JP2001340885A - Water treatment device for water washing paint booth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the treatment efficiency of water for a booth in a treating tank by microorganism, thereby surely decomposing paint components in a predetermined time, and to reduce the number of the treating tanks required for cleaning paint waste liquor, thereby decreasing the cost of equipment and the running cost. SOLUTION: In a treating tank (2) for temporarily storing water for a water washing paint booth in which paint mist is caught, a forced convection generating device (3) is installed for vertically circulating the water for the booth. A shredding device (4) for micro-granulating the paint components contained in the water for the booth, and a reactor (5) carrying microorganisms for decomposing the paint components contained in the water for the booth are installed so as to face the flow of the circulation flow (F) or installed in the flow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-washing-type paint booth water treatment apparatus for catching paint mist oversprayed in a paint booth and purifying booth water containing paint components.

[0002]

2. Description of the Related Art In a water-washable paint booth, booth water, also called circulating water, is used to catch paint mist that has been oversprayed. The booth water discharged from the water-washing paint booth contains paint resin, organic solvents, pigments, and other additives that cause odors. In addition, because there is too much water to treat as industrial waste as it is, conventionally, paint components and water were separated,
The paint components are discarded as industrial waste, and the water is reused as the booth water in the flush-type painting booth again.

[0003] Recently, there has been a call for reducing the amount of waste for the purpose of preserving the global environment, and attempts have been made in the coating industry to reduce the amount of industrial waste to meet this demand. It has been proposed to decompose paint components contained in booth water to reduce the amount.

According to this, as shown in FIG. 3, a container 42 is placed in a treatment tank 41 for introducing booth water that has captured paint mist oversprayed in a water-washing type painting booth 40.
In this container 42, Acromobacter species, Aciinobacter species, Erowumonas species, Shademonas species, which prefer to decompose oils and fats, solvents, emulsifiers, paint resins, pigments, dyes contained in booth water, Bacterial species,
A reactor 43 supporting microorganisms such as a mycobacterium species, a flavobacterium species, a methanocarcass species, and a microcarcass species is housed in advance. Then, while maintaining the temperature in the treatment tank 41 at about 40 ° C., at the same time, air is supplied from the air supply pipe 47 arranged on the bottom of the tank to activate the microorganisms, and the paint component of the booth water is decomposed by the microorganisms. The paint components that have not been completely decomposed are aggregated, collected by the filtration device 44, and discarded.

[0005]

However, when it is intended to decompose paint components by microorganisms, it takes a long time to decompose the paint components, and when a large amount of booth water is to be treated, the water is discharged to the filtration device 44 without being completely treated. There was a problem of not getting.

In particular, in an automobile painting factory where a large amount of booth water is discharged, it is necessary to provide a large number of processing tanks 41 in parallel or in multiple stages, and a large number of processing tanks must be provided. However, there is a problem that equipment costs and running costs increase due to the necessity.

[0007] Even in this case, in reality, the paint component of the booth water is discharged without being decomposed in the treatment tank 41 and collected by the filter 45 of the filtering device 44 or the size of the mesh of the filter 45. Depending on the filter 4
There was also a problem that the vehicle passed through No. 5. For this reason,
In a conventional apparatus, a reactor 43 supporting microorganisms is placed in a filtrate tank 46 for storing a filtrate of a filtration device 44, and the filtrate is decomposed by microorganisms. Since it was not decomposed, the cause of the odor could not be eliminated.

Accordingly, the present invention improves the treatment efficiency of the booth water in the treatment tank by microorganisms so that the paint components can be surely decomposed within a predetermined time, and the treatment tank necessary for purifying the waste liquid. It is a technical task to reduce the number of equipment and the equipment cost and running cost.

[0009]

According to a first aspect of the present invention, there is provided a water treatment apparatus for a water-washing type painting booth.
A forced convection forming device that circulates the booth water up and down is disposed in a treatment tank that temporarily stores the water for the wash-type painting booth that has captured the paint mist, facing the flow of the circulating flow or in the flow. In addition, a crushing device for atomizing paint components contained in the booth water and a reactor carrying microorganisms that decompose the paint components contained in the booth water are provided.

According to a second aspect of the present invention, the crushing device comprises an ultrasonic oscillator, and the ultrasonic oscillating surface is disposed facing or facing the flow of the circulating flow. According to a third aspect of the present invention, the crushing device comprises a rotary cutter blade, and the rotation speed is selected to be 1000 rpm or more. According to a fourth aspect of the present invention, the reactor is formed in a film shape and arranged along the flow of the circulating flow. The invention according to claim 5 is provided with a centrifuge for solid-liquid separation of the booth water treated in the treatment tank. In the invention of claim 6, the treatment tank is formed by partitioning the cake pond.

According to the first aspect of the invention, the booth water stored in the processing tank is circulated up and down by the forced convection forming device, and the paint component and the water circulate in the processing tank. Facing or in the flow of the circulating flow, a crushing device such as a rotary cutter blade or an ultrasonic oscillator and a reactor supporting microorganisms that decompose paint components are disposed, so that the booth water is provided. Is finely atomized, and the paint component having a reduced particle size circulates in the treatment tank together with water, and the solid or liquid paint component comes into contact with the reactor and is decomposed by microorganisms. At this time, since the paint component is atomized by the crushing device, the surface area per unit volume is extremely large, and therefore, it is decomposed by microorganisms in an extremely short time.

Further, if an ultrasonic oscillator is arranged as a crushing device such that its oscillation surface faces or opposes the flow of the circulating flow, the coating composition becomes coarse. Even if supplied in a state, the coarsened paint components are reliably atomized while circulating, so that highly viscous paint components are less likely to adhere to the reactor, and the processing efficiency is further improved. The same applies to a case where a rotary cutter blade is used as a crushing device and the crushing device is rotated at a high speed of 1000 to 3000 rpm.

Further, if the reactor is formed in a film form and provided along the flow of the booth water, the flow does not hinder the flow and the contact area with the booth water is large. Processing efficiency is further improved.

[0014] The paint components remaining in the booth water treated with microorganisms in the treatment tank in this way are inorganic pigments and their excretions that cannot be decomposed by microorganisms, and these are also pulverized by a crusher. Therefore, if solid-liquid separation is attempted with a filtration device, the filter is likely to be clogged, requiring frequent replacement.At that time, the used filter must be disposed of as industrial waste, and Goes against weight loss. Therefore, in the invention of claim 5, fine paint components and water contained in the booth water treated in the treatment tank are separated into solid and liquid by a centrifugal separator, so that filter clogging and disposal of used filters are performed. Does not cause problems.

Further, if the treatment tank is formed by partitioning the cake pond, it is not necessary to secure a space for installing the treatment tank.

[0016]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is an explanatory view showing an example of a water treatment apparatus for a water-washing type painting booth according to the present invention, and FIG. 2 is an explanatory view showing another embodiment.

The water treatment apparatus 1 for a water-washing painting booth shown in FIG. 1 comprises a treatment tank 2 for temporarily storing booth water and a centrifugal separator 18 for solid-liquid separation of the booth water treated in the treatment tank 2. Become.

In the treatment tank 2, a forced convection forming device 3 for circulating the booth water up and down is disposed, and the paint component contained in the booth water is placed facing or in the flow of the circulating flow. A crushing device 4 for atomizing and a reactor 5 supporting microorganisms for decomposing paint components contained in booth water are provided.

The treatment tank 2 is provided with a waste water from a booth water storage tank 6a formed at the bottom of the exhaust chamber of the washing type painting booth 6 and a pulp pond (not shown) for storing booth water drained from the washing type painting booth 6. This is for batch processing of booth water fed through a pump 8 through a pipe 7, wherein a tank bottom 2a is formed in a hemispherical shape, and a top surface 2b is formed in an open cylindrical tank 9. ing.

The forced convection forming device 3 comprises a cylindrical guide pipe 10 arranged at the center of the tank 9 and a liquid feeder 11 for pushing out the booth water in the guide pipe 10 downward. The upper and lower ends of the guide pipe 10 are open, and are provided at a depth that opens in the booth water stored in the processing tank 2.

The propeller 1 has a rotary shaft 13 of a motor 12 arranged outside the tank 9 introduced into the guide pipe 10 and pushing booth water downward at the end thereof.
4 is attached. By rotating the propeller 14, in the treatment tank 2, the booth water flows downward from the liquid surface side through the guide pipe 10, is inverted at the tank bottom 2 a, passes through the outside of the guide pipe 10, and rises upward. A circulating flow F is formed, which is forcedly convected so as to head and circulates up and down.

The booth water flowing downward from the opening at the lower end of the guide pipe 10 is diffused radially along the hemispherical surface of the tank bottom 2a, and then inverted upward. Thus, a substantially conical projection 15 is provided. In addition, if the directivity of the flow formed by the propeller 14 is strong, the circulation flow F can be formed by forcibly convection the booth water up and down without the guide pipe 10. Further, the circulating flow F does not always flow linearly in the processing tank 2 and may be circulated as a vortex, but in any case, circulates vertically in the processing tank 2.

The crushing device 4 is mounted around the tank 9 near the tank bottom 2a so as to be located immediately before the reactor 5 with respect to the flowing direction of the circulation flow F. In this example, an ultrasonic oscillator is used as the crushing device 4, and the ultrasonic oscillation surface 4a is disposed facing the flow of the circulating flow F of the booth water.

In addition, reactors 5 carrying microorganisms
Is formed in a cylindrical film shape with a nonwoven fabric or the like, and is provided concentrically with the guide pipe 10 so as to follow the flow of the booth water. Further, below the reactors 5, an air supply pipe 16 for aerating and activating microorganisms is arranged in a ring shape, and is connected to an air pump 17 arranged outside the tank 9.

A liquid feed pipe 19 for feeding the treated booth water to the centrifugal separator 18 is connected to the tank bottom 2a of the processing tank 2, and is continuously supplied by the pump 20 until the booth water runs out. You. The centrifugal separator 18 is provided with the liquid sending pipe 19.
The booth water sent through the system is solid-liquid separated into paint components and water, such as inorganic pigments and microbial excretions that are not decomposed by microorganisms.The paint components are disposed of as industrial waste, and the water It is circulated and supplied to the washing type painting booth 6.

The above is one configuration example of the present invention, and its operation will be described below. First, the booth water, in which the paint mist is captured by the water-washing type painting booth 6, is temporarily stored in the booth water storage tank 6a, and then sent to the processing tank 2 by the pump 8 through the liquid feed pipe 7.

When the required amount of booth water has been stored in the treatment tank 2, air is supplied from the air supply pipe 16 to aerate the microorganisms carried in the reactors 5 so as not to be deprived of oxygen, thereby forming forced convection. The apparatus 3 is started to rotate the propeller 14 and the crushing apparatus 4 such as an ultrasonic oscillator is started.

As a result, the booth water flows downward from the liquid surface side through the guide pipe 10 to the tank bottom 2a.
And is forcedly convected so as to pass upward through the outside of the guide pipe 10, thereby forming a circulating flow F circulating up and down. Further, since the crushing device 4 is arranged facing the circulating flow F, all the booth water passes through the front of the crushing device 4 and is affected by the ultrasonic wave, so that the paint component contained in the booth water is finely divided. Crushed.

At this time, the crushing device 4 is mounted around the tank 9 near the tank bottom 2a so as to be located immediately before the reactor 5 with respect to the flowing direction of the circulation flow F.
Even if the paint component is coarsened and supplied in a highly viscous state, the paint component is crushed before reaching the reactor 5 and hardly adheres to the reactor, and is further finely atomized during circulation.

Since the circulating flow F is formed, of the paint components contained in the booth water, those having a low specific gravity floating on the liquid surface, those having a high specific gravity sinking in the liquid, and those in the liquid surface or in the liquid. Without stagnation, circulates up and down on the circulating flow F, flows between the membrane-like reactors 5 and flows, and the paint component is decomposed by microorganisms carried on the reactors 5. .

Among the paint components, the liquid components are decomposed in a short time due to the small aggregation of molecules, and the paint components are also finely crushed by the crushing device 4 to reduce the particle size. Is extremely large, so that the amount remaining without being completely decomposed is small, and it is decomposed surely in a short time. When the circulating flow F is formed, bubbles formed on the liquid surface ride on the circulating flow F and are forcibly submerged in the liquid, and are destroyed by the liquid pressure.

As described above, the booth water is stored in the treatment tank 2 to form the circulating flow F, and the convection is forcibly convected for a predetermined time, whereby the paint components contained therein can be decomposed.
Inorganic pigments and microorganism excretions that could not be decomposed by microorganisms remain as paint components in the treated booth water, and these paint components are also finely crushed by the crushing device 4.

The booth water, which has been decomposed by microorganisms, is supplied by a pump 19 at a predetermined flow rate into a liquid sending pipe 20.
Are sequentially fed to the centrifugal separator 18 to separate the paint components and water into solid and liquid. When the inside of the processing tank 2 is empty, the booth water storage tank 6a of the water-washing type coating booth 6 is returned again.
To supply the booth water to the treatment tank 2 and treat the booth water in the same procedure as described above.

When the booth water is subjected to solid-liquid separation by a filtration device, the filter is likely to be clogged, requiring frequent replacement. At that time, the used filter must be disposed of as industrial waste. Must be
It goes against the waste reduction, but the use of the centrifuge 18 does not cause such a problem.

FIG. 3 is an explanatory view showing still another embodiment of the present invention. The parts common to FIG. 1 are denoted by the same reference numerals, and the detailed description is omitted. In the water treatment device 31 for a flush-type painting booth of this example, a treatment tank 32 for treating microorganisms in the booth water is incorporated in a cake pond 33 for storing booth water discharged from the flush-type painting booth 6.

The lees pond 33 is partitioned by a partition plate 34 into a storage tank 35 and a processing tank 32, and the booth water flowing into the processing tank 32 from the storage tank 35 is treated with microorganisms. The partition plate 34 is a movable weir, and by opening it, the booth water can flow into the treatment tank 32 from the storage tank 35.

In the case of this example, the partition plate 34 is opened, the booth water flows into the processing tank 2 until the predetermined liquid level is reached, and the partition plate 34 is closed. Next, as described above, by rotating the propeller 14 of the forced convection forming device 3, the booth water is forcibly convected to form a circulating flow F circulating up and down, and the paint components are atomized by the crushing device 4. At the same time, the paint components in the booth water are decomposed by the microorganisms carried in the reactor 5, and when the treatment is completed, they are sent to the centrifugal separator 18 to perform solid-liquid separation.

The partition plate 34 is slightly opened to allow the booth water to always flow from the storage tank 35 and discharge the same amount as the inflow so as to keep the liquid level in the processing tank 32 constant. Alternatively, the processing may be performed continuously.

The case where the processing tanks 2 and 32 are provided independently and the case where the processing tanks 2 and 32 are installed in the cake pond 33 have been described.
Not limited to this, the treatment tank is formed by partitioning the storage tank 6a formed in the lower part of the exhaust chamber of the washing type painting booth 6, or the booth water sucked into the exhaust chamber from the coating chamber via the venturi section 6b is directly supplied. For example, a treatment tank may be formed immediately below the venturi section 6b so as to flow into the coating booth 6.

Further, the crushing device 4 is not limited to an ultrasonic oscillator, and a rotary cutter blade may be used. In this case, if it is less than 1000 rpm, the paint component cannot be sufficiently atomized. If it exceeds 3000 rpm, cavitation occurs, and the rotary cutter idles and the atomization efficiency decreases, so that the rotation speed is about 1000 to 3000 rpm. It is desirable to rotate with.

[0041]

As described above, according to the present invention, the paint component contained in the paint waste liquid is finely crushed and atomized, and the individual particles become extremely light. Flow through the reactor carrying the microorganisms, and because the surface area per unit volume is increased by atomization, the paint components are surely decomposed by the microorganisms in a short time. It is possible to reduce the number of treatment tanks required for purifying booth water and reduce equipment costs and running costs. It has a very excellent effect of being able to produce

In particular, if the crushing device is disposed immediately before the reactor with respect to the flow direction of the circulating flow, even if the paint component is supplied to the treatment tank in a coarse state, the coarse paint component is supplied. Is crushed by the crushing device before reaching the reactor, so that highly viscous paint components are less likely to adhere to the reactor, and the processing efficiency is further improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a water treatment apparatus for a water-washing type painting booth according to the present invention.

FIG. 2 is an explanatory diagram showing another embodiment.

FIG. 3 is an explanatory view showing a conventional device.

[Explanation of symbols]

 1, 31 ... water treatment equipment for a water-washing painting booth 2, 32 ... treatment tank 3 ... forced convection forming device 4 ... crushing device 5 ... reactor 6 ... water-washing painting booth F ... …… Circulation flow 10 ……… Guide pipe 18 ……… Centrifuge 33 ……… Kasuike

Continuing from the front page (72) Inventor Hidetoshi Omori 1-9-9 Kakimotocho, Toyota City, Aichi Prefecture Inside Trinity Industry Co., Ltd. (72) Inventor Hitoshi Yano 1-9-9 Kakimotocho Toyota City, Aichi Prefecture Trinity F term in Industrial Co., Ltd. (reference) 4D003 AA01 AB02 AB05 AB07 BA01 BA02 CA01 CA04 CA10 DA01 DA08 DA11 DA15 DA19 DA23 DA30 EA07 EA18 FA06 4D073 AA01 BB06 DC21

Claims (6)

[Claims] A forced convection forming device (3) for circulating the booth water up and down is disposed in a treatment tank (2, 32) for temporarily storing water for a washing type coating booth that has captured the paint mist, Facing or in the flow of the circulating flow (F), a crushing device (4) for atomizing the paint component contained in the booth water and a microorganism for decomposing the paint component contained in the booth water are carried. A water treatment device for a water-washing type painting booth, comprising a reactor (5) arranged. 2. The crushing device (4) is an ultrasonic oscillator, and its ultrasonic oscillation surface (4a) is disposed facing or facing the flow of the circulating flow (F). Claim 1
A water treatment device for a water-washable painting booth as described. 3. A water treatment apparatus for a water-washing type painting booth according to claim 1, wherein said crushing device (4) is a rotary cutter blade, and a rotation speed thereof is selected to be 1000 rpm or more. 4. The reactor according to claim 1, wherein the reactor is formed in a film shape and is arranged along the flow of the circulating flow.
4. The water treatment device for a water-washable coating booth according to 2 or 3. 5. The flushing booth water according to claim 1, further comprising a centrifuge (18) for solid-liquid separation of the booth water treated in the treatment tank (2, 32). Processing equipment. 6. A treatment tank (32) for storing booth water drained from a water-washing type painting booth (6).
6. A water treatment system for a water-washable painting booth according to claim 1, wherein the booth water is formed by partitioning a part of the partition, and the booth water flowing from outside the partition is treated. apparatus.