JP4934925B2 - Coagulation sedimentation equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is composed of a plurality of hollow radiating tubes projecting radially from a central portion, and a distributor that swirls horizontally in one direction in a sludge blanket layer in a bottom of a settling tank (thickener), and inside the settling tank. A center well that enters the water from the liquid surface and receives raw water to be treated (mixed liquid of coagulant and sludge), and is supported vertically in the water of the settling tank, and the raw water received by the center well is received by the distributor. It consists of a center column that feeds the raw water into the sludge blanket layer from the outlet provided in each hollow radiant tube, and the SS in the raw water discharged from the distributor outlet into the sludge blanket layer. The sludge is newly separated in the sludge blanket layer. About sludge blanket type flocculator device for the waste sludge from the center of the bottom of the sedimentation tank while concentrated by Atsumaridoro member (rake) that pivots together under the distributor sludge layer containing.
[0002]
[Prior art]
The present applicant has proposed a sludge blanket type coagulating sedimentation apparatus having the same configuration in Japanese Patent Application No. 2000-325397. This leading device connects the center column and the distributor so as to rotate integrally, separates the lower end of the fixed center well and the upper end of the rotating center column, and detaches both parts in the water above the sludge blanket layer. Although it is slidably connected in a rotatable manner with a seal and functions as it is, the following problems arise.
[0003]
[Problems to be solved by the invention]
{Circle around (1)} Since the seal wears out during long-term use and eventually disappears, it needs to be repaired regularly, which is troublesome.
(2) Since the rotatable connecting part is located in the water above the sludge blanket layer, the raw water leaks into the sedimentation tank from between the sliding seals, and the SS in the raw raw water is leaked from the sludge blanket layer. It is mixed with treated water without being treated to deteriorate the quality of the treated water.
[0004]
[Means for Solving the Problems]
The present invention was developed in order to solve the above-mentioned problems, and comprises a central portion provided with a circular opening on the upper surface and a plurality of hollow radiation tubes projecting radially from the central portion. A distributor that swirls horizontally in the sludge blanket layer deposited at the bottom and the raw water to be treated that is supported in the vertical direction in the water of the settling tank and that is stirred and mixed with the flocculant and sludge is received, and this raw water is It consists of a cylindrical fixed center column that leads to the opening at the center of the distributor at the lower end, and the raw water introduced from the center column passes through the distributor to each hollow radiant tube and is opposite to the direction of swiveling of the distributor. In a sludge blanket type coagulating sedimentation device which discharges into a sludge blanket layer from a discharge port provided in a direction. , And the lower end of the center column to form a communicating portion in sliding contact by face close without providing a seal for sliding contact with an opening provided in the central upper surface of the distributor, and communicating portion sludge blanket The sludge blanket layer captures SS in the raw water leaking from the communicating portion . In this case, in order to allow the lower end of the center column to communicate with the inside of the central portion of the distributor in a rotatable manner, the lower end of the center column may be opposed to the outer periphery of the opening on the upper surface of the central portion of the distributor. An upward cylindrical portion may be provided on the outer periphery of the opening on the upper surface, and the lower end portion of the center column may be fitted outside the upward cylindrical portion, or the lower end of the center column facing the outer periphery of the opening on the upper center portion of the distributor. There may be a flange protruding outward, or an upward cylindrical part is provided on the outer periphery of the opening on the upper surface of the center part of the distributor so as to be fitted to the inner periphery of the lower end part of the center column and around the lower end part of the center column. In addition, an outwardly projecting ridge facing around the opening on the upper surface of the center of the distributor may be provided, or the center column The outer periphery of the end portion may be opposed to the inner periphery of the opening on the upper surface of the center portion of the distributor, the outer periphery of the lower end portion of the center column may be inserted into the opening of the upper surface of the center portion of the distributor, In this case, an outwardly protruding ridge facing the outer periphery of the opening on the upper surface of the central portion of the distributor may be provided on the lower end portion that has entered the opening on the upper surface of the central portion of the distributor.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Reference numeral 10 denotes a cylindrical sedimentation tank having a mortar-like bottom, and a sludge blanket layer 11 is deposited on the bottom. The sedimentation tank has a pit 12 at the center of the bottom, and a sewage pipe 12 'is connected to the pit. Reference numeral 13 denotes a fixed center column (not shown) along the center of the sedimentation tank 10 but supported in the vertical direction, with the lower end reaching the inside of the sludge blanket layer 11, and the center well 14 is integrally attached to the upper end. . The center well enters the water from the liquid level inside the settling tank, receives raw water (mixed liquid of the flocculant and sludge) obtained by stirring and mixing the flocculant in the coagulation tank 1 and the like through the trough 2, and supplies it to the center column. .
[0006]
15 is composed of a plurality of hollow radiating tubes 16 projecting radially from the central portion, and the inside of the central portion is rotatably communicated with the lower end of the center column 14 in the sludge blanket layer 11 at the bottom of the settling tank. Shows a distributor that turns horizontally in one direction.
[0007]
In the illustrated embodiment, the distributor 15 includes four hollow radiating tubes 16 arranged at a phase of 90 °. The motor, the speed reducer M, the center well, the center column, and the distributor are supported above the center well 14. It is fixed to a rotating shaft 18 that hangs down through the center, and rotates horizontally in one direction. The rotating shaft 18 passes through the center of the distributor, and the lower end is supported at the center of the bottom of the pit 12.
[0008]
Each hollow radiant tube of the distributor is provided with a discharge port 17 for discharging the raw water supplied to the center of the distributor into the sludge blanket layer 11 in a direction opposite to the turning direction of the distributor (arrow a). is there. In FIG. 1 (A), the discharge port 17 is shown as a plurality of round openings provided at intervals in the longitudinal direction of the hollow radiation tube, but the shape is not limited to a round shape and is continuous in the longitudinal direction. A series of slits may be used. A radial rake 19 that rotates in contact with the bottom surface of the sedimentation tank and collects the sludge concentrated on the bottom surface in the pits 12 is fixed under each hollow radiation tube of the distributor 15.
[0009]
1 to 7, a circular opening 20 is provided on the upper surface of the central portion of the distributor where the four hollow radiation tubes 16 are gathered.
[0010]
In the embodiment of FIG. 1, the lower end of the center column 13 is opposed to the outer periphery of the opening 20 from above as shown in FIG. By making them face each other close to each other, the fixed center column and the rotating distributor are brought into sliding contact with each other, and a communication portion A is formed in which raw water flows from the center column into the distributor. The flow of raw water descending in the center column is supplied into the distributor 15 through the communication part A. Since the opposed portion of the lower end of the center column 13 and the outer periphery of the opening 20 of the distributor is provided close to each other, resistance is given to the water flow, and almost all of the raw water flow rate passes through the easy-to-flow opening 20. Enter the distributor. Even if a part of the raw water may leak into the sludge blanket layer 11 without entering the distributor from the gap 21 between the opposing parts as indicated by the arrows, the SS in the raw raw water leaks out of the sludge blanket layer 11. Therefore, the quality of the treated water flowing upward in the sedimentation tank and overflowing to the overflow trough 10 'on the outer periphery is not deteriorated.
[0011]
In the embodiment of FIG. 2, an upward cylindrical portion 22 is provided around the opening 20 on the upper surface of the central portion of the distributor, the lower end portion of the center column 13 is fitted to the inner periphery of the upward cylindrical portion 22, and the lower end of the center column is It faces the upper surface of the central portion of the distributor on the outer periphery of the upward cylindrical portion. In this case, the resistance of the water flow is increased by the amount that the upward cylindrical portion 22 is fitted to the inner periphery of the lower end portion of the center column 13 from below, and the raw water leaking into the sludge blanket layer 11 from the gap 21 having the L-shaped cross section. The amount is reduced. Further, since the distributor turns with the upward cylindrical portion 22 fitted to the inner periphery of the lower end portion of the fixed center column 13, the turning of the distributor is stabilized.
[0012]
In the embodiment of FIG. 3, a flange 23 projecting to the outer periphery is provided at the lower end of the center column, and this flange 23 is opposed to the outer periphery of the opening 20 on the upper surface of the central portion where the hollow radiation tubes are gathered. Accordingly, also in this case, the amount of raw water leaking from the gap 21 into the sludge blanket layer is reduced by the area of the ridge 23 facing the outer periphery of the opening 20 from above. Moreover, since the flow of raw water leaking from the gap 21 is initially regulated in the horizontal direction by the ridges 23, the sludge blanket layer 11 on the distributor is not disturbed upward. Therefore, the sludge blanket layer can easily capture the SS in the leaked raw water and reliably prevent the SS from being mixed into the treated water.
[0013]
FIG. 4 shows an embodiment in which the embodiment of FIG. 2 and the embodiment of FIG. 3 are used in combination. In the case of this embodiment, part of the raw water flowing down in the center column and leaking into the sludge blanket layer 11 is a gap 21a between the inner periphery of the lower end portion of the center column 13 and the upward cylindrical portion 22, and the lower end of the center column. Since it must pass through both the gap 21b between the outer peripheral flange 23 and the upper surface of the central portion of the distributor, the resistance of the leaking flow is increased, and the amount of leakage is suppressed. Of course, as in the embodiment of FIG. 2, both the rotation of the distributor is stable, and the SS of the embodiment of FIG. 3 is easily captured.
[0014]
In the embodiment of FIG. 5, the inner periphery of the opening 20 provided on the upper surface of the central portion of the distributor and the outer periphery of the lower end of the center column 13 are opposed to form a gap 21. Since the raw water flows down inside the center column, the amount of raw water leaking back through the gap 21 and leaking into the sludge blanket layer decreases.
[0015]
In the embodiment of FIG. 6, the lower end portion of the center column penetrates deeper than the embodiment of FIG. In this case, the downward flow of the raw water entering the distributor from the inside of the center column has a smaller resistance than the flow of the raw water leaking from the gap 21 to the sludge blanket layer. Less than the example.
[0016]
In the embodiment of FIG. 7, the center column of the embodiment of FIG. 6 is provided with a flange 23 facing the upper surface of the central portion of the distributor with a narrow gap 21c. In the case of this embodiment, the amount of raw water leaking into the sludge blanket layer is small as in the embodiment of FIG. 5, but the flow of the leaked raw water is leveled by the ridge 23, so that the embodiment of FIGS. Similarly, the SS is easily captured without disturbing the sludge blanket layer 11.
[0017]
Each of the embodiments shown in FIGS. 1 to 7 has a circular opening 20 with a plurality of hollow radiating tubes 16 having a square cross section or a D-shaped cross section with a flat surface 16 'facing upward as shown in FIG. The upper surface of the central portion where the hollow radiation tubes to be opened are horizontal, and the center column lower end surface or the flange 23 is disposed close to the above-described horizontal upper surface, whereby the gap 21 can be reduced.
[0018]
In addition, when the circular opening 20 is opened on the horizontal upper surface of the central portion where the hollow radiating tubes are gathered as shown in FIG. 8, the center column 13 has a diameter approximately equal to the diameter of the opening 20. The communication portion formed by the lower end of the nozzle and the distributor is watertight except for the gap 21. The diameter D of the opening 20 is not limited to the diameter of a circle inscribed in the central portion where a plurality of hollow radiating tubes are gathered, and is acceptable if it is slightly larger than that. In this case, when the communication portion is formed, a slight gap is formed in the branch portion near the root of the radiation tubes 16 and 16 ', and a small amount of raw water leaks into the sedimentation tank, but even if it leaks, it enters the sludge blanket layer. It becomes a downward flow, and the SS component in the leaked raw water is captured by the layer without disturbing the sludge blanket layer.
[0019]
In order to prevent leakage of raw water from other than the gap 21, as shown in FIG. 9, a hollow raw water receiving chamber 30 having a diameter larger than that of the center column 13 and having a flat upper surface is provided at the center of the distributor 15. A plurality of hollow radiation tubes 16 are projected radially from the side surfaces, and a circular opening 31 corresponding to the lower end of the center column is opened at the center of the flat upper surface of the receiving chamber. What is necessary is just to implement between the lower end of a center column, and the said opening 31. FIG.
[0020]
In the embodiment of FIG. 9, the raw water receiving / distributing chamber 30 is a cylindrical shape having a low height, but may be a polygonal shape.
[0021]
【Effect of the invention】
According to the present invention, the lower end of the fixed center column and the opening at the upper surface of the central portion of the rotating distributor concentrically disposed thereunder communicate with each other without providing a seal in sliding contact with the raw water from the center column to the distributor. Since it is supplied, it is not necessary to interrupt the operation due to the wear of the seal and to replace the seal, thereby improving the processing efficiency. Furthermore, since the communication part between the lower end of the center column and the opening on the upper surface of the distributor is located in the sludge blanket layer, even if a part of the raw water supplied downward to the center column and supplied to the distributor leaks from the communication part, Since the SS in the raw raw water leaked is captured and filtered by the sludge blanket layer, the quality of the treated water is not deteriorated.
[Brief description of the drawings]
FIG. 1A is a schematic view of an embodiment of the present invention, and FIG. 1B is an enlarged view of a main part of the same.
FIG. 2 is an enlarged view of a main part of a second embodiment of the present invention.
FIG. 3 is an enlarged view of a main part of a third embodiment of the present invention.
FIG. 4 is an enlarged view of a main part of a fourth embodiment of the present invention.
FIG. 5 is an enlarged view of a main part of a fifth embodiment of the present invention.
FIG. 6 is an enlarged view of a main part of a sixth embodiment of the present invention.
FIG. 7 is an enlarged view of a main part of still another embodiment of the present invention.
FIG. 8 is a perspective view of an example of a distributor according to the present invention.
FIG. 9 is a perspective view of another example of the distributor of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Coagulation tank 2 Trough 10 Sedimentation tank 11 Sludge blanket layer 12 Pit 12 'Mud pipe 13 Center column 14 Center well 15 Distributor 16 Distributor hollow radiation pipe 17 Hollow radiation pipe raw water outlet 18 Rotating shaft 19 Lake 20 Distributor Opening 21, 21 a, 21 b, 21 c on the upper surface of the central portion Clearance A Communication portion 22 Upward cylindrical portion 23 鍔 30 Raw water receiving chamber 31 Opening on the upper surface of the central portion of the raw water receiving chamber

Claims (8)

Distributor which horizontally rotates in a sludge blanket layer deposited on the bottom of a sedimentation tank, comprising a central portion having a circular opening on the upper surface and a plurality of hollow radiation tubes projecting radially from the central portion. And a cylindrical fixing that is supported in the vertical direction in the water of the settling tank, receives the raw water to be treated by stirring and mixing the flocculant and sludge, and guides this raw water to the opening at the center of the distributor at the lower end. The raw water introduced from the center column is discharged into the sludge blanket layer from the outlet provided in each hollow radiant tube through the distributor and in the direction opposite to the swirling direction of the distributor. In the sludge blanket type coagulating sedimentation apparatus, the lower end of the center column and the distributor Center communication portion formed in sliding contact by face close without providing a seal for sliding contact with an opening provided on the upper surface, and communicating portion is to be positioned in the sludge blanket layer, communicating portion A coagulation sedimentation apparatus characterized in that SS in raw water leaking from the water is trapped in a sludge blanket layer . 2. The coagulation sedimentation apparatus according to claim 1, wherein the lower end of the center column is opposed to the outer periphery of the opening in the upper surface of the central portion of the distributor. 3. The coagulation sedimentation apparatus according to claim 2, wherein an upward cylindrical portion is provided on an outer periphery of an opening in an upper surface of a central portion of the distributor, and a lower end portion of a center column is fitted outside the upward cylindrical portion. apparatus. 2. The coagulation sedimentation apparatus according to claim 1, wherein a ridge projecting outward is provided at the lower end of the center column facing the outer periphery of the opening in the upper surface of the central portion of the distributor. In the coagulation sedimentation apparatus according to claim 3, an upward cylindrical portion is provided on the outer periphery of the opening of the upper surface of the central portion of the distributor so as to be fitted to the inner periphery of the lower end portion of the center column and around the lower end portion of the center column, An agglomeration sedimentation apparatus, characterized in that an outwardly projecting ridge is provided around the opening on the upper surface of the center of the distributor. The coagulation precipitation apparatus according to claim 1, wherein the outer periphery of the lower end portion of the center column is opposed to the inner periphery of the opening at the upper surface of the center portion of the distributor. The coagulation sedimentation apparatus according to claim 1, wherein the outer periphery of the lower end portion of the center column is plunged into the opening of the upper surface of the center portion of the distributor. 2. The coagulation sedimentation apparatus according to claim 1, wherein the center column projects outwardly opposite to the outer periphery of the central upper surface opening of the distributor on the lower end portion projecting into the central upper surface opening of the distributor. An agglomeration sedimentation apparatus characterized by providing a bowl.

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