JP2018161636A - Coagulation sedimentation processing equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coagulation sedimentation treatment apparatus capable of suppressing deterioration of treated water quality. SOLUTION: A coagulation sedimentation treatment apparatus 100 supplies raw water to a sludge blanket portion S having a sludge blanket in which raw water flows in and captures solid matter contained in the raw water to generate treated water, and a sludge blanket portion S. The dispersion pipe 44 includes an inflow water discharge port 44a for discharging raw water, and the inflow water discharge port 44a is provided at a position lower than the minimum interface position I between the sludge blanket and the treated water. ing. [Selection diagram] Fig. 1

Description

  The present invention relates to a coagulation sedimentation processing apparatus.

  For example, a sludge blanket type coagulating sedimentation tank as disclosed in Patent Document 1 is known as a coagulating sedimentation tank that coagulates and precipitates organic substances by adding a coagulant to wastewater. The sludge blanket type coagulation sedimentation tank has a sludge blanket section with a blanket-like flock growth zone (sludge blanket) where flocs grow as the influent water to which the flocculant is added rises, and flows from below the sludge blanket section. And a distributor for supplying water.

JP 2010-274199 A

  In the sludge blanket type coagulation sedimentation treatment apparatus, the upper interface of the sludge blanket is sufficiently higher than the distributor during normal operation. Thereby, the floc etc. in the raw water supplied from the distributor are captured by the sludge blanket. However, if the supply amount of raw water decreases for some reason, the sludge blanket contracts and the interface of the sludge blanket decreases. Thereby, since the capacity | capacitance of sludge blanket becomes small, reaction in sludge blanket may become inadequate and we are anxious about the deterioration of treated water quality.

  This invention is made | formed in order to solve said subject, and it aims at providing the coagulation sedimentation processing apparatus which can suppress the fall of treated water quality.

  A coagulation sedimentation processing apparatus according to an embodiment of the present invention supplies raw water to a sludge blanket section having a sludge blanket section in which raw water flows in, captures solids contained in the raw water and generates treated water, and the sludge blanket section. And the distributor has a discharge hole for discharging the raw water, and the discharge hole is provided at a position lower than the lowest interface position between the sludge blanket and the treated water.

  In this coagulation sedimentation treatment apparatus, the discharge hole for discharging the raw water is provided at a position lower than the lowest interface position between the sludge blanket and the treated water. Here, the “minimum interface position” indicates the position of the interface between the sludge blanket and the treated water in a state where the sludge blanket is most contracted after a lapse of a predetermined time after the supply of raw water is stopped. By providing the discharge hole at such a low position, the raw water can be passed through the sludge blanket even when the sludge blanket contracts. Therefore, it becomes possible to suppress the reaction in the sludge blanket from becoming insufficient, and it is possible to suppress the deterioration of the treated water quality.

  In one form, a distributor may have the extension part extended to the bottom part side of a sludge blanket part, and the discharge hole may be provided in the extension part. According to this configuration, even when it is difficult to provide the entire distributor at a position lower than the lowest interface position, the discharge hole can be provided at a position lower than the lowest interface position by the extension. Therefore, it is possible to suppress degradation of the treated water quality while maintaining the degree of design freedom of the coagulation sedimentation treatment apparatus.

  In one form, the extension may be cylindrical. According to this configuration, raw water can be efficiently supplied into the sludge blanket. Therefore, it is possible to suppress the deterioration of treated water quality more efficiently.

  In one form, the extension part may have a collision plate that disperses the flow of raw water discharged from the discharge holes. According to this configuration, a turbulent flow is easily generated by the collision plate. Therefore, it is possible to improve the efficiency of the reaction in the sludge blanket.

  In one form, the distributor rotates and the discharge hole may be provided on the opposite side of the direction in which the distributor proceeds. According to this configuration, it is possible to reduce pressure loss when raw water is discharged from the discharge hole. Further, it is possible to prevent sludge from entering the discharge hole and blocking the discharge hole.

A coagulation sedimentation processing apparatus according to an aspect of the present invention includes a sludge blanket part having a sludge blanket that flows in raw water and captures solids contained in the raw water, and a concentration part that concentrates excess sludge generated in the sludge blanket part. A distributor for supplying raw water to the sludge blanket part, and the distributor has an extension extending to the bottom side of the sludge blanket and a discharge hole for discharging the raw water, and the discharge hole is provided in the extension part. Yes.
The distributor of this coagulation sedimentation processing apparatus has an extension part extending toward the bottom side of the sludge blanket part, and a discharge hole for discharging raw water is provided in the extension part. By providing the extension part and the discharge hole in this way, even when the sludge blanket contracts, the raw water can be passed through the sludge blanket. Therefore, it becomes possible to suppress the reaction in the sludge blanket from becoming insufficient, and it is possible to suppress the deterioration of the treated water quality.

  ADVANTAGE OF THE INVENTION According to this invention, the coagulation sedimentation processing apparatus which can suppress the fall of treated water quality is provided.

It is sectional drawing which shows schematically the coagulation sedimentation processing apparatus which concerns on one form of this invention. It is a figure which shows the structure of an extension part roughly. (A) And (b) is a figure which shows roughly the modification of the extension part shown by FIG. (A) And (b) is a figure which shows roughly the modification of the extension part shown by Fig.3 (a). It is a figure which shows schematically the modification of the extension part shown by FIG.

  Hereinafter, various embodiments will be described in detail with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a cross-sectional view schematically showing a coagulation sedimentation processing apparatus according to an embodiment of the present invention. The coagulation sedimentation processing apparatus according to the present embodiment has a coagulation sedimentation tank called a “sludge blanket type”. The sludge blanket type coagulation sedimentation tank forms a fluidized bed of coagulated flocs by the rising water flow in the tank, and allows newly generated flocs to pass through the fluidized bed. At this time, the small flocs are captured by the large flocs in the fluidized bed and become large, and the sedimentation speed increases. Thereby, the inflow water to the sludge blanket type coagulation sedimentation tank is separated into treated water and sludge, and each is discharged out of the tank. Hereinafter, flocs may be referred to as agglomerated flocs, sludge, or solids.

  The coagulation sedimentation processing apparatus 100 shown in FIG. 1 introduces inflow water containing coagulation flocs, grows the coagulation flocs in the sludge blanket formed in the sludge blanket part S, and then treats the coagulation flocs and processes as solids. Has the function of separating water. The inflow water introduced into the coagulation sedimentation treatment apparatus 100 includes, for example, an inorganic coagulant such as PAC (polyaluminum chloride) and a polymer coagulant such as an anionic polymer with respect to the raw water containing fine particles. Can be supplied. By mixing the flocculant with the raw water, flocculent flocs are generated.

  As shown in FIG. 1, the coagulation sedimentation treatment apparatus 100 of the present embodiment includes a bottomed cylindrical lower cylindrical water tank 1 and a bottomed cylindrical upper cylindrical water tank 2 provided above the lower cylindrical water tank 1. And comprising. In this coagulation sedimentation processing apparatus 100, the bottom part of the upper cylinder water tank 2 is spaced apart from the bottom part of the lower cylinder water tank 1 for a predetermined length, and has a double water tank structure. In addition, in this embodiment, although the lower cylinder water tank 1 and the upper cylinder water tank 2 are made into the cylindrical shape, a rectangular tube shape may be sufficient.

  The lower cylinder water tank 1 and the upper cylinder water tank 2 are arranged coaxially along the axis L. And the lower cylinder water tank 1 and the upper cylinder water tank 2 are provided in a part of outer periphery of the lower cylinder water tank 1 and the upper cylinder water tank 2, and are connected by the flow path 3 extended along the axis L in the up-down direction. . The flow path 3 surrounds the opening 12 formed in the side wall 11 of the lower cylinder water tank 1 and the opening 22 provided in the side wall 21 of the upper cylinder water tank 2 outside the side wall 21 of the upper cylinder water tank 2. The channel wall 31 extends in the vertical direction. In addition, in the area | region where the flow path 3 is not formed among the outer periphery of the lower cylinder water tank 1 and the upper cylinder water tank 2, the side wall 11 of the lower cylinder water tank 1 and the side wall 21 of the upper cylinder water tank 2 serve as the outer wall of the coagulation sedimentation processing apparatus 100. Form.

  In addition, in the coagulation sedimentation processing apparatus 100 shown in FIG. 1, although it has shown about the structure by which the upper direction of the flow path 3 was open | released, the closed structure may be sufficient. Moreover, although the flow path 3 has shown the example which has connected the opening 22 provided in the side wall 21 of the upper cylinder water tank 2, and the opening 12 of the lower cylinder water tank 1, the diameter of the upper cylinder water tank 2 is a lower cylinder. In the case of being smaller than the water tank 1, the shape of the flow path 3 can be changed as appropriate.

  An intermediate bottom plate 23 that forms the bottom of the upper cylinder water tank 2 is provided between the lower cylinder water tank 1 and the upper cylinder water tank 2. The intermediate bottom plate 23 becomes the top surface of the lower tubular water tank 1.

  A center shaft 40 is disposed on the axis L of the coagulation sedimentation processing apparatus 100. A feed pipe 41 is provided outside the center shaft 40 so as to surround the center shaft 40. The feed pipe 41 is connected to the inflow water distribution pipe 42. The inflow water distribution pipe 42 penetrates the side wall 21 of the upper tubular water tank 2 that forms the outer wall of the coagulation sedimentation treatment apparatus 100 and protrudes to the outside, and is connected to the upstream side. The inside of the inflow water distribution pipe 42 communicates with the inside of the feed pipe 41. The center shaft 40 is configured to be rotatable about an axis L by a drive source M.

  The feed pipe 41 is divided into an upper part 41a and a lower part 41b in the vertical direction, and the upper part 41a and the lower part 41b are connected by a rotary joint 43 such as a labyrinth structure. The feed pipe 41 is connected to the inflow water distribution pipe 42 at the side surface of the upper part 41a, and a dispersion pipe (distributor) 44 is provided at the lower part 41b of the feed pipe 41. The dispersion pipe 44 includes a pipe part T extending in a direction along the intermediate bottom plate 23 from the lower part 41b of the feed pipe 41, an extension part E extending from the pipe part T to the bottom side of the sludge blanket part S (the intermediate bottom plate 23 side), A plurality of inflow water discharge ports (discharge holes) 44a are provided. An inflow water discharge port (discharge hole) 44 a is provided in the extension E. The tube portion T is provided with a communication hole (not shown) for communicating the tube portion T and the extension portion E, and the extension portion E is formed so as to surround the communication hole. With such a structure, the inflow water flows from the pipe portion T to the extension portion E through the communication hole, and is discharged into the sludge blanket portion S from the inflow water discharge port (discharge hole) 44a provided in the extension portion E. The In the present embodiment, a plurality of communication holes are provided along the direction in which the tube portion T extends, and an extension E is provided for each communication hole. The dispersion pipe 44 rotates together with the center shaft 40 in a state in which the inflow water discharge port 44 a faces the intermediate bottom plate 23 side that forms the bottom of the upper tubular water tank 2. At this time, the lower part 41 b of the feed pipe 41 rotates together with the dispersion pipe 44.

  The center shaft 40 is connected to the intermediate bottom plate 23 by a rotary joint, a mechanical seal, an oil seal, a gland packing, and the like, and further extends downward. A concentrated sludge scraper 45 is provided at the lower end of the center shaft 40. As the center shaft 40 rotates, the concentrated sludge scraper 45 also rotates. The concentrated sludge scraping machine 45 is provided on the bottom surface 13 of the lower tubular water tank 1 that forms the outer wall of the coagulation sedimentation treatment apparatus 100 and scrapes the concentrated sludge accumulated on the bottom surface 13 to the center. The concentrated sludge raked out is discharged outward from the discharge port 14.

  In the coagulation sedimentation treatment apparatus 100, a region below the opening 22 in the upper tubular water tank 2 functions as the sludge blanket portion S. Moreover, the inside of the flow path 3 which connects the opening 22 of the upper cylinder water tank 2 and the opening 12 of the lower cylinder water tank 1 functions as a sedimentation zone Z1 in which sludge (excess sludge generated by the sludge blanket) is settled. Moreover, the area | region where the concentrated sludge scraper 45 in the lower cylinder water tank 1 is provided functions as the concentration zone (concentration part) Z2 which concentrates excess sludge. Said sedimentation zone Z1 and concentration zone Z2 function as a discharge part for discharging excess sludge to the outside. The sludge blanket part S and the discharge part (sedimentation zone Z1 and concentration zone Z2) are adjacent to each other through the side wall 21 (of which the flow path 3 is formed) and the intermediate bottom plate 23.

  Next, the dispersion tube 44 of the coagulation sedimentation processing apparatus 100 according to the present embodiment will be described in detail with reference to FIG. FIG. 2 is a diagram schematically showing the structure of the extension. FIG. 2 is a view when the dispersion tube 44 is viewed from the direction in which the tube portion T extends. As shown in FIG. 2, the dispersion pipe 44 has an extension E, and the inflow water discharge port 44 a is provided in the extension E. The extension portion E is provided so as to extend from the dispersion pipe 44 to the intermediate bottom plate 23 side (the bottom portion side of the sludge blanket portion S). The extension E extends, for example, at a right angle to the dispersion tube 44. In addition, the extension part E should just extend to the intermediate | middle bottom plate 23 side, and the angle which the extension part E and the dispersion pipe 44 make is not specifically limited. The extension portion E has a cylindrical shape, and is provided, for example, in a cylindrical shape in the present embodiment. That is, the cross section of the extension part E from the dispersion pipe 44 to the inflow water discharge port 44a is closed on a plane that intersects the direction in which the extension part E extends (a plane along the intermediate bottom plate 23). In addition, the extension part E is not limited to a cylindrical shape, For example, it can be set as arbitrary shapes, such as a rectangular tube shape.

  The inflow water discharge port 44a is provided at the end of the extension E on the intermediate bottom plate 23 side. In the present embodiment, the extension E extends to a position (intermediate bottom plate 23 side) lower than the lowest interface position I between the sludge blanket part S and the treated water. Therefore, the inflow water discharge port 44a is provided at a position lower than the lowest interface position I (on the intermediate bottom plate 23 side). The inflow water discharged from the inflow water discharge port 44a collides with the intermediate bottom plate 23 and disperses, and passes through the sludge blanket portion S. Here, the “minimum interface position” indicates the position of the interface between the sludge blanket part S and the treated water in a state where the sludge blanket part S contracts most after a lapse of a predetermined time after the supply of raw water is stopped. . As an example, the lowest interface position I can be a position of 100 mm or more from the intermediate bottom plate 23. In this case, the distance between the inflow water discharge port 44a and the intermediate bottom plate 23 can be 50 mm or more and 200 mm or less. it can. Moreover, it is preferable that the inflow water discharge port 44a is 50 mm or more with respect to the lowest interface position I, and is located in the intermediate | middle bottom plate 23 side.

  As described above, in the coagulation sedimentation processing apparatus 100, the inflow water discharge port 44a for discharging raw water is provided at a position lower than the lowest interface position I between the sludge blanket portion S and the treated water. The sludge blanket part S contracts due to, for example, a decrease in the amount of inflow water supplied, and the interface between the sludge blanket part S and the treated water decreases. In such a case, the reaction in the sludge blanket part S becomes insufficient, and there is a possibility that the quality of the treated water is lowered. In particular, when the interface between the sludge blanket portion S and the treated water is lowered to a position lower than the influent water discharge port 44a (on the side of the intermediate bottom plate 23), the influent water does not pass through the sludge blanket portion S. Is prone to decline. On the other hand, by providing the inflow water discharge port 44a at a low position as in the present embodiment, the incoming water can be passed through the sludge blanket portion S even when the sludge blanket portion S contracts. Therefore, it becomes possible to suppress the reaction in the sludge blanket part S from becoming insufficient, and it is possible to suppress the deterioration of the treated water quality.

  Further, even when the interface between the sludge blanket part S and the treated water is at the lowest interface position I, the incoming water can be passed through the sludge blanket part S. For example, when the coagulation sedimentation treatment apparatus 100 is started up, It is possible to shorten the raising time (time until the treated water quality is stabilized).

  Further, the dispersion pipe 44 has an extension E extending to the bottom side of the sludge blanket part S, and the inflow water discharge port 44 a is provided in the extension E. Accordingly, even when it is difficult to provide the entire dispersion pipe 44 at a position lower than the lowest interface position I, the inflow water discharge port 44a can be provided at a position lower than the lowest interface position I by the extension E. Therefore, it is possible to suppress deterioration in the quality of the treated water while maintaining the design freedom of the coagulation sedimentation treatment apparatus 100.

  Moreover, the extension part E is cylindrical. Thereby, inflow water can be efficiently supplied in the sludge blanket part S. Therefore, it is possible to suppress the deterioration of treated water quality more efficiently.

(Modification)
Next, a modified example of the extension E shown in the above embodiment will be described.

  FIG. 3 schematically shows a modification of the extension shown in FIG. FIG. 3A shows an extension E1 according to the first modification, and FIG. 3B shows an extension E2 according to the second modification. The extension parts E1 and E2 according to the modification are different from the extension part E in that the inflow water discharge port 44a is provided on the opposite side of the traveling direction D of the dispersion pipe 44.

  As shown in FIG. 3A, the extension E1 according to the first modified example intersects the first portion E11 extending from the dispersion pipe 44 toward the intermediate bottom plate 23, the first portion E11, and the traveling direction D. And a second portion E12 extending in the opposite direction. The second portion E12 is provided at the end of the first portion E11 on the intermediate bottom plate 23 side. The inflow water discharge port 44a is provided at the end of the second portion E12 at a position lower than the lowest interface position I. The angle θ formed by the first portion E11 and the second portion E12 can be, for example, about 90 °. The angle θ is not particularly limited and can be arbitrarily set, but is preferably 90 ° or more in order to supply the inflowing water to the bottom side (intermediate bottom plate 23 side) of the sludge blanket portion S.

  Thus, since the inflow water discharge port 44a is also provided at a position lower than the lowest interface position I in the extension portion E1, it is possible to suppress degradation of the treated water quality as in the above embodiment. Moreover, it is possible to reduce pressure loss when inflowing water is discharged from the inflowing water discharge port 44a. Furthermore, it is possible to prevent sludge from entering the inflow water discharge port 44a and blocking the inflow water discharge port 44a.

  Moreover, as shown in FIG. 3B, in the extension E2 according to the second modification, an inflow water discharge port 44a is provided on the side surface of the extension E2. More specifically, the inlet water discharge port 44a is provided on the opposite side of the traveling direction D at a position lower than the lowest interface position I. Also in this case, the same effect as the extension part E1 which concerns on a 1st modification can be obtained.

  FIG. 4 is a diagram schematically showing a modification of the extension shown in FIG. FIG. 4A shows an extension E3 according to the third modification, and FIG. 4B shows an extension E4 according to the fourth modification. The extension part E3 according to the third modification example and the extension part E4 according to the fourth modification example are different from the extension part E1 according to the first modification example in that the flow of the inflow water discharged from the inflow water discharge port 44a is dispersed. It is the point which further has the collision board P to be made.

  As shown in FIG. 4 (a), the extension E3 according to the third modification is similar to the extension E1 according to the first modification, and a first portion E31 extending from the dispersion tube 44 toward the intermediate bottom plate 23 side. The second portion E32 intersects with the first portion E31 and extends in the direction opposite to the traveling direction D. The inflow water discharge port 44a is provided at the end of the second portion E32 at a position lower than the lowest interface position I. The collision plate P is provided on the downstream side of the inflow water discharge port 44a in the traveling direction D. In the example shown in FIG. 4A, the collision plate P is provided substantially perpendicular to the intermediate bottom plate 23. Even in the case where the extension portion E3 is provided in this way, the same operational effects as those of the extension portion E1 according to the first modification can be obtained. Moreover, since the turbulent flow is easily generated by the collision plate P, the efficiency of the reaction in the sludge blanket portion S can be improved.

  4B, in the extension E4 according to the fourth modification, the collision plate P has a collision surface P1 of the collision plate P (one surface that collides with the inflowing water) P1 on the intermediate bottom plate 23 side. Fixed in an inclined state. Thereby, inflow water can be supplied to the bottom part side (intermediate bottom plate 23 side) of the sludge blanket part S more efficiently.

  FIG. 5 schematically shows a modification of the extension shown in FIG. As shown in FIG. 5, the extension portion E5 according to the fifth modification differs from the extension portion E in that the extension portion is in a plane (plane along the intermediate bottom plate 23) intersecting with the direction in which the extension portion E5 extends. The section E5 is not closed. For example, the extension part E5 may be a plate-like member that extends to the bottom side of the sludge blanket part S. In this case, an opening O is provided in the dispersion pipe 44 itself, and the inflow water flowing out from the opening O is guided into the sludge blanket part S by the extension part E5. That is, the opening formed between the two extension portions E5 provided on both sides of the opening O corresponds to the inflow water discharge port 44a. Even in such a case, since the inflow water discharge port 44a can be provided at a position lower than the lowest interface position I, it is possible to suppress deterioration in the quality of the treated water.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment, A various deformation | transformation aspect is employable. For example, in the above embodiment, one inflow water discharge port 44a is provided for each extension E, but a plurality of inflow water discharge ports 44a are provided for one extension E. Also good.

  Moreover, in the said embodiment, although the inorganic flocculant and the polymer flocculant were added with respect to raw | natural water, the operation | movement introduced into the flocculent precipitation processing apparatus 100 which coarsens a floc was demonstrated, The kind of flocculant to add, etc. Is not particularly limited. Moreover, it is good also as a structure introduce | transduced into the coagulation sedimentation processing apparatus 100 as inflow water, without adding a coagulant | flocculant depending on the kind of raw | natural water.

  DESCRIPTION OF SYMBOLS 1 ... Lower cylinder water tank, 2 ... Upper cylinder water tank, 3 ... Channel, 11 ... Side wall, 13 ... Bottom surface, 14 ... Discharge port, 21 ... Side wall, 23 ... Middle bottom plate, 31 ... Channel wall, 40 ... Center shaft, DESCRIPTION OF SYMBOLS 41 ... Feed pipe, 42 ... Inflow water distribution pipe, 43 ... Rotary joint, 44 ... Dispersion pipe (distributor), 44a ... Inflow water discharge port (discharge hole), 45 ... Concentrated sludge scraper, 100 ... Coagulation sedimentation processing apparatus , D ... traveling direction, E1, E2, E3, E4, E5 ... extension, I ... lowest interface position, L ... axis, M ... drive source, P ... collision plate, S ... sludge blanket part, T ... pipe part, Z1 ... sedimentation zone, Z2 ... concentration zone.

Claims (6)

A sludge blanket part having a sludge blanket into which raw water flows and captures solids contained in the raw water to generate treated water;
A distributor for supplying the raw water to the sludge blanket part,
The distributor has a discharge hole for discharging the raw water,
The said discharge hole is a coagulation sedimentation processing apparatus provided in the position lower than the lowest interface position of the said sludge blanket and the said treated water. The distributor has an extension extending to the bottom side of the sludge blanket part,
The coagulation sedimentation processing apparatus according to claim 1, wherein the discharge hole is provided in the extension portion.   The coagulation sedimentation processing apparatus according to claim 2, wherein the extension portion is cylindrical.   The coagulation sedimentation processing apparatus according to claim 2 or 3, wherein the extension includes a collision plate that disperses the flow of the raw water discharged from the discharge hole. The distributor rotates,
The coagulation sedimentation processing apparatus according to any one of claims 1 to 4, wherein the discharge hole is provided on a side opposite to a direction in which the distributor travels. A sludge blanket part having a sludge blanket into which raw water flows and captures solids contained in the raw water;
A concentrating section for concentrating excess sludge generated in the sludge blanket section;
A distributor for supplying the raw water to the sludge blanket part,
The distributor has an extension extending to the bottom side of the sludge blanket part, and a discharge hole for discharging the raw water,
The coagulation sedimentation processing apparatus, wherein the discharge hole is provided in the extension.

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