Coagulation and sedimentation apparatus and maturation tank for coagulation and sedimentation apparatus

Abstract

To provide means to contribute to the improvement of the aging effect in the aging step of bonded floc.SOLUTION: There is provided an aging tank 20 used for a coagulation and sedimentation device that separates raw water A into sludge C and treated water B. The aging tank 20 that has a function of aging bonded floc in which floc in inflow water and a sedimentation accelerator G are bonded to each other by adding a polymer coagulant F and the sedimentation accelerator G to the inflow water including at least the raw water A and agitating them is formed of a plurality of divided tanks that allow the inflow water to sequentially pass therethrough. An agitation device that can be controlled independently is installed in each divided tank and the agitation force is adjusted individually to improve the aging effect of the bonded floc.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a flocculation sedimentation device for separating raw water into sludge and treated water by flocculation sedimentation in wastewater treatment such as construction work. and for coagulation and sedimentation apparatus Aging In the tank It relates to.

Background Art

[0002] As a flocculation sedimentation device for separating raw water into sludge and treated water by flocculation sedimentation, the applicant conceived the invention described in Patent Document 1 below. This flocculation sedimentation device includes at least a flocculation tank, an aging tank, a sedimentation tank, a circulation pump, a cyclone, a distribution tank, and a concentration tank, and each tank has the following functions. [1] Flocculation tank: An inorganic flocculant is added to the mixed water containing raw water and overflow water from the concentration tank, and the mixture is stirred and mixed to flocculate suspended substances. [2] Aging tank: A polymer flocculant and a sedimentation accelerator are added to the mixed water from the flocculation tank, and the mixture is stirred and mixed, so that the flocs in the mixed water and the sedimentation accelerator are combined to age the combined flocs. [3] Sedimentation tank: The combined flocs in the mixed water from the aging tank are sedimented to separate the mixed water into treated water and sediment slurry. [4] Circulation pump: At least the sediment slurry taken out from the sedimentation tank is supplied to the cyclone. [5] Cyclone: The sediment slurry supplied from the circulation pump is separated into separated slurry and sludge containing the sedimentation accelerator, and the sludge is supplied to the aging tank as part or all of the sedimentation accelerator, and the separated slurry is supplied to the distribution tank. [6] Distribution tank: The separated slurry from the cyclone is separated into discharge slurry and circulation slurry while removing air, the discharge slurry is supplied to the concentration tank, and the circulation slurry is supplied to the circulation pump together with the sediment slurry from the sedimentation tank. [7] Concentration tank: The discharge slurry from the distribution tank is retained for a predetermined time and concentrated, and then taken out as sludge, and the overflow is supplied to the flocculation tank as overflow water.

[0003] Thus, the coagulation and sedimentation apparatus, in separating treated water from raw water, includes at least a coagulation step for suspended solids, a maturation step for bound flocs, and a separation step for the precipitated slurry consisting of bound flocs. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 6725316 [Overview of the project] [Problems that the invention aims to solve]

[0005] One of the objectives of this invention is to provide a means that contributes to improving the maturation effect in the maturation process of bonded flocs. [Means for solving the problem]

[0006] The present invention, made to solve the above problems, is a maturation tank used in a coagulation and sedimentation apparatus that separates raw water into sludge and treated water, wherein the maturation tank is Inorganic flocculants were added. The maturation tank has the function of maturing bound flocs formed by the binding of flocs in the influent water with the settling accelerator by adding a polymer flocculant and a settling accelerator to the influent water which contains at least the raw water and stirring, and the maturation tank consists of a plurality of divided tanks through which the influent water passes sequentially, and each divided tank is provided with an independently controllable stirring device. Furthermore, a baffle is provided at the outlet of at least one of the plurality of divided tanks to circulate the downward flow produced by the stirring device. It is characterized by the following: Furthermore, the present invention may be configured such that the plurality of dividing tanks include at least a first dividing tank which promotes the formation of the bound flocs by adding the polymer flocculant and the settling accelerator to the influent water and stirring, and a second dividing tank which promotes the growth of the bound flocs by stirring the overflow water from the first dividing tank with a weaker force than the stirring in the first dividing tank. Furthermore, the present invention may be configured to provide a plurality of second dividing tanks, and to allow the overflow water from the first dividing tank to pass through each of the second dividing tanks in sequence. Furthermore, the present invention may also include a window in at least one of the plurality of divided tanks for visual inspection of the inside of the tank. 。

[0007] Furthermore, the present invention is a coagulation and sedimentation apparatus for separating raw water into sludge and treated water, comprising at least a coagulation tank, a maturation tank, a sedimentation tank, a first circulation pump, a first cyclone, a recovery tank, and a concentration tank, wherein the coagulation tank has the function of agitating and mixing the raw water, the overflow water from the concentration tank, and a mixed water containing at least an inorganic coagulant to coagulate suspended solids, the maturation tank has the function of maturing bound flocs formed by the binding of flocs in the mixed water with the sedimentation accelerator by adding a polymer coagulant and a sedimentation accelerator to the mixed water from the coagulation tank and agitating and mixing, the sedimentation tank has the function of settling the bound flocs in the mixed water from the maturation tank and separating the mixed water into treated water and a sedimented slurry, the first circulation pump has the function of supplying the sedimented slurry taken out from at least the sedimentation tank to the first cyclone, and the first cyclone is The system has the function of separating the sedimentation slurry supplied from the first circulation pump into a separation slurry and a muddy substance containing the sedimentation accelerator, supplying the muddy substance to the aging tank as part or all of the sedimentation accelerator, and supplying the separation slurry to the recovery tank; the recovery tank has the function of separating the separation slurry from the first cyclone into a recovery slurry and a muddy substance containing the sedimentation accelerator, supplying the muddy substance to the aging tank as part or all of the sedimentation accelerator, and supplying the recovery slurry to the thickening tank; the thickening tank has the function of allowing the recovery slurry from the recovery tank to remain for a predetermined time to thicken before removing it as sludge, and supplying the overflow as overflow water to the coagulation tank; and the aging tank consists of a plurality of divided tanks through which the mixed water from the coagulation tank passes sequentially, and each divided tank is equipped with an independently controllable stirring device. 。 Furthermore, the present invention is , theThe system further comprises a second circulation pump and a second cyclone, the second circulation pump having the function of supplying at least the sediment slurry removed from the sedimentation tank to the first cyclone and / or the second cyclone, the second cyclone having the function of separating the sediment slurry supplied from the second circulation pump into a separation slurry and a muddy substance containing the sedimentation accelerator, supplying the muddy substance to the maturation tank as part or all of the sedimentation accelerator, and supplying the separation slurry to the thickening tank, the thickening tank having the function of allowing the recovered slurry from the recovery tank and the separated slurry from the second cyclone to remain for a predetermined time to thicken before removing them as sludge, and supplying the overflow as overflow water to the coagulation tank. Furthermore, the present invention may be configured to further include a line mixer that pre-mixes an inorganic coagulant with carbon dioxide gas in the raw water sent to the coagulation tank. Furthermore, the present invention may be configured such that the plurality of dividing tanks include at least a first dividing tank which promotes the formation of the bound flocs by adding the polymer flocculant and the settling accelerator to the influent water and stirring, and a second dividing tank which promotes the growth of the bound flocs by stirring the overflow water from the first dividing tank with a weaker force than the stirring in the first dividing tank. Furthermore, the present invention may be configured to provide a plurality of second dividing tanks, and to allow the overflow water from the first dividing tank to pass through each of the second dividing tanks in sequence. Furthermore, in the present invention, a window for visually inspecting the inside of the tank may be provided in at least one of the plurality of divided tanks. Furthermore, in the present invention, a baffle may be provided at the outlet of at least one of the plurality of divided tanks to circulate the downward flow produced by the stirring device. [Effects of the Invention]

[0009] According to the present invention, at least one of the effects described below is achieved. (1) By configuring the maturation tank with multiple divided tanks and providing each divided tank with an independently controllable stirring device, it is possible to manage the stirring force in each divided tank to a level suitable for maturation of the bound flocs. (2) In the first dividing tank, which first receives the mixed water from the coagulation tank, the formation of bound flocs is promoted by increasing the collision opportunities between the flocs and the polymer flocculant and sedimentation accelerator through stirring at a relatively high rotational speed. In the second dividing tank, which receives the overflow water from the first dividing tank, the growth of bound flocs is promoted without destroying them by stirring with a weaker force than in the first dividing tank, thereby obtaining more mature bound flocs. (3) By providing a plurality of second separation tanks and causing the overflow water from the first separation tank to pass through each of the second separation tanks in sequence, the aging effect of the combined flocs can be enhanced more effectively. (4) By providing a window portion for visually observing the inside of at least one of the plurality of separation tanks constituting the aging tank, the aging state of the combined flocs can be appropriately confirmed, and the management of the stirring force (such as the rotation speed) can be appropriately adjusted. (5) By providing a baffle in at least one of the plurality of separation tanks constituting the aging tank, it is possible to prevent the combined flocs from flowing out to the next tank with insufficient aging due to the momentum of the water flow by the stirring device. (6) By providing a second circulation pump and a second cyclone in addition to the first circulation pump and the first cyclone, the amount of the precipitated slurry withdrawn from the sedimentation tank can be increased. Also, in preparation for the failure of the first circulation pump, the second circulation pump can be secured as a standby pump. (7) By providing a polymer flocculant addition function in the concentration tank, the concentration effect of the discharged slurry contained in the concentration tank can be enhanced more effectively. (8) By providing a line mixer for pre-mixing an inorganic flocculant and carbon dioxide gas with the raw water sent to the flocculation tank, the raw water in which the carbon dioxide gas and the inorganic flocculant are sufficiently mixed can be made to flow into the flocculation tank.

Brief Description of the Drawings

[0010] [Figure 1] Schematic diagram showing the overall configuration of the coagulation sedimentation apparatus according to Example 1. [Figure 2] Schematic diagram showing a partial configuration of the coagulation sedimentation apparatus according to Example 2. [Figure 3] Schematic diagram showing an arrangement example of the aging tank in the coagulation sedimentation apparatus according to Example 3.

Modes for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Examples

[0012] <1> Overall structure The coagulation and sedimentation apparatus according to the present invention is a device that separates raw water A into treated water B and sludge C. The coagulation and sedimentation apparatus shown in Figure 1 comprises, as its main components, at least a coagulation tank 10, a maturation tank 20, a sedimentation tank 30, a first circulation pump 40, a first cyclone 50, a recovery tank 60, and a concentration tank 70. The details of each component are described below.

[0013] <2> flocculation tank The coagulation tank 10 has the function of adding an inorganic coagulant E to a mixed water containing raw water A and overflow water from the concentration tank 70, and then stirring and mixing it using a stirring device installed inside the tank. The raw water A targeted in this invention includes various types of wastewater, such as wastewater generated during construction work (construction wastewater) and domestic wastewater. Details of the overflow water from the concentration tank 70 will be explained in the section on the concentration tank 70 below. The overflow of mixed water from the coagulation tank 10 is sent to the maturation tank 20 in the next process.

[0014] <2.1> Inorganic flocculants Inorganic coagulant D is an additive used to coagulate suspended solids in mixed water and generate fine flocs. As the inorganic flocculant D, for example, any one of polyaluminum chloride (PAC), ferric chloride, or ferric sulfate, or a mixture thereof, can be used. In this invention, the method of adding the inorganic coagulant D is not particularly limited. The inorganic coagulant D may be added in the line that sends the raw water A to the coagulation tank 10, or the inorganic coagulant D may be added directly to the coagulation tank 10.

[0015] <2.2> Mixing with carbon dioxide In this invention, a mechanism for mixing carbon dioxide E with raw water A may be provided. In this embodiment, a line supplying carbon dioxide E and a line supplying inorganic coagulant D are connected in the middle of the line that sends raw water A to the coagulation tank 10, and the raw water A mixed with carbon dioxide E and inorganic coagulant D is sent to the coagulation tank 10 using a line mixer. This configuration allows for the pre-mixing of raw water A, which contains carbon dioxide E and inorganic coagulant D, into the coagulation tank 10.

[0016] <2.3> Mechanism for adjusting overflow A height-adjustable weir (partition plate) may be provided at the outlet of the coagulation tank 10 (not shown). This configuration allows for adjustment so that the mixed water in the coagulation tank 10 overflows uniformly.

[0017] <3> Aging tank The maturation tank 20 has the function of maturing the fine flocs in the mixed water by adding a polymer flocculant F and a sedimentation accelerator G to the mixed water overflowing from the coagulation tank 10 and stirring and mixing them, thereby causing the fine flocs in the mixed water to bind with the sedimentation accelerator G.

[0018] <3.1> About each additive First, let me explain the additives used in the maturation tank 20.

[0019] <3.1.1> Polymer flocculants Polymer flocculant F is an additive used to bind the fine flocs generated in the flocculation tank 10 with the sedimentation accelerator G. As the polymer flocculant F, for example, nonionic, anionic, cationic, or amphoteric polymer flocculants F, or natural polymer flocculants F such as alginic acid, or mixtures thereof can be used.

[0020] <3.1.2> Settlement Accelerator The settling accelerator G is an additive that combines with the fine flocs generated in the coagulation tank 10 to obtain flocs with a higher specific gravity. As the settling accelerator G, granular materials such as sand can be used. The settling accelerator G added in the coagulation tank 10 may be newly prepared or separated again from the slurry (sedimented slurry) withdrawn from the sedimentation tank 30, which will be described later.

[0021] <3.1.3>Method of adding each additive In this embodiment, the sedimentation accelerator G is added to the mixed water overflowing from the coagulation tank 10 while it is being sent to the maturation tank 20, and the polymer coagulant F is added directly to the maturation tank 20. However, the present invention does not particularly limit the manner or order of addition of these additives.

[0022] <3.2> Structure of the aging tank Next, we will explain the configuration of the maturation tank 20. In this invention, the maturation tank 20 can be composed of a plurality of divided tanks. In this embodiment, the maturation tank 20 is composed of a total of four tanks, consisting of two types of divided tanks (one first divided tank 21 and three second divided tanks 22). The mixed water from the coagulation tank 10 is arranged in series in the following order: first divided tank 21, second divided tank 22a, second divided tank 22b, and second divided tank 22c.

[0023] <3.2.1> Stirring device Each divided tank is equipped with an independently controllable stirring device. Furthermore, at least one of the divided tanks may be provided with a window (not shown) for visually inspecting the state of the bonded flocs inside the tank. Furthermore, at least one of the dividing tanks may be equipped with a baffle 23 (water flow adjustment plate) (not shown) to prevent the bound flocs from flowing out to the next tank before they have fully matured due to the force of the water flow from the agitator. The details of each divided tank are described below.

[0024] <3.3> First dividing tank The first dividing tank 21 is a tank for forming bound flocs in the mixed water that has overflowed from the coagulation tank 10. More specifically, the first dividing tank 21 has the function of promoting the formation of bound flocs by adding a polymer flocculant F and a sedimentation accelerator G to the mixed water from the coagulation tank 10 and stirring it. The details of the polymer flocculant F and sedimentation accelerator G added in the first dividing tank 21 are as described above.

[0025] <3.3.1> Formation of binding flocs In the first divided tank 21, it is preferable to perform mixing and stirring with a relatively strong stirring force. The reason for this is that, in order to form bound flocs, it is preferable to increase the frequency of contact between the flocs in the mixed water and the polymer flocculant F and the settling accelerator G. The stirring force can be adjusted by adjusting the size of the stirring blades, adjusting the rotation speed, or switching the rotation method as appropriate, but generally, adjusting the rotation speed of the stirring blades is preferred. In this example, the rotation speed of the stirring blade in the first divided tank 21 is set to approximately 60 rpm. The overflow portion of the mixed water in the first dividing tank 21, where bound flocs have formed, is sent to the second dividing tank 22a.

[0026] <3.4> Second dividing tank The second dividing tank 22 is a tank for promoting the growth of bonded flocs. In this embodiment, three second division tanks 22 are connected in series, and the mixed water overflowing from the coagulation tank 10 passes through each of the second division tanks 22, with the final mixed water overflowing from the third second division tank 22c being sent to the sedimentation tank 30.

[0027] <3.4.1> Growth of binding flocs In the second divided tank 22, it is preferable to perform stirring with a weaker force than that performed in the first divided tank 21. The reason for this is to prevent the combined flocs formed in the first dividing tank 21 from being destroyed by the stirring device installed in the second dividing tank 22. As the bound flocs grow in the second dividing tank 22, they mature to a point where their specific gravity increases and they become more prone to sedimentation.

[0028] Furthermore, if multiple second dividing tanks 22 are provided, the system can be configured to gradually reduce the stirring force in the second dividing tanks 22 as the material is delivered in sequence. This configuration makes it possible to more efficiently suppress the breakdown of bound flocs that have grown through each of the second dividing tanks 22. In this embodiment, the rotation speeds of the stirring blades in the three second divided tanks 22a, 22b, and 22c through which the mixed water flows in sequence are set as follows. • First unit, second division tank 22a: approximately 50-40 [rpm] • Second split tank 22b: Approximately 40-30 [rpm] • Third unit, second division tank 22c: approximately 30-20 [rpm]

[0029] <4> Sedimentation tank The sedimentation tank 30 has the function of allowing bound flocs in the mixed water from the maturation tank 20 to settle, thereby separating the mixed water into treated water B and a precipitated slurry. As the bound flocs that have grown significantly in the maturation tank 20 settle at the bottom of the sedimentation tank 30, the mixed water is separated into a precipitate slurry consisting of the settled bound flocs in the sedimentation tank 30 and the supernatant, which is treated water B. At the bottom of the sedimentation tank 30, there is a means for scraping and collecting the sedimentation slurry, and a line for drawing out the collected sedimentation slurry.

[0030] <5> First circulation pump The first circulation pump 40 has the function of drawing the sedimentation slurry from the sedimentation tank 30 and sending it to the cyclone. The first circulation pump 40 can be any known pump.

[0031] <6> The first cyclone The first cyclone 50 has the function of removing muddy material from the sediment slurry supplied by the first circulation pump 40. The muddy substance is sludge mainly containing the settling accelerator G that was present in the sedimentation slurry. The first cyclone 50 can use a known separator or classifier. First, the first cyclone 50 separates the precipitated slurry supplied from the circulation pump into a separation slurry and a muddy substance through centrifugal force within its interior. The separated slurry is sent to the recovery tank 60. Furthermore, the separated muddy material can be supplied to the maturation tank 20 as part or all of the settling accelerator G.

[0032] <7> Recovery tank The recovery tank 60 has the function of temporarily receiving the separated slurry from the first cyclone 50 and supplying it to the concentration tank 70 as recovered slurry.

[0033] <7.1>Open space The recovery tank 60 has an open space that communicates with the space outside the tank. First, the recovery tank contains the slurry separated from the cyclone.

[0034] <7.2> Re-collection of muddy material Furthermore, the recovery tank 60 may be equipped with a line that allows for the re-recovery of muddy material remaining in the separation slurry and its supply to the maturation tank 20 as part or all of the settling accelerator G.

[0035] <8> concentration tank The concentration tank 70 has the function of retaining and concentrating the recovered slurry. First, the concentration tank 70 receives the recovered slurry from the recovery tank 60, allows it to remain there for a predetermined time, and concentrates the recovered slurry. The discharged slurry, concentrated in the thickening tank 70, is extracted as final sludge C from the bottom of the thickening tank 70 by a sludge pump or the like at an appropriate time and sent to the next process, dewatering treatment. Furthermore, the amount of recovered slurry extracted can be controlled by a sludge interface meter installed in the thickening tank 70. Therefore, the sludge C obtained by concentrating the recovered slurry is always dewatered in a highly concentrated state, which contributes to improving dewatering efficiency.

[0036] Furthermore, in this invention, the concentration tank 70 may also be provided with a function for adding a polymer flocculant F to the discharged slurry. By incorporating this function, the concentration effect of the recovered slurry can be further enhanced.

[0037] Furthermore, the overflow water from the recovered slurry contained in the thickening tank 70 is configured to be circulated back to the coagulation tank 10. The method of supplying overflow water circulated from the thickening tank 70 to the coagulation tank 10 is preferable if the overflow is configured to flow naturally, as this does not require any particular energy. [Examples]

[0038] <1> Overall structure Figure 2 shows the slurry flow from the sedimentation tank 30 onward in the sedimentation and coagulation apparatus according to Example 2 of the present invention. In this embodiment, in addition to the first circulation pump 40 and the first cyclone 50 described in Example 1, a second circulation pump 80 and a second cyclone 90 are further provided.

[0039] <2> Second circulation pump The second circulation pump 80 is connected in parallel with the first circulation pump 40 and has the function of supplying the sediment slurry removed from the sedimentation tank 30 to the first cyclone 50 and / or the second cyclone 90.

[0040] <3> The second cyclone The second cyclone 90 has the function of separating the sedimentation slurry supplied from the second circulation pump 80 into a separation slurry and a muddy substance containing the sedimentation accelerator G, similar to the first cyclone 50. The separated muddy material is supplied to the maturation tank 20 as part or all of the settling accelerator G, similar to the first cyclone 50, but unlike the first cyclone 50, the separated slurry is sent directly to the concentration tank 70.

[0041] <4> concentration tank With the above configuration, in the concentration tank 70 according to this embodiment, the sludge C is extracted in such a way that the recovered slurry sent from the recovery tank 60 also includes the separated slurry sent from the second cyclone 90.

[0042] <5> summary According to this embodiment, the first circulation pump 40 and the second circulation pump 80 can be operated simultaneously in accordance with the amount of slurry separated from the raw water A to increase the amount of slurry discharged, or the second circulation pump 80 can be used to supply the settled slurry to the first cyclone 50 in the event of a failure of the first circulation pump 40. [Examples]

[0043] Figure 3 shows an example layout of the flocculation tank 10, maturation tank 20, and sedimentation tank 30 in the sedimentation and flocculation apparatus according to Example 3 of the present invention.

[0044] <1> Overall structure In this embodiment, the entire apparatus is configured with equal width, and the four divided tanks constituting the aging tank 20 are arranged in a configuration of approximately two rows and two columns when viewed from above, with one first divided tank 21 and three second divided tanks 22 (22a, 22b, 22c). Of these, the third, second dividing tank 22c has a roughly L-shape when viewed from above, corresponding to the overall width of the sedimentation tank 30. Therefore, the mixed water overflowing from the coagulation tank 10 is sent to the sedimentation tank 30, flowing in a roughly S-shape when viewed from above, from the first dividing tank 21 to the final second dividing tank 22c.

[0045] <2> stirring blade The stirring blades (not shown) installed in each divided tank are configured to generate a downward flow in a right-hand rotation (clockwise in a plan view). This configuration allows the incoming mixed water to be guided to the bottom of the tank, enabling sufficient stirring within the tank.

[0046] <3> baffle Each divided tank outlet is equipped with a baffle 23 that is positioned to slope downward toward the front. By providing the baffle 23, the force of the downward flow generated by the stirring blades in each divided tank prevents the mixed water from flowing out to the next tank before the combined flocs have fully matured.

[0047] <4> Guidance waterway The third (final) second division tank 22c is provided with a guide channel to allow the mixed water to flow out to the entire width of the sedimentation tank 30. By tilting the bottom of the induction channel 24 at approximately 45°, the accumulation of bound flocs within the channel can be prevented. Furthermore, a baffle 23 is provided near the entrance of the induction channel 24, extending from the side wall of the second second division tank 22b. This baffle 23 prevents the mixed water that has overflowed from the second second division tank 22b to the third second division tank 22c from immediately flowing into the induction channel 24.

[0048] <5> Weir board A removable or height-adjustable weir plate 31 is provided at the boundary between the third, second dividing tank 22c and the sedimentation tank 30. By installing this weir plate 31, the mixed water flowing into the sedimentation tank 30 can be adjusted to become a uniform overflow.

[0049] <6> inclined plate Multiple inclined plates 32, which constitute a ramp, are installed at the upper part of the inlet side of the sedimentation tank. By directing the mixed water overflowing from the maturation tank 20 through the ramp, the flow of the mixed water in the sedimentation tank 30 can be made into a uniform downward flow.

[0050] <7> summary According to the configuration of this embodiment, the first circulation pump 40 and the second circulation pump 80 can be operated simultaneously in accordance with the amount of slurry separated from the raw water A to increase the amount of slurry discharged, or the second circulation pump 80 can be used to supply the settled slurry to the first cyclone 50 in the event of a failure of the first circulation pump 40. [Examples]

[0051] The aging tank 20 according to the present invention is not required to be used in combination with other components used in the coagulation and sedimentation apparatus described in Examples 1 to 3 (coagulation tank 10, aging tank 20, sedimentation tank 30, first circulation pump 40, first cyclone 50, second circulation pump 80, second cyclone 90, recovery tank 60, and concentration tank 70). In other words, the maturation tank 20 according to the present invention can be used in combination with any component as a means for forming and maturing bound flocs in influent water containing at least the raw water A, in a sedimentation apparatus for separating slurry from raw water A. [Explanation of symbols]

[0052] A: Raw water B: Treated water C: Sludge D: Inorganic flocculant E: Carbon dioxide F: Polymer flocculant G: Sedimentation accelerator 10:Flocculation tank 11: Line Mixer 20: Aging tank 21: First dividing tank 22: Second division tank 23: Baffle 24: Guidance channel 30: Sedimentation tank 31: Weir board 32: Inclined plate 40: First circulation pump 50: The First Cyclone 60: Recovery tank 70:Concentrator tank 80: Second circulation pump 90: The Second Cyclone

Claims

1. A maturation tank used in a coagulation and sedimentation apparatus that separates raw water into sludge and treated water, The maturation tank has the function of maturing bound flocs formed by the binding of flocs in the influent water with the settling accelerator by adding a polymer flocculant and a settling accelerator to the influent water which contains at least the raw water to which an inorganic flocculant has been added, and stirring the mixture. The aging tank consists of a plurality of divided tanks through which the inflowing water passes sequentially, and each divided tank is equipped with an independently controllable stirring device. The invention is characterized in that a baffle is provided at the outlet of at least one of the plurality of divided tanks for circulating the downward flow produced by the stirring device. A maturation tank for a coagulation and sedimentation apparatus.

2. The plurality of divided tanks, A first dividing tank, which promotes the formation of the bound flocs by adding the polymer flocculant and sedimentation accelerator to the influent water and stirring, A second dividing tank, which promotes the growth of the bound flocs by stirring the overflow water from the first dividing tank with a weaker force than the stirring in the first dividing tank, Characterized by including at least the following: A maturation tank for a flocculation and sedimentation apparatus according to claim 1.

3. The invention is characterized by providing a plurality of the second divided tanks, and allowing the overflow water from the first divided tank to pass through each of the second divided tanks in sequence. A maturation tank for a flocculation and sedimentation apparatus according to claim 2.

4. The invention is characterized in that at least one of the plurality of divided tanks is provided with a window for visually inspecting the inside of the tank. A maturation tank for a flocculation and sedimentation apparatus according to claim 1.

5. A coagulation and sedimentation apparatus that separates raw water into sludge and treated water, It comprises at least a coagulation tank, a maturation tank, a sedimentation tank, a first circulation pump, a first cyclone, a recovery tank, and a concentration tank. The coagulation tank has the function of agitating and mixing the raw water, the overflow water from the concentration tank, and a mixed water containing at least an inorganic coagulant to coagulate suspended solids. The aforementioned maturation tank has the function of maturing bound flocs formed when flocs in the mixed water combine with the settling accelerator by adding a polymer flocculant and a settling accelerator to the mixed water from the coagulation tank and stirring and mixing them. The sedimentation tank has the function of settling bound flocs in the mixed water from the maturation tank and separating the mixed water into the treated water and the sedimented slurry. The first circulation pump has the function of supplying at least the sediment slurry removed from the sedimentation tank to the first cyclone. The first cyclone has the function of separating the sedimentation slurry supplied from the first circulation pump into a separation slurry and a muddy substance containing the sedimentation accelerator, supplying the muddy substance as part or all of the sedimentation accelerator to the maturation tank, and supplying the separation slurry to the recovery tank. The recovery tank has the function of separating the slurry from the first cyclone into a recovered slurry and a muddy substance containing the settling accelerator, supplying the muddy substance as part or all of the settling accelerator to the maturation tank, and supplying the recovered slurry to the concentration tank. The aforementioned thickening tank has the function of allowing the recovered slurry from the recovery tank to remain for a predetermined time to concentrate it before removing it as sludge, and supplying the overflow as overflow water to the coagulation tank. The maturation tank is characterized by comprising a plurality of divided tanks through which the mixed water from the coagulation tank passes sequentially, and each divided tank is equipped with an independently controllable stirring device. Coagulation and sedimentation apparatus.

6. Further comprising a second circulation pump and a second cyclone, The second circulation pump has the function of supplying at least the sediment slurry removed from the sedimentation tank to the first cyclone and / or the second cyclone. The second cyclone has the function of separating the sedimentation slurry supplied from the second circulation pump into a separation slurry and a muddy substance containing the sedimentation accelerator, supplying the muddy substance as part or all of the sedimentation accelerator to the maturation tank, and supplying the separation slurry to the concentration tank. The concentration tank is characterized by having the function of allowing the recovered slurry from the recovery tank and the separated slurry from the second cyclone to remain for a predetermined time to concentrate before removing them as sludge, and supplying the overflow as overflow water to the coagulation tank. The coagulation and sedimentation apparatus according to claim 5.

7. The system is further characterized by comprising a line mixer that pre-mixes an inorganic coagulant with carbon dioxide gas with the raw water sent to the coagulation tank. The coagulation and sedimentation apparatus according to claim 5.

8. The plurality of divided tanks A first dividing tank, which promotes the formation of the bound flocs by adding the polymer flocculant and sedimentation accelerator to the influent water and stirring, A second dividing tank, which promotes the growth of the bound flocs by stirring the overflow water from the first dividing tank with a weaker force than the stirring in the first dividing tank, Characterized by including at least the following: The coagulation and sedimentation apparatus according to claim 5.

9. A plurality of the second divided tanks are provided, and the overflow water from the first divided tank is passed through each of the second divided tanks in order, The coagulation and sedimentation apparatus according to claim 8.

10. At least one of the plurality of divided tanks is provided with a window for viewing the inside of the tank, The coagulation and sedimentation apparatus according to claim 5.

11. A baffle is provided at the outlet of at least one of the plurality of divided tanks for circulating the downward flow produced by the stirring device. The coagulation and sedimentation apparatus according to claim 5.

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