JPH0653235B2 - Paint slag separator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention purifies wastewater from a wet paint mist removing device (a device for capturing paint mist in a gas with water) attached to a coating booth or the like. In order to reuse the purified water as water for mist capture by the paint mist removing device, the present invention relates to a device for separating and removing paint dregs contained in wastewater. A control device that provides a separation tank that floats and separates the contained paint slag by supplying air bubbles to water, and adjusts the water level in the tank so that only the floating separation paint slag flows out of the tank. Along with this, it is possible to efficiently separate and remove the paint slag, and to prevent the paint slag from adhering to the paint slag as compared with, for example, mechanically removing and collecting the floated or settled paint slag. About paint flocculate separation apparatus which can reduce the maintenance such as cleaning of.

[Conventional technology]

Conventionally, in the paint slag separation device as described above, the entire amount of waste water (water containing paint slag) from the paint mist removal device is directly supplied to the separation tank (for example,
(See JP-A-51-136726).

[Problems to be solved by the invention]

However, in order to ensure the separation of the paint dregs in the separation tank, there is a specific relationship between the water surface area of the separation tank and the amount of water supplied to the tank, and the amount of water supplied becomes large. The water surface area of the tank is proportionally large. However, if the amount of water that flows out together with the floating separation paint slag is kept as small as possible and all of the floating separation paint slag is to be smoothly discharged out of the tank, the water surface area in the separation tank cannot be increased so much (currently , 1.6m × 1.6m
However, the size of the auxiliary equipment such as a filter that separates the paint spill that flows out from the separation tank and the water content of the separation tank may be limited in terms of human maintenance. Since it is limited in capacity, it is usually necessary to connect a plurality of separation tanks in parallel to the paint mist removing device.

However, it is necessary to provide a water level adjusting control device for each separation tank and an additional device such as a filter for receiving paint slag flowing out of the tank. Then, a guide structure for evenly distributing and raising the bubbles, and a special structure that doubles as a bubble generator and a paint slag-containing water inlet are required.
Since the tank structure itself is complicated, equipping a plurality of separation tanks led to a large increase in the total equipment cost.

An object of the present invention is to significantly reduce the required number of separation tanks with respect to the amount of wastewater discharged from the paint mist removing device by rational improvement by simply adding a simple pretreatment structure.

[Means for solving problems]

The paint slag separating device according to the present invention is characterized in that the paint slag containing material is floated and separated by supplying bubbles to the paint slag containing water, and only the floating separation paint slag is removed from the tank by adjusting the water level in the tank by the controller. In addition to the separation tank to be discharged, a pretreatment tank equipped with a bubble generation nozzle for floating and separating the paint slag is provided, and for introducing the paint slag-containing water from the paint mist removal device to the pretreatment tank. A first flow path and a second flow path for circulating and supplying water from which the paint residue has been removed to the paint mist removing device are connected,
In addition, a collecting section for collecting the floating separation paint slag together with the overflow water is provided, and the paint slag-containing overflow collected in the collecting section is supplied to the separation tank, and the paint slag is removed from the separation tank. There is a fourth flow path for returning water to the paint mist removing device, and the operation and effect are as follows.

[Action]

In other words, the wastewater (water containing paint slag) from the paint mist removal device is introduced into the pretreatment tank, and the paint slag is floated and separated by air bubbles in the pretreatment tank, and the paint mist removed water is removed from the pretreatment tank. As the circulating supply to the equipment, the floating separation paint slag is collected in the collection part together with overflow water.

Then, only the paint dregs and the overflow water collected in the collection unit are supplied to the separation tank, and in the separation tank, the paint dregs are finally separated and removed by the floating separation by bubbles and the water level adjustment in the tank. Further, the paint slag removed water from the separation tank is circulated and supplied to the paint mist removing device together with the paint slag removed water from the pretreatment tank.

Therefore, the amount of water supplied to the separation tank is greatly reduced compared to the amount of wastewater from the paint mist removal device, which greatly reduces the number of separation tanks required for the amount of treated wastewater. .

Further, as for the pretreatment tank, the floating separation paint slag is caused to flow out to the recovery part together with the overflow water, so that the following (a), (b) and (c) are possible.

(B) It is not necessary to make a subtle adjustment of the water level in the tank, which is required to cause only the floating separation paint slag to flow out of the tank.For example, the amount of water introduced into the pretreatment tank and the amount of circulating supply water to the paint mist removal device You can do only the initial setting,
There is no need for complicated water level control devices such as those attached to individual separation tanks.

(B) Even if the water surface area in the tank is large, the floating separation paint slag can be smoothly discharged to the recovery section, and there is no restriction on the water surface area as in the separation tank. Can be unified.

(C) The layer separation accuracy between the layer of the floating separation paint slag and the water layer in the tank may be lower than the layer separation accuracy required in the separation tank in which only the floating separation paint slag flows out of the tank. A complicated structure such as a guide structure for increasing the uniform distribution of the bubble group or a special bubble nozzle structure, which is applied to the separation tank for ensuring the separation accuracy, is unnecessary.

〔The invention's effect〕

As a result, the required number of separation tanks that require a water level control device and a complicated auxiliary structure can be greatly reduced by adding a pretreatment tank with a simple structure as described in (a), (b), and (c) above. It has become possible to reduce the total equipment cost.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to FIG.

(1) is a coating booth for automatic spray coating of the object to be coated (A) conveyed by the conveyor by the interior coating robot (1A), and (2) is the exhaust gas from the coating booth (1). It is a paint mist removing device that traps paint mist contained in water.

In addition, (3) purifies the wastewater from the paint mist removal device (2), and uses the purified water as mist trapping water (w) again in the paint mist removal device (2). A paint slag separating device for separating and removing the contained paint slag.

The paint slag separator (3) has a pretreatment tank (5) that receives the entire amount of wastewater (water containing paint slag) from the paint mist remover (2) via the first flow path (4). , Its pretreatment tank (5)
And a plurality of separation tanks (6) for receiving the water containing the concentrated paint dregs and finally separating and removing the contained paint dregs.

The pretreatment tank (5) is equipped with a nozzle (7) that generates air bubbles for floating separation of the contained paint slag, and
At the downstream of the tank (5), a gutter-shaped collecting part (8) for continuously collecting the floating separation paint slag together with overflow water is attached.
The water from which the contained paint dregs have been separated and removed in the pretreatment tank (5) is carried along with the overflow to the recovery part (8) and continuously to the paint mist removing device (2) via the second flow path (9). It is configured to be circulated and supplied to.

On the other hand, for each of the separation tanks (6) that receive the concentrated paint slag-containing water recovered in the recovery unit (8) through the third flow path (10), the air bubbles for floating the paint slag are separated. A nozzle (11) that doubles as a generator and an inlet for water containing paint slag is installed, and the floating separation paint slag is removed by controlling the drain valve (13) based on the tank water level detection by the ultrasonic sensor (12). When a predetermined amount is accumulated, the water level in the tank is raised so that only the floating separation paint slag flows out to the dehydration filter (14), and after the completion of the outflow, unnecessary overflow to the dehydration filter (14) side is avoided. An automatic control device (15) that lowers the water level in the tank by a set width is attached to the.

In addition, each separation tank (6) controls the water level as described above to minimize the amount of water that flows out together with the floating separation paint slag to reduce the processing load of the dehydration filter (14), and to collect a predetermined amount of floating separation. In order to smoothly flow out all of the paint dregs, it is formed in a vertically long shape with the water surface area in the tank limited, and the separation tank (6) individual processing capacity is limited due to the restriction of the water surface area, A plurality of separation tanks (6) are connected in parallel to the pretreatment tank (5).

The paint slag that has been gravity dehydrated by the dehydration filter (14) is transported to a post-treatment facility and incinerated.

The water from which the paint dregs have finally been separated and removed in each separation tank (6) is returned to the pretreatment tank (5) through the fourth flow path (16) provided with the drain valve (13). After pretreatment tank (5)
The paint slag is separated and removed together with the water, and is circulated and supplied to the paint mist removing device (2) through the second flow path (9).

The amount of wastewater continuously introduced into the pretreatment tank (5) via the first flow path (4) and the paint mist removing device (2) from the pretreatment tank (5) via the second flow path (9). The amount of water continuously circulated and supplied is initially set so that they are almost equal to each other, and the amount of water almost equal to the amount of water returned to the pretreatment tank (5) through the fourth flow path (16) is equal to It is configured to overflow into the recovery unit (8).

Further, the water that has passed through the dehydration filter (14) is returned to the pretreatment tank (5) via the fifth flow path (17).

In the figure, (P ₁ ), (P ₂ ), and (P ₃ ) are pumps, and (18) is
It is a compressed air supply path to the air bubble generation nozzle (7) of the pretreatment tank (5).

(19) is a compressed air supply path to the air bubble generating nozzle (11) of the separation tank (6), and the air supplied from the supply path (19) is a nozzle through the third flow path (10). Supplied to (11). The nozzle (11) in the separation tank (6) also serves as a nozzle for ejecting upwardly the concentrated paint dregs-containing water supplied from the recovery unit (8) through the third flow path (10). The paint slag containing water in the concentrated state and the air are jetted in a mixed state to enhance the effect of separating and floating the paint slag by the air bubbles.

[Another embodiment]

 Next, another embodiment of the present invention will be described.

Although it is advantageous in terms of equipment cost to have one pretreatment tank (5), a plurality of pretreatment tanks (5) may be provided in parallel with the paint mist removing device (2) if necessary.

Various modifications can be made to the specific tank configurations of the pretreatment tank (5) and the separation tank (6), and the bubble generation nozzles (7), (11) equipped on both tanks (5), (6) Each specific structure and the specific structure of the recovery part (8) attached to the pretreatment tank (5) can be variously improved.

In order to make the overflow to the recovery part (8) stable, the fourth channel
Although it is easier to set the water level of the pretreatment tank (5) by returning the paint slag removed water from the (16) to the pretreatment tank (5), the fourth flow path (16) from the separation tank (6) ) May be connected to the second flow path (9) or directly to the paint mist removing device (2).

As an improvement of the paint slag separating apparatus according to the present invention, as shown in FIG. 2, by initially setting the opening of the drain valve (13), the levitation separation paint slag in the separation tank (6) is reduced as much as possible ( It may be possible to always let it flow out of the tank along with overflow of 1/10 or less of the amount of water introduced to the separation tank (6), preferably 1/30 or less). It can be applied to the case of a paint type (for example, a water-soluble paint) in which the slag particles do not stick to each other, and is advantageous in that a controller for adjusting the water level can be eliminated.

The paint dregs separating device according to the present invention can be applied to various types of paint mist removing devices as long as it is a wet paint mist removing device using a liquid such as water.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.
The figure is a schematic configuration diagram showing an improved example of the present invention. (2) …… Paint mist removing device, (4) …… First flow path, (5)…
… Pretreatment tank, (6) …… Separation tank, (7) …… Bubbling nozzle, (8) …… Recovery section, (9) …… Second channel, (10) …… Third channel, (15) …… Control device, (16) …… 4th flow path.

Claims (1)

[Claims] 1. A separation tank (6) is provided for separating airborne paint slag by supplying air bubbles to the paint slag containing water from a wet paint mist removing device (2), and the separation tank (6). On the other hand, a paint slag separation device equipped with a control device (15) for adjusting the water level in the tank so that only the swelling paint slag flows out of the tank. ) Is attached to the pretreatment tank (5), and the paint mist removing device is attached to the pretreatment tank (5).
A first flow path (4) for introducing water containing paint dregs from (2),
Also, the paint mist removing device for removing the water from which the paint dregs have been removed (2)
The second flow path (9) for circulating supply to the tank is connected, and a collecting part (8) for collecting the floating separation paint slag together with the overflow water is attached, and the paint slag-containing overflow water collected in the collecting part (8). And a third flow path (10) for supplying to the separation tank (6), and a fourth flow path for returning the water from which the paint slag has been removed from the separation tank (6) to the paint mist removing device (2) A paint dreg separation device provided with (16).