JP7056824B2 - Solid-liquid separator - Google Patents

Description

The present invention relates to a solid-liquid separation device.

Generally, as one of the means for wastewater treatment, a solid-liquid separation treatment for removing impurities such as solid matter in wastewater is performed.
As such a solid-liquid separation treatment, a treatment using a solid-liquid separation device that performs coagulation-precipitation for coagulating and precipitating impurities such as organic substances and suspended solids by adding a coagulant to wastewater is performed. Can be mentioned. For example, a solid-liquid separator equipped with a floc zone type (sometimes called "sludge blanket type" or "flock blanket type") coagulation sedimentation tank in which an inner cylinder for receiving water to be treated is arranged in the settling tank. It has been known.

Patent Document 1 describes a coagulation-sedimentation treatment apparatus that forms a floc blanket layer in a settling tank by injecting an inorganic coagulant and an organic polymer coagulant into raw water (water to be treated). Further, in Patent Document 1, the injection amount of the inorganic flocculant and the organic polymer flocculant is determined by using the measured values by various measuring instruments (raw water flow meter, interface meter, turbidity meter) provided in the coagulation sedimentation treatment apparatus. A method for controlling chemical injection to determine and inject an inorganic flocculant and an organic polymer flocculant into raw water is described.

Japanese Unexamined Patent Publication No. 2-261505

In the coagulation sedimentation treatment apparatus described in Patent Document 1, a turbidity meter is provided at the upper end of the treated water layer formed above the floc blanket layer in the settling tank. In this way, the turbidity is measured at the upper end of the treated water layer formed above the settling tank, and the injection amount of the inorganic flocculant and the organic polymer flocculant is determined based on the measured values. When performing chemical injection control in which a flocculant and an organic polymer flocculant are injected, the turbidity that is judged to be the level at which the flocculant needs to be added has been detected in the treated water layer, so the quality of the treated water has already deteriorated. Has begun, and as a result, there is a problem that the injection of the flocculant is not in time. Therefore, it is required to immediately detect and deal with the deterioration tendency of the processing in the solid-liquid separator.

An object of the present invention is to provide a solid-liquid separation device that can immediately detect a deterioration tendency of treatment and maintain good quality of treated water in a solid-liquid separation device that captures solid matter in wastewater. be.

As a result of diligent studies on the above problems, the present inventor has a water quality detection unit near the interface of the clear layer composed of the treated water formed on the sludge blanket portion and the upper part of the sludge blanket portion in the solid-liquid separation device provided with the sludge blanket portion. The present invention has been completed by finding that it is possible to quickly detect the deterioration tendency of the treatment by providing the above.
That is, the present invention is the following solid-liquid separation device.

The solid-liquid separation device of the present invention for solving the above problems is a solid-liquid separation device that separates solids in the water to be treated into solids and liquids, and captures the introduced solids in the water to be treated as flocs. A sludge blanket unit having a floc growth zone to be grown and a separation zone for separating solid matter and treated water formed above the floc growth zone, and a water quality detecting unit for detecting the water quality of the treated water are provided to detect water quality. The portion is characterized in that it is arranged in a region of 50% or less of the vertical height from the interface to the water surface of the treated water with reference to the interface between the sludge blanket portion and the treated water.
In the solid-liquid separation device of the present invention, in the solid-liquid separation device having a sludge blanket portion, a water quality detection unit is provided near the interface between the sludge blanket portion and the clear layer made of treated water formed above the sludge blanket portion. As a result, it is possible to quickly detect the deterioration tendency of the treatment in the solid-liquid separation device, and it is possible to take measures to maintain good water quality of the treated water.

Further, one embodiment of the solid-liquid separation device of the present invention is characterized in that the water quality detection unit is arranged between 50 and 500 mm above the interface.
According to this feature, it becomes possible to detect the deterioration tendency of the processing in the sludge blanket portion with higher accuracy.

Further, as one embodiment of the solid-liquid separation device of the present invention, the water quality detection unit is characterized by being a turbidity meter.
According to this feature, it is possible to obtain information on the aggregated state of flocs as information for determining the deterioration tendency of the treatment in the sludge blanket portion.

Further, as one embodiment of the solid-liquid separation device of the present invention, the water quality detection unit is characterized in that the height in the vertical direction is adjustable.
According to this feature, the water quality detection unit can be arranged at an appropriate position according to the height and interface state of the interface between the sludge blanket portion and the clear layer, and highly accurate detection becomes possible.

Further, one embodiment of the solid-liquid separation device of the present invention is characterized in that a control unit for controlling the state of the sludge blanket unit is provided based on the result detected by the water quality detection unit.
According to this feature, the treatment capacity can be improved and the water quality of the treated water can be kept good by controlling the state of the sludge blanket portion based on the information related to the deterioration tendency of the treatment obtained by the water quality detection unit. ..

Further, as one embodiment of the solid-liquid separation device of the present invention, the control unit is characterized in that the amount of the flocculant added to the water to be treated or the flow rate of the water to be treated is controlled.
According to this feature, the treatment capacity in the sludge blanket portion can be improved, and the water quality of the treated water can be kept good.

According to the present invention, in a solid-liquid separation device that captures solid matter in wastewater, it is possible to provide a solid-liquid separation device that can immediately detect a deterioration tendency of treatment and maintain good water quality of treated water. ..

It is a schematic explanatory drawing of the solid-liquid separation apparatus which concerns on 1st Embodiment of this invention. It is a schematic explanatory drawing of the solid-liquid separation apparatus which concerns on 2nd Embodiment of this invention. It is a schematic explanatory drawing of the solid-liquid separation apparatus which concerns on 3rd Embodiment of this invention.

The solid-liquid separation device of the present invention is used for treating water to be treated containing solid matter. In particular, it is suitably used for a coagulation-precipitation treatment in which a coagulant is added to water to be treated to coagulate and precipitate organic substances and the like for separation.

Hereinafter, embodiments of the solid-liquid separator according to the present invention will be described in detail with reference to the drawings.
The solid-liquid separation device described in the following embodiment will be described by taking a coagulation sedimentation device as an example. However, the following embodiments are merely exemplified for explaining the solid-liquid separation device according to the present invention, and the solid-liquid separation device according to the present invention is not limited to the coagulation sedimentation device.

[First Embodiment]
FIG. 1 is a schematic explanatory view of the solid-liquid separation device 100 according to the first embodiment of the present invention.
The solid-liquid separation device 100 according to this embodiment has a so-called sludge blanket type coagulation sedimentation tank. Generally, in a sludge blanket type coagulation sedimentation tank, a fluidized bed of agglomerated flocs due to an ascending water flow is formed in the tank, and newly generated flocs are passed 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 is increased. As a result, the water to be treated introduced into the sludge blanket type coagulation sedimentation tank is separated into treated water and sludge, and each is discharged to the outside of the tank. Hereinafter, flocs may be referred to as aggregated flocs, sludge, and solids.

As shown in FIG. 1, in the solid-liquid separation device 100 according to the present embodiment, the water to be treated introduction unit 2 for introducing the water to be treated W and the solid matter in the water to be treated W are introduced into the coagulation and settling tank 1. It includes a sludge blanket unit 3 that captures and separates the solid matter and the treated water W1, a water quality detecting unit 4 of the treated water W1, and a treated water discharge line L1 that discharges the treated water W1. The layer made of the treated water W1 above the sludge blanket portion 3 is referred to as a clarification layer C.
Further, the coagulation settling tank 1 has a concentration section 5 in which flocs aggregated by passing through the sludge blanket section 3 overflow the upper end of the sludge blanket section 3 and settle to the bottom of the coagulation settling tank 1 to concentrate. Then, a sludge discharge line L2 for discharging the settled flocs (sludge) to the outside of the system is provided in the concentrating unit 5. The sludge discharge line L2 may be provided with sludge treatment equipment for treating sludge.

The coagulation sedimentation tank 1 includes a bottomed cylindrical outer cylinder water tank 11 and a bottomed cylindrical inner cylinder water tank 12 having a smaller diameter and a smaller height than the outer cylinder water tank 11. As shown in FIG. 1, the inner cylinder water tank 12 is erected inside the outer cylinder water tank 11 so as to be concentric with the outer cylinder water tank 11. Further, the bottom of the inner cylinder water tank 12 is separated upward from the bottom of the outer cylinder water tank 11 by a predetermined length, and exhibits a double water tank structure. Further, a center shaft 13 that is rotationally driven by a motor M is arranged on the axis L of the outer cylinder water tank 11 and the inner cylinder water tank 12. The center shaft 13 is connected to the bottom of the inner cylinder water tank 12 by a rotary joint 14. The outer cylinder water tank 11 and the inner cylinder water tank 12 are not limited to a cylindrical shape, and may be a square tubular shape.

The water to be treated introduction unit 2 has an introduction pipe 21 for introducing the water to be treated W into the coagulation sedimentation tank 1 and a feed pipe for supplying the water to be treated W introduced from the introduction pipe 21 into the inner cylinder water tank 12. 22 is provided. As shown in FIG. 1, the introduction pipe 21 penetrates the side wall of the outer cylinder water tank 11 and protrudes to the outside of the tank, and is connected to the supply source of the water to be treated W. Further, the feed pipe 22 is connected to the introduction pipe 21 so as to allow water to pass through, and is provided so as to surround the center shaft 13 on the outside of the center shaft 13. In the solid-liquid separation device of the present embodiment, the axes of the outer cylinder water tank 11, the inner cylinder water tank 12, the center shaft 13, and the feed pipe 22 all have a common axis L.

The feed pipe 22 is divided into an upper portion 22a and a lower portion 22b in the vertical direction, and the upper portion and the lower portion are connected by a rotary joint 23 having a labyrinth structure or the like. The introduction pipe 21 is connected to the side surface of the upper portion 22a of the feed pipe 22, and the distribution pipe 24 is provided in the lower portion 22b of the feed pipe 22. The distribution pipe 24 is arranged in the lower part of the inner cylinder water tank 12, and a plurality of water discharge ports 24a to be treated are formed. The lower part of the feed pipe 22 rotates with the rotation of the center shaft 13, and at this time, the distribution pipe 24 rotates with the water discharge port 24a to be treated facing the bottom side of the inner cylinder water tank 12. The upper end of the feed pipe 22 may be closed or may be open upward.

The water to be treated W introduced from the water to be treated water introduction unit 2 is wastewater containing a solid substance, for example, organic wastewater mixed with a flocculant. In the present embodiment, in order to mix the organic wastewater and the flocculant, an example of connecting the flocculant supply line L3 for supplying the flocculant to the introduction pipe 21 is illustrated in FIG. Not limited. For example, as will be described later, the water to be treated W obtained by mixing the coagulant with the raw water W0 in advance on the upstream side of the coagulation settling tank 1 may be supplied to the introduction pipe 21.

Examples of the coagulant to be mixed include an inorganic coagulant and an organic polymer coagulant. The flocculant may be an inorganic flocculant or an organic polymer flocculant alone, or may be a combination of the inorganic flocculant and the organic polymer flocculant. When the inorganic flocculant and the organic polymer flocculant are used in combination, it is preferable to add the inorganic flocculant and the organic polymer aggregate to the water W to be treated in this order. This enables stable floc formation.
Specific examples of the flocculant include, for example, Al-based inorganic flocculants such as sulfate band and PAC, and Fe-based inorganic flocculants such as polyiron sulfate. Alternatively, crystals can be formed by adding a pH adjuster using an alkali such as NaOH, Ca (OH) ₂ or an acid such as H ₂ SO ₄ , HCl, a Ca, Al, Fe-based compound, or an oxidizing agent / reducing agent. It may be deposited. Examples of the organic polymer flocculant include cationic polymer flocculants such as polyaminoalkylmethacrylate, polyethyleneimine, polydialylammonium halide, chitosan, and urea-formalin resin, sodium polyacrylate, and polyacrylamide partial hydrolyzate. Anionic polymer flocculants such as partially sulfomethylated polyacrylamide, poly (2-acrylamide) -2-methylpropane sulfate, nonionic polymer flocculants such as polyacrylamide and polyethylene oxide, acrylamide, aminoalkylmethacrylate and acrylic acid. Examples thereof include an amphoteric polymer flocculant such as a copolymer of sodium.

The sludge blanket portion 3 introduces the treated water W containing a coagulant from the treated water introduction portion, grows the agglomerated flocs, and then separates the agglomerated flocs (solid matter) and the treated water W1.
The separated treated water W1 is discharged to the outside of the system from the treated water discharge line L1 provided in the upper part of the coagulation sedimentation tank 1. Further, the aggregated flocs overflowing from the upper end of the sludge blanket portion 3 settle in the concentrating portion 5 provided in the lower part of the sludge blanket portion 3, and pass through the sludge discharge line L2 provided in the bottom of the aggregated sedimentation tank 1. It is discharged to the outside of the system.

As shown in FIG. 1, the sludge blanket portion 3 in the present embodiment points to the inner region of the bottomed cylindrical inner cylinder water tank 12 in the coagulation sedimentation tank 1. The sludge blanket portion 3 has a flock growth zone Z1 and a separation zone Z2 formed above the flock growth zone. The floc growth zone Z1 forms a fluidized bed of aggregated flocs by the rising water flow of the water to be treated W flowing into the inner cylinder water tank 12 by the water introduction portion 2 to be treated. Further, the separation zone Z2 is for solid-liquid separation between the aggregated flocs (solid matter) and the treated water W1.

The water to be treated W containing the coagulant is uniformly ejected from the distribution pipe 24 of the water introduction portion in the inner cylinder water tank 12 to the lower part in the inner cylinder water tank 12, and the stirring force, shearing force, etc. of the ejected water flow are uniformly ejected. Is mixed to form flocs. The flocs formed in the inner cylinder water tank 12 are deposited on the bottom of the inner cylinder water tank 12, and the fluidized bed is formed in the floc growth zone Z1 by the water to be treated W further supplied. The small flocs contained in the water to be treated W come into contact with and trapped in the flocs generated earlier in the process of ascending the fluidized bed, so that the particle size of the flocs grows large. In this way, the water to be treated W grows flocs while rising in the flocs growth zone Z1.

Here, since the specific gravity of the flocs is larger than that of water, the flocs tend to accumulate at the bottom of the flocs growth zone Z1, but increase due to the continuous supply of the water to be treated W. In the process in which the water to be treated W rises in the floc growth zone Z1, the flocs in the water to be treated W grow to be larger and heavier, so that they do not rise when they grow to a certain degree. Therefore, as shown in FIG. 1, larger and heavier flocs are gathered in the upper part of the inner cylinder water tank 12, and the ascending force due to the ascending flow of the water to be treated W and the sedimentation property (self-weight) of the flocs are in an equilibrium state. As a result, a virtual boundary layer K in which the floc concentration changes discontinuously is formed. Here, the virtual boundary layer K and the vicinity below it are referred to as a separation zone Z2. Flock is retained in a high concentration in the separation zone Z2. Further, a part of the flocs collected in the separation zone Z2 overflows from the upper end edge of the inner cylinder water tank 12 to the outer cylinder water tank 11 side by the fluidized bed of the water to be treated W. Since the overflowed aggregate flocs have a higher specific gravity than water, they naturally settle toward the concentrating portion 5 at the bottom of the outer cylinder water tank 11. The aggregated flocs that have settled and accumulated in the concentrating unit 5 are concentrated to become concentrated sludge, and are discharged from the sludge discharge line L2 provided at the bottom of the outer cylinder water tank 11.

Further, as shown in FIG. 1, the treated water that has passed through the sludge blanket portion 3 rises due to the ascending flow of the water to be treated W, and the layer of the treated water W1 (clear layer C) is above the sludge blanket portion 3. Is formed. That is, the virtual boundary layer K is formed at the boundary between the clear layer C and the sludge blanket portion 3. The treated water W1 in the clarification layer C is discharged to the outside of the tank via the treated water discharge line L1 provided in the upper part of the outer cylinder water tank 11.

On the other hand, the concentrated sludge accumulated in the concentrating unit 5 is scraped to the center of the bottom surface of the outer cylinder water tank 11 provided with the sludge discharge line L2 by the concentrated sludge scraping machine 51 provided at the lower end of the center shaft 13. The concentrated sludge scraping machine 51 is not particularly limited as long as it has a structure that rotates with the rotation of the center shaft 13 and can scrape the concentrated sludge to the central portion of the bottom surface of the outer cylinder water tank 11. For example, as shown in FIG. 1, in addition to the one provided with the scraping member perpendicular to the center shaft 13, a plurality of scraping members may be provided on the support perpendicularly intersecting the center shaft 13. The scraping member having a curved surface may be provided on the center shaft 13 so as to form an S shape when viewed from above the tank.

The water quality detection unit 4 is for measuring the water quality of the treated water W separated by the sludge blanket unit 3.
Examples of the water quality include turbidity, chromaticity, water temperature, pH, organic matter concentration, and the like. Examples of the detector for detecting the measurement target include a turbidity meter, a chromaticity meter, a water temperature meter, a pH meter, a COD meter, a BOD meter, a TOD meter, and a TOC meter.
As the water quality detecting unit 4 in the present embodiment, it is particularly preferable to use a turbidity meter that detects turbidity in order to obtain information on the aggregated state of flocs in the sludge blanket unit 3 that greatly affects the treatment status. As the turbidity meter, use a detector based on optical measurement by surface scattered light method, transmitted scattered light method, transmitted scattering comparison method, etc., and image analysis that analyzes the aggregated state of flocs using camera images. Can be done.

Further, the water quality detection unit 4 measures the water quality of the treated water in the vicinity of the separation zone Z2 in the sludge blanket unit 3. As a result, it is possible to obtain information for determining the progress state of the processing in the sludge blanket unit 3, and it is possible to quickly detect the deterioration tendency of the processing. Therefore, it is preferable that the water quality detection unit 4 is provided in a region of 50% or less of the vertical height of the clear layer C to the water surface with reference to the interface between the virtual boundary layer K and the clear layer C of the sludge blanket unit 3. It is particularly preferable to provide it in an area of 20% or less.
On the other hand, if the water quality detection unit 4 is arranged in a state where it is substantially in contact with the interface between the virtual boundary layer K of the sludge blanket portion 3 and the clear layer C, if the interface fluctuates even a little, the virtual boundary layer K of the sludge blanket portion 3 It is conceivable that the contained high-concentration flocs directly enter the detector of the water quality detector 4. At this time, there is a high possibility that the measurable range of the detector will be exceeded and detection will not be possible. Therefore, it is preferable to install the water quality detection unit 4 in a region above the height of 50 mm or more with reference to the interface between the virtual boundary layer K and the clarification layer C of the sludge blanket unit 3. Further, from the viewpoint of detecting the deterioration tendency of the treatment in the sludge blanket portion 3, the upper limit position of the installation of the water quality detection unit 4 is 500 mm or less in height from the interface between the virtual boundary layer K and the clear layer C of the sludge blanket portion 3. It is preferable to use the area of.

As a specific example of water quality detection, a case where a turbidity meter is used as the water quality detection unit 4 will be shown. When a turbidity meter is provided in a region 200 mm above the interface between the virtual boundary layer K and the clarification layer C of the sludge blanket portion 3, the measured value of the turbidity meter is several hundred mg / L under normal processing conditions. However, when the measured value of the turbidity meter exceeds 1000 mg / L, it can be considered that the floc aggregation is insufficient and the treatment efficiency is lowered. When the turbidity meter came into contact with the virtual boundary layer K of the sludge blanket portion 3, the measured value of the turbidity meter exceeded the measurable range (> 50,000 mg / L) and could not be detected.

Further, the water quality detection unit 4 is arranged so that the height in the vertical direction can be adjusted. The height of the interface between the virtual boundary layer K and the clear layer C of the sludge blanket portion 3 changes depending on the treatment conditions. Therefore, it is preferable to adjust the height of the water quality detection unit 4 according to the change in the height of the interface.
The means for adjusting the height of the water quality detection unit 4 is not particularly limited. For example, the string-shaped hanging support 41 such as a thread or a chain is directly attached to the detector used as the water quality detector 4, or the hanging support 41 is attached to the water-permeable container containing the detector. The height of the water quality detection unit 4 can be adjusted by manually or automatically changing the length of the suspension support 41.
Further, an interface meter for detecting the interface between the virtual boundary layer K and the clear layer C of the sludge blanket unit 3 is provided in the coagulation sedimentation tank 1 of the present embodiment, and the water quality detection unit 4 is provided according to the measurement result of the interface meter. The height may be adjustable (not shown). This enables highly accurate detection.

As described above, in the solid-liquid separation device 100 of the present embodiment, the water quality detection unit 4 is provided in a specific range in the vicinity of the interface between the virtual boundary layer K and the clear layer C of the sludge blanket unit 3, so that the solid-liquid is solid-liquid. It is possible to quickly detect the deterioration tendency of the processing in the separation device 100. This makes it possible to take measures to maintain good water quality of the treated water before the water quality of the treated water deteriorates.

[Second Embodiment]
FIG. 2 is a schematic explanatory view of the solid-liquid separation device 101 according to the second embodiment of the present invention.
As shown in FIG. 2, the solid-liquid separation device 101 according to the present embodiment is provided with a reaction tank 6 on the upstream side of the coagulation sedimentation tank 1 in the first embodiment, and a coagulant for adding a coagulant to the reaction tank 6. The addition means 7 is provided. Further, a control unit 8 for controlling the flocculant addition means 7 is provided based on the measurement result of the water quality detection unit 4.
Of the configurations of the solid-liquid separation device 101 in the present embodiment, the same as the configuration of the solid-liquid separation device 100 of the first embodiment will be omitted.

In the reaction tank 6, the raw water W0 is introduced and the coagulant is added by the coagulant adding means 7. As a result, the treated water from the reaction tank 6 is supplied to the coagulation sedimentation tank 1 via the introduction pipe 21 as the water to be treated W containing the solid matter.
The reaction tank 6 is composed of one or a plurality of tanks. For example, as shown in FIG. 2, two tanks, a first reaction tank 61 and a second reaction tank 62, are provided, and the flocculant addition means 71 is provided for each. , 72 shall be provided. At this time, the inorganic coagulant is added to the first reaction tank 61 by the coagulant adding means 71. On the other hand, the organic polymer flocculant is added to the second reaction tank 62 by the flocculant addition means 72. This makes it possible to form stable agglomerated flocs in the water to be treated W to be introduced into the agglomeration settling tank 1.
The reaction tank 6 may be provided with a stirring mechanism such as a stirrer. This makes it possible to increase the mixing efficiency of the raw water and the coagulant and improve the coagulation effect.

The control unit 8 is for controlling the amount of the coagulant added by the coagulant addition means 7 based on the measurement result of the water quality detection unit 4. For example, when it is found from the measurement results of the water quality detection unit 4 that the floc aggregation state in the sludge blanket unit 3 tends to deteriorate, the amount of the flocculant added is increased.
The means for controlling the amount of the flocculant added is not particularly limited. For example, the one that controls the opening and closing of the valve provided in the coagulant addition means 7 and the like can be mentioned.

As described above, in the solid-liquid separation device 101 of the present embodiment, the measurement result of the water quality detection unit 4 provided in the specific range of the interface vicinity region between the virtual boundary layer K and the clarification layer C of the sludge blanket unit 3 Based on this, the amount of the flocculant added is controlled. This makes it possible to maintain good quality of the treated water before the quality of the treated water deteriorates.

[Third Embodiment]
FIG. 3 is a schematic explanatory view of the solid-liquid separation device 102 according to the third embodiment of the present invention.
As shown in FIG. 3, the solid-liquid separation device 102 according to the present embodiment is provided with a flow rate adjusting mechanism 9 in the introduction pipe 21 of the coagulation sedimentation tank 1 in the first embodiment. Further, a control unit 80 for controlling the flow rate adjusting mechanism 9 is provided based on the measurement result of the water quality detection unit 4.
Of the configurations of the solid-liquid separation device 102 in the present embodiment, the same as the configuration of the solid-liquid separation device 100 of the first embodiment or the solid-liquid separation device 101 of the second embodiment will be omitted. do.

The flow rate adjusting mechanism 9 is for adjusting the flow rate of the water to be treated W introduced from the introduction pipe 21 into the coagulation sedimentation tank 1. For example, a flow rate control valve or a valve may be mentioned. Further, the place where the flow rate adjusting mechanism 9 is arranged is not limited to the introduction pipe 21. For example, when the reaction tank 6 is provided on the upstream side of the coagulation sedimentation tank 1, the flow rate adjusting mechanism 9 may be provided on the discharge line from the reaction tank 6.

The control unit 80 is for controlling the amount of water to be treated W added by the flow rate adjusting mechanism 9 based on the measurement result of the water quality detection unit 4. For example, when it is confirmed from the measurement results of the water quality detection unit 4 that the floc aggregation state in the sludge blanket unit 3 tends to deteriorate, the water to be treated W introduced into the aggregation sedimentation tank 1 by the flow rate adjusting mechanism 9. Reduce the flow rate.

As described above, in the solid-liquid separation device 102 of the present embodiment, the measurement result of the water quality detection unit 4 provided in the specific range of the interface vicinity region between the virtual boundary layer K and the clarification layer C of the sludge blanket unit 3 Based on this, the flow rate of the water to be treated W to be introduced into the coagulation sedimentation tank 1 is controlled. This makes it possible to maintain good quality of the treated water before the quality of the treated water deteriorates.

The above-described embodiment shows an example of a solid-liquid separation device. The solid-liquid separation device according to the present invention is not limited to the above-described embodiment, and the solid-liquid separation device according to the above-described embodiment may be modified without changing the gist described in the claims.

For example, the solid-liquid separation device of the present embodiment uses a double-structured coagulation-sedimentation tank with an outer cylinder water tank and an inner cylinder water tank, but has a configuration for forming an interface between a sludge blanket portion and a clear layer. If there is, it is not particularly limited. For example, a bottom plate horizontally arranged in the coagulation settling tank and a side wall extending upward from a part of the outer peripheral end of the bottom plate and connected to the peripheral wall of the coagulation settling tank are provided above and on the side wall of the bottom plate. A fluidized bed (sludge blanket part) of floc is formed in the section defined on the inner peripheral side of the water quality detection unit near the interface between the sludge blanket part and the clear layer formed above the sludge blanket part. May be provided.

Further, the solid-liquid separation device of the present embodiment uses a feed pipe as the water to be treated introduction portion, but is not particularly limited as long as the water to be treated can be introduced into the tank. Without providing the feed pipe shown in this embodiment, the introduction pipe inserts the tank peripheral wall of the outer cylinder water tank and the tank peripheral wall of the inner cylinder water tank to directly introduce the water to be treated into the inner cylinder water tank. May be good. This makes it possible to reduce the number of parts of the device.

Further, in the solid-liquid separation device of the present embodiment, a part of the sludge discharged from the sludge discharge line may be returned to the coagulation sedimentation tank and circulated. This makes it possible to supply a seed crystal as a nucleus in which flocs grow to the coagulation sedimentation tank. By growing flocs as large particles with seed crystals as nuclei, the solid-liquid separability between solids and treated water in the coagulation sedimentation tank is improved.

Further, the solid-liquid separation device of the present embodiment may be provided with a floc extraction portion in the sludge blanket portion and returned to the coagulation settling tank or the reaction tank provided upstream of the coagulation settling tank. As a result, the flocs grown in the sludge blanket section can be circulated, so that the residence time for growing good flocs and the rising flow velocity of the water to be treated can be maintained without increasing the capacity of the sludge blanket section. It is possible to obtain clear treated water.

The solid-liquid separation device of the present invention is used for treating water to be treated containing solid matter. In particular, the solid-liquid separation device of the present invention is suitably used as a coagulation-sedimentation device that performs a coagulation-sedimentation treatment by adding a coagulant to the water to be treated.

100, 101, 102 Solid-liquid separator, 1 coagulation settling tank, 11 outer cylinder water tank, 12 inner cylinder water tank, 13 center shaft, 14 rotary joint, 2 treated water introduction part, 21 introduction pipe, 22 feed pipe, 22a upper part , 22b lower part, 23 rotary joint, 24 distribution pipe, 24a treated water discharge port, 3 sludge blanket part, 4 water quality detection part, 41 hanging support, 5 concentration part, 51 concentration sludge scraper, 6,61, 62 Reaction tank, 7,71,72 Coagulant addition means, 8,80 Control unit, 9 Flow control mechanism, L1 treated water discharge line, L2 sludge discharge line, L3 coagulant supply line, C clarification layer, K virtual boundary layer , L-axis, M motor, W treated water, W0 raw water, W1 treated water, Z1 floc growth zone, Z2 separation zone

Claims (5)

A solid-liquid separation device that separates solids in the water to be treated.
The floc growth zone , which is placed in the coagulation sedimentation tank and captures the introduced solid matter in the water to be treated and grows as flocs, and the solid matter formed above the floc growth zone and the treated water are separated. A sludge blanket section with a separation zone and
It is equipped with a water quality detection unit that detects the water quality of the treated water.
The water quality detection unit is characterized in that it is arranged in a region of 50% or less of the vertical height from the interface to the water surface of the treated water with reference to the interface between the sludge blanket portion and the treated water. , Solid-liquid separator. The solid-liquid separation device according to claim 1, wherein the water quality detection unit is arranged between 50 and 500 mm above the interface. The solid-liquid separation device according to claim 1 or 2, wherein the water quality detection unit is a turbidity meter. The solid-liquid separation device according to any one of claims 1 to 3, wherein the water quality detecting unit is arranged so that the height in the vertical direction can be adjusted. Any of claims 1 to 4, wherein a control unit for controlling the amount of the flocculant added to the water to be treated or the flow rate of the water to be treated is provided based on the result detected by the water quality detection unit. The solid-liquid separation device according to paragraph 1.

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