JP6183525B1 - Coagulation sedimentation equipment - Google Patents

Abstract

The present invention provides an agglomeration sedimentation apparatus that can be easily carried on a truck or the like.
An inorganic flocculant, a pH adjuster and a cationic polymer flocculant are added to an agglomeration reaction tank 11 and stirred with a stirrer 15 to form an agglutination reaction liquid. The agglomeration reaction liquid flows out to the advection tray 17, and after the anionic polymer flocculant is added, is supplied tangentially into the enlarged diameter portion 18 </ b> A of the center well 18, toward the downstream side in the rotational direction of the distributor 19. leak. The treated water that has passed through the sludge blanket S rises in the sedimentation tank 12, flows into the trough 25 from the V notch 25 a, and is taken out of the coagulating sedimentation apparatus 1 through the extraction pipe 26. The sludge is discharged from the sludge receiving tank 13 to the outlet 30 by the rake plate 35.
[Selection] Figure 2

Description

  The present invention relates to a coagulating sedimentation apparatus that coagulates and separates fine suspended substances and the like from water to be treated.

  It is known that an inorganic flocculant is added to raw water (treated water) such as factory waste water and sewage, and then an anionic polymer flocculant and a cationic polymer flocculant are added to perform solid-liquid separation. Patent Document 1 discloses a line mixing device for adding an inorganic flocculant, a cationic polymer flocculant and an anionic polymer flocculant to raw water containing fine SS, and a structure provided on the downstream side of the line mixing device. A water treatment apparatus comprising a granulated coagulation sedimentation tank is disclosed.

  In Patent Document 2, a first stirring tank for adding and stirring an inorganic flocculant, a second stirring tank for adding and stirring a sedimentation accelerator and a polymer flocculant, and adding and stirring a polymer flocculant A coagulating sedimentation apparatus in which a third stirring tank, a floc-forming tank, and a precipitation tank are integrated is described.

International Publication No. 2014/038537 JP 2014-237123 A

  It is an object of the present invention to provide an agglomeration precipitation apparatus that can be easily carried on a truck or the like.

  The coagulation sedimentation apparatus of the present invention includes a tank body having a rectangular shape in plan view, a coagulation reaction tank and a precipitation tank formed by partitioning the tank body by a partition plate, and an overflow of sludge with respect to the sedimentation tank. And a sludge receiving tank adjacent to each other through a plate. The tank body has a width of 2.2 m or less, a length of 5.6 m or less, and a height of 2.6 m or less.

  In the coagulation sedimentation apparatus according to an aspect of the present invention, a center well is provided in the precipitation tank, and a transfer member that allows the aggregation reaction liquid in the aggregation reaction tank to flow into the center well is provided.

  In the coagulation / sedimentation apparatus according to one aspect of the present invention, a distributor extends in a radial direction from a lower portion of the center well, and a drive device that rotates the center well about an axis is provided.

  In the coagulation sedimentation apparatus according to one aspect of the present invention, a sludge removal outlet for taking out the sludge in the sludge receiving tank is provided on the wall surface of the tank body, and the sludge removal along the bottom surface in the sludge receiving tank. A rake plate is provided that moves toward the outlet.

  In the coagulation sedimentation apparatus according to one aspect of the present invention, the rake plate is attached to a chain that is driven endlessly, and the chain is disposed on the forward side along the bottom surface of the sludge receiving tank and above the forward side. Between the driving side sprocket wheel and the driven side sprocket wheel so that the upper end of the rake plate when the rake plate is moved back by the chain is above the overflow plate. Located below the edge.

  Since the tank body of the present invention has a rectangular shape in plan view that is large enough to be mounted on a 4t truck, it can be easily transported. Further, by previously integrating a stirrer, a center well, a distributor, and other attached equipment in the production factory of the coagulation sedimentation apparatus, installation work of the coagulation sedimentation apparatus becomes remarkably easy.

  In addition, by installing a rake device in the sludge receiving tank, the precipitated sludge can be smoothly taken out from the sludge outlet. By providing this rake device with a rake plate that moves along the bottom surface of the sludge receiving tank, the sludge can be scraped to the outlet side from almost the entire bottom surface of the sludge receiving tank. If the rake plate moves forward along the bottom of the sludge receiving tank toward the outlet and moves upside down from the chain on the return side of the chain, it overflows the upper edge of the rake plate during return. By making it lower than the upper edge of the flow plate, the sludge blanket in the settling tank is not disturbed.

It is a perspective view of the tank of the coagulation sedimentation apparatus concerning an embodiment. It is a top view of the coagulation sedimentation apparatus concerning an embodiment. It is the III-III sectional view taken on the line of FIG. It is the IV-IV sectional view taken on the line of FIG. It is a top view of the coagulation sedimentation apparatus concerning another embodiment.

  Hereinafter, embodiments will be described with reference to the drawings. 1 to 4 show an agglomeration precipitation apparatus 1 according to a first embodiment of the present invention.

  The coagulating sedimentation apparatus 1 includes a tank body 2 having a pair of short walls 2a, 2c and a pair of long walls 2b, 2d and having a rectangular shape (as a whole, a rectangular parallelepiped shape) in plan view, and the tank body 2 is provided along the longitudinal direction of the tank body 2 between the partition plates 3, 4 provided in the short direction (width direction) and the partition plate 4 and the short wall 2 c of the tank body 2. It has an overflow plate 5 and the like. The tank body 2 has a width of 2.2 m or less, a length of 5.6 m or less, and a height of 2.6 m or less so that it can be mounted on a 4t track. The width of the tank body 2 is preferably 1.0 to 2.2 m, particularly 1.5 to 2.2 m. The length of the tank body 2 is preferably 1.0 to 5.6 m, particularly 1.5 to 5.6 m. The height of the tank body 2 is preferably 1.0 to 2.6 m, particularly 1.5 to 2.6 m.

  The partition plates 3 and 4 stand up from the bottom surface 2 e of the tank body 2 to the vicinity of the upper edge of the tank body 2. The partition plates 3 and 4 are connected to the longitudinal walls 2 b and 2 d of the tank body 2. A machine room 10 is provided between the partition plate 3 and the short wall 2a of the tank body 2, and a control panel, a pump, and other devices are installed therein.

Between the partition plates 3 and 4 is an agglomeration reaction tank 11, and between the partition plate 4 and the short wall 2 c of the tank body 2 is a sedimentation tank 12 and a sludge receiving tank 13. The settling tank 12 and the sludge receiving tank 13 are partitioned by the overflow plate 5. The ratio _V 1 / _{V 2} between the volume _{V 2} of the volume _{V 1} and the precipitation tank 12 of the coagulation reaction tank 11 is preferably about 0.9 to 1.2.

  In the agglomeration reaction tank 11, an inorganic flocculant and a cationic polymer flocculant can be added by a chemical injection device (not shown), and a stirrer 15 for agitating the liquid in the tank is provided. .

  An agglomeration reaction liquid outlet 16 is provided at the upper part of the partition plate 4, and an advection tray (which may be a pipe) 17 is connected to the upper part of the partition plate 4 as a transfer member so as to be connected to the outlet 16. ing. The advection tray 17 is provided with a chemical injection device (not shown) for adding an anionic polymer flocculant.

  It is preferable that the sedimentation tank 12 has a substantially square shape in plan view. A center well 18 is provided in the center of the settling tank 12. The center well 18 has a cylindrical shape and is provided with an enlarged diameter portion 18A in the upper part. The tip of the advection tray 17 is arranged so that the agglomeration reaction liquid flows out in a substantially tangential direction in the enlarged diameter portion 18A.

  A distributor 19 is provided below the center well 18. The distributor 19 is formed of a tubular body extending in the radial direction from the center well 18, and an outlet 19a is provided toward the downstream side in the rotational direction. The distributor 19 is provided with a rake 19b facing downward, but may be omitted.

  The center well 18 is supported on the tank bottom surface 2e by the shaft support portion 20, and is rotatable about the axis.

  The upper part of the center well 18 is connected to the rotation shaft 22 a of the drive device 22 via the bracket 21. A stirring blade 23 is attached near the middle of the center well 18 in the vertical direction.

  A trough 25 for taking out supernatant water (treated water) is provided in the upper part of the settling tank 12. The trough 25 has a U-shaped vertical cross section, and is configured such that the supernatant water in the settling tank 12 flows into the trough 25 through a V-notch 25a provided at the upper edge.

  The trough 25 is provided in a surrounding frame shape so as to surround the center well 18. The trough 25 extends along the long wall 2b and the short wall 2c of the tank body 2 and the partition plate 4 with a predetermined interval therebetween. In these portions, a V notch 25a is provided on the upper edge of the trough 25 only on the center well 18 side (inside the surrounding frame).

  Further, the trough 25 extends in the longitudinal direction of the tank body 2 above the overflow plate 5 on the center well 18 side. In this portion, V notches 25a are provided on both the upper edge of the trough 25 on the center well 18 side (inside the surrounding frame) and on the sludge receiving tank 13 side (outside the surrounding frame).

  A treated water extraction pipe 26 is connected to the trough 25. The V-notch 25 a of the trough 25 becomes the liquid level in the precipitation tank 12. In this embodiment, the enlarged diameter portion 18A is located above the liquid level. However, the enlarged diameter portion 18A may be disposed in contact with the liquid surface.

  At the bottom of the sedimentation tank 12, at the corner of the intersection of the long wall 2 b and the short wall 2 c of the tank body 2, the lower part of the partition plate 4 and the overflow plate 5, and the bottom surface 2 e of the tank body 2. An inclined plate 28 is provided so as to incline downward in the axial direction, and is configured to eliminate a stagnation area of liquid or sludge.

  The overflow plate 5 has a height that rises from the bottom surface 2 e to a height of about 50 to 80% of the liquid level in the sedimentation tank 12. A sludge blanket S is formed in the settling tank 12 up to the height of the upper edge of the overflow plate 5.

  The amount of the sludge blanket S formed in the settling tank 12 increases with the treatment, but if the level of the sludge blanket S (sludge interface) exceeds the height of the overflow plate 5, the sludge (pellet) of the sludge blanket S Overflows the overflow plate 5 and falls into the sludge receiving tank 13. An inclined plate 29 is provided on the bottom surface in the sludge receiving tank 13. The inclined plate 29 is installed so as to have a downward gradient from the longitudinal wall 2d toward the overflow plate 5.

  As shown in FIG. 1, a sludge outlet 30 for taking out the sludge (pellet) in the sludge receiving tank 13 is provided at the lower part of the short wall 2c. In the sludge receiving tank 13, a rake device 31 for moving sludge (pellets) toward the sludge outlet 30 is provided.

  The rake device 31 includes a driving side sprocket wheel 32 and a driven side sprocket wheel 33 provided on the overflow plate 5 and the longitudinal wall 2d, respectively, and a chain 34 that spans between the sprocket wheels 32 and 33 and rotates endlessly. And a rake plate 35 that is fixed to the chain 34 across the chains 34, 34, and a drive device 36 for driving the drive-side sprocket wheel 32. Two or more rake plates 35 are preferably provided.

  The rake plate 35 moves (forward movement) from the partition plate 4 side toward the sludge outlet 30 side along the inclined plate 29, so that the sludge (pellet) at the bottom in the sludge receiving tank 13 is transferred to the sludge outlet 30. Raked.

  When the rake plate 35 moves forward from the partition plate 4 side to the take-out port 30 side, the rake plate 35 is in a posture of hanging from the chain 34. When the rake plate 35 moves backward from the outlet 30 toward the partition plate 4, the rake plate 35 stands up from the chain 34. The upper end of the standing rake plate 35 is preferably located lower than the upper edge of the overflow plate 5 by 50 cm or more. Further, the lower side portion of the rake plate 35 in the suspended state is at an angle along the surface of the inclined plate 29.

  In the coagulation precipitation apparatus 1 configured in this way, raw water is introduced into the coagulation reaction tank 11 through a pipe (not shown), an inorganic coagulant, a pH adjuster, and a cationic polymer coagulant are added. Stirred to become an agglutination reaction solution.

  The agglomeration reaction liquid flows out to the advection tray 17 and, after anionic polymer flocculant is added, is supplied in a tangential direction into the enlarged diameter portion 18A of the center well 18 and swivels in the enlarged diameter portion 18A. It flows into the well 18, flows down in the center well 18, flows into the distributor 19, and flows out from the outlet 19 a toward the downstream side in the rotational direction of the distributor 19.

  When the feed well 18 does not have the enlarged diameter portion 18A and the aggregating treatment liquid is directly introduced into the feed well 18, the aggregating treatment liquid is foamed (air in the atmosphere is mixed), and bubbles are precipitated. There is a risk of mixing into the tank 12. In the present invention, since the sedimentation tank 12 is relatively small, there is a high possibility that the sludge in the sludge blanket S will be rolled up if any air bubbles are mixed. Therefore, the feed well 18 is provided with an enlarged diameter portion 18A, and the agglomeration treatment liquid is caused to flow tangentially into the enlarged diameter portion 18A and swirled. Air bubbles are not mixed.

  The distributor 19 and the stirring blade 23 are slowly rotated by the driving device 22, whereby the inside of the sedimentation tank 12 is slowly stirred, and the generation and growth of sludge (pellets) in the flocs floc and sludge blanket S is promoted. A stable sludge blanket S is generated. The rotation speed of the distributor 19 is preferably about 0.6 to 1.4 rpm.

  While the flocculation reaction liquid passes through the sludge blanket S, the flocculation floc adheres to the sludge (pellets) in the sludge blanket and becomes clear treated water. The clear treated water that has passed through the sludge blanket S rises in the sedimentation tank 12, flows into the trough 25 from the V notch 25a, and is taken out of the coagulating sedimentation apparatus 1 through the extraction pipe 26.

  In this embodiment, in the trough 25 on the overflow plate 5 side, V notches 25a are provided on both sides of the center side of the sedimentation tank 12 and the sludge receiving tank 13 side, and other than the overflow plate 5 side. In the trough 25, the V notch 25a is provided only in the side part of the sedimentation tank 12 center side. Thereby, the upward flow LV in the settling tank 12 can be set large. That is, by providing a V notch on the sludge receiving tank 13 side of the trough on the overflow plate 5 side, a part of the liquid in the settling tank 12 flows toward the sludge receiving tank 13 to form an upward flow, thereby forming a V notch. As a result, the upward flow LV in the vicinity of the trough is slightly smaller than the upward flow LV in the settling tank 12, and it becomes easy to obtain treated water with stable water quality.

  In this embodiment, since the entire enlarged diameter portion 18A is arranged higher than the water surface in the precipitation tank 12, compared to the case where the lower portion of the enlarged diameter portion 18A is arranged below the water surface. The upward flow LV in the settling tank 12 can be set large.

With the above configuration, the upward flow LV in the settling tank 12 can be set high to 5 to 20 m / hr, particularly about 8 to 15 m / hr.
When the sludge (pellet) interface height of the sludge blanket S becomes higher than the overflow plate 5, the sludge (pellet) overflows the overflow plate 5 and flows into the sludge receiving tank 13, and settles at the bottom of the sludge receiving tank 13. To do. This sludge (pellet) is scraped to the outlet 30 side by the rake plate 35 and is taken out of the coagulating sedimentation apparatus 1 from the outlet 30 via an extraction pipe and a sludge pump (not shown). This sludge pump is ON / OFF controlled by an interface meter or timer that detects the sludge interface height in the sludge receiving tank 13.

  The tank body 2 of the coagulating sedimentation apparatus 1 is easy to carry because it has a rectangular shape in plan view that is large enough to be mounted on a 4t track. Further, by previously integrating a stirrer, a center well, a distributor, and other attached equipment in the production factory, the installation work of the coagulating sedimentation apparatus 1 is remarkably facilitated.

  Moreover, the rake apparatus 31 is installed in the sludge receiving tank 13, and the settled sludge (pellet) is taken out from the sludge extraction outlet 30 smoothly. The rake device 31 includes a rake plate 35 that moves along the inclined plate 29, and can remove sludge (pellet) from almost the entire bottom surface of the sludge receiving tank 13 toward the outlet 30. The rake plate 35 moves forward along the inclined plate 29 toward the outlet 30, and moves upright from the chains 34, 34 on the return side of the chain 34. Since the upper edge of the rake plate 35 passes sufficiently lower than the upper edge of the overflow plate 5 during the backward movement, the sludge blanket S in the settling tank 12 is not disturbed.

In the above embodiment, the settling tank 12 and the sludge receiving tank 13 are arranged adjacent to each other in the short direction of the tank body 2, but the sludge receiving tank 13 is the settling tank as in the coagulating sedimentation apparatus 1 ′ of FIG. You may arrange | position at the 12 short wall 2c side. The other structure of the coagulation precipitation apparatus 1 'of FIG. 5 is the same as that of the coagulation precipitation apparatus of FIGS. 1-4, and the same code | symbol has shown the identical part.
Moreover, in the said embodiment, although the inside of an integrated tank is divided with the partition plate, for example, the machine room 10, the aggregation reaction tank 11, and the sedimentation tank 12 are each manufactured independently, You may comprise the integral tank 2 by connecting a tank via a wall surface. In this case, the partition plate 3 corresponds to each wall surface sandwiched between the machine room 10 and the aggregation reaction tank 11, and the partition plate 4 corresponds to each wall surface sandwiched between the aggregation reaction tank 11 and the precipitation tank 12.

[Flocculant]
The inorganic flocculant is preferably one that forms hydroxide such as PAC, polyiron (polyferric sulfate), salt iron (ferric chloride), or sulfate band. In fluorine-containing water and phosphoric acid-containing water, calcium compounds such as slaked lime can also be used as the inorganic flocculant. The amount of the inorganic flocculant added is preferably 20 to 2000 mg / L, particularly about 50 to 1500 mg / L.

  The cationic polymer (cationic polymer flocculant) is preferably an acrylamide type, and the cationic group ratio is preferably 10 to 50 mol%, particularly 15 to 40 mol%, and more preferably 15 to 30 mol%. The weight average molecular weight of the cationic polymer flocculant is preferably about 12 million to 25 million, particularly about 15 million to 22 million. The addition amount of the cationic polymer flocculant is preferably 0.1 to 3 mg / L, particularly 0.5 to 2 mg / L.

  As such a cationic polymer, for example, a copolymer of a cationic monomer and acrylamide can be suitably used. Specific examples of the cationic monomer include dimethylaminoethyl acrylate and dimethylaminoethyl methacrylate (hereinafter, both compounds may be referred to as “dimethylaminoethyl (meth) acrylate”) or a quaternary ammonium salt thereof. Dimethylaminopropylacrylamide, dimethylaminopropylmethacrylamide (hereinafter, both compounds may be referred to as “dimethylaminopropyl (meth) acrylamide”) or their quaternary ammonium salts are preferably used. Yes, but not limited to this.

  The product form of the cationic polymer is not particularly limited, such as a powder product, a W / O type emulsion, or a dispersion in which cationic polymer flocculant particles are dispersed in an aqueous medium having a high salt concentration. It is applicable to the general circulation for waste water agglomeration treatment.

  The anionic polymer (anionic polymer flocculant) is preferably an acrylamide type, and the anionic group ratio is preferably 5 to 30 mol%, particularly 5 to 20 mol%. The weight average molecular weight of the anionic polymer is preferably 9 million to 20 million, particularly about 10 million to 18 million. The addition amount of the anionic polymer flocculant is preferably 0.2 to 8 mg / L, particularly 0.5 to 6 mg / L.

  As such an anionic polymer, for example, a copolymer of an anionic monomer and acrylamide, or a hydrolyzate of polyacrylamide can be used. As a specific example of the anionic monomer, acrylic acid or a salt thereof can be suitably used. Polymers copolymerized with acrylamide using 2-acrylamido-2-methylpropanesulfonic acid or a salt thereof together with acrylic acid or a salt thereof as an anionic monomer are particularly useful in that they can be used stably over a wide pH range. It can be used suitably.

  Each of the above embodiments is an example of the present invention, and the present invention may be configured other than illustrated.

1, 1 'Coagulation precipitation apparatus 2 Tank body 3, 4 Partition plate 5 Overflow plate 10 Machine room 11 Coagulation reaction tank 12 Precipitation tank 13 Sludge receiving tank 15 Stirrer 17 Transfer tray 18 Center well 18A Expanding part 19 Distributor 23 Stirring Wings 25 trough

Claims (5)

The planar view shape is a rectangle , and a rectangular parallelepiped tank as a whole ,
An agglomeration reaction tank and a precipitation tank formed by partitioning the tank body with a partition plate;
A sludge receiving tank adjacent to the sedimentation tank via a sludge overflow plate,
Cistern body is less than or equal to the width 2.2 m, length 5.6m or less state, and are less height 2.6 m,
A coagulating sedimentation apparatus , wherein a sludge outlet for taking out sludge in the sludge receiving tank is provided on a wall surface of the tank body . In claim 1, a center well is provided in the precipitation tank,
A coagulating sedimentation apparatus comprising a transfer member for allowing the coagulation reaction liquid in the coagulation reaction tank to flow into the center well. In Claim 2, a distributor extends radially from the lower portion of the center well,
A coagulating sedimentation apparatus characterized in that a drive device is provided for rotationally driving the center well about an axis. In any one of Claims 1 thru | or 3 ,
Coagulating sedimentation apparatus characterized by rake plate to move towards the soil Drott outlet along the bottom surface of the sludge receiving tank is provided. In claim 4, the rake plate is attached to a chain that is driven endlessly,
The chain is bridged between the drive side sprocket wheel and the driven side sprocket wheel so as to have a forward side along the bottom surface of the sludge receiving tank and a backward side arranged above the forward side.
The coagulation sedimentation apparatus, wherein an upper end of the rake plate when the rake plate is moved back by the chain is positioned lower than an upper edge of the overflow plate.

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