Flocculation floc separator and wastewater treatment device equipped with the same

Abstract

To provide a flocculation flock separation device where waste water difficult to predict whether flocculation flock is precipitated or floated can be treated on site and further the flocculation flock can be efficiently separated by flowing the waste water in a tangential direction and making a swirl flow.SOLUTION: A flocculation flock separation device comprises a separation tank 12 and a separation acceleration cylinder 13 disposed at the center of the separation tank 12 so as to have a center axis 14 in a vertical direction. The separation acceleration cylinder 13 is constituted with a cylindrical part 15 and an inflow part 17 being installed at a center part in a height direction of the cylindrical part 15 and flowing waste water in a tangential direction of a cylindrical part inner periphery. The flocculation flock is aggregated while spirally falling, precipitated and separated in a case that the flocculation flock is heavier than water. The flocculation flock is aggregated while spirally rising, floated and separated in a case that the flocculation flock is lighter than water.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a technology for a flocculation separator capable of performing solid-liquid separation whether flocs settle or float. [Background technology]

[0002] When treating wastewater, a flocculant or flocculating adsorbent is added to the wastewater and stirred to form flocs, after which solid-liquid separation is carried out in a separation tank. In this solid-liquid separation, flocs with a high specific gravity (such as inorganic wastewater from concrete cutting) generally settle, while flocs with a low specific gravity (such as organic domestic wastewater) generally float.

[0003] Therefore, it is necessary to select a wastewater treatment device that is suitable for the wastewater conditions.

[0004] However, in the case of paint peeling wastewater, it is often impossible to predict from the state of the wastewater whether the flocs will settle or float, and when treating on-site, it can be difficult to select an appropriate treatment device.

[0005] On the other hand, as a coagulation settling device for coagulated flocs, a device has been proposed in which wastewater in which coagulated flocs have been formed around the periphery of a cylindrical coagulation settling device is introduced in a tangential direction and made to flow in a swirling flow, thereby efficiently settling and separating the coagulated flocs (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3922921 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the coagulation settling device described in Patent Document 1 is also based on the premise that coagulated flocs will settle, and does not take into account the case where coagulated flocs will float up.

[0008] Therefore, the present invention proposes a flocculation and floc separation device that can treat wastewater on-site, where it is impossible to predict whether flocs will settle or float, and that can efficiently separate flocs by causing wastewater to flow tangentially, thereby generating a swirling flow. [Means for solving the problem]

[0009] The flocculation floc separation apparatus according to the first invention is an flocculation floc separation apparatus for performing solid-liquid separation of wastewater in which flocs have formed, and comprises a separation tank and a separation promotion cylinder arranged in the center of the separation tank so that its central axis is in the vertical direction, and the separation promotion cylinder is composed of a cylindrical portion and an inlet portion installed in the center of the height direction of the cylindrical portion and through which the wastewater flows in a tangential direction of the inner circumference of the cylindrical portion, and when the flocs are heavier than water, the flocs gather and settle while swirling down, and when the flocs are lighter than water, the flocs gather and float up while swirling up, and are separated and a movable partition plate disposed in the separation tank near a discharge port for treated water provided on a side surface of the separation tank, the movable partition plate being displaceable between a communicating position that communicates with an upper region in the separation tank and a blocking position that blocks the upper region, so that when the flocs are heavier than water, the movable partition plate is in the communicating position, and the treated water flowing out of the separation promotion cylinder passes through the upper region and is discharged to the discharge port, and when the flocs are lighter than water, the movable partition plate is in the blocking position, and the discharge of the flocs floating up from the separation promotion cylinder to the discharge port is blocked. It is characterized by:

[0010] In the flocculation and floc separation apparatus according to the first aspect of the present invention, if the flocs are heavier than water, they gather and settle while swirling down, and if the flocs are lighter than water, they gather and float up while swirling up. Therefore, even if it is not possible to predict whether the flocs will settle or float up, the same wastewater treatment apparatus can be used. Furthermore, in the flocculation floc separation apparatus according to the first invention, when the flocs are heavier than water, the treated water can be removed while the flocs are accumulating at the bottom of the separation tank. When the flocs are lighter than water, the treated water can be removed while the flocs are accumulating at the top of the separation tank. Therefore, even when it is not possible to predict whether the flocs will settle or float, the same wastewater treatment apparatus can be used to treat wastewater.

[0011] The floc separator according to a second aspect of the present invention is characterized in that the separation promoting cylinder further has an inner flange portion at the upper end of the cylindrical portion.

[0012] In the flocculation separator according to the second aspect of the present invention, as flocs swirl and rise along the inner periphery of the cylindrical part of the separation promotion tube, the inner flange at the upper end of the cylindrical part generates a swirling flow that concentrates more toward the central axis. Therefore, if the flocs are lighter than water, they will form a columnar shape and swirl and rise, allowing the flocs to gather and float up for more efficient separation. [Effects of the Invention]

[0015] The floc separation device of the present invention can treat wastewater on-site even when it is not possible to predict whether flocs will settle or float.Furthermore, by causing wastewater to flow tangentially and creating a swirling flow, flocs can be efficiently separated. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a wastewater treatment device equipped with a flocculation separation device according to an embodiment of the present invention. [Figure 2] 1 is a plan view of an aggregated floc separation device according to an embodiment of the present invention. [Figure 3] 3 is a cross-sectional view AA of the floc separator shown in FIG. 2. [Figure 4] FIG. 1 is a plan view showing wastewater flowing into a separation promotion cylinder of a floc separator in a tangential direction to the inner circumference of a cylindrical portion. [Figure 5] 5 is a cross-sectional view taken along the arrow BB in FIG. 4, showing the state of the swirling flow of wastewater inside the cylindrical portion when the aggregated flocs are heavier than water. FIG. [Figure 6] 5 is a cross-sectional view taken along the arrow BB in FIG. 4, showing the state of the swirling flow of wastewater inside the cylindrical portion when the aggregated flocs are lighter than water. FIG. [Figure 7] FIG. 1 is a diagram illustrating the operation of the floc separator when flocs are heavier than water. [Figure 8] FIG. 1 is a diagram illustrating the operation of the floc separator when flocs are lighter than water. DETAILED DESCRIPTION OF THE INVENTION

[0017] Fig. 1 is a perspective view of a wastewater treatment device 2 equipped with a flocculation floc separator 1 according to an embodiment of the present invention. 3 denotes a stirring tank in which a flocculant or flocculating adsorbent is added to and stirred in stored wastewater. 4 denotes an inner agitator in which wastewater transferred from the stirring tank 3 is agitated by an internal agitator blade as it passes through the inner agitator.

[0018] The wastewater that has passed through the inner agitator is transferred to the flocculation and floc separation apparatus 1 according to an embodiment of the present invention. Details of the flocculation and floc separation apparatus 1 will be described later.

[0019] Reference numeral 6 denotes a dewatering tank in which wastewater containing a high concentration of flocs separated by the flocculation floc separator 1 is separated into dewatered cake and treated water. Reference numeral 7 denotes a diaphragm pump that transfers wastewater containing a high concentration of flocs from the flocculation floc separator 1 to the dewatering tank 6. The diaphragm pump 7 also transfers treated water from the dewatering tank 6 to a neutralization tank 8. In the neutralization tank 8, the treated water is stored, and then a neutralizing agent is added to produce reclaimed water. Stainless steel, which is resistant to corrosion, is mainly used as the material for each device that makes up the wastewater treatment device 2 described above.

[0020] The wastewater treatment device 2 shown in Fig. 1 is further provided with piping (not shown) that connects the above-mentioned devices, tanks, etc. Reference numeral 10 denotes a step stool with an open top so that an operator can stand on it. An operator standing on the step stool 10 can directly view the wastewater in the above-mentioned stirring tank 3, flocculation floc separator 1, and neutralization tank 8. This allows the operator to accurately observe the status of wastewater treatment by the wastewater treatment device 2.

[0021] Reference numeral 11 denotes a control panel for the wastewater treatment device 2. The wastewater treatment device 2 uses many electric and electronic components such as sensors, actuators, and motors. These electric and electronic components are electrically connected to the control panel 11. The electric and electronic components of the wastewater treatment device 2 are controlled by the control panel 11 so that they operate automatically according to a stored wastewater treatment flow. In addition, by operating the operating section of the control panel 11, an operator can select different wastewater treatment flows depending on the state of the wastewater.

[0022] As shown in Figure 1, the wastewater treatment device 2 is formed as a rectangular parallelepiped with a length L, width W, and height H. All of the devices and equipment that make up the wastewater treatment device 2 are neatly and compactly arranged inside the rectangular parallelepiped. Furthermore, three sides of this rectangular parallelepiped are sized to fit on the bed of a truck. Therefore, the wastewater treatment device 2 is easy to load onto a truck and can be easily transported to a site where wastewater treatment is required.

[0023] Next, a detailed configuration of the floc separating apparatus 1 according to an embodiment of the present invention will be described. Fig. 2 is a plan view of the floc separating apparatus 1. Fig. 3 is a cross-sectional view taken along line AA of the floc separating apparatus 1 shown in Fig. 2. The configuration of the floc separating apparatus 1 will be described below with reference to Figs. 2 and 3.

[0024] The floc separator 1 comprises a separation tank 12 and a separation promotion cylinder 13 disposed in the center of the separation tank 12 with its central axis 14 oriented in the vertical direction.

[0025] The separation promotion tube 13 is composed of a cylindrical section 15 that is open at the bottom, an inner flange section 16 whose tip extends circumferentially from the upper end of the cylindrical section 15 inward, and an inlet section 17 that is installed in the center of the height of the cylindrical section 15 and allows wastewater to flow in a tangential direction to the inner circumference of the cylindrical section.

[0026] As shown in Figures 2 and 3, the separation tank 12 has an approximately rectangular parallelepiped shape overall, with the bottom 18 having a square pyramid shape that is convex downward. The top 19 of the separation tank 12 is open, allowing the interior to be seen. The separation tank 12 is manufactured by bending and welding thin stainless steel plates.

[0027] An inlet pipe 20 connected to the inner agitator is connected to the inlet section 17. A treated water outlet 21 is provided at the top of the other side surface 26 of the separation tank 12 in the height direction. A discharge port 22 for removing settled flocs is provided at the center of the bottom of the separation tank 12.

[0028] As shown in Figures 2 and 3, a movable partition plate 23 is joined to the inner surface of the separation tank 12 and disposed inside the separation tank 12 near the discharge outlet 21 on the other side surface 26 of the separation tank 12. A fixed partition plate 24 is disposed immediately adjacent to the movable partition plate 23. As shown in Figure 2, the left-right length of the fixed partition plate 24 is the same as the left-right inner dimension of the separation tank 12. As shown in Figure 3, a lower end 27 of the fixed partition plate 24 is separated from the bottom 18 of the separation tank 12, providing a space. In addition, an upper end 28 of the fixed partition plate 24 is at approximately the same height as the lower end of the opening cross section of the discharge outlet 21. A flow path 29 for treated water is formed between the fixed partition plate 24 and the other side surface 26 of the separation tank 12.

[0029] As shown in FIG. 2, the length of the movable partition plate 23 in the left-right direction is slightly smaller than the inner dimension of the separation tank 12 in the left-right direction. Furthermore, as shown in FIG. 3, the lower end of the movable partition plate 23 is pivotally attached to the fixed partition plate 24 by a hinge 30 so as to be able to swing freely. In FIG. 3, the blocking position in which the movable partition plate 23 blocks the upper region 31 of the separation tank 12 is shown by a solid line. The upper end of the movable partition plate 23 in the blocking position is slightly higher than the height of the discharge port 21. Furthermore, the communicating position in which the movable partition plate 23 communicates with the upper region 31 of the separation tank 12 is shown by a two-dot chain line. The upper end of the movable partition plate 23 in the communicating position is approximately flush with the upper end 28 of the fixed partition plate 24. Instead of swinging, the movable partition plate 23 may be slidable.

[0030] Although the mechanism for changing the position of the movable partition plate 23 is not particularly shown, various known mechanisms can be employed. For example, a mechanism using a hydraulically driven cylinder or motor, an electrically driven motor, a mechanism using a reducer, etc. can be employed. These mechanisms can be controlled by the control panel 11 shown in FIG. 1. The position of the movable partition plate 23 may also be changed manually.

[0031] The functions and effects of the flocculating floc separating apparatus 1 according to the embodiment of the present invention, the configuration of which has been explained above, and the wastewater treatment apparatus 2 equipped with the flocculating floc separating apparatus 1, are as follows.

[0032] (When the floc is heavier than water) In the wastewater treatment device 2 shown in Fig. 1, a flocculant or flocculating adsorbent is added to and stirred in the stirring tank 3, and then the wastewater is further stirred by being transferred through the inner stirrer 4. As a result, flocs are formed in the wastewater. The wastewater with flocs formed is transferred to the flocculation floc separator 1.

[0033] FIG. 4 is a plan view showing how wastewater flowing through the inlet pipe 20 flows in the tangential direction of the inner circumference of the cylindrical portion 15 of the separation promotion cylinder 13 of the floc separator 1.

[0034] As shown in Fig. 4, wastewater 32 containing flocs 33 (floc particles are represented by +) forms a clockwise swirling flow along the inner circumference of cylindrical portion 15. The direction of the swirling flow is indicated by arrow 34.

[0035] Fig. 5 is a cross-sectional view taken along the arrow BB in Fig. 4, showing the state of the swirling flow of wastewater 32 inside the cylindrical portion 15. As shown in Fig. 5, since the flocs 33 are heavier than water, the wastewater 32 containing the flocs 33 descends in a cylindrical shape while swirling along the inner periphery of the cylindrical portion 15. During this process, the flocs 33 gather and are separated by settling.

[0036] 7 is a diagram illustrating the operation and effect of the floc separator 1 when the flocs 33 are heavier than water. At this time, the movable partition plate 23 is in the communicating position, and the upper region 31 of the separation tank 12 is in a communicating state.

[0037] The flocs 33 settle at the bottom 18 of the separation tank 12. A portion of the treated water 35 (treated water is represented by a circle) remaining after the flocs 33 have been separated from the wastewater 32 flows from the bottom of the separation promotion cylinder 13 toward the bottom 18 of the separation tank 12, then passes through the flow path 29 and is discharged from the discharge port 21. The flow of the treated water is represented by dashed arrows.

[0038] The remainder of the treated water 35 flows through the opening 36 of the inner flange portion 16 of the separation promotion cylinder 13 into the upper region 31 of the separation tank 12. At this time, since the movable partition plate 23 is in the communicating position in the upper region 31, the treated water 35 is discharged from the discharge port 21.

[0039] In this way, if the flocculated flocs 33 are heavier than water, the flocculated flocs 33 are precipitated and flocculated at the bottom 18 of the separation tank 12. The treated water 35 is discharged from the discharge port 21 and transferred to the neutralization tank 8.

[0040] As described above, according to the floc separator 1 of the embodiment, the flocs 33 can be efficiently separated from the wastewater 32 while the wastewater 32 containing the flocs 33 swirls along the inner periphery of the cylindrical portion 15 of the separation promotion cylinder 13. In this way, if the flocs 33 are heavier than water, they can gather into a cylindrical shape while swirling down and be separated by settling.

[0041] The highly concentrated flocculated flocs 33 containing water that have settled at the bottom 18 of the separation tank 12 are transferred from the outlet 22 to the dewatering tank 6 by the diaphragm pump 7 (see Figure 1), and are separated into treated water and dewatered cake in the dewatering tank 6.

[0042] (When the floc is lighter than water) As shown in FIG. 4, the wastewater flowing through the inlet pipe 20 flows in the tangential direction of the inner circumference of the cylindrical portion 15 of the separation promotion cylinder 13 of the floc separation device 1, in the same manner as when the flocs are heavier than water.

[0043] Fig. 6 is a cross-sectional view taken along the arrow BB in Fig. 4, showing the swirling flow of wastewater 32 inside the cylindrical portion 15. As shown in Fig. 6, because the flocculated flocs 33 are lighter than water, the wastewater 32 containing the flocculated flocs 33 rises in a columnar shape while swirling around the center of the cylindrical portion 15. The wastewater 32 containing the flocculated flocs 33 flows upward through an opening 36 on the inside of the inner flange portion 16 of the separation tank 12. The flocculated flocs 33 are separated by floating while gathering together. In this way, the inner flange portion 16 generates a swirling flow that is concentrated closer to the central axis 14.

[0044] 8 is a diagram illustrating the operation and effect of the floc separator 1 when the flocs 33 are lighter than water. At this time, the movable partition plate 23 is in the blocking position, and the upper region 31 of the separation tank 12 is in a blocking state.

[0045] The flocculated flocs 33 float and flocculate in the upper part 19 of the separation tank 12. After the flocculated flocs 33 are separated from the wastewater 32, the entire amount of treated water 35 (treated water is represented by a circle) flows from the lower part of the separation promotion cylinder 13 to the bottom part 18 of the separation tank 12, then passes through the flow path 29 and is discharged from the discharge port 21.

[0046] As described above, if the flocs 33 are lighter than water, they float and flocculate in the upper part 19 of the separation tank 12. The treated water 35 is discharged from the discharge port 21 and transferred to the neutralization tank 8.

[0047] As described above, with the floc separation device 1 according to the embodiment, when the flocs are lighter than water, the flocs 33 gather in a columnar shape while swirling upward along the inner periphery of the cylindrical portion 15 of the separation promotion cylinder 13, and can then be floated and separated. At this time, the inner flange portion 16 generates a swirling flow that is concentrated more toward the central axis 14, so that the flocs 33 can be separated from the wastewater 32 more efficiently.

[0048] The water-containing flocs 33 that have risen to the top 19 of the separation tank 12 are transferred from the float-type suction port 37 to the dewatering tank 6 by the diaphragm pump 7 (see Figure 1). In the dewatering tank 6, the flocs are separated into treated water and dewatered cake.

[0049] As described above, the flocculating floc separating apparatus 1 according to the embodiment of the present invention can flocculate and separate the flocs 33 whether they settle or float. In other words, the wastewater treatment device 2 equipped with the flocculating floc separating apparatus 1 of the present invention can treat the wastewater 32 on-site even when it is not possible to predict whether the flocs 33 will settle or float.

[0050] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Addition, omission, substitution, and other modifications of the configuration are possible without departing from the spirit of the present invention. The present invention is not limited by the above description, but is defined by the appended claims. [Explanation of symbols]

[0051] 1: Flocculation separator 2: Wastewater treatment equipment 12: Separation tank 13: Separation promotion cylinder 14: Central axis 15: Cylindrical part 16: Inner flange 17:Inflow part 23: Movable partition 32: Wastewater 33: Coagulated floc

Claims

1. A flocculation floc separator for performing solid-liquid separation of wastewater in which flocs have been formed, comprising: A separation tank; a separation promoting cylinder disposed in the center of the separation tank with its central axis in the vertical direction; The separation promoting cylinder is composed of a cylindrical portion and an inflow portion that is installed at the center of the cylindrical portion in the height direction and that allows the wastewater to flow in a tangential direction of the inner circumference of the cylindrical portion, If the flocs are heavier than water, they will gather and settle while spinning down, When the flocs are lighter than water, they gather and float up while rotating and rising. a movable partition plate disposed in the separation tank near a discharge outlet for treated water provided on a side surface of the separation tank; the movable partition plate is displaceable between a communicating position in which the upper region of the separation tank is communicated with and a blocking position in which the upper region is blocked, When the flocs are heavier than water, the movable partition plate is in a communicating position, and the treated water flowing out of the separation promoting cylinder passes through the upper region and is discharged to the discharge port, When the flocs are lighter than water, the movable partition plate is in a blocking position, blocking the flocs floating up from the separation promoting cylinder from being discharged to the discharge port.

2. 2. The floc separator according to claim 1, wherein the separation promoting cylinder further has an inner flange portion at the upper end of the cylindrical portion.

3. A wastewater treatment device comprising the flocculation separator according to claim 1 or 2.

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