JP2015077587A - Pressure floatation type scrum separation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure floatation type scum separation apparatus which makes efficient scraping and dehydration of floating scum within a screw conveyor.SOLUTION: A floating separation tank 1 carrying out floating separation of sewage has a communication cylinder e for collecting scum guided by an oblique scum guide. On the upper side of the floating separation tank, a screw conveyor type scum discharge device 17 is fixed obliquely, and the scrum discharge apparatus has a casing in which a rectangular scum intake port 20 opened on the lower side of the inclination is communicated with the communication cylinder and fixed and which can discharges scum through a discharge port 35 opened on the upper side of the inclination, a scraping screw and dehydration means which is provided in the upper part of the casing and compresses scrum to remove moisture. The water level of sewage in the floating separation tank is set to be 1/2 of the diameter of the scraping screw high relative to the lower end part of the lower periphery on the upper side of the inclination of the scum intake port.

Description

  The present invention relates to a pressurized floating scum separation processing apparatus.

  When the collected scum-containing sewage is introduced into the levitation separation tank, the scum that has been levitated from the upper part by spouting the scum by urging the scum into the separation tank under reduced pressure with water in which air is dissolved by pressurization is introduced. The pressure levitation method for discharging is a known technique. As a technique related to such a technique, there is a technique disclosed in Patent Document 1.

Japanese Patent No. 4238297

The technique according to Patent Document 1 includes a scraper that scrapes the floated scum toward a scum discharge trough provided in a pressurized flotation concentration tank (flotation separation tank), an upper tank wall of the pressurized flotation concentration tank, and The scum discharged by the scraper having a curved surface formed so that the center position of the curve is located on the pressurized flotation concentration tank side and a rotating shaft and blades on the rotating shaft is discharged from the scum. A discharger provided near the curved surface for discharging to the trough, and a drive source having a function of rotating the rotation shaft of the discharger and adjusting the number of rotations thereof.
This scum pressurized levitation concentrator discharges the scum that has floated from the pressurized levitation concentration tank and allows the scum to be smoothly transported to a scum treatment facility far away. The means for discharging the scum consists of a scraper that is a chain with a scraping plate protruding from the outer periphery, and a discharger that rotates around the rotation axis with a scraping blade that moves along the curved surface. The scum is discharged to the scum discharge trough. Therefore, the floating scum contains sufficient moisture and is heavy and is discharged as it is. In addition, it is necessary to separate and remove moisture from the scum at the transport destination so that it can be used for a predetermined purpose.

Such a problem, that is, the scum that floats in the levitation separation tank is evacuated and discharged while being drained by the compression action, so that the post-discharge transportation can be performed with energy savings, and the separation process of scum and moisture at the transport destination can be reduced. The present applicant has previously proposed a pressure levitation type scum separation processing apparatus that can be simplified as much as possible (Japanese Patent Application No. 2012-185838).
One of the proposals is shown in FIGS.
In this pressurized levitation scum separation processing apparatus, reference numeral 1 denotes a levitation separation apparatus, which is provided with a levitation separation tank 2 which is open from the top and is a rectangular tank as viewed from above. The floating separation tank 2 has a tank body 3 and a separation water tank 5 via a partition wall 4, and the sewage 6 and the separation water 7 are at the same level H in the tank body 3 and the separation water tank 5. It can be stored.
8 is a communication pipe that connects the tank body 3 and the separation water tank 5, and the purified water having the filter 9 at the front and rear ends is introduced into the separation water tank 5 as the separation water 7. Reference numeral 10 denotes an overflow port for determining the water level H.
The separated water 7 in the separated water tank 5 is discharged to the outside through the overflow port 10, while the separated water 7 is pulled out from the bottom of the separated water tank 5 through the water supply pipe 11 by the operation of the water supply pump 12, which will be described later. It is introduced into the air dissolving device 45.

In the lower part of the tank body 3, a single supply pipe 14 or a plurality of supply pipes 14 provided with a plurality of nozzles 13 that also serve as pressure reducing valves are arranged so that the axial center is directed in the front-rear direction of the tank body 3. A screw conveyor 17 that is a scum discharge device is fixedly installed at an upper portion of the floating separation tank 2 including the tank body 3 and the separated water tank 5 in an inclined state of about 15 degrees.
The screw conveyor 17 includes a cylindrical casing 18 having an inner diameter of about 300 mm, and a lower end (tail side) in the inclination direction of the casing 18 is closed and the front side of the tank body 3 (left side in FIG. 1). On the other hand, one upper end (head side) in the inclined direction is also closed and fixed in a state of protruding to the rear side (right side in FIG. 1) of the floating separation tank 2.

Reference numeral 20 denotes a scum intake port, which is formed as a rectangular opening when viewed from below at a lower peripheral position away from the lower end of the casing 18 in the inclination direction, and the scum S that floats on the sewage 6. It is provided at a position suitable for taking in.
A screw shaft (or pipe) 22 passes through the center of the casing 18 and both ends thereof are rotatably supported by bearings, and a screw screw 23 is provided on the outer periphery of the screw shaft 22. The lifting screw 23 includes a screw main body 23a having a spiral plate, and the main body 23a is formed so that the upper end is about 70 cm away from the upper end of the casing 18.

A scooping ridge 23b that protrudes upward in the inclined direction is integrally provided as a spiral strip at the peripheral edge of the screw main body 23a that extends over a length L that is equal to or longer than the scum inlet 20 of the screw body 23a. Yes. Here, reference numeral 19 in FIGS. 1 to 3 denotes a scum guide. If the tank body 3 of the levitation separation tank 2 is left open so that the entire surface of the tank becomes a water surface and the sewage S is floated on the scum S, Incorporation of the scum S into the inlet 20 becomes passive.
Therefore, the scum guide 19 is provided so that the scum S floating along with the fine bubbles from the sewage 6 can be reliably and positively taken into the scum inlet 20.

  As shown in detail in FIG. 3, the scum guide 19 is formed in an inverted quadrangular pyramid shape by front and rear slope guides a and b and left and right slope guides c. It is fixed by touching. A square communication tube e is integrally provided at the center of the upper part of these four inclined guides a to c.

This communicating cylinder e is a vertically penetrating cylindrical part having left and right inclined plate-like opposing walls f and front and rear walls g, h. The opposing wall f is taken in the scum of the casing 18 of FIG. While being configured to be welded along the outer edge of the port 20, the front wall g of the front and rear is low, the rear h is high, and an arcuate fitting receiving groove i shorter than a semicircle on the upper side, By forming j, the outer edge portions of the front and rear of the scum inlet 20 are fitted into these fitting receiving grooves i and j and are welded.
In this way, the communication tube e is fitted to the outer edge of the scum inlet 20, so that the scum S that has risen is taken in without being clogged in the middle. 1 and 2 indicates the water surface of the sewage 6, and the water surface H is about the height of the groove bottom of the fitting receiving groove j of the communication tube e.

  Around the upper portion of the screw shaft 22 in the inclination direction, a compression receiving plate 26 constituting a receiving plate of the dehydrating means is provided. The compression receiving plate 26 is provided with a repulsion spring 33 so as to be freely advanced and retracted so that the scum S lifted up by the lifting screw 23 is compressed and then discharged from the discharge port 35. The discharge port 35 is provided with a chute 38 for dropping compressed scum into a container 37 on the transport conveyor 36. Reference numeral 40 in FIG. 1 denotes a driving source (driving means) which is a reduction motor, which rotates the screw shaft 22 in the direction of arrow R in FIG.

In FIG. 1, reference numeral 45 denotes a pressurized air dissolving apparatus including a plurality of air dissolving tanks 46. The water supply pipe 11 communicates with each air dissolution tank 46 through a parallel inlet pipe 47 and is connected to the supply pipe 14 through an outlet pipe 48 and a junction pipe 49 that integrates the outlet pipe 48. ing. Automatic valves 50 and 51 are provided on the entry side and the exit side of each air dissolution tank 46.
In the air dissolution tank 46, an air nozzle 53 is provided on the lower side of the air dissolution tank 46 so that the air dissolves in the internal water while the air circulates around the circulation partition plate 54. The air nozzle 53 is connected to air supply means such as a blower 56 or a compressor through each air pipe 55. Each of the air pipes 55 is provided with an air automatic valve 57 in a controllable manner.
Reference numeral 60 denotes a sewage receiving tank into which scum-containing sewage 61 collected from a sedimentation basin or a concentration tank is introduced. The receiving tank 60 and the junction pipe 49 are connected by a sewage supply pipe 62, and a sewage pump 63 is provided on the pipe.

The operation of this pressurized floating scum separation processing device will be described. With the inlet side automatic valve 50 (air or electrically operated) opened, the water supply pump 12 is operated to supply the separated water 7 in the separated water tank 5 to one air dissolving tank (pressurized water tank) 46. Next, the automatic valve 57 corresponding to one of the air dissolution tanks 46 is opened, and the blower 56 or the compressor is operated so that fine air is injected into the air dissolution tank 46 by the air nozzle 53. The fine air is dissolved in the internal water by increasing the pressure in 46 and using the internal water as a circulating flow.
Thereafter, when the sewage pump 63 is operated to send the scum-containing sewage 61 to the sewage supply pipe 62, the outlet automatic valve 51 corresponding to one of the air dissolution tanks 46 is opened at the same time, thereby dissolving the scum-containing sewage and air. The mixed pressurized water is mixed, and the mixture is fed into the tank body 3 of the floating separation tank 2 from the junction pipe 49 and the supply pipe 14 through the nozzles 13.

  The fine bubbles from the mixed water that has been sent in will float with scum. The floated scum S is taken into the scum inlet 20 while being smoothly guided by the slope guide by the scum guide 19, and is reliably lifted by the scooping function by the scooping ridge 23b attached to the lifting screw 23. become. The scum S which is scooped up and sent in the axial direction is dehydrated by the compression receiving plate 26 which is retracted while being repelled by the repulsion spring 33 from the back, and then passes through the chute 38 from the discharge port 35 to the container 37. To be discharged.

By the way, in the pressurized flotation type scum separation processing apparatus shown in FIG. 1 to FIG. 3, the water level H in the flotation separation tank 2 is defined to be constant according to the water level of the separation water tank 5, and the water level H is The level H is set to a level substantially corresponding to the height of the groove bottom of the rear fitting receiving groove j, and the level H is set to a low level with respect to the lifting screw 23, and as shown in the drawing, the lifting screw 23 It was set so shallow that only a part of the lower part of the scum sunk in the upper scum area.
Since the scum S is scraped up to a point beyond the point n that is the upper opening edge in the inclination direction of the scum intake port 20, the scum S is scraped in a proper manner since the scum S reaches the portion having the entire circumference of the casing 18. If it is a shallow water level H in which only a small portion around the bottom of the lifting screw 23 is submerged as described above, the surface of the lifting screw 23 scratches the scum S only around the bottom. Actually, the scum S only repeats the motion of being scraped in the communication tube e as indicated by the arrow X in FIG. 2, and as a result, the scum S generates a scraping phenomenon and the scum inlet 20 Therefore, there is a problem that it is difficult to rake up into the originally intended casing 18 and therefore cannot be raked up reliably and efficiently, and it is difficult to improve the subsequent pressing and dehydrating action. It has been a thing.

  The present invention is intended to solve the above-mentioned problem, and is a pressure floating type scum separation process in which the lifting is performed sufficiently reliably and efficiently in the screw conveyor of the floating scum and the dewatering action is also made efficient. An object is to provide an apparatus.

In order to achieve the above object, the invention described in claim 1 is a flotation separation tank provided with a flotation induction device for supplying collected scum-containing sewage with pressurized air, and clarified water communicating with the flotation separation tank. Is stored as separated water, and the stored water is at the same level as the water level in the levitation separation tank, and the effluent separation tank is levitated from the levitation induction device. In addition, a communicating cylinder for collecting the scum guided by the inclined scum guide is provided at the upper part of the tank, and a screw conveyor type scum discharging device has a lower end and a higher end at the upper side of the floating separation tank. The scum discharge device is connected and fixed so that the rectangular scum intake opening formed in the lower part of the lower side in the inclination direction is connected to the communication cylinder so as to communicate with the communication cylinder. And lean A casing capable of discharging the scum through a discharge opening opened around the lower side in the direction, a lifting screw provided in the casing so as to lift the scum upward and inclined, and an upper part of the casing. In the pressurized flotation type scum separation processing apparatus having a dewatering means for removing moisture by compressing the scum that is provided and scraped, the sewage in the flotation separation tank is inclined at the scum intake port. The water surface is set to a level higher than ½ of the screw diameter D of the lifting screw with reference to the lower lower end portion in the upper direction.
The invention according to claim 2 is the one according to claim 1, wherein the screw conveyor of the screw conveyor has a longer screw portion provided in a length portion corresponding to the scum intake port than the other screw portions. It is formed as a pitch.
According to a third aspect of the present invention, in the first or second aspect of the present invention, the levitation guidance device is a levitation that stands vertically from the bottom of the levitation separation tank so that the upper end opening faces the scum intake port. An induction pipe, a pipe for introducing sewage from the outside into the levitation induction pipe, and an air diffuser for supplying air from an air supply source into the levitation induction pipe. The air diffuser main body at the tip is provided, and the supply pipe and the air diffuser main body can be detached as a unit through a desorption guide pipe that connects the floating separation tank and the floating guide pipe.

As described above, the invention described in claim 1 is a flotation separation tank provided with a flotation induction device that supplies collected scum-containing sewage with pressurized air, and separates the clarified water in communication with the flotation separation tank. A separation water tank that stores water as a water level that is the same level as the water level in the floating separation tank and that allows the drainage of the water, and the floating separation tank floats from the floating guide device. A communicating cylinder for collecting the scum guided by the inclined scum guide is provided at the upper part of the tank, and a screw conveyor type scum discharge device is inclined above the floating separation tank with one end lowered and the other raised. The scum discharge device is cylindrically connected and fixed so that a rectangular scum intake opening formed in a lower part around the lower side in the inclination direction is connected to the communication cylinder so as to communicate with the communication cylinder. Inclination direction A casing capable of discharging the scum through a discharge opening opened around the lower side of the side, a scraping screw installed in the casing so as to lift the scum upward and inclined, and provided in the upper part of the casing In the pressurized flotation type scum separation processing apparatus having a dewatering means for removing the moisture by compressing the scum that has been swept up, the sewage in the flotation separation tank is in the direction of inclination of the scum inlet Since the water surface is set to a level that is higher than 1/2 of the screw diameter D of the lifting screw with the lower lower end of the upper part as a reference, it is possible to sufficiently lift up the screw in the screw conveyor of the floating scum. In addition, it is possible to provide a pressurized flotation type scum separation processing apparatus that is efficiently performed and the dehydrating action is also improved.
The invention according to claim 2 is the one according to claim 1, wherein the screw conveyor of the screw conveyor has a longer screw portion provided in a length portion corresponding to the scum intake port than the other screw portions. Since it is formed as a pitch, it is possible to provide a pressure levitation scum separation processing device that is sufficiently reliably and efficiently scraped in the screw conveyor of the levitation scum and has an improved dewatering effect. .
According to a third aspect of the present invention, in the first or second aspect of the present invention, the levitation guidance device is a levitation that stands vertically from the bottom of the levitation separation tank so that the upper end opening faces the scum intake port. An induction pipe, a pipe for introducing sewage from the outside into the levitation induction pipe, and an air diffuser for supplying air from an air supply source into the levitation induction pipe. The air diffuser main body is provided with a tip diffuser main body and the supply pipe and the air diffuser main body can be detached as a single unit through a desorption guide pipe that connects the floating separation tank and the floating guide pipe. Can be kept in a state where a normal aeration function can always be performed by regular maintenance and inspection, and as a result, the scum can be lifted effectively and the scum can be lifted sufficiently reliably and efficiently. The pressurized flotation above equation scum separation processing apparatus can be provided.

  FIG. 6 is a schematic cross-sectional view showing an example of a conventional pressurized floating scum separation processing apparatus.   Sectional drawing which expands and shows the A section of FIG.   The perspective view which shows the detail of the scum guide of FIG.   The cross-sectional schematic diagram which shows one Embodiment of the pressurization floating type scum separation processing apparatus of this invention.   The principal part expanded sectional view of the apparatus of FIG.   The expanded sectional view which shows other embodiment which provided the pressurization type air dissolution apparatus outside the apparatus.   Sectional drawing which shows embodiment which set the screw conveyor to the angle of 30 degree | times with respect to the horizontal.   The cross-sectional view which shows other embodiment about a scum intake and a communicating cylinder.   The enlarged view of the M section of FIG.   XX expanded sectional view of FIG.   XI-XI line expanded sectional view of FIG.   The cross-sectional schematic diagram of the floating separation apparatus which shows other embodiment.   The principal part enlarged view of FIG.

  FIG. 4 shows an embodiment of the present invention. In this embodiment, the levitating / separating apparatus 1 is the same as the conventional example of FIG. 1 except for a part which is a main part of the present invention. The tank body 3 of the levitation separator 1 is detachably mounted on a gantry 66 having a certain height (for example, around 2 m) from the installation base. The gantry 66 in FIG. 4 shows four leg bases 67 and a mounting base 68 having a rectangular frame shape.

  On the bottom wall 70 of the tank body 3, a levitation guide pipe 71, which is a main part of the levitation guidance device, is detachably mounted and fixed so as to correspond concentrically below the scum inlet 20. The levitation guide pipe 71 is a round cylinder having a diameter of about 350 mm, but may be a triangle cylinder or a square cylinder, and an upper end opening 73 having an upper throttle portion 72 is concentric with the scum inlet 20 from below. Standing vertically so that it faces the shape.

  A sewage supply pipe 62 whose tip is an elbow-shaped trumpet type is connected to the center of the lower part of the levitation guide pipe 71 through the levitation separation tank 2. Reference numeral 75 denotes a guide cylinder, which is a cylindrical body having a trumpet shape on the top and bottom. If sediments are generated by providing them, they can be guided downward and discharged appropriately through an automatic valve.

  Reference numeral 77 denotes an air diffuser, and the air diffuser 77 includes an air diffuser main body 78 positioned at the lower center of the levitation guide pipe 71. The air diffuser main body 78 is upward from below as shown in FIG. A detachable perforated plate 79 for ejecting compressed air and a casing 80 are provided. Reference numeral 82 denotes a desorption guide pipe, which is a round (or square) pipe having a front and rear penetration and a larger inner diameter than the diffuser main body 78, one end communicating with the levitation guide pipe 71 and the other end outside the levitation separation tank 2. It is fixed horizontally so as to communicate with each other through a flange.

  Reference numeral 83 denotes a supply pipe, which is a pipe for introducing air from the air supply source 56 into the levitation induction pipe 71 via the air diffuser 77, and around the air supply pipe 83, FIGS. As shown in FIG. 4, in addition to the front seal plate 84 and the rear closing plate 85 for preventing backflow, there is provided a steady plate 86 capable of sliding back and forth in the attachment / detachment guide pipe 82, and at the tip of the air supply pipe 83 is scattered in a continuous manner. A gas device body 78 is provided. The front seal plate 84 shuts off the inside and outside of the desorption guide pipe 82 via seal packing (not shown), but can also advance and retreat as it is along the desorption guide pipe 82. The rear closing plate 85 is attached to a flange at the outer end of the attachment / detachment guide pipe 82 in a watertight manner via a fastener, and can be removed as necessary.

  When the fastener is removed and the rear closing plate 85 is removed from the attachment / detachment guide pipe 82 and pulled outward, the diffuser main body 78 can pass through the attachment / detachment guide pipe 82, and at that time, the steady plate 86 and the front seal The plate 84 slides into the attachment / detachment guide pipe 82, so that the diffuser body 78 is smoothly taken out while being supported concentrically without dropping. As indicated by phantom lines in FIG. 9, members and parts that are likely to be clogged with foreign substances such as the air supply pipe 83 and the porous plate 79 of the air diffuser 77 can be easily inspected and serviced or replaced. The air diffuser 77 that has been inspected and maintained can be easily restored to its original state by inserting the front seal plate 84 into the attachment / detachment guide pipe 82 and sliding it, and the front seal plate 84 and the rear closing plate 85. As a result of being watertight with respect to the desorption guide pipe 82, it is possible to obtain an air diffuser with high sealing performance.

  In FIG. 4, sewage and air dissolution / levitation are performed in the levitation guide pipe 71. However, as shown in FIG. 5, scum-containing sewage and supersaturated fine air mixed water are combined outside the tank 2. There may be a case where it is configured to be introduced into the levitation guide pipe 71 in the tank 2 later. That is, 88 is a pressurized air dissolving device, and an air refining unit 90 and a spring-biased on-off valve 91 are installed in the main body of the air dissolving tank 89 so as to be able to be attached / detached and replaced. An air supply source 92 made of a compressor is connected, and a water supply pipe 11 from the separation water tank 5 is connected to communicate with the downstream side of the unit 90. The supersaturated fine air-mixed water produced by the device 88 is combined with the scum-containing sewage 62 and introduced into the levitation guide pipe 82 to levitate and separate the scum S.

On the other hand, as shown in FIG. 4, the separation water tank 5 has a semicircular concave notch 95 at the front and back of the upper end. The screw conveyor 17 is stabilized by connecting and fixing.
In this case, the separation water tank 5 is provided with a rotary operation handle 98 that can be locked at an appropriate rotation angle by attaching an elbow overflow pipe 97 to a rotary support 96 fixed to the side wall so as to be rotatable. 98 is configured to be adjustable up and down, whereby the water level in the separation water tank 5 can be freely changed.

The desired water level in this case is H + A based on the water level H in FIG. H indicates the height of the lower lower end of the scum intake port 20 in the inclination direction, and A is higher than ½ of the screw diameter D of the lifting screw 23. In this embodiment, the screw diameter The dimension (height) is substantially the same as D.
Therefore, the water level in the casing 18 on the floating separation tank 2 is also adjusted to be the same as H + A. Here, as a preferable condition for the raking, A is set to be higher than ½ of the screw diameter D as shown in the level line of FIG. If the water level is set to about D / 2 or more vertically upward with respect to the lower lower end n of the scum intake port 20 above the inclination direction, the scum S also rises to the same level, and then the n point is set. Since the scum S also floats and accumulates in the Q range in the front and rear of the tilt direction at the boundary, the scum S of these Q parts is above the scum inlet 20 of the casing 18 when the screw parts q1 and q2 rotate. It is surely lifted up in the Y direction in the cylinder. If the fried food is made reliable and efficient, the subsequent dewatering action is effectively performed.

In particular, as shown by H + A in FIGS. 4 and 5, if the water level is set to a height approximately the same as the screw diameter D, the scum S rises to a higher level and is higher than n points. The levitation scum S is surrounded by the casing 18 so that the levitation scum S is not only more reliably and efficiently lifted up as indicated by the arrow Y, but also scum below the n point in the inclination direction. Since a large amount of S floats and accumulates in the cylinder as a whole, the scum S portion lifts up the n or more scums S, so that the entire rake is surely and efficient. The above-mentioned A does not have to be increased as much as possible. Since the dewatering function cannot be secured when the dehydrating means is submerged, the water level should be sufficiently lower than the compression receiving plate 26, which is the lower end of the dehydrating means. Should be set.
In addition, the water level can be made constant by opening a fixed-position opening type overflow opening as shown in FIG.
The scooping ridge 23b can be omitted due to the improvement of the scooping function of the screw itself.

FIG. 7 shows another embodiment, and this embodiment shows an example in which the screw conveyor 17 rises to 30 ° with respect to the horizontal line. Has the advantage of improving.
FIG. 8 shows another embodiment. In this embodiment, the semi-circular portion of the casing 18 is cut out to form a scum intake port 20 in a wide angle range, so that the scum S can be more easily increased in the screw conveyor. It was designed to enter. The communication cylinder e rises up to both side heights of the casing 18 according to the shape of the scum inlet 20 and is connected.

  12 and 13 show another embodiment. In the conventional pressurized levitation type scum separation processing apparatus, as shown in FIG. 2, the scum S can be swept beyond the scum intake port 20 beyond the inclination of the port 20, and then the casing 18 is turned around. However, if the surface of the cradle screw 23 is all about 15 °, the surface of the cradle screw 23 is The scum S swept up by the surface only repeats the movement of scraping into the communicating tube e that is obliquely sideways as indicated by the arrow X in FIG. 2, and as a result, the scum S is spilled and the scum intake port It is difficult to scrape over the opening edge of 20 to the entire cylindrical part of the casing 18 at the upper side of the slope. Therefore, the scraping cannot be reliably and efficiently performed, and the subsequent pressing and dewatering can be performed as prescribed. There is a problem that Kunar.

  Therefore, in this embodiment, the length B in the inclination direction of the scum inlet 20 is 55 mm in the drawing, and the long pitch screw main body 23c is slightly longer than the portion corresponding to the dimension B of the scum inlet 20. The remaining short pitch screw main body 23a is connected to each other in a spiral shape to form a screw main body. The short pitch screw body 23a has a size of 1/2 × P2 (1/2 pitch) of 12 mm in the drawing, while the long pitch screw body 23c has a size of 1/2 × P1 (1/2 pitch) of 5 times that in the drawing. It is set to 6 mm.

  The long pitch screw main body 23c is provided with scooping ridges 23b so as to increase the filing effect. As shown in FIG. 13, the long pitch screw body 23c has a 45 ° angle between the outer peripheral tangent line of its blades and the surface crossing the screw conveyor 17 so that the longer pitch portion can be scummed as described above. Since the rotation can be swung freely corresponding to the inlet 20, the scum S rising from the scum inlet 20 is cut, and the Y direction (axial direction) as shown in FIG. 13 instead of the X direction as shown in FIG. In this way, it is possible to surely and efficiently carry out the filing and to effectively perform the subsequent dehydration. Further, the long pitch screw body 23c has several times more scum feed per rotation than the short pitch screw body 23a, and as a result, more scum is fed to the short pitch screw body 23a side, resulting in dehydration (compression). ) The action becomes more active.

The water level can be obtained even if it is shallow as shown in FIG. 2H. However, when the water level is intended to obtain the effect more reliably, it is as high as H + A in FIG. Then, the entire long pitch screw main body 23c can be submerged, and the main body 23c can be submerged in the scum S region having a high level to ensure the lifting. When the screw diameter is D, A can be in the range of 0 to D / 2, or can be in the range of D / 2 to D / 2. However, in this embodiment, the water level is set and secured within the range of Q in FIG. 13, that is, at least about D / 2 from the point n, so that the scum S is taken in as indicated by the arrow Y without scraping. It is configured so as to be surely lifted from the mouth 20 into the entire cylindrical portion of the casing 18. By raising A to about the screw diameter D, it becomes possible to more reliably fry up.
In FIG. 12, 100 is a vertically long overflow port, 101 is a height adjusting weir, and 102 is a weir guide. The angle of the screw may be in the range of 40 to 50 °.

  DESCRIPTION OF SYMBOLS 1 ... Levitation separation apparatus 2 ... Levitation separation tank 3 ... Tank main body 5 ... Separation water tank 17 ... Screw conveyor 18 ... Casing 26, 33 ... Dehydration means 20 ... Scum intake port 22 ... Screw shaft 23 ... Lifting screw 35 ... Discharge port 40: Drive source (drive means).

Claims (3)

  A floating separation tank equipped with a levitation induction device that supplies collected scum-containing sewage with pressurized air, and stores clarified water as separated water in communication with the floating separation tank, and the stored water is stored in the floating separation tank. A separation water tank that has the same water level as that of the water level and can also be drained, and the floating separation tank collects the scum that has been guided by the inclined scum guide while floating from the levitation guide device. A communicating cylinder is provided at the top of the tank, and on the upper side of the floating separation tank, a screw conveyor type scum discharge device is fixed in an inclined shape with its one end lowered and the other end raised, and the scum discharge device is A rectangular scum intake port that is formed in a cylindrical shape in the lower part on the lower side in the tilt direction is connected and fixed so as to communicate with the communication tube, and is formed through a discharge port that is provided in the lower part on the upper side in the tilt direction. A casing capable of discharging a vacuum, a scraping screw provided in the casing so as to scrape up the scum, and a scum that is lifted up in the upper part of the casing. In the pressurized flotation scum separation processing apparatus having a dewatering means for compressing and removing water, the sewage in the flotation separation tank is scraped with reference to the lower lower end portion of the scum intake port at the upper part in the inclination direction. A pressure levitation scum separation treatment apparatus characterized in that a level higher than ½ of a screw diameter D of a lifting screw is set as a water surface.   2. The flotation screw of a screw conveyor according to claim 1, wherein the screw portion provided on the length portion corresponding to the scum intake port is formed with a longer pitch than the other screw portions. Type scum separation processing device.   The levitation guidance device according to claim 1 or 2, wherein the levitation guidance device is configured to cause a levitation guide pipe standing vertically from a bottom of the levitation separation tank so that an upper end opening faces the scum intake port, and sewage from the outside. A pipe to be introduced into the levitation induction pipe and an air diffuser for supplying air from the air supply source into the levitation induction pipe. The air diffuser includes a supply pipe and an air diffuser main body at the tip thereof. In addition, the pressure levitation type scum separation processing apparatus is configured such that the supply pipe and the diffuser main body are detachable as a unit through a detachment guide pipe that connects the levitation separation tank and the levitation guide pipe.