JPH0463721B2 - - Google Patents

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a purification device.

[Background technology]

For example, a car body painting line is equipped with a surface treatment process as a pre-process for the main painting process, such as removing welding debris adhering to the car body surface, improving the corrosion resistance of the car body surface, and improving the adhesion of paint during the main painting process. The aim is to improve the properties and electrodepositability of the coating. Therefore, in the surface treatment step, for example, a degreasing step using a surfactant and an alkali builder, a first water washing step, a chemical conversion step using zinc phosphate, etc., a second water washing step, etc. are sequentially performed.

In these processes, for example, the degreasing process, risers equipped with a large number of shower nozzles are arranged in line in the line direction surrounding the object to be treated, which is the car body, and the water is sent through these risers. A treatment liquid (fluid) is sprayed onto the car body surface through a nozzle to degrease it.

The processing liquid used for this purpose is collected in the degreasing tank, and guided again from the riser to the nozzle by the circulation pump to be used for degreasing. A variety of miscellaneous objects are mixed in, from large foreign objects such as thread waste, cotton waste, welding spats, and fine foreign objects such as iron powder. These foreign substances need to be removed before the circulation pump.

In order to remove these foreign substances, there are two
Layered mesh screens have been installed, and conventionally, these mesh screens have been used to remove all of the above-mentioned foreign substances, from large ones to small ones. Therefore, this mesh screen is usually 8~
We were trying to use a wire screen with a fine mesh of 10 mesh, but even though it was made of two layers, these screens alone were not able to effectively capture foreign objects, and many of the nozzles would become clogged early. It was hot. Since the screen has a fine mesh, it is easy for minute objects such as thread waste and cotton waste to get entangled in the mesh, and once they become entangled, they cannot be removed as they are. There was also the inconvenience of sudden clogging. As a result, conventionally, these screens were replaced with new ones once every 3 to 4 hours, and during that time,
The removed screens had to be manually cleaned, which was a very troublesome task. However, it goes without saying that if the mesh size of the screen is increased, the nozzle will quickly become clogged. Since the screen is made of a wire mesh, the screens may open due to pressure or flow rate, reducing filtration accuracy.

[Purpose of the invention]

In view of the above circumstances, an object of the present invention is to provide a purification device that can perform effective filtration and eliminate the need for maintenance.

[Disclosure of the invention]

In order to achieve the above object, the present invention provides a tank having an inlet for a fluid to be purified and an outlet for extracting foreign matter removed from the fluid, and a cylindrical body disposed within the tank. It has a large number of filtration ports on its circumferential surface, and its internal space communicates with the external space in the tank only through these filtration ports, and the fluid after filtration is led out. In the purification device equipped with a screen having a discharge port, the tank has at least its lower part tapered downward and has the foreign matter extraction port at its lower end, and the screen has a filtration passage. The opening is formed in the shape of a slit, and inside the opening, there are multiple stages of backwashing nozzles located above and below, which inject cleaning liquid toward the filtration port while rotating relative to the screen about its central axis. The gist of the present invention is a purification device characterized in that this backwashing nozzle has ejection holes in the form of vertically elongated elongated holes.

Hereinafter, the present invention will be explained in detail with reference to the drawings showing embodiments thereof.

FIG. 1 shows a cross-section of an embodiment of the purification device 1 according to the present invention, viewed diagonally from above, and FIG. 2 shows a flow sheet showing how the device 1 is incorporated into a surface treatment process. In this embodiment, the purification device 1 is incorporated into a degreasing system in the surface treatment process. This degreasing system is equipped with booth 2 located on the painting line.
The car body flows in the direction of the arrow. This booth 2 has risers 3 surrounding the vehicle body arranged in a row in the direction of the arrow.
A large number of shower nozzles (not shown) are installed on the side facing the vehicle body. A receiver 4 is installed on the lower side of the booth 2 to collect the processing liquid (fluid) and guide it to the degreasing tank 5. The degreasing tank 5 is designed to temporarily store the processing liquid to promote sedimentation of foreign substances mixed in the processing liquid, and to remove other foreign substances using the first screen 6. 1st screen 6
is formed of a wire mesh with a relatively coarse mesh of one or more meshes, and allows the passage of fine foreign matter. In other words, the removal of these fine foreign substances is left to the purification device 1.
The outlet of the degreasing tank 5 and the riser 3 are connected by a first pipe 11 equipped with a circulation pump 7, first and second valves 8 and 9, and a pressure gauge 10. The pump 7 has an inlet pressure of 3Kg/cm ² and a flow rate of 3000/cm 2 .
It runs in about minutes. The outlet side of the circulation pump 7 and the purification device 1 are connected by a second pipe 14 equipped with a third valve 12 and a pressure gauge 13, and during normal operation, the processing liquid (fluid) is transferred from the degreasing tank 5 to the riser. The purifier 1 is not directly returned to the purifier 1 through the second pipe 14.
supplied to

The purifying device 1 includes a top lid 15 whose top opening is removable.
It is equipped with a tank 16 which is closed with a. This tank 16 is
The upper part is cylindrical and the lower part is tapered downward, and this tapered part is the residue collecting part 17.
It is said that A treatment liquid inlet 18 for receiving the treatment liquid from the second pipe 14 is provided at the upper end of the tank 16, and a tip portion 18 is provided on the inner side of the inlet 18 and is approximately L-shaped when viewed from above. A circulation control plate 19 is arranged parallel to the inner circumferential surface of the tank, and allows the processing liquid from the inlet 18 to circulate along the inner circumferential surface of the tank 16, thereby making it easier for thread waste, line waste, etc. to float. ing. Floating and circling garbage is
After being introduced together with the processing liquid into a saucer 21 with a socket 20 facing slightly lower than the liquid level, it is sucked by a feed pump 22 through a third pipe 24 equipped with a fifth valve 23, and It is designed to be led to a paper filter 28 through a fourth pipe 27 equipped with an eighth valve 25 and a pressure gauge 26. The processing liquid after being filtered by the filter 28 is returned into the receiver 4 through the fifth pipe 29. The sludge such as welding debris that settles in the tank 16 is collected by the residue collecting part 17 into an extraction port 30 provided at the lower end of the tank 16, and then, together with a part of the processing liquid, a sixth valve 31 is provided. 6th
It is sucked out by the feed pump 22 through the piping 32 and fed into the paper filter 28 through the fourth piping 27. A seventh valve 33, which is a drain valve, is attached to the extraction port 30, and is closed during normal operation, and is temporarily opened to perform a drain function before backwashing, which will be described later. The drain port 34 is provided on the outlet side of the valve 33. The tank 16 is provided with a cylindrical second screen 35 at the center thereof. This second screen 35 is a cylindrical piece of punched metal with a large number of filtration holes 36 formed therethrough, and its upper end opening is closed by the upper lid 15. It is fixed in the tank 16. As shown in the enlarged view of FIG. 3, each of the filtration ports 36 has a width W of 1 mm and a length L of 25 mm.
These filtration ports 36...
are parallel to each other in a staggered arrangement. The arrangement has a width pitch P of 2 mm and a longitudinal end spacing S of 1 mm.
It is regularized under mm. The width W of the slit-like filtration port is 0.5 to 3 mm, and the length L is 15 to 40 mm.
mm, width pitch P is 1.5 to 3 mm, longitudinal end spacing S
The preferred tolerance range is 0.5 to 3 mm. Each filtration port 36 is oriented horizontally in its longitudinal direction in this embodiment. The bottom of the second screen 35 is closed with a bottom plate 37.
7 is approximately at the same level as the upper end level of the residue collecting portion 17. The internal space of the second screen 35 thus communicates with its external space in the tank 16 only through said filtration openings 36 . In the second screen, its filtration opening 36
The filtered processing liquid that has passed through is led out through a lead-out pipe 39 that communicates through a filtrate outlet 38 that is a central opening of the bottom plate 37, and this lead-out pipe 39 is provided so as to be taken out to the outside of the tank 16. It is being A seventh pipe (return pipe) 43 equipped with a pressure gauge 40, a flow meter 41, and a fourth valve 42 is connected between the outlet pipe 39 and the first pipe 11. It is designed to lead to riser 3... The second screen 35 is designed to be backwashed from the inside, and the means for backwashing is a backwashing nozzle 44, but in this embodiment, it is further provided with a scraper 45. ing. The backwashing nozzle 44 is arranged apart from the outside of the support shaft 46, and the support shaft 46 is made of a hollow pipe and protrudes long into the center of the tank 16 through the top cover 15. The support shaft 46 is rotatably supported by a bearing 47 attached to the upper lid 15, and a drive gear 50 of a variable speed machine 49 meshes with a driven gear 48 attached to the upper end of the support shaft 46. As a result, the support shaft 46 is rotationally driven. On the outer periphery of the support shaft 46, four rows of conductive pipes 51 are arranged on the upper and lower sides with a phase difference of 180 degrees when viewed from above.
... are installed horizontally in communication. The conduction pipes 51 in each row are arranged in one row with a fixed interval between the top and bottom, and the conduction pipes 51 in one row and the pipes 51 in the other row are as follows.
When viewed from the side, they are arranged in a staggered pattern. A backwashing nozzle 44 is attached to the tip of each conduction pipe 51 via a flange 52, and the ejection hole 53 of this nozzle 44 is as shown in FIGS. 4 and 5.
It has a long hole shape with a width A of 1 mm and a length (height) B of 25 mm. Each spout hole 53 of the backwash nozzle 44
are vertically elongated and placed at a distance C of 15 mm from the inner surface of the second screen 35, and the spray angles α are 30 degrees in the upper and lower directions so that the cleaning liquids partially overlap each other. The cleaning liquid for backwashing is supplied to the eighth pipe branched from the seventh pipe 43.
It is guided through piping 54. The eighth pipe 54 is provided with an eleventh valve 55, a pressure pump 56, a twelfth valve 57, and a pressure gauge 58, and
4 and the support shaft 46 are connected via a flexible shaft 59 and a rotary joint 60. A scraper 45 equipped with a soft brush 61 at the tip is attached to the outer circumference of the support shaft 46.
6 in a radial direction. This scraper 45 rotates 90 degrees ahead of the backwash nozzle 44 in one of the two rows in the circumferential direction, and the brush 61 at the tip rotates while scraping the inner peripheral surface of the second screen 35. This removes dirt and the like clogged in the filtration ports 36 to make backwashing by the backwashing nozzle 44 effective. In addition, the eighth pipe 54
Between the upper ninth valve 62 and the eleventh valve 55, there is a
A ninth pipe 64 with ten valves 63 is connected, and the tenth valve 63 is closed during normal backwashing, that is, when backwashing is performed with filtered processing liquid, but makeup water is required. When the ninth valve 62 is closed, it is opened and the industrial water supplied through the ninth pipe 64 is transferred to the eighth pipe 5.
4 into the support shaft 46 and jetting this industrial water from a backwashing nozzle, backwashing can be performed in addition to replenishment.
The upper lid 15 of the tank 16 is provided with an air vent 66 equipped with a thirteenth valve 65, which is opened at the same time as the seventh valve 33 is opened.

In normal operation, the second, seventh, tenth, and thirteenth valves 9, 33, 63, and 65 are fully closed, and the eighth valve 2 is fully closed.
5 is opened to 1/4, and the other valves are left fully open. As a result, booth 2
The used processing liquid (degreasing liquid) passes through the receiver 4 and is stored in the degreasing tank 5, and after undergoing the first stage of filtration by the first screen 6, it is transferred from the first pipe 11 to the second pipe by the circulation pump 7. 14. The first screen 6 removes relatively large foreign matter, but the purifying device 1 processes fine foreign matter. The processing liquid fed to the second pipe 14 is introduced into the tank 16 through the introduction port 18. At this time, since the processing liquid is circulated by the circulation control plate 19, thread waste, cotton waste, etc. are likely to float, and floating objects received by the feed pump 22 through the receiving tray 21 become paper. It is fed to the filter 28 and processed there. Note that the filter 28 is provided with a limit switch 67 for checking the throughput. The processing liquid guided to circulate within the tank 16 is
The welding spats descend as they go around, and if the welding spats have a high specific gravity such as chips, they will fall into the residue collection area 1.
7 and processed by a paper filter 28 by a feed pump 22. The processing liquid is filtered by the second screen 35 while circulating. This filtration is performed by foreign matter being caught in the numerous filtration ports 36, and these foreign matter are those that were not guided to the receiving tray 21 by the circulation, and those that were not guided to the receiving tray 21 due to the circulation, and those that naturally settled and were guided into the residue collecting section 17. These include things that were not done. These foreign substances include many such as thread waste and cotton waste, which are very easy to get tangled and cause clogging. Filtering port 36 on the plate material...
Since it is made into a cylindrical body by opening it, there is no need for it to become entangled. In other words, the screen is
If it is made of a net material as in the past, lint and the like will get stuck in the intersecting points of the knitting, and these lint and the like will get tangled around the single wire of the net material, but the second screen 35 According to this, there is no such thing, and it is just a natural state. As a result, the backwash nozzle 4
When the backwashing liquid (processing liquid) is injected from 4..., the residue (foreign matter) is relatively easily removed from the filtration port 36, and light substances float and are processed by the paper filter 28, and Heavy objects settle down and pass through the saucer 21 and residue collection section 17
will be processed along the route that passes through. In this embodiment, the backwash nozzle 44 has an elongated opening so that the spray showers overlap each other in the vicinity of the filtration passage 36, which is the injection destination, so that all the filtration passages are These backwashing effects are distributed to the ports 36. Since the residue accumulated in the filtration ports 36 is floated from the second screen 35 by the brush 61 in advance, the backwashing effect becomes more effective. The filtered treatment liquid is
It is supplied to the booth 2 following the piping 43 and the first piping 11. During normal operation, if the inlet pressure gauge 13 of the purifier 1 rises above the set pressure due to clogging of the screen, the circulation pump 7 is automatically stopped and a buzzer sounds. In this case, the first screen 6 is replaced with, for example, an 8-mesh one, and the pressure pump 56,
The feed pump 22 and the variable speed machine 49 are all stopped,
The third and fourth valves 12 and 42 are fully closed, the second valve 9 is fully opened, and the circulation pump 7 is driven.
This makes it possible to switch to the conventional circulation system and deal with pressure abnormalities. At this time, by backwashing separately, it is possible to easily return to normal operation. During this backwashing, the seventh valve 33 is opened and the treated liquid in the septic tank 16 is converted into oil cans and about three cans are drained. The 13th valve 65 is left fully open. Therefore, the variable speed machine 49 and the pressurizing pump 56
Turn on and start backwashing by recycling into the pipe. At this time, the feed pump 22 is activated. This backwash operation is performed for about 20 to 30 minutes. Industrial water can also be used instead of the treatment liquid.

As mentioned above, the purification device according to the present invention has the following features:
Since the filtration openings of the screen are slit-shaped, lint does not get stuck or get tangled, and it stays in place naturally. A backwashing nozzle is installed inside the screen that sprays cleaning liquid toward the filtration port while rotating relative to the screen, so the backwashing caused by this spray wrinkle removes the lint attached to the outer surface of the screen. etc. are effectively removed and become floating. This allows light objects to float and heavy objects to settle and be processed outside the screen. As a result, there is less clogging in the screen,
There is no need to regularly replace the screen, and the filtration action can be performed effectively at all times, and the processing liquid itself is reliably filtered, so this device can be used, for example, in the booth of a painting line as in the previous embodiment. If used, there is less risk of foreign matter clogging the shower nozzle. Conventionally,
45-50 out of 180 nozzles in the booth are sold in one week
However, by incorporating the purifier according to the present invention, only about 10 to 15 clogs occurred over a long period of one month. That is, the clogging rate is reduced, and
The period required for this has also been extended. The screen is not woven like a net, for example, 1
Since it is formed into a cylindrical shape from two sheets of board material,
The eyes do not open even when the pressure or flow rate increases,
Thereby, filtration accuracy is always kept constant. If the tank is conventionally formed with a horizontal wall surface, the settled foreign matter (residue) will remain there, but as in the present invention, the tank is formed in a tapered shape with the bottom facing downward. This allows foreign matter to flow smoothly to the outlet and be effectively disposed of.

In the embodiment, the longitudinal direction of the slit of the filtration port is horizontal, but it may be vertical or inclined. The tank can be arbitrarily configured according to the setting location, such as a large diameter type as shown in FIG. 6, or a small diameter type as shown in FIG.
From the viewpoint of reducing pressure loss on the screen surface and improving the dust removal effect, the large diameter type shown in FIG. 6 is preferable. The type shown in Figure 6 is Do/D=0.5~0.8, Lo/L=0.5
~1.0 is a preferred size ratio range. The screen may be oriented horizontally instead of vertically in the axial direction as in the embodiment.

〔Effect of the invention〕

As seen above, the purification device according to the present invention includes a tank having an inlet for the fluid to be purified and an outlet for extracting foreign matter removed from the fluid, and a cylindrical shape disposed in the tank. A body having a large number of filtration ports on its circumferential surface, the internal space of which communicates with the external space of the tank only through these filtration ports, and the fluid after filtration being taken out. In a purification device equipped with a screen having an outlet, the tank is formed in a tapered shape with at least its lower part facing downward, and has an outlet for extracting the foreign matter at its lower end,
The screen has a slit-shaped filtration opening, and there is a backwashing device inside the screen that sprays cleaning liquid toward the filtration opening while rotating with respect to the screen about its central axis. It has multiple stages of nozzles on the top and bottom, and this backwash nozzle has elongated ejection holes on the top and bottom, making filtration effective and eliminating the need for maintenance. can do.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the purification device according to the present invention, Fig. 2 is a flow sheet showing how this purification device is incorporated during the degreasing process, and Fig. 3 is the arrangement of filtration ports. Figure 4 is a side view showing the backwashing device, Figure 5 is a cross-sectional view taken along the - line in Figure 4, and Figures 6 and 7 are the sizes of the purifier tank and screen. It is an explanatory diagram showing each type. 16... Tank, 18... Inlet, 30... Outlet port,
35... Screen, 36... Filtration port, 38... Filtrate discharge port, 44... Backwash nozzle.

Claims (1)

[Scope of Claims] 1. A tank having an inlet for a fluid to be purified and an outlet for extracting foreign matter removed from the fluid, and a cylindrical body disposed within the tank and its circumferential surface. a screen having a number of filtration ports, the internal space of which communicates with the external space of the tank only through these filtration ports, and a discharge port for discharging the filtered fluid; In the purification device, the tank has at least a lower part thereof tapered downward and has an outlet for removing the foreign matter at the lower end thereof, and the screen has a filtration opening formed in a slit shape. In addition, there are multiple stages of backwashing nozzles located above and below that inject cleaning liquid toward the filtration port while rotating with respect to the screen about its central axis as a rotation center, and this backwashing nozzle is A purification device characterized by having ejection holes in the shape of elongated holes at the top and bottom. 2. A patent in which the screen is equipped with a scraper inside that rotates relative to the screen, and a brush attached to the tip of the scraper removes residue adhering to the filtration opening from inside the screen. A purification device according to claim 1.