. Further, the phosphor screen is formed by a method of selectively filling phosphor paste of three colors of red (R), green (G), and blue (B) between the ribs 3 by screen printing, or a high-definition type. In Japanese Patent Application Laid-Open No. H11-157, a phosphor screen is formed between ribs by a photolithography method using a phosphor paste.

[0006]

Among the above-mentioned methods for forming a phosphor screen of a PDP, in the method of forming a phosphor screen by photolithography, a photosensitive phosphor paste is coated over a rib with a solid and dried. After repeating a process and a process of performing exposure and development to leave a phosphor paste in a predetermined cell space by a required number of colors, a phosphor screen is completed through a firing process in an oven. in this way,
When forming a phosphor screen by photolithography,
Exposure and development are repeated for the phosphor paste for each color. This development step is performed by spray development using water. However, since a large amount of phosphor powder is contained in the wastewater, it is necessary to collect and reuse it. Currently, wastewater from the developing device is filtered through a filter to collect the phosphor powder, but the work of removing the phosphor attached to the filter is difficult and inefficient, and the life of the filter is short. There is.

Not only in the case of such a phosphor screen formation,
When forming electrodes and ribs by photolithography,
Furthermore, not only in the PDP manufacturing process, but also in the case where powder material is contained in wastewater used for other chemical treatments, because a filtration-type recovery device using a filter is used. There is a similar problem.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a powder material collecting apparatus which has a simple mechanism and high collection efficiency.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is an apparatus for recovering powder material contained in waste water. Tank, a pump for discharging water from the tank via a pipeline, and a filter disposed in the pipeline, wherein the tank is formed by a partition wall having a lower opening at a lower end and a lower end. It is characterized by being divided into a plurality of small rooms by a partition wall having an upper opening above.

It is preferable to provide a drain for draining water at the bottom of the small room. Further, it is preferable to provide a pan that penetrates through the opening of the partition wall having an opening at the lower end and covers the entire bottom of the small room on both sides, and allows the pan to be put in and out of the tank side wall. Further, it is preferable to provide a discharge valve that is automatically adjusted so that the water surface comes to a position higher than the upper opening.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 is a schematic diagram showing an example of a recovery apparatus according to the present invention. In FIG. 12 and the discharge pipe 13 are connected. The discharge pipe 13 is connected to a pump 15 via a discharge valve 14, and water discharged from the pump 15 is discharged through an intermediate pipe 16, a filtration unit F, and a discharge pipe 17. Then, the intermediate pipe 1 from the pump 15 to the filtration unit F
6 is provided with a flow meter 18 and a pressure gauge 19.

As shown in FIG. 3, a cross section of the tank 11 is composed of a tank body 20 and a lid 21 covering the tank body 20. The aforementioned supply pipe 12 and discharge pipe 13 are connected to the outlets, respectively. Further, inside the tank body 20, partition walls 22 having a lower opening a at the lower end and partition walls 23 having an upper opening b above the lower end are provided alternately. , 23, the interior of the tank 20 is divided into a plurality of small rooms, and adjacent small rooms are communicated with each other by a lower opening a and an upper opening b.

For example, when waste water from a developing device used for forming a phosphor screen of a PDP by photolithography is introduced into the tank 11 through the supply pipe 12, the waste water flows into the lower opening a of the partition wall 22. And is sequentially discharged from the discharge pipe 13 through the upper opening b of the partition wall 23. In this case, the discharge valve 14 is opened and the pump 15 is operated, but the discharge valve 14 is automatically adjusted so that the water surface W comes to a position higher than the upper opening b as shown in FIG. I have. Then, during the movement of the water, the phosphor powder in the drainage sequentially sinks to the bottom of each small room due to its specific gravity, and the water discharged from the discharge pipe 13 does not contain the phosphor powder. Here, if the water surface is at the height of the lower end position of the upper opening b, when the water flows into the next room, it may agitate the water accumulated in the next room, as described above. When the water surface W is at a position higher than the upper opening b,
The water flowing into the next room is less likely to agitate the already accumulated water.

When cleaning the tank 11, it is necessary to remove water from each of the small rooms. To simplify the removal of water, it is preferable to provide a drain 24 for draining water at the bottom of the small room. In this case, only one drain needs to be provided in two adjacent small rooms connected by the lower opening a.
In order to easily remove the phosphor powder settled on the bottom of the small room, as shown in FIG. It is preferable to provide a pan 25 that covers the entire bottom of the small room, and that the pan 25 can be taken in and out like a drawer from the side wall of the tank. The bread 25 is set in all the small rooms. This makes the bread with the phosphor powder 2
By pulling out 5, the phosphor powder can be recovered.

In the water from which the phosphor powder has been removed in the tank 11 as described above, there may be a case where the phosphor powder is small but small. Therefore, as described above, the tank 1
The water from 1 is preferably discharged through a filtration section F. Referring back to FIG. 2, the filtration unit F is located between the intermediate line 16 and the discharge line 17, and two lines in which an injection valve 27 and a discharge valve 28 are inserted before and after the two filters 26 are arranged in parallel. It is constituted by providing. That is, by setting the injection valve 27 and the discharge valve 28 in each line to either the open state or the closed state, one of the lines is used, and the filter 2 is used for the unused line.
6 is to be cleaned or replaced. The time of replacement of the filter 26 can be known from the flow meter 18 and the pressure gauge 19 inserted in the intermediate pipe 16 extending from the pump 15 to the filtration section F.

[0016]

As described above, according to the powder material recovery apparatus of the present invention, the inside of the tank is divided into small rooms by the partition wall having the lower opening and the partition wall having the upper opening. Therefore, the powder material sequentially sinks while the waste water of the developing device charged into the tank passes through each small room, so that the powder material can be effectively removed from the development waste water.

Further, by providing a pan that covers the entire bottom of the two small rooms connected by the lower opening and allowing the pan to be taken in and out of the tank side wall, the settled powder material can be easily collected. Can be.

Further, by providing a discharge valve which is automatically adjusted so that the water surface comes to a position higher than the upper opening, the water flowing into the adjacent room is less likely to agitate the already accumulated water, As a result, the sedimentation action of the powder material increases.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a plasma display panel in which a front plate and a back plate are separated from each other.

FIG. 2 is a schematic configuration diagram showing an example of a powder material recovery device according to the present invention.

FIG. 3 is a sectional view of a tank in the recovery device of FIG. 1;

FIG. 4 is a cross-sectional view for explaining an example in which a pan is installed in a tank.

[Explanation of symbols]

 1, 2 glass substrate 3 rib 4 sustain electrode 5 bus electrode 6 dielectric tank 7 protective tank 8 address electrode 9 dielectric tank 10 phosphor 11 tank 12 supply pipe 13 discharge pipe 14 discharge valve 15 pump 16 intermediate pipe 17 discharge pipe Path 18 Current meter 19 Pressure gauge 20 Tank body 21 Lid 22, 23 Partition wall 24 Drain 25 Pan 26 Filter 27 Injection valve 28 Discharge valve F Filtration unit a Lower opening b Upper opening

Claims (4)

[Claims] An apparatus for recovering powdery material contained in wastewater, comprising a tank for charging wastewater to settle the powdery material, and discharging water from the tank via a pipe. Pump, and a filter disposed in the pipeline thereof, wherein the tank is divided into a plurality of small chambers by a partition wall having a lower opening at a lower end and a partition wall having an upper opening above the lower end. An apparatus for recovering a powder material, comprising: 2. The powder material collecting device according to claim 1, wherein a drain for draining water is provided at the bottom of the small room. 3. A pan which penetrates through the opening of the partition wall having the lower opening and covers the entire bottom of the small room on both sides, wherein the pan can be taken in and out of the tank side wall. 2. The apparatus for recovering a powder material according to claim 1. 4. The powder material collecting apparatus according to claim 1, further comprising a discharge valve which is automatically adjusted so that the water surface comes to a position higher than the upper opening.