JP4928438B2 - Levitation separation apparatus and levitation separation method - Google Patents

Description

  The present invention relates to a levitating separation apparatus and a levitating separation method for separating foreign substances from a processing liquid in which floating foreign substances are mixed.

  2. Description of the Related Art Conventionally, for example, a production line such as an automobile has a painting process for painting a workpiece such as a car body. In this painting process, paint is applied to the workpiece by spraying paint from a painting gun at a painting booth. At this time, surplus paint that has not been applied to the workpiece is lowered to the floor surface by air flowing down in the painting booth. The floor surface of the painting booth is provided with a surplus paint collecting section having an industrial water supply channel, a drain channel, and an inclined surface for collecting the industrial water and surplus paint in the drain channel. The surplus paint is washed away with industrial water (hereinafter referred to as “treatment liquid”), collected, and discharged into a flotation separation tank of a flotation separation apparatus disposed outside the coating booth. The processing liquid is separated from the paint in the floating separation tank, and is supplied to the floor of the painting booth again by a pump and circulated.

  As a flotation separation device that separates surplus paint from a processing liquid as paint sludge (hereinafter referred to as “foreign matter”), a device that includes two separation tanks, a first flotation separation tank and a second flotation separation tank, is known. In this apparatus, the processing liquid containing foreign matter is supplied to the first floating separation tank to which the flocculant has been added in advance, and the foreign matter is floated and separated. The treatment liquid containing foreign substances in the first levitation separation tank is introduced into the second levitation separation tank, and the aggregation of foreign substances, that is, the separation of foreign substances from the treatment liquid is further promoted.

FIG. 6 is an enlarged view of a main part showing a skimmer installation state in a conventional levitation separation apparatus.
As shown in FIG. 6, a scum box 200 is arranged in the second levitation separation tank so that an opening for discharging foreign matter to the outside is positioned near the liquid surface, and the scum box 200 is swung toward the opening of the scum box 200. A skimmer 100 that scrapes foreign matter that has floated to the liquid surface is provided.
However, the foreign matter is highly sticky and easily adheres to the scum box 200 weir. In order to maintain the normal operation of the apparatus, a great deal of labor is required to periodically remove foreign substances adhering to the weir and skimmer 100.

In order to facilitate the flow of foreign matter into the scum box 200, the liquid level in the floating separation tank is preferably set higher than that of the weir. 200 flows into the inside. If it does so, there exists a problem that the processing liquid containing a large amount of foreign materials is supplied to the foreign material filtration tank provided in the downstream of the scum box 200, and a processing liquid overflows the processing capacity of the mesh metal mesh in a tank.
Furthermore, when a large amount of foreign-containing processing liquid is discharged from the scum box 200, the amount of the processing liquid supplied to the second flotation separation tank increases, and the amount of the flocculant increases accordingly. There is a problem that costs increase.

  As described above, as an apparatus for preventing the unnecessary treatment liquid from being discharged, for example, one disclosed in Japanese Patent Laid-Open No. 2002-166271 (particularly, paragraphs 0020 to 0024 and FIGS. 1 to 4). It has been known. In this document, when the skimmer arm squeezes foreign matter and approaches the scum box, the first sensor detects it, opens the electromagnetic valve of the foreign matter discharge pipe and discharges the foreign matter, and the skimmer arm is moved over the scum box. When the inflow of foreign matter into the scum box is completed, the second sensor detects this and closes the electromagnetic valve of the foreign matter discharge pipe, thereby preventing unnecessary processing liquid from being discharged.

However, in the floating separation apparatus as described in the above document, when the foreign matter is discharged, the water level in the settling tank is lowered by the drainage, so when the turning skimmer arm passes the scum box and discharges the foreign matter, The scraped foreign matter is rubbed against the tapered weir at the opening of the scum box. At this time, when the treatment liquid is paint drainage or waste oil, it is crushed by the skimmer and the edge of the scum box to become a thick sticker and adheres to the side wall, top surface, and skimmer of the weir and solidifies. The adhering foreign matter accumulates in a scum box weir and becomes enlarged, which makes it difficult to discharge the processing liquid containing the foreign matter.
Further, in the skimmer 100 of the conventional levitation separation apparatus shown in FIG. 6, the foreign matter is crushed by the skimmer 100 and the scum box 200, and is accumulated and accumulated on the skimmer 100 and the scum box 200. There is a problem that the foreign matter removal performance is lowered.

  Therefore, it is desired to provide an apparatus that solves the problems of the prior art.

  The present inventors have intensively studied to solve the above problems. As a result, a floating separation device and a floating separation method that prevent excessive treatment liquid from flowing out and prevent foreign matter from adhering to the scum box weir have been realized, and the present invention has been completed.

That is, as various aspects of the present invention, the following flotation separation apparatus and method are provided.
[1] A floating separation tank in which a processing liquid containing floating foreign substances is stored, and swirls along the liquid level of the processing liquid in the floating separation tank to scrape foreign substances floating on the liquid level. A floating separation apparatus comprising: at least one skimmer to be moved; and a scum box having an opening in the vicinity of the liquid level of the processing liquid and removing the foreign matter scraped by the skimmer from the liquid level. And a water level switching adjusting means for lowering the water level of the processing liquid when the turning skimmer is separated from the scum box in the turning direction, and for raising the water level of the processing liquid when the skimmer is close to the scum box in the turning direction. A flotation separator characterized by the above.
[2] The floating separation device according to [1], wherein a weir lower than other portions is formed in the opening of the scum box on the side where the skimmer approaches.
[3] The water level switching adjusting means is provided on the discharge path, the discharge path for discharging the processing liquid from the floating separation tank to the outside, at least one skimmer detection switch for detecting the position of the skimmer, The floating separation apparatus according to [1] or [2], further comprising: an electromagnetic valve that opens and closes the discharge path using a detection signal from a skimmer detection switch.
[4] The lowered water level is set below the weir, and the raised water level is set above the weir and below the upper end of the scum box [2] or [ 3].
[5] The floating separation device according to any one of [2] to [4], wherein a width of the skimmer in a longitudinal direction is longer than a width of the weir in a longitudinal direction.
[6] A levitating separation tank in which a processing liquid in which floating foreign matters are mixed is stored, at least one skimmer that swirls and scrapes the foreign matter that has floated on the liquid surface of the processing liquid, and scrapes by the skimmer. A scum box that discharges the foreign matter to the outside of the floating separation tank, and a floating separation method by a floating separation device that removes the foreign matter that has floated on the processing liquid in the floating separation tank. When the skimmer moves away from the scum box in the swiveling direction, the water level of the processing liquid is lowered, and when the skimmer approaches the scum box in the swirling direction, the water level of the processing liquid is raised to remove the foreign matter. Floating separation method.

According to [1] and [6], when the processing liquid in which floating foreign matter is mixed is sent to the floating separation tank and stored, the foreign matter floats on the liquid surface of the processing liquid, and from the processing liquid. To separate. In the vicinity of the liquid level of the processing liquid mixture in the floating separation tank, a scum box having an opening for discharging floating foreign substances scraped by a skimmer swirling along the liquid level from the liquid level is installed.
When the turning skimmer reaches a position away from the scum box in the turning direction, the water level switching adjusting means sends the processing liquid to the outside of the floating separation tank to lower the water level. For this reason, when the skimmer does not drop the foreign matter into the scum box, it is possible to prevent the processing liquid from being discarded from the scum box to the outside and prevent the excessive processing liquid from flowing out of the floating separation tank.
When the skimmer approaches the scum box in the swiveling direction, the water level switching adjusting means controls the water level of the processing liquid to be raised by stopping the outflow of the processing liquid sent to the outside of the floating separation tank. In this way, by adjusting the water level of the processing liquid by the water level switching adjusting means, when the turning skimmer squeezes the foreign matter into the scum box opening and drops it, the liquid becomes higher than the scum box weir. Surfaced. For this reason, the skimmer does not crush the foreign matter and attach it to the scum box, and the scraped foreign matter can be efficiently dropped into the opening and discarded.
Therefore, it is possible to reduce the amount of processing liquid that is excessively discharged from the scum box and to be discarded, and to increase the amount of processing liquid that is reused.

  According to [2], the foreign matter that has been lifted up by the skimmer and floated on the liquid surface is composed of a weir formed on the side closer to the skimmer, which is lower than other portions. It will flow into the scum box.

  According to [3], the water level switching adjusting means detects when the skimmer is in a predetermined position by the skimmer detection switch, and the electromagnetic valve opens and closes the discharge path by the detection signal from the skimmer detection switch, and the floating separation is performed. The processing liquid in the tank can be discharged from the discharge path to the outside, or the discharge can be stopped. For example, when the skimmer moves away from the scum box in the swiveling direction, the electromagnetic valve opens, discharges the processing liquid from the discharge path to lower the water level, and the skimmer moves close to the scum box in the swiveling direction. Control to raise the water level of the processing liquid by closing the electromagnetic valve. Then, as the swimmering skimmer approaches the scum box weir, the water level rises, and the foreign matter that floats on the liquid surface can be scraped to drop the foreign matter from the scum box opening. Since the foreign matter is discarded, it is possible to reduce the time for discarding the treatment liquid containing a large amount of foreign matter from the opening and to reduce the amount of the treatment liquid to be discarded.

According to [4], when the water level is lowered, the water level is kept below the weir. Therefore, when the skimmer collects the foreign matter, the excessive processing liquid does not flow out of the floating separation tank. Further, when the water level is raised, the water level is maintained above the weir, so that the skimmer does not adhere to the weir when the foreign material flows into the opening.

According to [5], the width of the skimmer is set longer than the width of the weir. For this reason, when the skimmer passes over the weir, the skimmer does not slide against the front end of the side wall of the scum box located on the left and right of the weir, and the skimmer does not come into contact with the upper surface of the weir, and foreign matter is crushed by the weir. There is no.

  According to the levitation separation apparatus and the levitation separation method according to the present invention, when separating foreign matter from the treatment liquid containing foreign matter, the treatment liquid can be prevented from flowing out excessively, and foreign matter adheres to the scum box weir. Can be prevented.

  The above aspects and advantages of the present invention, as well as other effects and further features, will become more apparent from the following detailed description of exemplary and non-limiting embodiments of the present invention with reference to the accompanying drawings. It will be clear.

It is the schematic which shows the whole structure of the coating equipment provided with the floating separation apparatus which concerns on embodiment of this invention. It is a principal part expansion schematic of the floating separation apparatus which concerns on embodiment of this invention. It is a principal part enlarged view which shows the installation state of the skimmer of the floating separation apparatus which concerns on embodiment of this invention. It is XX sectional drawing of FIG. It is a principal part perspective view which shows the floating separation apparatus which concerns on embodiment of this invention. It is a principal part enlarged view which shows the installation state of the skimmer in the conventional floating separation apparatus.

Next, the best mode for carrying out the invention (hereinafter referred to as “embodiment”) will be described with reference to FIGS.
Hereinafter, as an example of an embodiment of the present invention, when an automobile body is painted, unfixed surplus paint that has fallen on the floor of the painting booth is washed away with industrial water (treatment liquid), and the surplus paint (foreign matter) is removed. A case where foreign matter is floated and separated from the mixed processing liquid will be described as an example. The industrial water will be described as a treatment liquid, and the paint sludge that is an excess paint mixed in the treatment liquid will be described as a foreign substance. In addition, “foreign matter floating (floating) on the liquid surface” and the expression corresponding thereto are not only foreign matter floating on the surface of the liquid (above the liquid level) but also in the liquid close to the liquid surface (the liquid level). (Below) can contain foreign substances. A treatment liquid containing foreign matter that is floated and separated for reuse may be referred to as a “treatment liquid mixture”.

<< Painting equipment >>
As shown in FIG. 1, the painting facility 1 paints the vehicle body W with the painting robot 22 while conveying the vehicle body W with the conveyance device 21, and lowers the excess paint that has not been applied to the vehicle body W onto the floor surface 23 a of the painting booth 23. The equipment is collected while being washed away with the processing liquid, the paint mixed in the processing liquid is separated as a foreign substance, and the processing liquid mixture is purified and circulated for reuse. The painting facility 1 includes a painting device 2 for painting the vehicle body W in a painting line of an automobile, and a floating separation system A for separating foreign matter from a processing liquid containing excess paint (foreign matter) that has not been applied to the vehicle body W. And a flow passage 8 for sending the treatment liquid or the treatment liquid mixture to desired places.

  The coating device 2 is a paint booth 23 that can accommodate the vehicle body W, a transport device 21 that transports the vehicle body W into the paint booth 23, and sprays paint on the vehicle body W that is transported by the transport device 21. And a painting robot 22 that performs the work.

  The transfer device 21 includes, for example, a rail 21a laid in the painting booth 23, a transfer carriage 21b equipped with a drive motor, a sensor (not shown) for detecting the amount of movement of the transfer carriage 21b, and a painting robot 22. And a control device (not shown) for controlling the conveyance of the conveyance carriage 21b.

The coating robot 22 is controlled by data stored in a control device (not shown) based on the position of the transport device 21 and paints the vehicle body W, and a coating gun (paint spraying device) 22a that sprays paint. Having an arm.
The painting gun 22a sprays the paint stored in a tank (not shown) from the tip of the arm of the painting robot 22 through the paint supply pipe.

The coating booth 23 is for collecting the processing liquid containing the excess paint (foreign matter) discharged from the coating apparatus 2 while preventing the dispersion of the excess paint (foreign matter). The coating booth 23 has a sloped floor surface 23a formed so that the lowered processing liquid is automatically collected in the drainage port 23b, and a drainage port 23b disposed in the lowest place of the floor surface 23a. And a ceiling surface 23c on which an air ejection device 24 for lowering surplus paint that has not been fixed on the vehicle body W by being jetted downward to the floor surface 23a is provided.
The floor surface 23a is provided with a plurality of nozzles 81a that are installed at the opening end of the processing liquid supply path 81 for supplying the processing liquid for washing away the paint that has fallen on the floor surface 23a and that spray the processing liquid.

<< Floating separation system >>
As shown in FIG. 1, the levitation separation system A separates the treatment liquid mixture in which foreign matter (excess paint) discharged from the coating apparatus 2 is mixed into the treatment liquid and the foreign matter, and reuses the treatment liquid. It is a system to let you. The levitation separation system A is separated by a first levitation separation device 3 that performs a first separation in which foreign matters in a treatment liquid mixture are levitated and separated into foreign matters and a treatment liquid, and the first levitation separation device 3 separates them. A second levitation separation device 4 that performs a second separation to further separate the treatment liquid mixture (a treatment liquid containing a large amount of foreign matter) into a foreign matter and a treatment liquid, and dehydration treatment of the foreign matter separated by the second levitation separation device 4 And a filtration tank 9 for performing a third separation for filtration.

<First floating separator>
The first levitation separation device 3 floats and separates foreign matter in the treatment liquid mixture on the liquid surface, and supplies the clear treatment liquid below the first levitation separation tank 31 to the nozzle 81 a through the treatment liquid supply path 81. The liquid processing solution mixture containing a large amount of foreign matter is sent to the second levitation separation tank 41 via the supply path 83 by the float pump P2. The first levitation separation device 3 includes a discharge passage 82, a first levitation separation tank 31, a float pump P2, a supply passage 83, a return passage 84, a processing liquid supply passage 81, and a pumping pump P1. It is mainly composed.

The discharge path 82 is a pipe that is connected to the drain outlet 23 b and draws the processing liquid mixture discharged from the drain outlet 23 b into the first floating separation tank 31.
The first levitation separation tank 31 is a storage tank that stores the processing liquid mixture sent from the discharge path 82 and the return path 84 and floats foreign substances contained in the processing liquid mixture. During operation, it is configured to be able to store about 300 tons of processing liquid mixture. In addition, the capacity | capacitance of this 1st levitation separation tank 31 is the magnitude | size of the coating booth 23, the quantity of the process liquid which flows so that the floor surface 23a of the coating booth 23 may be covered, the quantity of surplus paint, and a paint and a process liquid. The amount is determined appropriately depending on the time required for separation. Above the first levitation separation tank 31, the discharge path 82, a return path 84, which will be described later, a float type pump P 2, and a supply path 83 are disposed. The first levitation separation tank 31 is arranged at a position lower than the second levitation separation tank 41 and the overflow tank 6.

One end of the processing liquid supply path 81 is connected to the lower layer of the first levitation separation tank 31, and the other end is connected to the nozzle 81a via the pumping pump P1.
The pumping pump P1 is connected to the processing liquid supply path 81 to pump up the clear processing liquid near the bottom surface of the first floating separation tank 31 and supply it to the nozzle 81a.

  The float pump P2 has a suction port disposed on the liquid level of the processing liquid mixture in the first levitation separation tank 31, and sucks foreign matter and the processing liquid mixture floating on the liquid level while containing air, It is a pump for sending to the second levitation separation tank 41 via the supply path 83 while forming. The float pump P2 is installed on the liquid level of the processing liquid mixture in the first levitation separation tank 31 by, for example, a gantry (not shown). The float pump P2 has a function of removing foreign substances from the processing liquid in the first levitation separation tank 31 because the suction port is disposed on the liquid level of the processing liquid mixture. Further, when the bubbles generated by the float pump P2 are sent to the second levitation separation tank 41, the aggregation of the foreign matters in the supply passage 83 is promoted, and the foreign matters on the inner wall in the supply passage 83 are removed. Prevents sticking.

<Second floating separator>
As shown in FIG. 1, the second levitation separation device 4 stores the processing liquid mixture sucked by the float pump P2 and sent from the supply path 83 in the second levitation separation tank 41 to adjust the water level switching. In this apparatus, the processing liquid is sent to the overflow tank 6 by the means 7 and the foreign matter is removed by the foreign matter removing means 5 to the filtration tank 9 while adjusting the water level. The second levitation separation device 4 includes a supply path 83, a second levitation separation tank 41, a foreign matter removal means 5, an overflow tank 6, and a water level switching adjustment means 7. The second levitating / separating device 4 is provided with at least a skimmer 52 and a scum box 53 that constitute a part of the foreign matter removing means 5.
The second levitation separator 4 corresponds to the “floating separator” described in the claims.

<< Supply path >>
The supply path 83 is a pipe for sending a treatment liquid mixture containing a large amount of foreign matter sucked by the float pump P2 into the feed well 43 and discharging it. One end of the supply path 83 is connected to the float pump P2, the other end penetrates the side surfaces of the second floating separation tank 41 and the feed well 43, and the other end is in the center of the lower layer in the feed well 43. It is arranged with the open end facing upward. An air-containing processing liquid supply path 86 connected to the overflow tank 6 is connected to the intermediate portion of the supply path 83 via a pressure pump P3.
The pressurizing pump P3 is for mixing and bubbling the air taken in from the atmosphere with the processing liquid supplied from the overflow tank 6. The processing liquid containing air is sent to the supply path 83 by the pressurizing pump P3 and stirred with the processing liquid mixture to promote the aggregation / growth of the foreign matter, and the foreign matter is sent to the second floating separation tank 41. The liquid floats up to the liquid surface, flows toward the inner peripheral side of the foreign matter processing cylinder 44, and flows so as to be efficiently scraped by the skimmer 52.

<< Second Flotation Separation Tank >>
As shown in FIG. 2, the second levitation separation tank 41 is stored in the first levitation separation tank 31 (see FIG. 1) and supplied with a treatment liquid mixture in which a large amount of floating foreign substances are mixed and stored. And is provided to separate foreign substances from the processing liquid. The second levitation separation tank 41 is a two-tank type storage tank in which a foreign matter processing cylinder 44 is installed in a tank fishing state in the tank body 42. The second floating separation tank 41 includes a tank body 42, a feed well 43, a foreign substance processing cylinder 44, a processing cylinder support member 45, an overflow weir 42 a, a foreign substance removal means 5, a discharge path 85, and an overflow tank. 6 and a filtration tank 9 is provided in the vicinity.
The second floating separation tank 41 corresponds to the “floating separation tank” described in the claims.

The tank body 42 is made of, for example, a rectangular metal container in plan view and has an upper surface opened (see FIG. 5). The tank body 42 is adjacent to the overflow tank 6 on one side via an overflow weir 42a for maintaining a predetermined amount of the processing liquid mixture in the tank body 42, and a scum box 53 is mounted on the opposite part. Has been.
In FIG. 1, the sizes of the second levitation separation device 4 and the second levitation separation tank 41 are exaggerated, and the capacity of the tank body 42 is compared with the capacity of the first levitation separation tank 31. It is small and is about 1/10 to 1/100.

  As shown in FIG. 2, in the feed well 43, the treatment liquid mixture containing a large amount of foreign matter in the first floating separation tank 31 discharged from the supply path 83 is upward from the center of the lower layer in the foreign matter treatment tube 44. It is a tube for giving directivity so that it may flow toward. The feed well 43 is a cylindrical member whose upper opening end is widened, and is welded so that its lower end closes to the center of the inner bottom of the second floating separation tank 41 and is provided vertically. The feed well 43 is installed in the second floating separation tank 41 in a state where it is submerged in the processing liquid mixture, and the upper half of the feed well 43 is arranged in the foreign matter processing cylinder 44. It should be noted that the upper end portion of the feed well 43 that has been expanded has the foreign matter floating from the feed well 43 flowing in the direction of arrow B toward the inner peripheral surface of the foreign matter processing tube 44, thereby improving the scraping efficiency of the skimmer 52. It is formed to make it. In the lower layer of the feed well 43, the discharge port of the supply path 83 is arranged upward, and the processing liquid mixture sucked up from the first floating separation tank 31 is directed toward the liquid level in the foreign substance processing cylinder 44. It is designed to be discharged.

  The foreign substance processing cylinder 44 is a cylindrical member suspended in the second levitation separation tank 41, and is fixed to the inner wall of the tank main body 42 by a processing cylinder support member 45 provided on the outer periphery. The foreign substance processing cylinder 44 is disposed in a state where the lower end portion is spaced from the inner bottom of the tank body 42 and is disposed around the feed well 43, and the upper end portion protrudes from the liquid level of the processing liquid mixture. The lower end portion of the foreign matter processing tube 44 is configured to prevent the foreign matter in the foreign matter processing tube 44 from flowing out of the foreign matter processing tube 44 and by rotating the inside of the foreign matter processing tube 44 as indicated by an arrow C. The diameter is reduced in order to allow time for the foreign matter in the treatment liquid mixture to aggregate and float and to separate more in the foreign matter treatment tube 44.

  The processing cylinder support member 45 is a member for installing the foreign substance processing cylinder 44 in the tank main body 42 in the air fishing state, and includes a plurality of metal rod-shaped members. One end of the processing cylinder support member 45 is welded to the outer peripheral surface of the foreign substance processing cylinder 44, and the other end is welded to the inner wall of the tank body 42.

<< Foreign matter removal means >>
As shown in FIG. 2, the foreign matter removing means 5 is a device that scrapes the foreign matter that has floated on the liquid level of the processing liquid mixture in the foreign matter processing cylinder 44 with a skimmer 52 and flows it into the scum box 53 to remove it. The foreign matter removing means 5 is mainly composed of a motor M, a skimmer arm 51, a skimmer 52, and a scum box 53.

  The motor M is a drive source for rotating the skimmer arm 51 at a low speed, and is installed on the motor support member 10 disposed at the upper center of the tank body 42 so as to straddle the tank body 42 (see FIG. 5). ). The motor shaft Ma of the motor M is loosely inserted into a bracket 42 b installed at the center upper part of the tank body 42, and the tip is connected to the center part of the skimmer arm 51 by a bolt.

<Skimer arm>
The skimmer arm 51 is composed of a plate member that is rotatably installed with respect to the upper peripheral edge in the foreign substance processing cylinder 44, and is horizontally installed so that the motor M can turn above the liquid level of the processing liquid mixture. . In the longitudinal direction of the skimmer arm 51, a pair of skimmers 52 (52a, 52b) are installed side by side. At both ends of the skimmer arm 51, operating rods 73 and 74 for operating skimmer detection switches 71 and 72 described later are installed.

<Skimmer>
The skimmer 52 is a member for turning and scraping the foreign matter floating on the processing liquid mixture in the foreign matter processing cylinder 44 along the liquid surface, and is bolted to the skimmer arm 51 via the connecting member 54. . The length of the skimmer 52 is longer than the radial length of the foreign matter processing cylinder 44 in the opening 53 a of the scum box 53. That is, the skimmer 52 is formed to be longer than the length of the foreign matter removal weir 53b, and slidably contacts the front end portion of the side wall of the scum box 53 positioned on the left and right of the foreign matter removal weir 53b when passing over the foreign matter removal weir 53b. The foreign matter removal weir 53b is formed so as not to contact the upper surface.
As shown in FIG. 3, the skimmer 52 is made of a flexible rectangular rubber plate, the lower end 52 c is slightly lower than the foreign matter removal weir 53 b of the scum box 53, and the water level of the processing liquid mixture is lowered. The liquid surface F2 is slightly immersed in the liquid surface F2 and is disposed at a position lower than the upper end portion 53c of the opening 53a.

<Scum box>
As shown in FIG. 4, the scum box 53 is a rectangular tube-shaped member for discharging the foreign matter scraped by the skimmer 52 from the liquid surface, and is provided for discarding the foreign matter. The scum box 53 has an opening 53a and a foreign matter removal weir 53b at the upper end, and a foreign matter discharge port 53d having a reduced diameter at the lower end. The scum box 53 is a shooter for sending the foreign matter flowing into the scum box 53 to the filtration tank 9. It has a function. The scum box 53 is fixed to the second floating separation tank 41 in a state of penetrating the side wall of the foreign substance processing cylinder 44 and the tank main body 42, and the upper end opening 53 a is near the liquid level of the processing liquid mixture in the foreign substance processing cylinder 44. The foreign matter discharge port 53d at the lower end is arranged above the filtration tank 9.

  The opening 53a has a rectangular shape that is long in the radial direction of the foreign matter processing tube 44 in plan view. For example, the foreign matter removal is arranged on one of the long sides where the skimmer 52 that rotates in the right direction (clockwise) approaches. A weir 53b is formed. The foreign matter removal weir 53b is formed lower than the upper end 53c (the other part of the opening 53a) (see FIG. 3).

  The filtration tank 9 is a tank for filtering and storing the foreign matter discharged from the scum box 53. In the floating separation system A (see FIG. 1), the third separation for separating the foreign matter from the processing liquid mixture. It is also a device that performs. This filtration tank 9 has a trapezoidal mesh wire net 91 for dehydrating and storing foreign substances, and has a discharge port 9a (see FIG. 2) for discharging the filtered processing liquid to the outside on the bottom surface.

<< Water level switching adjustment means >>
As shown in FIG. 4, when the skimmer 52 moves away from the scum box 53 in the swiveling direction, the water level switching adjustment means 7 lowers the water level of the processing liquid mixture to the liquid level F <b> 2 (see FIG. 3). When close to the swirl direction, it is an apparatus for adjusting the liquid level by raising the water level of the processing liquid mixture to the liquid level F1 (see FIG. 3). The water level switching adjusting means 7 includes a discharge path 85 for discharging the processing liquid from the second floating separation tank 41 to the overflow tank 6 (external), skimmer detection switches 71 and 72 for detecting the position of the skimmer 52, and a discharge path 85. And an electromagnetic valve V which is provided above and opens and closes by a detection signal from the skimmer detection switches 71 and 72.

The liquid level F1 shown in FIG. 3 is a position above the position of the foreign matter removal weir 53b and lower than the upper end portion 53c of the scum box 53. When the water level rises to F1, the foreign matter floats on the liquid surface which is higher than the foreign matter removal weir 53b. In this state, the foreign matter flows into the scum box 53 while increasing the flow velocity, and the foreign matter removal weir It flows into the opening 53a without contacting and adhering to 53b.
On the other hand, the liquid surface F2 is slightly higher than the lower end portion 52c of the skimmer 52 to scrape foreign substances that have floated to the processing liquid whose water level has fallen, and the lower part of the skimmer 52 is immersed so as to attract foreign substances that float to the processing liquid mixture. It is a position below the position of the foreign matter removal weir 53b at a height that can be obtained.
In addition, the difference between the liquid level F1 when the water level of the treatment liquid mixture rises and the liquid level F2 when it falls is, for example, about 2 cm.

As shown in FIG. 4, the skimmer detection switches 71 and 72 are configured so that the operating rods 73 and 74 that rotate when the skimmer 52 is in a position in the angle range of 30 to 45 degrees with respect to the scum box 53 are close to each other. It is a switch that opens and closes. The skimmer detection switches 71 and 72 are installed on the upper part of the outer wall surface of the foreign matter processing cylinder 44 and are electrically connected to the electromagnetic valve V, respectively.
The skimmer detection switch 71 operates when the skimmer 52 approaches the scum box 53 in the turning direction, closes the valve of the electromagnetic valve V, and the processing liquid in the second levitation separation tank 41 flows from the discharge path 85 to the overflow tank 6. It is a switch that prevents the water from flowing into the water and raises the water level. The skimmer detection switch 71 sets 45 degrees to the scum box 53 on the outer periphery of the foreign matter processing cylinder 44 on the side where the skimmer 52 rotating in the right direction approaches the scum box 53 extending in the radial direction of the foreign matter processing cylinder 44. It is arranged at the position to make.
The skimmer detection switch 72 is activated when the skimmer 52 is separated from the scum box 53 in the turning direction, and opens the valve of the electromagnetic valve V, so that the processing liquid in the second levitation separation tank 41 is discharged from the discharge path 85 to the overflow tank 6. It is a switch that lowers the water level in such a way as to flow. The skimmer detection switch 72 has a 45 degree angle with the scum box 53 on the outer periphery of the foreign matter processing cylinder 44 on the side away from the skimmer 52 rotating in the right direction with respect to the scum box 53 extending in the radial direction of the foreign matter processing cylinder 44. It is arranged at the position to make.

The discharge path 85 is a pipe for sending the purified processing liquid between the foreign substance processing cylinder 44 and the tank body 42 to the overflow tank 6. The discharge path 85 is disposed through the overflow weir 42a, one end is disposed at the position of the liquid level F2 in the processing liquid between the foreign matter processing cylinder 44 and the tank body 42, and the other end is an electromagnetic valve. It is arrange | positioned above the overflow tank 6 via V (refer FIG. 2). That is, the discharge path 85 is disposed at a position where the processing liquid naturally flows when the processing liquid rises above the liquid level F2. As shown in FIG. 4, the discharge path 85 is disposed at a position facing the scum box 53 in the second floating separation tank 41.
The electromagnetic valve V controls the flow of the processing liquid by opening and closing the discharge path 85.

The overflow tank 6 is a tank that temporarily stores the processing liquid that has flowed from the discharge path 85 and the processing liquid that has flowed over the overflow weir 42a when the processing liquid in the tank body 42 increases. . A return path 84 for returning the processing liquid to the first floating separation tank 31 (see FIG. 1) and an air-containing processing liquid supply path 86 are installed in the lower layer of the overflow tank 6. The overflow tank 6 is located at a position where the level of the processing liquid in the overflow tank 6 is lower than the level of the processing liquid in the second floating separation tank 41 and higher than the level of the processing liquid in the first floating separation tank 31. It is installed to become.
The return path 84 has one end (first end) side disposed in the processing liquid of the overflow tank 6, the other end (second end) side is disposed on the first floating separation tank 31, and the second end is first Arranged at a position lower than one end, the treatment liquid naturally flows into the first levitation separation tank 31.

  The overflow weir 42a is for allowing the processing liquid to flow into the overflow tank 6 when the liquid level of the processing liquid in the tank body 42 exceeds the upper limit (that is, the liquid level F1). The overflow weir 42a is formed by opening a part of the side wall of the tank body 42 and fixing a plate member with a bolt to the opening. The plate material constituting the overflow weir 42a serves as both a part of the side wall of the tank body 42 and a part of the side wall of the overflow tank 6, and the upper end portion has a height substantially equal to the upper limit height of the liquid surface of the processing liquid. It is arranged at the position (F1).

<< Action >>
Next, the operation of the painting facility 1 will be described with reference to the drawings.
First, as a preparatory stage, a predetermined amount of the processing liquid mixture is put in the first flotation separation tank 31 shown in FIG. 1, and a foreign material (paint) separating agent is mixed into the processing liquid mixture to float and separate the foreign materials. Is made.
When the coating equipment 1 is operated, the air ejection device 24, the pumping pump P1, the float pump P2, the pressure pump P3, and the motor M are operated, and the processing liquid is applied to the coating booth 23 and the first floating separation tank 31. And the second levitation separation tank 41.

  Then, the vehicle body W is transported into the painting booth 23 by the transport device 21. When the vehicle body W is transported to the reference point of the painting booth 23, its position is detected by a sensor (not shown), and the painting robot 22 sprays the paint from the painting gun 22a.

  When this coating is performed, surplus paint is lowered to the floor surface 23a by the air blowing device 24. The surplus paint that has fallen to the floor surface 23a is washed away by the processing liquid sprayed from the nozzle 81a by the pumping pump P1 before adhering to the floor surface 23a, and is separated from the drain port 23b through the discharge path 82 to the first floating separation. It is sent to the tank 31.

  In the first levitation separation tank 31, the surplus paint in the treatment liquid is aggregated as foreign matter by the action of the separating agent, and almost floats on the liquid surface. As the float type pump P2 sucks the processing liquid mixture on the liquid level, the foreign matter floating on the liquid level flows and gathers from the lower side of the discharge path 82 toward the float type pump P2, and enters the supply path 83. It is sent to the feed well 43.

  In addition, the processing liquid near the bottom of the first levitation separation tank 31 contains almost no foreign matter due to separation. This processing liquid is supplied again to the coating apparatus 2 via the processing liquid supply path 81 by the pumping pump P1, and is reused for washing away the paint that has fallen to the floor surface 23a.

  The treatment liquid mixture containing a large amount of foreign matter near the liquid surface sucked by the float pump P2 is discharged into the feed well 43 while being mixed with bubbles of air sent into the supply path 83 by the pressure pump P3. Is done. The discharged processing liquid mixture flows from the feed well 43 toward the liquid surface on the inner peripheral surface of the foreign matter processing cylinder 44 in the direction of arrow B. The foreign matter whose aggregation has been promoted while being agitated by the bubbles in the supply path 83 further grows in the foreign matter treatment tube 44, and in the vicinity of the liquid surface, floats as a foreign matter having a large particle diameter, Collect on the inner peripheral surface of the foreign matter processing tube 44.

  As described above, when the processing liquid mixture in which the foreign matters are mixed is stored in the second levitation separation tank 41, the buoyant foreign matters float on the liquid surface, so that the clear processing liquid and the foreign matters are separated. To separate. In the tank main body 42, the foreign matter concentrates on the liquid surface in the foreign matter processing cylinder 44, and is hardly contained in other processing liquids. That is, the treatment liquid having a very low concentration of foreign matter descends between the foreign matter treatment tube 44 and the feed well 43 as indicated by an arrow C, and the foreign matter treatment tube 44 is removed from the lower end opening of the foreign matter treatment tube 44. It flows between the tank body 42.

  On the liquid level in the foreign matter processing cylinder 44, the skimmer arm 51 is rotated by the motor M, and a pair of skimmers 52 (52a, 52b) are swiveled. For example, when the skimmer 52b moves away from the scum box 53 shown in FIG. 4 in the turning direction and the operating rod 74 approaches the skimmer detection switch 72, the skimmer detection switch 72 is turned on to operate the electromagnetic valve V, and the valve open. Then, the purified processing liquid flows into the discharge path 85 having an opening at a position lower than the liquid level F <b> 1 and is sent into the overflow tank 6. Further, the processing liquid in the overflow tank 6 is returned to the first floating separation tank 31 from the return path 84.

  When the skimmer 52a shown by a solid line in FIG. 4 further turns and the operating rod 73 comes close to the skimmer detection switch 71, the skimmer detection switch 71 is turned on to operate the electromagnetic valve V and the valve is closed. Then, since the processing liquid mixture in the tank body 42 is continuously fed from the supply path 83 (see FIG. 2), the water level of the processing liquid mixture rises as the skimmer 52a approaches the scum box 53 in the turning direction. To do. As described above, the foreign substances are concentrated on the inner peripheral surface of the foreign substance processing cylinder 44. The skimmer 52a turns while scraping the foreign matter floating on the liquid surface of the processing liquid mixture, and causes the foreign matter to drop into the scum box 53 from the foreign matter removal weir 53b.

When the skimmer 52a passes in the vicinity of the foreign matter removal weir 53b, the water level of the processing liquid mixture rises above the foreign matter removal weir 53b to smoothly discharge the foreign matter into the scum box 53 as shown in FIG. It is adjusted so that it rises to the position of the liquid level F1. As a result, the foreign matter floats up to the liquid level F1 of the processing liquid mixture located above the foreign matter removal weir 53b, and thus exists in the processing liquid mixture above the lower end portion 52c of the skimmer 52. For this reason, foreign matter lumps (a lump of paint) are prevented from being crushed and adhered to the outer wall and upper surface of the foreign matter removal weir 53b by the lower end portion 52c of the skimmer 52, and smoothly dropped into the scum box 53. Will be discharged. Further, the foreign matter removal weir 53b (the side on which the skimmer 52 approaches) is formed lower than the upper end portion 53c (the other portion of the opening 53a) of the opening 53a, so that the skimmer 52 does not come into pressure contact and the foreign matter is removed. Adherence of foreign matter to the weir 53b can be prevented.
Therefore, the skimmer 52 and the opening 53a of the scum box 53 having the above-described configuration can prevent the foreign matter removal performance from deteriorating, and eliminate the need to remove the foreign matter attached to the foreign matter removal weir 53b and the skimmer 52. be able to.

  As shown in FIG. 2, the foreign matter dropped into the scum box 53 is dropped into the mesh wire mesh 91 in the filtration tank 9 and dehydrated, and the treatment liquid mixture is filtered. The filtered treatment liquid can be circulated from the discharge port 9a on the inner bottom of the filtration tank 9 to the first floating separation tank 31 to be used again. In addition, the foreign material in the mesh wire net 91 is discarded outside.

  When the skimmer 52a moves over the scum box 53 and moves to a point where the skimmer detection switch 72 is located, the electromagnetic valve V is closed and the water level rises to the position of the liquid level F1 (see FIG. 3). When the water level further rises above the liquid level F1, the purified processing liquid flows down from the overflow weir 42a to the overflow tank 6, and the water level is maintained at the liquid level F1.

Then, as shown in FIG. 4, when the skimmer 52a turns and further moves away from the scum box 53 in the turning direction, and the operating rod 73 comes close to the skimmer detection switch 72, the skimmer detection switch 72 is turned on and the electromagnetic valve The valve V is opened, and the processing liquid flows from the discharge path 85 to the overflow tank 6 to lower the water level.
When the skimmer 52 a is turned away from the scum box 53 after turning on the skimmer detection switch 72, the water level of the processing liquid mixture is reduced to prevent the processing liquid mixture from flowing into the scum box 53. It is adjusted so as to descend to the bottom, and descends to the position of the liquid level F2. As a result, when the skimmer 52 is not working to drop the foreign matter into the scum box 53, the processing liquid mixture does not flow from the foreign matter removal weir 53b into the scum box 53. For this reason, the amount of the processing liquid mixture flowing in the scum box 53 can be reduced.

  Thus, when the skimmer 52 scrapes foreign matter, the electromagnetic valve V is opened to prevent the treatment liquid mixture from being discharged from the scum box 53, and the tank main body 42 to the overflow tank 6 from the discharge path 85. When the treatment liquid is flowed to lower the water level to the liquid level F2 and the foreign matter is discharged to the scum box 53, the electromagnetic valve V is closed to stop the treatment liquid from flowing out of the tank body 42 to the overflow tank 6 and to adjust the water level. The water level is adjusted so that the foreign matter is smoothly dropped into the scum box 53 by raising the liquid level F1.

  The second levitation separation device 4 performs an operation of discharging and removing foreign matter to the filtration tank 9 and an operation of sending the purified processing liquid to the overflow tank 6 during one cycle in which the skimmer arm 51 rotates once. The two skimmers 52a and 52b and the water level switching adjusting means 7 are performed twice. For this reason, since foreign substances can be efficiently discharged (discarded), the amount of processing liquid discarded as waste water can be greatly reduced.

According to the second levitating / separating device 4 of the present embodiment, the following effects can be obtained.
(1) Since the foreign matter removal weir 53b is formed lower than the upper end portion 53c of the opening 53a of the scum box 53, the foreign matter that has floated on the liquid surface F1 of the treatment liquid mixture starts from a position above the upper surface of the foreign matter removal weir 53b. Since it flows so as to fall into the scum box 53, the flow rate of the processing liquid mixture is increased, and it can be discharged smoothly.
(2) The lateral width of the skimmer 52 is longer than the lateral width of the foreign matter removal weir 53b. Thus, when the skimmer 52 passes over the foreign matter removal weir 53b, both sides of the skimmer 52 come into sliding contact with the front end portions of the side walls of the scum box 53 located on the left and right sides of the foreign matter removal weir 53b, thereby causing the foreign matter removal weir 53b. Therefore, the foreign matter is not crushed and adhered to the foreign matter removal weir 53b.
(3) When the foreign material is dropped into the scum box 53 by the skimmer 52, the valve of the electromagnetic valve V is closed by the skimmer detection switch 71, and the water level of the processing liquid mixture is raised to the liquid level F1 higher than the foreign matter removal weir 53b. Since it does not contact and adhere to the foreign matter removal weir 53b, it falls smoothly into the scum box 53.
(4) When the skimmer 52 passes over the foreign matter removal weir 53b, the water level of the treatment liquid mixture is adjusted so as to rise to the liquid level F1 above the foreign matter removal weir 53b, and the foreign matter floats in the treatment liquid mixture. Thus, the flow rate increases toward the inside of the scum box 53 while increasing the flow velocity, and flows into the opening 53a without contacting and adhering to the foreign matter removal weir 53b. Therefore, it is avoided that foreign matter lumps adhere to the upper surface of the foreign matter removal weir 53b by the lower end portion 52c of the skimmer 52.
(5) When the skimmer 52 is scraping foreign matter, the solenoid valve V is opened by the skimmer detection switch 72, the processing liquid is sent to the overflow tank 6 to lower the water level, and the processing liquid mixture is discharged from the scum box 53. Prevent it from being discharged. For this reason, while reducing the amount of the processing liquid discarded via the scum box 53, foreign substances can be reliably discharged and the processing liquid can be effectively reused.

  The present invention is not limited to the above-described embodiment, and various modifications and changes can be made within the scope of the technical idea. The present invention extends to these modifications and changes. Of course.

<< Modification >>
For example, in the above-described embodiment, the industrial water has been described as the treatment liquid. However, the treatment liquid is not particularly limited as long as it is a liquid in which foreign matter floats. On the other hand, the foreign substance may be liquid or solid, and is not particularly limited as long as it can float by air or the like even without buoyancy.
That is, the levitation separation apparatus and the levitation separation method of the present invention can be used for any apparatus that removes foreign matters floating on the liquid surface.

  Further, the skimmer detection switches 71 and 72 that are the water level switching adjusting means 7 are not limited to switches such as limit switches and proximity switches, and may be any one that detects the position of the skimmer 52. For example, the skimmer detection switches 71 and 72 may detect the skimmer 52 using a light emitting element and a light receiving element, or an encoder or a rotation switch for detecting the rotation angle of the skimmer arm 51.

  Further, the number of skimmers 52a and 52b is not limited to two, and may be appropriately changed according to the size, processing capability, processing liquid, and the like of the floating separation system A. The number of skimmers 52a and 52b may be, for example, one.

Claims (6)

A flotation separation tank in which processing liquid containing floating foreign substances is stored;
At least one skimmer that swirls along the liquid surface of the treatment liquid in the levitation separation tank and scrapes foreign substances floating on the liquid surface;
A scum box having an opening in the vicinity of the liquid level of the processing liquid and removing the foreign matter scraped by the skimmer from the liquid level,
Water level switching adjustment means is provided for lowering the level of the processing liquid when the turning skimmer is separated from the scum box in the turning direction, and for increasing the water level of the processing liquid when the skimmer is close to the scum box in the turning direction. Characteristic floating separator. The floating separation apparatus according to claim 1, wherein a weir lower than other portions is formed in the opening of the scum box on the side where the skimmer approaches. The water level switching adjusting means includes a discharge path for discharging the processing liquid from the floating separation tank to the outside,
At least one skimmer detection switch for detecting the position of the skimmer;
The levitation separation according to claim 1 or 2, further comprising: an electromagnetic valve provided on the discharge path and opening and closing the discharge path by a detection signal from the skimmer detection switch. apparatus. The lowered water level is set below the weir;
The floating separation apparatus according to claim 2 or 3, wherein the raised water level is set above the weir and below the upper end of the scum box. The floating separation device according to any one of claims 2 to 4, wherein a width in a longitudinal direction of the skimmer is longer than a width in a longitudinal direction of the weir. A flotation separation tank in which processing liquid containing floating foreign substances is stored;
At least one skimmer that swirls and scrapes the foreign matter floating on the surface of the treatment liquid;
A scum box that discharges the foreign matter squeezed by the skimmer to the outside of the floating separation tank, and a floating separation method by a floating separation device that removes the foreign matter that has floated on the processing liquid in the floating separation tank. And
When the turning skimmer moves away from the scum box in the turning direction, the water level of the processing liquid is lowered, and when the skimmer approaches the scum box in the turning direction, the water level of the processing liquid is raised to remove the foreign matter. A floating separation method characterized by the above.

Images