JP2005046786A - Flocculation and sedimentation apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flocculation and sedimentation apparatus capable of rectifying water to be treated flowing in a solid-liquid separation tank so as to extend the same over the entire surface of the water area of the solid-liquid separation tank, capable of enhancing solid-liquid separation efficiency in the solid-liquid separation tank and dispensing with a large-scaled means like a conventional inclined plate. <P>SOLUTION: This flocculation and sedimentation apparatus is equipped with a flocculation reaction tank 3 for flocculating a suspended substance or the like in water to be treated, an additive supply means 12 for supplying an insoluble granular additive to the water to be treated and the solid-liquid separation tank 4 for subjecting the outflow water from the flocculation reaction tank 3 to solid-liquid separation. A flow rectifying plate unit 20 comprising a plurality of vertical flow rectifying plates are installed in the solid-liquid separation tank 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a coagulation sedimentation apparatus which has improved solid-liquid separation performance in the field of water treatment.

  As a conventional coagulation sedimentation apparatus, a coagulation reaction tank that coagulates suspended substances in the water to be treated, an additive supply means that supplies insoluble particulate additives to the water to be treated, and effluent water from the coagulation reaction tank The thing of the structure provided with the solid-liquid separation tank which introduce | transduces and solid-liquid-separates is already known. In such a coagulation sedimentation apparatus, there is a short-circuit flow due to the flow rate of the water to be treated flowing into the solid-liquid separation tank and the non-uniformity of the water temperature in the solid-liquid separation tank. The actual precipitation time is shorter than the hydraulic precipitation time, and the solid-liquid separation effect is reduced. For this reason, the solid-liquid separation tank is designed to take a long precipitation time. In addition, it is also known that a plurality of inclined plates are installed in the solid-liquid separation tank in order to promote sedimentation of suspended substances and the like.

  The above prior art is a technique generally known to those skilled in the art, and does not relate to a known literature invention.

  Although the conventional coagulation sedimentation apparatus is configured as described above, and the inclined plate is installed in the solid-liquid separation tank, it is possible to improve the sedimentation efficiency by promoting sedimentation and rectification in the solid-liquid separation tank. Since solid matter such as suspended solids in the water to be treated flowing into the solid-liquid separation tank adheres to the inclined plates, the gap between the inclined plates becomes narrower or non-uniform. The precipitation efficiency is reduced. Therefore, it is necessary to periodically wash the inclined plate, but there is a problem that the washing work requires a lot of labor and time and is extremely difficult. In addition, since the inclined plate is installed in the tank for a solid-liquid separation tank designed to have a longer sedimentation time, if the flow rate of the inflow water of the solid-liquid separation tank is increased, the inclined plate As a result, there is a problem that a drift of separated water occurs in the solid-liquid separation tank.

  The present invention has been made to solve the above-described problems, and the water to be treated flowing into the solid-liquid separation tank can be rectified so as to spread over the entire water area of the solid-liquid separation tank. An object of the present invention is to provide a coagulation sedimentation apparatus that can increase the solid-liquid separation efficiency in the separation tank and does not require a large-scale washing like a conventional inclined plate.

  The coagulation sedimentation apparatus according to the present invention comprises a coagulation reaction tank for coagulating suspended substances in the water to be treated, additive supply means for supplying insoluble particulate additives to the water to be treated, In a coagulation sedimentation apparatus provided with a solid-liquid separation tank for solid-liquid separation of effluent water, a rectifying plate unit composed of a plurality of vertical rectifying plates is installed in the solid-liquid separation tank.

  According to the present invention, the agglomeration reaction tank for aggregating suspended substances in the water to be treated, the additive supply means for supplying insoluble particulate additives to the water to be treated, and the effluent water from the agglomeration reaction tank. In a coagulation sedimentation apparatus equipped with a solid-liquid separation tank that is introduced and separated into a solid and a liquid, rectification is made up of a plurality of vertical current plates arranged in the crossing or longitudinal direction of the solid-liquid separation tank and in the combination direction thereof. Since it has a plate unit and the separated water is circulated between the flow straightening plates, the water to be treated flowing into the solid-liquid separation tank can be raised vertically by the flow straightening plate, By the vertical rectifying action, there is an effect that the separated water can be evenly distributed without uneven flow over the entire water area of the solid-liquid separation tank.

  In addition, according to the present invention, as described above, the water to be treated that has flowed into the solid-liquid separation tank can be raised in the vertical direction by the rectifying plate, so that the separated water can be prevented from drifting and the additive It is possible to promote the sedimentation of the solid matter containing slag in the vertical direction, and therefore, the frequency that the solid matter adheres to the current plate is extremely reduced, and the frequency of cleaning the current plate can be reduced. Furthermore, even if the flow rate of the water to be treated in the solid-liquid separation tank is increased, the separated water does not drift and there is an effect that the solid-liquid separation efficiency is greatly improved. Furthermore, there is an effect that the current plate can be prevented from being corroded by antibacterial treatment.

Embodiment 1 FIG.
FIG. 1 is a sectional view showing a coagulation sedimentation apparatus according to Embodiment 1 of the present invention.
In FIG. 1, 1 is a rapid agitation tank into which water to be treated is introduced, 2 is an agitation agitation tank, 3 is an agglomeration reaction tank (floc formation tank) that agglomerates suspended substances in the water to be treated that have flowed from the injection agitation tank 2. 4) is a solid-liquid separation tank for solid-liquid separation of the inflow water from the aggregation reaction tank 3. In each of the rapid stirring tank 1, the injection stirring tank 2 and the agglomeration reaction tank 3, stirrers 5 to 7 are installed. Reference numeral 8 denotes a centrally driven sludge scraper installed in the solid-liquid separation tank 4, and the sludge scraper 8 is driven to rotate by a motor 9. Reference numeral 10 denotes a drawing pipe for drawing separated sludge and the like from the bottom of the solid-liquid separation tank 4, and a drawing pump 11 is provided in the drawing pipe 10.

  Reference numeral 12 denotes a liquid cyclone serving as an additive supply means for supplying a granular additive (sand or the like) that is insoluble in the water to be treated in the pouring / stirring tank 2, and the liquid cyclone 12 includes a transfer terminal portion of the drawing pipe 10. Is connected. The liquid cyclone 12 separates and recovers the granular additive contained in the drawn substance returned from the drawing pipe 10, returns the collected additive to the injection stirring tank 2, and discharges the separated sludge out of the system. It has a function. Reference numeral 13 denotes an inorganic flocculant supply means for supplying an inorganic flocculant to the rapid agitation tank 1, and reference numeral 14 denotes a polymer flocculant supply means for supplying a polymer flocculant to the rapid agitation tank 1.

  In the coagulation sedimentation apparatus configured as described above, a rectifying plate unit 20 is installed in the solid-liquid separation tank 4. The rectifying plate unit 20 is composed of a plurality of vertical rectifying plates 21 arranged at a predetermined interval in a direction transverse to the inside of the solid-liquid separation tank 4. It is designed to be distributed in a stream.

Next, the operation will be described.
To-be-treated water that has flowed into the rapid stirring tank 1 and the injection stirring tank 2 is supplied with inorganic flocculant and polymer flocculant from the inorganic flocculant supply means 13 and polymer flocculant supply means 14 and added to the stirrers 5 and 6. Then, it flows into the agglomeration reaction tank 4. In the agglomeration reaction tank 4, suspended substances contained in the water to be treated are agglomerated, thereby producing agglomerated floc. The effluent containing the floc floc (treated water) is transferred to the next solid-liquid separation tank 4 where it is separated into separated solids containing additives and treated water (separated water). Is done. Here, the water to be treated which has been transferred to the solid-liquid separation tank 4 becomes an upward flow from the bottom of the solid-liquid separation tank 4 and rises vertically between the vertical rectifying plates 21.

  In this way, the water to be treated transferred from the agglomeration reaction tank 3 to the solid-liquid separation tank 4 rises between the vertical rectifying plates 21 in the solid-liquid separation tank 4, thereby reducing the water area of the solid-liquid separation tank 4. The separated water can be evenly distributed over the entire surface without uneven flow, and the separated solids containing additives such as sand contained in the water to be treated settle in the vertical direction, so that the solid-liquid in the solid-liquid separation tank 4 Separation efficiency is increased. Moreover, the frequency | count that the separated solid adheres to the said baffle plate 21 is reduced significantly by separating the separated solid vertically as mentioned above.

  On the other hand, the separated solid matter settled at the bottom of the solid-liquid separation tank 4 is returned to the liquid cyclone 12 via the drawing pipe 10 by the drawing pump 11, and the additive contained in the separated solid matter is separated by this liquid cyclone 12. The additive is returned to the injection stirring tank 2.

  In the coagulation sedimentation apparatus shown in FIG. 1, the rapid stirring tank 1 is not necessarily required. In the case without the rapid stirring tank, the same effect can be obtained by injecting the inorganic flocculant directly into the raw water pipe and causing the reaction. Is obtained. Moreover, the additive separated by the liquid cyclone 12 may be returned to the agglomeration reaction tank (floc formation tank) 3 instead of the injection stirring tank 2 as necessary, and the same function and effect can be obtained in this case as well. Furthermore, the injection point of the polymer flocculant may be either the injection stirring tank 2 or the inlet of the agglomeration reaction tank 3 or just below the agitator of the agglomeration reaction tank 3, and may be dispensed as necessary. In this case, the same effect can be obtained.

Embodiment 2. FIG.
FIG. 2 is a schematic cross-sectional view showing a solid-liquid separation tank of a coagulation sedimentation apparatus according to Embodiment 2 of the present invention. In the second embodiment, a solid-liquid separation tank 4 in which a flat rectangular link belt type sludge scraping machine is installed is targeted, and a plurality of vertical parts having the same height are provided in the solid-liquid separation tank 4. The rectifying plate unit 20 is provided with the rectifying plate 21, and even if the rectifying plate unit 20 is provided, the same effects as those of the first embodiment can be obtained.

Embodiment 3 FIG.
3A and 3B are schematic cross-sectional views showing a modification of the current plate according to Embodiment 3 of the present invention.
In the third embodiment, a bent portion 21a or 21b is formed at the lower end portion of the rectifying plate 21 in the first and second embodiments, and the solid-liquid separation tank 4 is formed by the bent portion 21a or 21b. The flow rate of the upward flowing water is increased, or the upward flowing water is directed in the vertical direction to further increase the solid-liquid separation efficiency.

Embodiment 4 FIG.
FIG. 4 is a schematic cross-sectional view showing a solid-liquid separation tank of a coagulation sedimentation apparatus according to Embodiment 4 of the present invention. In the fourth embodiment, each rectifying plate 21 of the rectifying plate unit 20 installed in the solid-liquid separation tank 4 is transferred to the treated water from the agglomeration reaction tank 3 of the solid-liquid separation tank 4. It is formed so as to gradually become shorter from the side toward the separated water discharge side. In this case, the same effect as that of the first embodiment can be obtained.

Embodiment 5 FIG.
FIG. 5 is a schematic cross-sectional view showing a solid-liquid separation tank of a coagulation sedimentation apparatus according to Embodiment 5 of the present invention. In the fifth embodiment, each of the rectifying plates 21 of the rectifying plate unit 20 installed in the solid-liquid separation tank 4 is formed so that the respective heights are gradually shortened in the opposite direction to the case of the fourth embodiment. In this case, the same effect as that of the first embodiment can be obtained.

Embodiment 6 FIG.
FIG. 6 is a schematic cross-sectional view showing a solid-liquid separation tank of a coagulation sedimentation apparatus according to Embodiment 6 of the present invention. In the sixth embodiment, the rectifying plate unit 20 installed in the solid-liquid separation tank 4 is divided into a vertical rectifying plate 21A having a high height and a rectifying plate 21B having a short height, each having the same upper end. In this case, the same effect as that of the first embodiment can be obtained.
In the sixth embodiment, the rectifying plate 21A having a long height and the rectifying plate 21B having a short height are arranged at intervals of a plurality of (for example, every two or three) rectifying plates 21A having a long height, or A configuration may be adopted in which a plurality of rectifying plates 21B having a short height are alternately arranged (for example, every two or three sheets).

Embodiment 7 FIG.
FIG. 7 is a schematic plan view showing a solid-liquid separation tank of a coagulation sedimentation apparatus according to Embodiment 7 of the present invention. In each of the above-described embodiments, as the rectifying plate unit 20 installed in the solid-liquid separation tank 4, a plurality of vertical rectifying plates 21 or 21A, 21B are arranged at predetermined intervals in a direction transverse to the solid-liquid separation tank 4. However, in the seventh embodiment, a plurality of vertical rectifying plates 22 arranged at a predetermined interval in the direction transverse to the inside of the solid-liquid separation tank 4 and a predetermined direction in the longitudinal direction of the solid-liquid separation tank 4 are provided. A plurality of vertical rectifying plates 23 arranged at intervals are combined to constitute a planar grid-like rectifying plate unit 20 which is installed in the solid-liquid separation tank 4.

  According to the seventh embodiment, a plurality of vertical rectifying plates 22 and 23 are combined in the vertical and horizontal directions to form the planar grid-like rectifying plate unit 20, thereby forming between the rectifying plates 22 and 23. As the water to be treated rises vertically in the lattice-shaped space formed, the separated water can be more uniformly and efficiently distributed over the entire water area of the solid-liquid separation tank 4 and contained in the water to be treated. The separated solid containing the additive such as sand can be more efficiently settled in the vertical direction. Therefore, there is an effect that the solid-liquid separation efficiency in the solid-liquid separation tank 4 can be further increased.

Embodiment 8 FIG.
In the seventh embodiment, a plurality of vertical rectifying plates 22 and 23 are combined in the vertical and horizontal directions to form a planar grid-like rectifying plate unit 20, but the rectifying plate unit 20 is disposed in the solid-liquid separation tank 4. It may be configured by arranging a plurality of vertical rectifying plates at predetermined intervals only in a direction longitudinally cut along the longitudinal direction. Also in this case, substantially the same operational effects as those of the above embodiments can be obtained.

Embodiment 9 FIG.
FIG. 8 (A) is a schematic cross-sectional view showing a solid-liquid separation tank of a coagulation sedimentation apparatus according to Embodiment 9 of the present invention, and FIG. 8 (B) is a plan view of FIG. 8 (A).
In the ninth embodiment, in the solid-liquid separation tank 4, a plurality of vertical rectifying plates 21 having a planar annular shape with different diameters are arranged in a concentric annular shape to form a plurality of cylindrical rectifying plate units 20. It is composed. The solid-liquid separation tank 4 in which such a plurality of cylindrical rectifying plate units 20 are installed is not limited to the planar rectangular shape shown in FIG. 8B, but is a plane corresponding to the maximum outer diameter of the rectifying plate unit 20. A circular solid-liquid separation tank may be used. Thus, even when the solid-liquid separation tank 4 has a planar circular shape, the same effect as that of the first embodiment can be obtained by the rectifying plate unit 20 disposed in the tank.

Embodiment 10 FIG.
In the first to eighth embodiments, each of the rectifying plates 21, 21A, 21B, 22, 23 of the rectifying plate unit 20 installed in the solid-liquid separation tank 4 is formed in a rectangular shape or a trapezoidal shape. Even in the case where the current plate 21 or 21A, 21B, 22, 23 is vertically arranged to constitute the current plate unit 20, the same effects as those of the above embodiment can be obtained.

Embodiment 11 FIG.
In the eleventh embodiment, the rectifying plates 21 and 21A, 21B, 22, and 23 described in the respective embodiments are subjected to antibacterial treatment, and the rectifying plates 21 and 21A, 21B, 22, 23 corrosion or the like can be prevented. As the antibacterial treatment, an antibacterial material such as silver, copper, or nickel is mixed with the current plate material, or the current plate 21 and 21A, 21B, 22, 23 are coated with the above antibacterial material. Either may be sufficient.

In each of the above embodiments, a sludge scraper is installed in the solid-liquid separation tank 4, and the sludge scraper is known as a sewer technology such as a link belt type and a central drive type. In any case, the same effect can be obtained by applying the current plate having the shape described in each of the above embodiments.
In the rectifying plate unit 20 according to each of the above embodiments, each of the rectifying plates 21, 21A, 21B, 22, 23 is required to have a height of at least about 15 cm, and a height of at least 100 cm. In any case, sufficient effects similar to those described in the respective embodiments can be obtained. 1 to 5 and FIG. 8, the mutual distance between the rectifying plates 21A and 21B in FIG. 6, the mutual distance between the rectifying plates 22 and the mutual distance between the rectifying plates 23 in FIG. The distance may be 100 cm, but it is preferable that the distance is 7 cm to 30 cm as desired. When the distance between the rectifying plates is set to 10 cm in the actual example, the same effects as those of the above embodiments are obtained.

It is sectional drawing of the coagulation sedimentation apparatus by Embodiment 1 of this invention. It is a schematic sectional drawing which shows the solid-liquid separation tank of the coagulation sedimentation apparatus by Embodiment 2 of this invention. 3 (A) and 3 (B) are schematic cross-sectional views showing a modification of the current plate according to Embodiment 3 of the present invention. It is a schematic sectional drawing which shows the solid-liquid separation tank of the coagulation sedimentation apparatus by Embodiment 4 of this invention. It is a schematic sectional drawing which shows the solid-liquid separation tank of the coagulation sedimentation apparatus by Embodiment 5 of this invention. It is a schematic sectional drawing which shows the solid-liquid separation tank of the coagulation sedimentation apparatus by Embodiment 6 of this invention. It is a schematic plan view which shows the solid-liquid separation tank of the coagulation sedimentation apparatus by Embodiment 7 of this invention. FIG. 8 (A) is a schematic cross-sectional view showing a solid-liquid separation tank of a coagulation sedimentation apparatus according to Embodiment 9 of the present invention, and FIG. 8 (B) is a plan view of FIG. 8 (A).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rapid stirring tank 2 Injection | pouring stirring tank 3 Aggregation reaction tank 4 Solid-liquid separation tank 5, 6, 7 Stirrer 8 Sludge scraping machine 9 Motor 10 Pull-out piping 11 Pull-out pump 12 Liquid cyclone (additive supply means)
13 Inorganic flocculant supply means 14 Polymer flocculant supply means 20 Current plate units 21, 21A, 21B, 22, 23 Current plates 21a, 21b Bending portions

Claims (1)

An agglomeration reaction tank for aggregating suspended substances in the water to be treated, an additive supply means for supplying an insoluble particulate additive to the water to be treated, and a solid-liquid separation for separating outflow water from the agglomeration reaction tank In a coagulation sedimentation apparatus equipped with a separation tank,
A coagulation sedimentation apparatus characterized in that a rectifying plate unit comprising a plurality of vertical rectifying plates is installed in the solid-liquid separation tank.

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