JPH02233109A - Paint sludge separation and recovery tank - Google Patents

Abstract

PURPOSE:To enhance the separation and recovery efficiency of sludge by providing a barrier member having a downwardly recessed cross-sectional shape to the lower part in a tank and arranging a supply port of raw water to be treated in such a state that the raw water to be treated is emitted upwardly toward the rear surface of the recessed part of the barrier member. CONSTITUTION:The supply port 11 of raw water to be treated containing paint components in a separated state is provided to the lower part of a separation and recovery tank 9 while a discharge port 12 discharging purified water after the separation of paint sludge is provided to the upper part of the tank 9 and the rising region (a) of the raw water to be treated in the tank is set to a paint sludge forming region and the surface layer part of the stored water in the tank is set to a formed paint sludge flotation and accumulation part. A barrier member 16 having a downwardly recessed cross-sectional shape is provided to the lower part in the tank and the supply port 11 is arranged in such a state that the raw water to be treated is emitted upwardly toward the rear surface of the recessed part of the barrier member 16. As a result, the separation and recovery efficiency of the sludge is enhanced and even the sludge of aqueous paint or that of high solid solvent type paint can be efficiently separated and recovered.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a supply port for treated raw water containing paint components in a dispersed state at the bottom of the paddle, and a drain port for discharging purified water after separation of paint sludge from a tank. The present invention relates to a paint sludge separation and collection tank provided at the upper part, with the rise area of treated raw water in the tank as a paint sludge forming area, and the surface layer of the water stored in the tank as a floating and depositing part of the formed paint sludge.

[Conventional technology]

Conventionally, in the paint sludge separation and recovery tank as described above, the supply port for treated raw water is opened upward in order to suppress the generation of large vortices in the tank that inhibit the formation of paint sludge and the floating accumulation of formed paint sludge. There is something. [Problem to be solved by the invention] However, it is difficult to separate sludge from water-based paints, which have a high water content and are easily dispersed, and sludge from solvent-based paints, which has a high specific gravity and which has become highly solid. Particularly when recovering raw water, it is required to keep the upward flow rate of treated raw water in the tank at a moderately low rate and to make it as uniform as possible over the entire rising area. Because the discharge dynamic pressure of treated raw water from the mouth remains at a fairly high position in the tank, it is difficult to achieve the required uniformity of the upward flow rate, and this has resulted in the sludge separation and recovery efficiency still being unsatisfactory. This was the main reason for not being able to obtain

In addition, with conventional paddles, the overall height of the paddle is large in order to ensure the height of the rising region sufficient to sufficiently attenuate the discharge dynamic pressure of treated raw water, which results in poor installation ease and high cost. There were also costly problems. Incidentally, in order to eliminate the discharge dynamic pressure of the treated raw water, we also attempted to install a horizontal plate that causes the discharged raw water from the upward supply port to collide with the raw water. However, the sludge dispersion and recovery efficiency could not be improved.

The purpose of the present invention is to improve the sludge separation and recovery efficiency through rational improvements, so that even water-based paint sludge and high solids solvent-based paint sludge can be efficiently separated and recovered. The advantage is that it allows the tank to be made smaller. [Means for Solving the Problems] The characteristic configuration of the paint sludge separation and recovery tank according to the present invention is that a supply port for treated raw water containing paint components in a dispersed state is provided at the bottom of the tank, and purified water after paint sludge separation is discharged. In a configuration in which the drainage port is provided at the top of the tank, the rising area of the treated raw water in the tank is the paint sludge formation area, and the surface layer of the water stored in the tank is the floating and depositing part of the formed paint sludge, a cross-sectional shape is provided at the bottom of the tank. A collision member having a downward concave shape is provided, and the supply port is arranged to discharge treated raw water upward toward the lower surface of the recess of the collision member, and its functions and effects are as follows.

[For production]

In other words, the treated raw water discharged from the supply port (11) toward the lower surface of the recess of the collision member (16) (see Fig. 2) collides with the lower surface of the recess of the collision member (16), and then collides with the lower surface of the recess of the collision member (16).
Due to the downward concave cross-sectional shape of l6), the vortex region is limited to the recessed part of the collision member (l6) and below it, and a strong vortex is formed in the recessed part and below the recess, and this collision and the subsequent vortex flow This formation effectively converts the dynamic pressure of the treated raw water discharged from the supply port (11) into static pressure.

Then, the lower edge of the downward concave collision member (16) and the tank wall (
9a), the treated raw water rises with static pressure (that is, with almost no influence from the dynamic pressure discharged from the supply port (11)), and as a result,
A rising region (a) of the raw water to be treated is formed in which the ascending flow rate is appropriately reduced and uniform throughout, and is extremely suitable for sludge formation and floating of the formed sludge.

〔Effect of the invention〕

In other words, due to the above effects, the paint sludge separation and recovery efficiency can be greatly improved compared to the conventional paint sludge separation and recovery tank, and the efficiency can be improved even with water-based paint sludge, high solids solvent-based paint sludge, etc. It is now possible to separate and collect it well. In addition, it is no longer necessary to ensure a large rise area height to attenuate the discharge dynamic pressure of treated raw water, and the overall height of the paddle can be made smaller than before, thereby improving installation ease and reducing costs. We have reached the point where we have been able to achieve a reduction in

〔Example〕 Next, an example will be described.

Figure 1 shows the equipment configuration of the painting equipment, where (1) is a painting booth, and in this painting booth (1) there is a painting room (2).
Below, there is a bending constriction flow 8 (
4) is provided with a paint mist removal device (5) that allows water to catch paint mist in the exhaust air by passing through the exhaust air at high speed.

(6) transfers the water (1) that has captured the paint mist to the flow path (7).
The water (W) in the upper tank of the stored water (1) of the storage tank (6), which is a storage tank that receives and stores paint components, is
The paint sludge formed and floated during the retention period in the stage N (6) is overflowed and sent from the stage tank (6) to the sludge separation and collection tank (9) via the channel (8). Water (1) flows through the flow path (10) into the tank (
6) to the flow pan (
3) and reused as water for capturing paint mist.

As shown in Figs. 2 and 3, the sludge separation and collection tank (9) contains treated raw water (water) containing paint components in a dispersed state.
A supply port (11) for water supplied from the in-process tank (6) is provided at the bottom of the tank, and a drain port (12) for discharging purified water (1) after paint sludge separation is provided at the top of the paddle. The rising area of the treated raw water (1) in the tank is used as the paint sludge formation area, and paint sludge is formed during the rising process of the treated raw water (1) in the tank, and the formed paint sludge is transferred to the surface layer of the water stored in the tank (1). It is designed so that the parts are floated and accumulated.

The floating and accumulated paint sludge (S) is removed by a scraping device (13
) is taken out from the slange separation and recovery tank (9) and sent to the filtration device (15) via the hopper (14).

In the lower part of the sludge separation and recovery tank (9), a collision member (16) with a bottomless circular male shape is arranged at the center of the tank in plan view, and the treated raw water supply port (11) is , collision member (
16) is arranged so that the treated raw water (1) is discharged upward toward the center of the lower surface. In other words, after the treated raw water discharged upward from the supply port (11) collides with the center of the lower surface of the collision member (16), the bottomless circular male shape of the collision member (16) causes the raw water to be discharged upward from the supply port (11). Due to the V-shaped cross-sectional shape), the vortex forming region is formed by the collision member (16
), a strong vortex is formed in the recess and the vicinity below the recess, and due to this collision and the subsequent formation of the vortex, the treated raw water (W) from the supply port (11) is Discharge dynamic pressure is effectively converted into static pressure.

From between the lower end edge of the collision member (16) and the tank wall (9a), the treated raw water (匈) rises with static pressure, and in the rising process, the collision member (16)
Since the width of the ascending flow path gradually expands due to the conical shape (inverted V-shaped cross section) on the upper surface side, the upward ascending flow rate gradually decreases while maintaining its uniformity, and the rising region expands. , and finally, the sludge is formed in the tank above the upper end of the bottomless conical collision member (16), and the sludge is formed so that the upward flow velocity is appropriately reduced and is uniform throughout. A rising region (a) of the treated raw water is formed which is extremely favorable for the floating of the treated raw water.

In the figure, (17) is a flocculant injection part for previously injecting a flocculant into the treated raw water (1) to be discharged from the supply port (11) into the sludge separation and recovery tank (9). The flocculant is effectively mixed with the treated raw water (W) by the formation of the above-mentioned strong vortex in the sludge separation and collection tank (9), and the reaction time is obtained in the uniform upward flow in the rising region (a). It reacts efficiently and stably, effectively contributing to the formation of paint sludge.

At the upper part of the sludge separation and recovery tank (9), a discharge port (12
) is formed over three sides of the tank (9) in plan view (the remaining 1
On the side, there is a path for removing floating accumulated sludge out of the tank by a scraping device (13), which prevents the occurrence of lateral water flow in the upper layer of the reservoir water, which has a negative effect on stable floating accumulation of paint sludge. In order to suppress it as much as possible, especially the layer (
This is to avoid generation of a large lateral water flow that runs across the center of layer (9) in plan view and extends between opposing sides of layer (9) toward drain port (12).

(18) serves as a weir to partition the floating and deposited part of the sludge (S), forms the upper edge of the drain port (12), and removes paint sludge from water (1) flowing out to the drain port (l2). It is a separation plate that separates the water from the drain port (12), starting from point b in the figure (the paint sludge located at this position is most likely to ride the horizontal water flow and flow out from the drain port (12) along with the water (1)). The composite vector (V,
This separation play} (18) is arranged so that the extension line of ) collides with the separation play} (18).

In other words, the paint sludge that has gained a lateral minute velocity during the rising process due to the influence of the lateral water flow toward the drain port (12) is also separated and collected toward the sludge floating and accumulating section due to the collision with the separation plate (18). Paint sludge is prevented from flowing out from the drain (12).

(19) is a separation plate for preventing the generation of eddy currents that occur when the upward water flow is diverted to the horizontal water flow toward the drain port (12), thereby preventing the water flow near the drain port (12). Prevent disturbance and perform the aforementioned separation play} (18)
The separation function is ensured and stabilized. In addition, (20) is water (1) (
This is an overflow weir that overflows (purified water from which paint sludge has been separated) and flows out to the drainage channel (2 liters), and this overflow weir (20) is used to separate and collect sludge during operation. ! (9) Stably maintain the level of stored water at a predetermined level.

On the other hand, the bottom of the sludge separation and recovery tank (9) is formed into an inverted conical shape, and a discharge port (22) for the settled paint sludge is provided at the lowest part of the bottom of the tank. During operation, a predetermined amount of water (1) smaller than the amount of treated raw water supplied from the supply port (l1) is constantly drained from this discharge port (22), and the settled paint sludge is discharged from the paddle along with this waste water. It is designed to be discharged.

In addition, when the operation of the sludge separation and recovery tank (9) is stopped, the valve (
23) is closed to stop drainage from the discharge port (22), the tank (9) is maintained in a water storage state, thereby preventing paint sludge from adhering to various parts of the tank in a dry state. ．． From the drainage outlet (12) to the drainage channel (21) via the overflow weir (20)
The purified water (1) discharged to the tank (6) is returned to the tank (6), and the settled paint sludge discharged from the outlet (22) and the settled paint sludge generated in the tank (6) are returned to the flow path ( 24
), (25) to the filtering device (I5).

As an example of water connection settings at various locations in the sludge separation and recovery tank (9), the sludge floating speed (v1) due to buoyancy is 0.0.
5 to 0.08 m/s, the treated raw water discharge water connection (Vi) from the supply port (11) is set to about 2.0 m/s,
The rising water range (Vu) in the rising area (a) is 0.05 mi.
s, and horizontal water connection (v2) to the drain port (12).
) is about 0.04 m/s as a general rule.

The filtration device (15) supplies paint sludge (S) sent from various places onto a series of filter media (27) sent by a conveyor device (26), and as the paint sludge is transported by the conveyor, the paint sludge contains Water is removed by gravity filtration, and the dehydrated paint sludge (S) is allowed to fall into the sludge collection container (28) from the conveyance terminal end.

Water (W) filtered and recovered in the filtration device (15) is returned to the loading tank (6) via the flow path (29).

In this type of painting equipment, the tank corresponding to the in-process tank (6) is generally used for flotation separation of paint sludge in this tank (prior to final flotation separation in the sludge separation and collection tank (9)). In order to ensure as long a residence time of treated raw water as possible for the preliminary floating fraction Ill), the tank is made large and the amount of stored water is considerably large compared to the amount of circulating water. Although the tank capacity is sufficient to receive and store the water that falls from the flow path system when the water circulation operation is stopped, the amount of water held in the circulation system including the in-process tank (6) is limited to the painting booth (1). The in-process tank (6) is made small in order to maintain the water quality within a predetermined allowable limit by purifying the water by collecting paint sludge as described above only for short-term operation such as one day or several days. As a result, the amount of water stored in the tank (6) during operation is significantly reduced compared to the general example described above.

In order to reduce the amount of water held in the circulation system by making the in-process tank (6) smaller, the in-process tank (1), including the water (1) that has fallen into the in-process tank (6) due to the water circulation operation being stopped, is Almost all of the stored water (W) in 6) is transferred to the flow path (30
) is used as a replacement tank (
At the same time, the water (1) transferred and stored in the displacement tank (31) is taken out in predetermined amounts at a time and heated and evaporated to concentrate and separate the paint components in the water.
2) is provided with a heating concentrator (33) for recovery.

In other words, in cases where the paint used in the painting booth (1) is water-based paint, even if paint sludge is efficiently separated and collected by the sludge separation and recovery tank (9), the circulating water (
When the water quality of the circulating water (1) drops to the permissible limit, almost all of the water held in the circulating system (1) is transferred to the replacement tank (31) and stored. Therefore, by newly supplying fresh water (1) to the circulation system including the in-process tank (6), and by reducing the amount of water held in the circulation system as described above, the water held in the circulation system (1) as described above is reduced. ) can be completed in a short time,
Therefore, treatment of the degraded water that has been transferred and stored in the replacement tank (31) will be performed separately from the circulation system using a heating concentrator (33), and a painting booth will be operated to treat the degraded water. It is possible to resume operation of the painting booth in a short time without having to stop the operation for a long time.

In the figure, (34) is a valve that opens when the water held in the circulation system (water stored in the work tank (6)) is transferred to the replacement tank (3l).

(35) is a replenishment water tank in which fresh water (W) to be supplied to the in-process tank (6) is stored in advance.

(36) is the paint mist capture water (
(37) is the injection part that continuously injects the PH adjusting agent and the primary treatment agent for (1), and (37) is the injection part that circulates from the in-process tank (6) to the downstream van (3) of the coating booth (1). This is an injection part that continuously injects a killer agent into the supplied paint mist trapping water (1).

In addition, the a-collecting agent as a secondary treatment agent injected into the treated raw water supplied to the sludge separation and recovery tank (9) has a predetermined upper limit when the paint component concentration in the treated raw water, more specifically, the concentration of fine paint flocs in the treated raw water. Intermittent injection is performed in which injection is started when the concentration of fine paint flocs reaches a predetermined lower limit value and stopped when the fine paint floc concentration falls to a predetermined lower limit value.

[Another example]

Next, another example will be listed.

(b) At the sludge separation and recovery tank (9), the supply port (11
The collision member (16) that causes the upwardly discharged treated raw water to collide with the lower surface of the recess may have a shape in which the downwardly concave cross-sectional shape is continuous in the cross-sectional view direction. (0) At the lower part of the sludge separation and collection tank (9) inside the station,
Collision members (16) each having a downwardly concave cross section may be arranged horizontally at a predetermined interval, and a supply port for discharging treated raw water may be provided to each of these collision members (16).

(c) In the collision member (16) having a downwardly concave cross-sectional shape, detailed structural improvements are made such as making the top of the upper surface side a circular arc cross-sectional shape and the inner part of the recess on the lower surface side having a concave circular cross-sectional shape. is optional.

Further, a brim portion for rectifying the flow may be provided on the upper surface side or the lower surface side of the collision member (16).

(2) In the sludge separation and recovery paddle (9), drain port (1
The shape and structure of 2) can be improved in various ways, and the configuration of the device for taking out the floating deposited sludge (S) out of the tank can also be improved in various ways.

(n) The overall equipment configuration incorporating the paint sludge separation and recovery tank of the present invention can be modified in various ways.

[Brief explanation of the drawing]

Claims (1)

[Scope of Claims] 1. Supply port for treated raw water containing paint components in a separated state (11
) is provided at the bottom of the tank, and a drain port (12) is provided at the top of the tank to discharge purified water after paint sludge separation. This is a paint sludge separation and recovery tank in which a steep layer of paint sludge is floated and deposited, and a collision member (16) having a downwardly concave cross section is provided at the bottom of the tank, and the supply port (1
A paint sludge separation and recovery tank in which the paint sludge separating and collecting tank 1) is arranged to discharge treated raw water upward toward the lower surface of the recess of the collision member (16). 2. The paint sludge separation and recovery tank according to claim 1, wherein the collision member (16) has an inverted V-shaped cross section. 3. Claim 1 or 2, wherein the tank bottom is formed into an inclined bottom, and a discharge port (22) for settled paint sludge is provided at the lowest part of the tank bottom.
The paint sludge separation and recovery tank described. 4. The paint sludge separation and recovery tank according to claim 1, 2 or 3, further comprising injection means (17) for injecting a flocculant into the treated raw water discharged and supplied into the tank from the supply port (11). 5. The collision member (16) according to claim 1, 2, 3, or 4, wherein the three-dimensional shape of the collision member (16) is formed into a bottomless conical shape, and the collision member (16) is arranged at the center of the tank in a plan view. Paint sludge separation and collection tank.