Sludge recovery structure

Abstract

To provide a sludge recovery structure for generating a water flow in a water tank by sending air to a bubble pump installed in the water tank.SOLUTION: A sludge recovery structure is realized in a wet coating booth comprising: a water tank; a bubble pump disposed at a predetermined position in the water tank; and an air supply device for supplying air to the bubble pump. The sludge recovery structure has adopted means that causes air to be discharged from the air supply device into the water tank through the bubble pump to generate a water flow in the water tank, thereby moving the sludge to a recovery space at a subsequent stage.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a sludge recovery structure in a wet paint booth. [Background technology]

[0002] When spray painting is performed in a wet paint booth, about 70% of the misted paint turns into excess paint (hereinafter sometimes referred to as "overmist") and remains in the booth as residual paint (hereinafter referred to as "sludge"). For this reason, sludge has traditionally been collected in wet paint booths using air currents generated by fans or water currents from water curtains or tanks.

[0003] However, in conventional sludge recovery methods that use water flow, the sludge in the tank that captures the overmist may not be recovered due to factors such as the water flow path and pressure drop. The sludge settles and accumulates, reducing the water flow and water circulation capacity, as well as worsening the water quality in the tank and causing a putrid odor. This requires maintenance such as periodically changing the water in the tank, which creates difficulties in terms of maintenance management and costs. Therefore, there was a need for a sludge collection structure that could effectively capture the released overmist while generating a strong water current inside the tank, thereby increasing the sludge collection efficiency and preventing water pollution.

[0004] In order to solve the above problems, a technical proposal has been made as described in Japanese Patent No. 4255331 (Patent Document 1). That is, Patent Document 1 proposes a technical proposal to clean the paint mist-containing air by scattering the surface cleaning liquid in the reservoir together with the flow-down cleaning liquid from the flow-down wall. However, according to the technical proposal in Patent Document 1, due to the structure in which the cleaning liquid on the surface flows in conjunction with the air flow, there is almost no water flow throughout the cleaning liquid in the reservoir, and the paint that has accumulated in the lower layer remains settled, so the above problem is not solved.

[0005] The applicant came up with the idea of ​​whether it is possible to recover the sludge that has sunk in the water tank without allowing it to settle in the conventional sludge recovery structure as described above. He focused on a bubble pump that generates a water current by releasing air in a certain direction underwater, and developed a sludge recovery structure that can improve the circulation capacity within the water tank while improving water quality by generating a water current by supplying air to a bubble pump installed in the water tank and pushing the sludge in the water tank toward the recovery space, thereby leading to the proposal of the "sludge recovery structure" of the present invention. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 4255331 Summary of the Invention [Problem to be solved by the invention]

[0007] In view of the above problems, an object of the present invention is to provide a sludge recovery structure in which air is supplied to a bubble pump installed in a water tank to generate a water current. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides a wet paint booth equipped with a water tank, in which a bubble pump is provided at a specified location in the water tank, and an air supply device is also provided for supplying air to the bubble pump, and a water current is generated in the water tank by ejecting air from the air supply device via the bubble pump into the water tank, thereby moving sludge to a collection space in the downstream stage.

[0009] In addition, the present invention provides a bubble pump comprising an outer pipe which is a cylindrical body penetrating in the longitudinal direction and which has an outlet for discharging water and an inlet for water to flow in, and an inner pipe, the inner surface of the inner pipe is filled with water, and at least a portion of the outer surface of the inner pipe is inside the outer pipe, the outer pipe is provided with an air inlet which penetrates from the outer surface to the inner surface and connects to an air supply device, the inner pipe is formed with a recess in the circumferential direction on the outer surface side and is provided with a plurality of air holes which penetrate the outer surface of the recess and the inner surface of the inner pipe, the air inlet and the recess are connected, the air holes are formed with an inclination towards the central axis of the inner pipe towards the outlet, and air is discharged from the air holes on the inner surface of the inner pipe, thereby sucking water into the inner pipe and generating a water current.

[0010] Furthermore, the present invention employs a means in which the bubble pump is provided with an extension pipe which is a cylindrical body penetrating in the longitudinal direction, and at least a portion of the outer surface of the extension pipe is inside the outer pipe.

[0011] Furthermore, the present invention employs a means in which a plurality of air inlet ports are provided in the outer pipe, and the same number of inner pipes as the air inlet ports are provided.

[0012] Furthermore, the present invention employs a means in which a plurality of the bubble pumps are provided.

[0013] Furthermore, the present invention employs a means for discharging air from the bubble pumps in different directions.

[0014] In general, using a bubble pump to collect sludge allows for both sludge collection and the supply of air into the water. Effect of the Invention

[0015] According to the sludge collection structure of the present invention, a bubble pump is provided at a specified location in the water tank, which makes it possible to generate a strong water current in the water, and has the excellent effect of effectively collecting sludge without the sludge remaining in the water tank or settling. Because the bubble pump has a simple structure, it is less likely to become clogged with sludge, even when using dirty water that contains a lot of sludge, and a stable water current can be maintained.

[0016] Furthermore, according to the sludge collection structure of the present invention, a recess is formed in the circumferential direction on the outer surface of the inner pipe, thereby forming an air reservoir in which air flowing in from the air insertion port is temporarily stored in the recess, thereby stabilizing the pressure of the air discharged from the multiple air vents and making it possible to continuously form a water flow with a constant pressure.

[0017] Furthermore, according to the sludge recovery structure of the present invention, the bubble pump is provided with an extension pipe, so that the water flow formed by the ejection of air passes through the extension pipe extending beyond the outer pipe, thereby contributing to the directionality and stability of the water flow released from the discharge port into the tank.

[0018] Furthermore, according to the sludge collection structure of the present invention, since the same number of inner pipes as the air inlets are provided, it is possible to more strongly increase the pressure of the water flow toward the discharge outlet by the air flowing in from each air inlet.

[0019] Furthermore, according to the sludge collection structure of the present invention, by providing multiple bubble pumps, it is possible to form multiple water currents in the water tank, which contributes to the collection of sludge that is scattered over a wide area.

[0020] Furthermore, according to the sludge collection structure of the present invention, the air is ejected in different directions by the bubble pumps, making it possible to form complex water currents within the tank, which helps to prevent sludge from accumulating throughout the tank.

[0021] Furthermore, by supplying air into the water, the proliferation of anaerobic bacteria in the sludge can be suppressed, and putrid odors caused by deterioration of water quality can be reduced.

[0022] In addition, there will be no need for maintenance such as changing the water in the tank three times a year, which will eliminate maintenance costs. [Brief description of the drawings]

[0023] [Figure 1] 1 is an explanatory diagram showing an embodiment of a sludge collection structure according to the present invention; [Diagram 2] FIG. 4 is an explanatory diagram showing another embodiment of a sludge collection structure according to the present invention. [Diagram 3] 1A and 1B are explanatory views and a cross-sectional view showing an embodiment of a bubble pump in a sludge recovery structure according to the present invention. [Figure 4] 11 is a cross-sectional view showing another embodiment of a bubble pump in a sludge collection structure according to the present invention. FIG. [Diagram 5] 11 is a cross-sectional view showing another embodiment of a bubble pump in a sludge collection structure according to the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The sludge collection structure 1 of the present invention is characterized in that it is provided with a bubble pump 10 at a specified location in the water tank 2 and employs a means for discharging air supplied from the air supply device 3 into the water tank 2 via the bubble pump 10. Hereinafter, an embodiment of a sludge collection structure 1 according to the present invention will be described with reference to the drawings.

[0025] The sludge collection structure 1 of the present invention is not limited to the embodiments described below, but can be modified as appropriate within the scope of the technical idea of ​​the present invention, i.e., within the scope of shapes, dimensions, materials, etc. that can achieve the same functional effects.

[0026] FIG. 1 is an explanatory diagram showing an embodiment of a sludge collection structure 1 according to the present invention, in which (a) is a plan view of the sludge collection structure 1 and (b) is a schematic sectional side view of the sludge collection structure 1. FIG. 2 is an explanatory diagram showing another embodiment of the sludge collection structure 1 according to the present invention, in which (a) shows an embodiment in which the bubble pump 10 is oriented toward one point, and (b) shows an embodiment in which the bubble pump 10 is oriented toward a location where sludge is likely to accumulate. FIG. 3 is an explanatory diagram and a cross-sectional view showing an embodiment of a bubble pump 10 according to the present invention, in which (a) is a plan view showing the structure of the bubble pump 10, and (b) is a cross-sectional view of the bubble pump 10. FIG. 4 is a cross-sectional view showing another embodiment of the bubble pump 10 according to the present invention, and in detail shows an embodiment in which an extension pipe 18 is connected to the bubble pump 10. FIG. 5 is a cross-sectional view showing another embodiment of the bubble pump 10 according to the present invention, and more specifically shows an embodiment in which air insertion ports 15 are provided at two locations.

[0027] The sludge collection structure 1 of the present invention is a wet paint booth equipped with a water tank 2, and moves sludge in the water tank 2 to a downstream sludge collection space 4 by a water current generated by supplying air to a bubble pump 10 provided at a designated location in the water tank 2. The wet painting booth is composed of a water tank 2, a painting space 5 where painting is carried out into the water tank 2, and a sludge recovery space 4 where sludge that has become mixed into the water in the water tank 2 due to overmist from the painting space 5 is separated and recovered.

[0028] The painting space 5 is a space where painting is performed on the workpiece W, which is the object to be painted, and a worker sprays the paint onto a water tank 2 arranged adjacent to the painting space 5. There are no particular limitations on the painting mode, but one possible mode is to spray compressed air from a paint pump 20 to the workpiece W via a paint injection gun 21, as shown in Figures 1 and 2. There are also no particular limitations on the paint used for such painting, and it is selected from synthetic resin paints using epoxy resins, urethane resins, etc., oil-based paints, cellulose nitrate paints, etc., based on the material of the workpiece W and the purpose of painting. The workpiece W is coated by this spray coating, but any paint that does not adhere to the surface of the workpiece W and becomes an over-mist falls into the water tank 2 under its own weight or floats in the air.

[0029] The water tank 2 is for collecting overmist generated by painting carried out in the painting space 5 . The water tank 2 is disposed adjacent to the painting space 5 and has a predetermined size. There is no limitation on the width of the water tank 2, but as shown in Figs. 1 and 2, it is preferable that the width of the water tank 2 is equal to or larger than the width of the painting space 5. There is no limitation on the length of the water tank 2, and it is sufficient if the length is sufficient to capture the over-mist when it falls naturally. For example, as shown in Figs. 1 and 2, a water curtain 22 is provided at a predetermined position of the water tank 2 so as to face the painting space 5, and the over-mist suspended in the air is captured and dropped into the water tank 2. By adopting such a mode, the amount of sludge remaining in the water tank is reduced, and the length of the water tank 2 can be shortened to make the size of the entire sludge collection structure 1 compact.

[0030] The water curtain 22 is provided above the water tank 2 facing the coating space 5, and serves to capture over-mist floating in the air. There is no particular limitation on the location where the water curtain 22 can be installed, but by installing it opposite the painting space 5, it can receive the overmist released from the painting space 5 head-on, making it possible to efficiently collect it. The structure of the water curtain 22 is not particularly limited, and any conventionally known structure may be used. For example, as shown in Fig. 1, water pumped up by a pump 23 may be constantly dropped downward from a predetermined height.

[0031] At predetermined positions in the water tank 2, one or more bubble pumps 10 for generating a water current within the water tank 2 are provided. The bubble pump 10 is a cylindrical tube that penetrates in the longitudinal direction and is composed of an outlet 11 for discharging water, an inlet 12 for water to flow in, and an air insertion port 15 that penetrates the cylindrical tube and is connected to an air supply device 3, thereby enabling air to be ejected toward the outlet 11 inside the bubble pump 10. Air flowing into the bubble pump 10 from the air supply device 3 through the air inlet 15 continues to be discharged from the outlet 11 into the water tank 2 while drawing in the surrounding water, so that the water discharged from the outlet 11 continues to flow into the bubble pump 10 from the inlet 12. As a result, a water flow is generated in the water tank 2 through the bubble pump 10, flowing from the inlet 12 to the outlet 11.

[0032] Furthermore, by disposing a plurality of bubble pumps 10 at predetermined locations in the water tank 2, it is possible to generate a plurality of water currents in any direction within the water tank 2. For example, as shown in Fig. 2(a), a mode is conceivable in which water currents are generated from a plurality of bubble pumps 10a toward a bubble pump 10b disposed behind the water curtain 22, the currents are merged, and the water currents are sent toward the sludge collecting space 4 by the water current from the bubble pump 10b, or as shown in Fig. 2(b), a mode is conceivable in which a plurality of bubble pumps 10 are disposed so as to have different discharge directions, and complex water currents are generated throughout the water tank 2, and the water currents are circulated while being sent to the sludge collecting space 4. By adopting this embodiment, it becomes possible to prevent the sludge that has spread over a wide area from accumulating and settling, which contributes to improving the efficiency of the sludge separation action in the sludge recovery space 4.

[0033] There are no particular limitations on the specific structure of bubble pump 10. For example, as shown in FIG. 3(a), a preferred embodiment is one in which one bubble pump 10 is formed by combining an outer pipe 13, which is a cylindrical tube passing through in the longitudinal direction, with an inner pipe 14. The bubble pump 10 formed in this manner comprises an outer pipe 13 having an outlet 11 and an air inlet 15, and an inner pipe 14 having an inlet 12 and a recess 16 formed in the circumferential direction of its outer surface. The inner pipe 14 is inserted into the outer pipe 13 so that an inlet 12 is provided at the end opposite the outlet 11 of the outer pipe 13, thereby forming a bubble pump 10 that extends from the inlet 12 to the outlet 11.

[0034] The air supply device 3 is a device that supplies air to the bubble pump 10. The structure of the air supply device 3 is not particularly limited as long as it is a structure capable of delivering compressed air, and a conventionally known structure may be used. When connecting to the bubble pump 10, piping for introducing air and connecting joints are naturally provided, and filters for removing dust and oil mist contained in the compressed air are appropriately provided depending on the structure and installation mode of the air supply device 3.

[0035] The outer pipe 13 is provided with an air inlet 15 connected to the air supply device 3, and an outlet 11 for discharging air discharged through the air inlet 15 and water pushed out by the discharged air. The shape of the outer pipe 13 is not particularly limited as long as it is a cylindrical tube penetrating in the longitudinal direction, but a cylindrical shape is generally selected. There is also no limitation on the diameter of the outer pipe 13, but since the inner pipe 14 is inserted into the outer pipe 13, it must be at least equal to or larger than the outer diameter of the inner pipe 14. There are no particular limitations on the materials for the outer pipe 13 and the inner pipe 14, but since they are permanently disposed within the water tank 2, water-resistant and corrosion-resistant aluminum, stainless steel, or a resin material such as polyvinyl chloride is suitable.

[0036] The inner pipe 14 is provided with an inlet 12 which allows water from the aquarium 2 to flow into the inner surface of the inner pipe 14, a recess 16 formed circumferentially on the outer surface which communicates with the air insertion port 15, and an air vent 17 which penetrates between the outer surface of the recess 16 and the inner surface of the inner pipe 14. The shape of the inner pipe 14 is not particularly limited as long as it is a cylindrical pipe penetrating in the longitudinal direction, like the outer pipe 13, but a cylindrical shape is generally selected. There is also no limitation on the diameter of the inner pipe 14, but since it is structured to be inserted into the outer pipe 13, it needs to be at least the same diameter as the inner diameter of the outer pipe 13 or smaller. By inserting the inner pipe 14 into the outer pipe 13, an air reservoir is formed between the recess 16 and the inner surface of the outer pipe 13 in which air flowing in from the air insertion port 15 can be stored, and the air is discharged onto the inner surface of the inner pipe 14 through the air vent 17. After the inner pipe 14 is inserted, a sealing process is applied to the boundary portion between the inner pipe 14 and the outer pipe 13 to prevent air that has flowed into the recess 16 from leaking out from the internal portion between the inner pipe 14 and the outer pipe 13, thereby providing airtightness and waterproofing.

[0037] The recess 16 is provided in the circumferential direction on the outer surface of the inner pipe 14 and is formed so as to communicate with the air inlet 15 of the outer pipe 13 . There are no particular limitations on the width or depth of recess 16, but it is preferable that at least the width is equal to or greater than the diameter of air inlet 15. For example, by making recess 16 approximately half the length of inner pipe 14, a wide space (air reservoir) can be formed to temporarily store the air flowing in from air inlet 15, and the pressure of the air discharged from air vent 17 can be stabilized. 3, a mode in which the wall surface of the recess 16 on the outlet 11 side is inclined is also suitable. By adopting such a mode and forming the air vent 17 in the inclined wall portion, it becomes possible to naturally determine the direction in which the air travels and to prevent the air discharged from the air vent 17 from accumulating in the pipe.

[0038] The air vent 17 discharges the air that has flowed into the recess 16 via the air inlet 15 to the inner surface side of the inner pipe 14 . The air vent 17 is a hole that generates a water current by discharging air that is generated by the air supply device 3, flows into the recess 16 through the air insertion port 15, and is temporarily stored therein, into the hollow portion (inner surface side) of the inner pipe 14. Moreover, by locating the air vent 17 at a location where it penetrates the recess 16 and the inner surface of the inner pipe 14 and can be discharged at least toward the exhaust port 11, it becomes possible to control the water flow generated by the discharge of air in the forward direction (water flow from the inlet 12 toward the exhaust port 11). For this reason, it is preferable to form the air vent 17 by penetrating from the recess 16 toward the exhaust port 11 with an inclination toward the central axis of the inner pipe 14. Specifically, it is preferable to form the air vent 17 so as to penetrate the recess 16 and the inner surface of the inner pipe 14 at an angle of about 60° with respect to the central axis of the inner pipe 14. The number and diameter of the air vents 17 are determined taking into consideration the necessary pressure of the water flow to be formed and the pressure distribution of the inflowing air, and are not particularly limited, but it is desirable to have, for example, about 4 to 10 air vents at equal intervals around the circumference of the recess 16. Also, by forming the total diameter of all the air vents 17 so that the discharge amount is approximately the same as the amount of air flowing in from the air insertion port 15, it is possible to stabilize the air pressure and the pressure of the generated water flow.

[0039] 4, it is also possible to extend the length of the bubble pump 10 by connecting an extension pipe 18 to the outlet 11. By adopting such an embodiment, the water is discharged while maintaining the pressure from the inlet 12 toward the outlet 11 for a long time, which has the excellent effect of improving the pressure stability and directionality of the water flow. 5, an embodiment may be considered in which an outer pipe 13 provided with a plurality of air inlets 15 has an inner pipe 14 with the same number of air inlets 15. That is, air flows in through air inlet 15A and is discharged through air vent 17A into the hollow part of inner pipe 14 to generate a water flow toward outlet 11, and then air flows in from air inlet 15B provided at the rear through air vent 17B to discharge air so as to further pressurize the water flow toward outlet 11, thereby enabling a strong water flow with increased pressure than usual to flow out into aquarium 2.

[0040] 2(a) and (b), there is no particular limitation on the number or direction of bubble pumps 10 disposed in water tank 2, and these are determined within a range in which sludge can be moved and collected to form a water flow toward sludge collection space 4, taking into consideration the size and shape of water tank 2, etc. In order to prevent sludge captured by water curtain 22 from flowing back toward coating space 5 after dropping into water tank 2, it is also preferable to dispose bubble pumps 10 directly toward sludge collection space 4 as shown in FIG. 2(a), or to dispose bubble pumps 10 near water curtain 22 as shown in FIG. 2(b).

[0041] As shown in Figures 1 and 2, an embodiment is also suitable in which an air supply fan 24 is provided in the coating space 5 and an exhaust fan 25 is provided at a predetermined position in the water tank 2, so that the over-mist suspended in the air is captured in the water tank 2 and the sludge is collected. In addition, if the water tank 2 is provided with a water curtain 22, a structure can be considered in which air is blown from the air supply fan 24 toward the bottom of the water curtain 22 and an exhaust fan 25 is provided at the upper part of the back side of the water curtain 22, so that air that has entered from below the water curtain 22 rises and is exhausted to the outside from the exhaust fan 25. The air blown from the air supply fan 24 toward the bottom of the water curtain 22 comes into contact with the water tank 2 and the water curtain 22 while containing the over-mist that has been stagnating in the upper part of the water tank 2, and a part of the over-mist is separated in the water and enters the back side of the water curtain 22 from the bottom of the water curtain 22. The air that has entered the rear side of the water curtain 22 rises due to the suction force of the exhaust fan 25 installed at the top, and is discharged to the outside. At this time, foreign matter such as over-mist contained in the air is naturally removed by a filter such as a mist catcher provided at the rear of the exhaust fan 25, although this is not shown in the figure.

[0042] The sludge recovery space 4 is disposed adjacent to the water tank 2 and is a space in which the sludge contained in the water of the water tank 2 is recovered. A sludge recovery device 6 is provided in the sludge recovery space 4, which separates and recovers the sludge contained in the inflowing water, and discharges it into the water tank 2 as clean water. The method of separating the water and the sludge by the sludge recovery device 6 is not particularly limited, and any conventionally known method may be used. The water containing sludge in the water tank 2 flows into the sludge collection space 4 by the water flow from the water tank 2 toward the sludge collection space 4, and is purified by passing through the sludge collection device 6 where the sludge is separated and collected, and then is discharged back into the water tank 2.

[0043] The main operation and function of the sludge recovery structure 1 consisting of the above-mentioned components will be described with reference to FIG. First, paint is released from the coating space 5 towards the water tank 2 onto the workpiece W. The paint that does not adhere to the workpiece W becomes overmist and mixes with the surface of the water tank 2 and the water curtain 22 and into the water. The overmist that has mixed into the water tank 2 sinks towards the bottom of the water under its own weight and becomes sludge, and the overmist that has mixed into the water curtain 22 flows into the water tank 2 as the water falls and becomes sludge. The water in the water tank 2 containing sludge flows into the sludge collection space 4 by a water current generated by a bubble pump 10 provided at a specified location in the water tank 2. The sludge is then separated and collected from the water by a sludge collection device 6 provided in the sludge collection space 4, turning the water into clean water, which can be reused as water for the water tank 2, or pumped up by a pumping pump 23 and used as a water curtain 22.

[0044] Next, the main operation and function of the bubble pump 10 disposed in the water tank 2 will be described with reference to FIG. First, air generated by the air supply device 3 flows into the recess 16 through the air inlet 15 and is temporarily stored in the air reservoir formed by the recess 16. The air stored in the air reservoir is discharged to the inner surface side of the inner pipe 14 via multiple air vents 17, but due to the inclination of the air vents 17, the air is discharged in the direction of the exhaust port 11. As the air discharged from the air vent 17 flows toward the exhaust outlet 11, the water filling the inner surface of the inner pipe 14 is also pushed out and moves toward the exhaust outlet 11. Furthermore, an amount of water equal to the amount of water that has moved flows in from the inlet 12, generating a water flow from the inlet 12 toward the exhaust outlet 11.

[0045] Although the sludge collection structure 1 according to the present invention has been described above, the present invention is not limited to the structures and aspects shown in the above-mentioned embodiments. For example, by equipping the device with a sensor capable of determining the sludge concentration in tank 2 and enabling bubble pump 10 to move automatically, bubble pump 10 will automatically move toward areas with high sludge concentrations and generate a strong water current, which contributes to water quality management throughout the tank while also preventing the accumulation of sludge in tank 2, providing excellent benefits. It is also preferable to provide a sensor capable of determining the sludge concentration in the water tank 2 and to automatically control the bubble pump 10, thereby automatically operating the bubble pump 10 closest to the area with a high sludge concentration, adjusting the strength of the air ejection, or sequentially and timely controlling the operating status of multiple bubble pumps 10 to generate an efficient water flow toward the sludge collection space 4. [Industrial Applicability]

[0046] The present invention can be used as a structure capable of preventing deterioration of water quality in a water tank due to sludge in any field requiring wet painting. Therefore, it is considered that the "sludge recovery structure" according to the present invention has great industrial applicability. [Explanation of symbols]

[0047] 1 Sludge collection structure 2. Aquarium 3 Air supply device 4 Sludge collection space 5 Painting space 6 Sludge collection device 10. Bubble Pump 10a Bubble Pump 10b Bubble pump 11 Outlet 12 Inlet 13 Outer pipe 14 Inner pipe 15 Air inlet 15A Air inlet 15B Air inlet 16 Recess 17 Ventilation holes 17A Ventilation hole 17B Ventilation hole 18 Extension pipe 20 Paint Pump 21 Paint injection gun 22 Water Curtain 23 Pump 24 Intake fan 25 Exhaust fan

Claims

1. In a wet paint booth equipped with a water tank, A bubble pump is provided at a predetermined location in the water tank, and an air supply device is provided to supply air to the bubble pump. A sludge collection structure characterized by generating a water current in a water tank by discharging air from an air supply device via a bubble pump into the water tank, thereby moving the sludge to a downstream collection space.

2. The bubble pump has an outlet for discharging water and an inlet for receiving water, The device is made up of an outer pipe, which is a cylindrical body penetrating in the longitudinal direction, and an inner pipe, The inner surface of the inner pipe is filled with water, At least a portion of the outer surface of the inner pipe is inside the outer pipe; The outer pipe is provided with an air inlet port that penetrates from the outer surface to the inner surface and connects to an air supply device. a recess is formed in the inner pipe in the circumferential direction on the outer surface side, and a plurality of ventilation holes are provided which penetrate the outer surface of the recess and the inner surface of the inner pipe; The air inlet and the recess are connected. The ventilation hole is formed with an inclination toward the central axis direction of the inner pipe toward the exhaust port, The sludge collection structure according to claim 1, characterized in that air is discharged from an air vent on the inner surface of the inner pipe, thereby sucking water into the inner pipe and pushing out the water from the inner pipe, thereby generating a water flow.

3. 3. The sludge recovery structure according to claim 2, characterized in that the bubble pump is provided with an extension pipe which is a cylindrical body penetrating in the longitudinal direction, and at least a portion of the outer surface of the extension pipe is inside the outer pipe.

4. 3. The sludge recovery structure according to claim 2, wherein the outer pipe is provided with a plurality of air inlet ports, and the inner pipes are provided in the same number as the air inlet ports.

5. The sludge recovery structure according to claim 1 , wherein a plurality of the bubble pumps are provided.

6. 2. The sludge recovery structure according to claim 1, wherein the directions in which the air is discharged by the bubble pumps are different from each other.

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