JP3478875B2 - Operating method of coating cleaning equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the operation of a coating cleaning facility equipped with a cleaning device for capturing paint mist in the air with cleaning water and a cleaning water tank for storing cleaning water circulated to the cleaning device. Regarding the method.

[0002]

2. Description of the Related Art FIG. 9 shows a conventional cleaning equipment for painting.
Is a booth for painting, 2 is air A discharged from booth 1
Cleaning device that captures the paint mist inside with cleaning water W, 3
Is a washing water tank for storing the washing water W to be circulated to the washing device 2, and 10 is a centrifuge for dehydrating and separating the paint sludge S in the washing water while circulating the washing water W with the washing water tank 3. A dewatering device such as a separation type, and 13 is an in-tank agitating device for agitating the stored cleaning water W containing the paint sludge S in the cleaning water tank 3.

In this conventional equipment, when the cleaning water circulation operation is performed in which the cleaning water W is circulated between the cleaning device 2 and the cleaning water tank 3, the cleaning water tank 3 and the dehydrator are operated in parallel with the cleaning water circulation operation. Circulate the wash water W between the
The dewatering device 10 continuously separated and collected the paint sludge S.

Further, the in-tank agitator 13 also operates the wash water circulation operation so that the paint sludge S can be reliably sent to the dehydrator 10 together with the wash water W while avoiding the sedimentation and accumulation of the paint sludge S in the wash water tank 3. In parallel with this, it was constantly operating (see, for example, Japanese Patent Application Laid-Open No. 5-104058).

[0005]

However, in the above-described conventional operation method, compared with the type in which the paint sludge S in the stored cleaning water is separated from the cleaning water W in the cleaning water tank 3 by gravity separation (sedimentation separation or floatation separation). Although there is an advantage of facilitating the recovery process of the sludge S, the dewatering device 10 targets the dewatering process of the wash water having a low paint concentration (for example, several thousand ppm), in other words, the paint sludge S by the dewatering device 10. Since it is necessary to maintain the stored cleaning water W in the cleaning water tank 3 at a low paint content concentration (several thousands ppm or less) suitable for recycling in the cleaning device 2 by separating and collecting
There is a problem that equipment cost and operation cost increase because a dehydrating device 10 such as a centrifugal separator having a large processing capacity is required.

Further, the constant operation of the in-tank agitator 13 in parallel with the wash water circulation operation has been one of the factors that increase the operating cost.

In view of the above circumstances, the object of the present invention is as follows.

A first object of the present invention is to reduce the capacity required for a dewatering device in the recovery of paint sludge to reduce the equipment cost and the operating cost.

A second object of the present invention is to shorten the required operation period of the in-tank agitator to further reduce the operation cost.

[0010]

[Means for Solving the Problems]

[First Characteristic Configuration] A first characteristic structure of the present invention is for coating, comprising a cleaning device for capturing paint mist in the air with cleaning water, and a cleaning water tank for storing cleaning water circulated to the cleaning device. As a method of operating the cleaning equipment, in response to the stop of the cleaning water circulation operation of circulating the cleaning water between the cleaning water tank and the cleaning device, a replacement step of transferring the stored cleaning water of the cleaning water tank to a replacement water tank, A specific gravity separation step of separating the paint sludge and the wash water in the replacement water tank by specific gravity, and the purified cleaning water whose specific gravity is separated in the replacement water tank from the paint sludge in response to the restart of the cleaning water circulation operation from the replacement water tank. A return process of returning to the wash water tank,
And a sludge recovery step for recovering the separated paint sludge in the replacement water tank after the purified cleaning water is returned to the cleaning water tank by a dehydrator.

[Second Characteristic Configuration] A second characteristic configuration of the present invention is to identify a specific configuration suitable for carrying out the above-mentioned first characteristic configuration, and an in-tank stirring device equipped in the cleaning water tank. Is operated in a limited manner corresponding to the above-mentioned replacement process.

[0012]

[Action]

[Operation of First Characteristic Configuration] In the first characteristic configuration, the purified cleaning water that has been gravity-separated from the paint sludge in the replacement water tank in the gravity separation process is returned to the cleaning water tank in the return process to restart the cleaning water circulation operation. Only highly concentrated paint sludge remains in the replacement water tank.

Then, this high-concentration paint sludge is dehydrated by a dehydrator in a sludge recovery process after the return process and recovered.

[Operation of Second Characteristic Configuration] In the second characteristic configuration, the paint sludge is prevented from remaining in the cleaning water tank by operating the agitating means in the tank in accordance with the replacement process, and the paint sludge is washed with the cleaning water. At the same time, it is surely sent from the wash water tank to the replacement water tank.

[0015]

【The invention's effect】

[Effect of First Characteristic Configuration] According to the first characteristic configuration of the present invention, the paint sludge remaining in the replacement water tank at a high degree of concentration is treated by the dewatering device. Therefore, the dewatering device is required to recover the paint sludge. The ability of the dehydrator to be reduced, and this also makes it possible to downgrade the dehydrator, such as changing the dehydrator from a centrifugal separator to a filter using a simple filter. Can be reduced compared to the above-mentioned conventional operation method.

[Effect of Second Characteristic Configuration] According to the second characteristic configuration of the present invention, since the agitating device in the tank is operated in a limited manner corresponding to the replacement process, the agitating device in the tank is operated in parallel with the washing water circulation operation. As compared with the conventional operation method in which the tank is constantly operated, the operation cost of the in-tank agitator can be reduced, and thus the operation cost of the entire equipment can be further reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows a cleaning equipment for coating, 1 is a coating booth for coating an object to be coated (for example, an automobile body) a, 2 is a coating mist in air A discharged from the coating booth 1. It is a cleaning device that captures with water W.

Reference numeral 3 is a wash water tank for storing wash water W,
The paint-containing cleaning water W that has captured the paint mist in the cleaning device 2 returns to the one end side of the cleaning water tank 3 via the flow path 4, and from the other end side of the cleaning water tank 3 flows through the flow path 5 by the circulation pump P1. The cleaning water W is supplied to the cleaning device 2 via the cleaning water W.

Reference numeral 6 denotes a replacement water tank having the same capacity as the cleaning water tank 3, and the bottom portion of the replacement water tank 6 is formed in an inverted pyramid shape.

Reference numeral 7 is a flow path for sending the stored cleaning water W in the cleaning water tank 3 to the replacement water tank 6 by the pump P2, and 8 is the replacement water tank 6
The cleaning water W in the replacement water tank 6 is taken out from a predetermined position slightly higher than the bottom of the cleaning water tank 3
Reference numeral 9 is a flow passage for returning the settled paint sludge S from the lower end of the inverted cone-shaped bottom portion of the replacement water tank 6 by the pump P3.

Further, valves V1 and V2 are provided in the return passage 8 and the sludge take-out passage 9 described above.

Reference numeral 10 denotes a centrifugal type dehydrator for dehydrating the paint sludge S taken out from the sludge take-out channel 9, 11 is a collector for collecting the paint sludge S dehydrated by the dehydrator 10, and 12 is a dehydrator 10. This is a flow path for returning the cleaning water W separated from the paint sludge S to the cleaning water tank 3.

Reference numeral 13 denotes an in-tank agitator for agitating the stored wash water W in the wash water tank 3 to uniformly disperse the paint component in the wash water. In this example, the agitating blade 13a is rotated to agitate the wash water W. The rotary wing type is adopted.

Next, the operation of the above-mentioned coating cleaning equipment will be described for each step in (a) to (e) below.

(A) Washing water circulation operation process During the painting work in the painting booth 1, as shown in FIG. 1, almost all amount of the washing water W is held in the washing water circulation system extending between the washing water tank 3 and the washing device 2. Circulating pump P
The cleaning water circulation between the cleaning water tank 3 and the cleaning device 2 is continued by 1 so that the paint mist in the exhaust gas is captured by the cleaning water W in the cleaning device 2.

Further, in this process, the amount of the captured paint is successively brought into the cleaning water tank 3, but the in-tank stirring device 13 is stopped.

(B) Upon completion of the replacement stroke booth coating work period, the circulation of the cleaning water between the cleaning water tank 3 and the cleaning device 2 is stopped, and the agitating device 13 in the tank is operated to operate the cleaning water tank 3 The settling paint sludge S in No. 1 is again dispersed in the stored cleaning water W.

Then, as shown in FIG. 2, the pump P2 is operated to transfer almost all of the stored cleaning water W in the cleaning water tank 3 to the replacement water tank 6 together with the amount of the paint, and the in-tank agitator 13 causes the cleaning water tank 3 to operate. It will stop when the amount of stored water in the area has decreased to a certain extent.

In this example, when the wash water circulating operation between the wash water tank 3 and the washing device 2 is stopped, almost all of the wash water W in the wash water circulating system extending between the wash water tank 3 and the washing device 2 is washed water tank 3. Accumulates in the flow.

(C) Specific Gravity Separation Process During the suspension period of the booting coating work (for example, the time zone from the end time of one day to the start time of the next day), the wash water W containing the paint component transferred to the replacement water tank 6 Is left in a stationary storage state in the replacement water tank 6, whereby the paint component in the wash water is settled as sludge S at the bottom of the replacement water tank 6 as shown in FIG.

(D) Return stroke Prior to resuming the booth coating work (that is, resuming the cleaning water circulation operation accompanied therewith), as shown in FIG. 4, the supernatant purified cleaning water from which the paint sludge S has settled and separated in the replacement water tank 6. Only W is returned from the replacement water tank 6 to the cleaning water tank 3 through the return passage 8 by opening the valve V1.

If necessary, fresh wash water is replenished to the wash water circulating system extending over the wash water tank 3 and the washing apparatus 2 to restore the required amount of water in the wash water circulating system.

When the booth painting work is restarted, the circulation pump P1 is operated to restart the circulation of the cleaning water between the cleaning water tank 3 and the cleaning device 2.

(E) Sludge recovery process After returning the purified cleaning water W of the supernatant to the cleaning water tank 3, the paint sludge S remaining in the replacement water tank 6 (that is, the paint sludge having a high degree of concentration) is the valve V2. By opening the valve and operating the pump P3, the dewatering sludge S is continuously dewatered by the dewatering device 10 from the bottom of the replacement water tank 6 to the sludge dewatering passage 9.

Then, the treated low water content paint sludge S sent from the dehydrator 10 by this dehydration treatment is collected in the collector 1.
1, and the separated cleaning water W sent from the dehydrator 10 is returned from the flow path 12 to the cleaning water tank 3.

In this example, the dehydration process is carried out in parallel with the booth coating work during the booth coating work period, thereby reducing the required processing amount per unit time of the dehydration device 10, The dehydrator 10 is further downsized.

[Other Embodiments] Next, other embodiments will be listed. (1) Although various types such as a centrifugal separation type, a vacuum filtration type, or a press type can be adopted as the dewatering device 10, since the coating material sludge S to be treated has a high concentration according to the present invention. Alternatively, as shown in FIG. 5, the paint sludge S may be dehydrated by gravity filtration using a simple filter means 10a.

(2) In the above-mentioned embodiment, the rotary vane type was adopted as the in-tank agitator 13. However, as shown in FIG. 6, the water jet nozzle 13b such as an ejector nozzle is used as an in-tank agitator for the washing water tank 3. May be deployed at

(3) As shown in FIG. 6, the bottom of the wash water tank 3 is shaped so that the depth gradually increases toward the extraction side to the replacement water tank 6, and water is sent in one direction. The in-tank agitator 13 is arranged so as to send the settled paint sludge S to the deeper depth side by its water feeding action, and thereby the paint sludge S is sent to the replacement water tank 6 together with the wash water W in the replacement process. The efficiency may be improved.

(4) In the above embodiment, the produced paint sludge S is used.
However, the present invention can be applied to the case where the produced paint sludge S is floatable. In this case, in the specific gravity separation process, the paint sludge S is floated and accumulated in the replacement water tank 6. In the return stroke, the purified cleaning water W separated from the paint sludge S is taken out from the bottom of the replacement water tank 6.

The present invention can also be applied to the case where both the floatable paint sludge S and the sedimentable paint sludge S are produced. In this case, the paint sludge S floats in the replacement water tank 6 in the specific gravity separation process. In contrast to the accumulation and sedimentation, the purified cleaning water W is taken out from the replacement water tank 6 at a position slightly higher than the accumulation portion of the sedimentary paint sludge S in the return stroke.

(5) As shown in FIG. 7, for the purpose of extracting only the purified cleaning water W accurately and as much as possible, irrespective of the change in the accumulated amount of the paint sludge S in the return stroke.
The height of the water intake for taking out the purified cleaning water W from the replacement water tank 6 may be adjusted.

(6) As shown in FIG. 8, a plurality of replacement water tanks 6 are provided, and while some of the replacement water tanks 6'are carrying out the specific gravity separation process, other replacement water tanks 6'are carried out. The cleaning water circulating operation between the cleaning device 2 and the cleaning water tank 3 may be performed with the purified cleaning water W returned from the cleaning water tank 3 to the cleaning water tank 3.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

[Figure 1] Facility configuration diagram showing the state of circulation of wash water

FIG. 2 is an equipment configuration diagram showing a replacement process.

[Fig. 3] Facility configuration diagram showing specific gravity separation process

FIG. 4 is an equipment configuration diagram showing a return process and a sludge recovery process.

FIG. 5 is an equipment configuration diagram showing another embodiment.

FIG. 6 is an equipment configuration diagram showing another embodiment.

FIG. 7 is an equipment configuration diagram showing another embodiment.

FIG. 8 is an equipment configuration diagram showing another embodiment.

FIG. 9 is a facility configuration diagram showing a conventional example

[Explanation of symbols]

W wash water A air 2 cleaning equipment 3 wash water tank 6 replacement water tank S paint sludge 10 Dehydrator 13 In-tank agitator

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B05B 15/00-15/12 B05D 3/00 C02F 1/40

Claims (2)

(57) [Claims] 1. A cleaning device (2) for capturing paint mist in air (A) with cleaning water (W), and a cleaning water tank for storing cleaning water (W) circulated to the cleaning device (2). (3) A method for operating a cleaning equipment for painting, comprising: corresponding to a stop of a cleaning water circulation operation for circulating cleaning water (W) between the cleaning water tank (3) and the cleaning device (2). Then, the replacement step of transferring the stored cleaning water (W) in the cleaning water tank (3) to the replacement water tank (6), and the paint sludge (S) and the cleaning water (W) in the cleaning water in the replacement water tank (6). A specific gravity separation process for performing specific gravity separation, and purified cleaning water (W) that has been specific gravity separated from the paint sludge (S) in the replacement water tank (6) in response to the restart of the cleaning water circulation operation, the cleaning from the replacement water tank (6). Return process to the water tank (3) and purified cleaning water (W) A method for operating a coating cleaning facility having a sludge recovery process in which the separated paint sludge (S) in the replacement water tank (6) after being returned to the cleaning water tank (3) is dehydrated by a dehydrator (10) and recovered. . 2. The method of operating a cleaning equipment for coating according to claim 1, wherein the in-tank agitating device (13) provided in the cleaning water tank (3) is operated in a limited manner corresponding to the replacement process.