JP2012192402A - Solid-liquid separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-liquid separator capable of improving the separation efficiency of solids in a reduced space.SOLUTION: The solid-liquid separator includes: a centrifugal separator 3 that swirls raw water containing the solids for centrifugal separation, and has a slurry discharge pipe 5 for discharging slurry containing the solids to the external in a lower part, and has a treated water discharge pipe 7 for discharging treated water to the external in an upper part; a raw water tank 2 for storing the raw water; a water pump P1 that feeds the raw water in the raw water tank to the centrifugal separator by applying pressure; collecting pots 6, 6A, and 6B to which the slurry discharge pipe of the centrifugal separator is inserted, and in which the solids contained in the slurry discharged from the slurry discharge pipe is precipitated in the form of sludge; a supernatant discharge pipe that is inserted in an upper part of the collecting pot, and discharges supernatant water of the slurry in the collecting pot; and a sludge discharge pipe 8 that discharges the sludge precipitated in a lower part of the collecting pot. A gap is provided between a lower end 5e of the slurry discharge pipe and a bottom 6b of the collecting pot, and the lower end 5e of the slurry discharge pipe is positioned lower than a lower end 7e of the supernatant discharge pipe.

Description

  Embodiments described herein relate generally to a solid-liquid separator.

The most widely used technique in solid-liquid separation is gravity sedimentation such as coagulation sedimentation. This technology has advantages such as clear treated water and no power unit. On the other hand, since this technique requires a huge water tank, there is a problem in terms of installation space. For example, in order to obtain a throughput of 500 m ³ / day by coagulation sedimentation, a sedimentation basin having a diameter of about 5 m is required even if ancillary equipment is excluded.

On the other hand, in order to obtain a throughput of 500 m ³ / day by solid-liquid separation using a centrifuge, for example, a cyclone, a cyclone having a diameter of 20 cm can be used except for incidental equipment, and the installation space can be greatly reduced. However, a cyclone with a smaller particle size and smaller specific gravity is more difficult to separate, and the separation efficiency is inferior to that of a sedimentation basin.

  A method of solid-liquid separation using a cyclone will be schematically described. The raw water to be treated is pumped from the raw water tank to the cyclone using a water pump. The cyclone has an inverted cone shape and does not have a drive unit. The pumped raw water becomes a swirling flow in the cyclone. As a result, the solid matter having a large specific gravity receives centrifugal force, gathers in the vicinity of the wall surface, and is discharged from the bottom as slurry. The discharge of the slurry may be performed continuously or intermittently using a timer or the like. Treated water with a small specific gravity gathers in the center and is discharged from the top to the outside of the system.

JP 2009-279495 A JP 2010-94594 A JP 2010-12467 A JP 2009-45562 A JP 2008-114132 A

  It is known that when the slurry is drawn out from the bottom of the cyclone as described above to create a downward flow, particles flowing out to the treated water side are reduced and the separation efficiency is improved. However, if the slurry is always drawn, the slurry concentration is decreased and the amount of the slurry is increased, so that a treatment such as dehydration is required in the subsequent stage.

  The problem to be solved by the present invention is to provide a solid-liquid separation device capable of improving the separation efficiency of solid matter in a space-saving manner.

  The solid-liquid separation device of the embodiment has a slurry discharge pipe in the lower part for rotating and centrifuging raw water containing solids and discharging the slurry containing solids to the outside, and discharging the treated water to the outside. A centrifuge having a water discharge pipe at the top; a raw water tank for storing raw water; a water supply pump for pumping the raw water of the raw water tank to the centrifuge; and a slurry discharge pipe for the centrifuge being inserted, A recovery pot that settles solids contained in the slurry discharged from the slurry discharge pipe in the form of sludge; a supernatant discharge pipe that is inserted into the upper part of the recovery pot and discharges the supernatant water in the recovery pot; and the recovery A sludge discharge pipe for discharging the sludge settled at the bottom of the pot is provided. A gap is provided between the lower end of the slurry discharge pipe and the bottom of the recovery pot, and the lower end of the slurry discharge pipe is at a position lower than the lower end of the supernatant discharge pipe.

The block diagram which shows the solid-liquid separator which concerns on 1st Embodiment. The block diagram which shows the solid-liquid separator which concerns on 2nd Embodiment. The block diagram which shows the solid-liquid separator which concerns on 3rd Embodiment. The block diagram which shows the solid-liquid separator which concerns on 4th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 5th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 6th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 7th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 8th Embodiment. The top view of the collection | recovery pot of FIG. The block diagram which shows the solid-liquid separator which concerns on 9th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 10th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 11th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 12th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 13th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 14th Embodiment. The block diagram which shows the solid-liquid separator which concerns on 15th Embodiment. The top view of the baffle plate provided in the collection | recovery pot of FIG.

  Hereinafter, a solid-liquid separator according to an embodiment will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals and description thereof is omitted.

(First embodiment)
FIG. 1 shows a schematic diagram of a solid-liquid separation apparatus 1 according to the first embodiment.
The raw water tank 2 stores raw water containing solids to be processed. The raw water in the raw water tank 2 is pressurized and fed to a centrifuge, for example, a cyclone 3 by a water pump P1. The cyclone 3 itself does not have a power source such as an electric motor, and is solid-liquid separated by the action of water supply pressure from the pump P1 and gravity. Therefore, the lower part of the cyclone 3 has a tapered inverted truncated cone shape. The raw water pressurized and fed from the water feed pump P1 to the cyclone 3 becomes a swirling flow in the cyclone 3. Centrifugal force is generated by this swirling flow, and the solid and liquid are separated by the specific gravity difference. A substance having a low specific gravity, such as water, flows upward from the central portion of the swirling flow through the upper treated water discharge pipe 4 and is discharged outside as treated water through a drain line L2 connected to the discharge pipe 4. A substance having a high specific gravity, for example, a solid substance such as metal particles, receives centrifugal force and is pressed against the inner wall of the cyclone 3 to descend along the inclined wall surface. The slurry containing the solid substance passes through the slurry discharge pipe 5 at the lower end. The cyclone 3 is discharged.

  A semi-sealed recovery pot 6 is provided below the cyclone 3. The slurry discharge pipe 5 passes through the top plate of the recovery pot 6, and the lower end portion 5 e is inserted into the recovery pot 6. In the recovery pot 6, solid matter is settled and separated from the slurry by gravity settling. One end of a supernatant discharge pipe 7 is inserted into the top plate of the recovery pot 6 so that the supernatant water of the slurry recovered in the recovery pot 6 is discharged to the outside. A sludge discharge line L3 is provided at the lower part of the recovery pot 6, and solids settled and concentrated from the slurry recovered in the recovery pot 6 accumulate as sludge, and the accumulated sludge is periodically or as required. It is discharged from the collection pot 6 at any time. The sludge discharge line L3 is provided with a sludge discharge valve V1. Sludge is discharged from the collection pot 6 to the sludge discharge line L3 continuously or intermittently.

  In the solid-liquid separation device of the present embodiment, it is preferable that each member is configured as follows in order to improve the efficiency of sedimentation / separation of solids in the recovery pot 6.

  The volume of the collection pot 6 is preferably larger than the volume of the cyclone 3. If this condition is satisfied, the flow rate of the slurry in the collection pot 6 can be reduced, which is advantageous for the sedimentation and separation of solid matter by gravity sedimentation. The lower end 7e of the supernatant discharge pipe does not necessarily need to be below the top plate of the collection pot 6, and may be equal to the position level of the top plate.

  When the lower end portion 5e of the slurry discharge pipe reaches the interface of the sludge accumulated on the bottom portion 6b of the recovery pot, the slurry flow discharged from the slurry discharge pipe agitates the sludge accumulation layer and floats a part of the deposited solid matter. An upward flow is formed. The suspended solid may rise in the recovery pot 6, reach the lower end 7 e of the supernatant discharge pipe, and flow out with the supernatant water through the supernatant discharge pipe 7. Such a solid outflow increases the turbidity of the supernatant water and is unfavorable for the sedimentation and separation of the solid.

  Therefore, in the present embodiment, the lower end portion 5e of the slurry discharge pipe is disposed at a position that is higher than the bottom portion 6b of the recovery pot by the gap G1, so that the lower end portion 5e of the slurry discharge pipe is not in direct contact with the interface of the sludge deposit layer. Yes. Specifically, the lower end portion 5e of the slurry discharge pipe is positioned in the collection pot 6 so that the height difference h1 of the gap G1 is in the range of 2/3 to 1/4 of the depth d of the collection pot 6. Further, in order to avoid the lower end portion 5e of the slurry discharge pipe from reaching the interface of the sludge accumulation layer, an appropriate amount of sludge is periodically discharged from the recovery pot 6 through the sludge discharge line L3 or necessary. Accordingly, it is preferable to discharge at any time.

  Furthermore, it is preferable to arrange | position the lower end part 5e of a slurry discharge pipe in the place lower than the lower end part 7e of a supernatant discharge pipe. The larger the height difference h2 from the lower end portion 5e of the slurry discharge pipe to the lower end portion 7e of the supernatant discharge pipe, the more the solids are prevented from flowing into the supernatant water discharge line L4, and the solids are separated by gravity sedimentation. To be advantageous.

  The diameter (cross-sectional area) of the slurry discharge pipe 5 and the diameter (cross-sectional area) of the supernatant discharge pipe 7 are determined based on the sedimentation speed of the solid matter in the slurry discharged from the slurry discharge pipe 5 and the supernatant discharge pipe 7. It can be determined from the flow rate of the supernatant water. That is, the pipe diameter d1 (cross-sectional area A1) of the slurry discharge pipe 5 and the pipe diameter d2 (cross-sectional area A2) of the supernatant discharge pipe 7 can be determined so as to satisfy the condition of the following inequality (1).

vs> vw (1)
However, the symbol vs indicates the sedimentation rate of the solid matter in the slurry discharged from the slurry discharge pipe, and the symbol vw indicates the flow rate of the supernatant water discharged from the supernatant discharge pipe.

  The solid sedimentation velocity vs can be calculated using the Stokes sedimentation equation. Moreover, the flow velocity vw of the supernatant water can be calculated using the continuous equation (2).

vw = Q / A2 (2)
However, the symbol Q indicates the difference obtained by subtracting the sludge discharge amount from the slurry discharge amount, and the symbol A2 indicates the cross-sectional area of the inner portion of the supernatant discharge pipe.

  In addition, a valve is attached to each of the slurry discharge pipe 5 and the supernatant discharge pipe 7 so as to adjust the relationship between the diameter (cross-sectional area) of each discharge pipe and the discharge amount of the slurry, sludge and supernatant water. Good.

  According to this embodiment, the slurry discharged from the cyclone 3 is re-concentrated in the collection pot 6, so that a high-concentration sludge can be obtained and at the same time the supernatant water from the supernatant discharge pipe 7 can be clarified. At this time, since the operation can be performed without limiting the discharge amount of the slurry, it is advantageous for clarifying the treated water by the cyclone 3. Moreover, since the moisture content of sludge falls, processing facilities, such as a dehydrator provided in the back | latter stage of the collection pot 6, can be made unnecessary, or it can be made simple. Further, by using the clarified supernatant water as water for use, it is possible to effectively use water in the plant.

  In the present embodiment, a semi-sealing type recovery pot 6 is used, but not limited to this, an open type without a top plate is used to obtain supernatant water overflowing from the supernatant discharge pipe 7. It may be. In addition, if the moisture content of the sludge discharged from the sludge discharge line L3 is too low (sludge fluidity is too low) and natural flow is difficult, a pressure pump may be provided to pump the sludge. Good.

  In the present embodiment, the cyclone is used as the centrifuge, but the present invention is not limited to this, and a centrifuge such as a decanter or a centrifugal sedimentator can be used.

  Furthermore, in this embodiment, since the substances are separated using the specific gravity difference between the substances in the mixture, oils and fats having a specific gravity of less than 1 can be separated and recovered.

(Second Embodiment)
A solid-liquid separator according to the second embodiment will be described with reference to FIG.

  The difference between the solid-liquid separation device 1A of this embodiment and the device 1 of the first embodiment is that a partition plate 9 is provided between the slurry discharge pipe 5 and the supernatant discharge pipe 7 in the recovery pot 6. . The partition plate 9 shown in FIG. 2 has the same width as the width of the collection pot 6 (inner dimension in the depth direction in FIG. 2), and a gap is provided between the lower end of the partition plate 9 and the bottom of the collection pot 6. ing.

  In the solid-liquid separation device according to the second embodiment, by separating the collection pot 6 by the partition plate 9, the solids are settled and separated from the slurry mainly in the section on the slurry discharge pipe 5 side, and the supernatant discharge pipe 7 side is separated. The solids contained in the supernatant water in the compartment can be reduced. Here, when the flow of the liquid is somewhat disturbed in the collection pot 6 not provided with the partition plate 9, the solid matter having a small specific gravity may rise with the upward flow and flow out of the supernatant discharge pipe 7. If the partition plate 9 is provided in the collection pot 6 as in the second embodiment, the liquid flow is unlikely to be disturbed in the compartment on the supernatant discharge pipe 7 side, so that the supernatant water can be prevented from being contaminated.

  In the second embodiment, the height difference h3 of the gap G2 between the lower end of the partition plate 9 and the bottom of the collection pot 6 does not reach the interface of sludge accumulated at the bottom of the collection pot 6 at the lower end of the partition plate 9. It is preferable to do so. Therefore, although depending on the volume and shape of the recovery pot 6, the height difference h3 of the gap G2 is set to an appropriate height longer than the lower end of the supernatant discharge pipe 7, for example, from 2 cm. On the other hand, in the second embodiment, there is no restriction that the lower end of the slurry discharge pipe 5 is arranged in the range of 2/3 to 1/2 of the depth of the recovery pot 6 as in the first embodiment. The length of the slurry discharge pipe 5 may be shorter than that in the first embodiment. Although FIG. 2 shows the case where the partition plate 9 extends along the vertical axis, the partition plate 9 may be inclined with respect to the vertical axis.

(Third embodiment)
With reference to FIG. 3, the solid-liquid separator of 3rd Embodiment is demonstrated.

  The difference between the solid-liquid separator 1B of the present embodiment and the apparatus 1 of the first embodiment is that the supernatant discharge line L4 of the recovery pot 6 is connected to the treated water discharge pipe 4 of the cyclone 3. Since the pressure of the treated water discharged from the treated water discharge pipe 4 is higher than the pressure of the supernatant water discharged from the supernatant discharge pipe 7, a water pump is installed in the supernatant discharge pipe 7 if necessary. Also good.

  In the solid-liquid separation device 1B according to the third embodiment, clarified supernatant water can be continuously used as treated water. For this reason, when the treated water is repeatedly used as irrigation water in the production line, the water can be effectively used.

(Fourth embodiment)
With reference to FIG. 4, the solid-liquid separator of 4th Embodiment is demonstrated.

  The difference between the solid-liquid separation device 1C of the present embodiment and the device 1B of the third embodiment is that a switching valve V2 and a sensor S1 are attached to the supernatant discharge line L4 connected to the treated water discharge pipe 4, and the switching valve V2 Is connected to the upstream line L1 of the water pump P1. The sensor S <b> 1 has a function of detecting the quality of the supernatant water discharged from the supernatant discharge pipe 7. As the sensor S1, for example, a turbidimeter, a particle counter, or an optical sensor can be used. When it is detected by the sensor S1 that the clarity of the supernatant water is low (the solid content is high and the water quality is deteriorated), the switching valve V2 is switched based on the detection signal of the sensor S1, and the supernatant water is branched. Water is sent to the pipe upstream of the water pump P1 through the pipe 13, and the treatment by the cyclone 3 is performed again. For example, an electromagnetic valve that opens and closes based on a detection signal from the sensor S1 is used as the switching valve V2.

  For example, when the concentration of the solid matter in the raw water is high, the sludge interface in the recovery pot 6 is likely to rise, so that the solid matter is mixed into the supernatant water, resulting in poor clarity and poor water quality. In the solid-liquid separation device 1C according to the fourth embodiment, when the clarity of the supernatant water is lowered and the water quality is deteriorated, the clarity of the supernatant water is ensured by treating the supernatant water again with the cyclone 3. be able to.

  In addition, you may provide sensor S1 in the treated water discharge pipe 4 downstream from the connection point of the supernatant discharge line L4.

  In addition, when the recovery of the solid matter has priority over the improvement of the quality of the treated water, the sludge discharge amount is adjusted by controlling the opening degree of the sludge discharge valve V1 based on the detection signal from the sensor S1. May be.

(Fifth embodiment)
A solid-liquid separator according to a fifth embodiment will be described with reference to FIG.

  The solid-liquid separation device 1D of the present embodiment is different from the device 1 of the first embodiment as follows. In the downstream line L4 of the supernatant discharge pipe 7, a drug injection device 14, a stirring device 15, and a second cyclone 16 are sequentially provided. In the second cyclone 16, the treated water is drained from the second cyclone 16 via the second treated water discharge pipe 17 provided in the upper part thereof, and the second slurry discharge pipe 18 provided in the lower part thereof. The slurry is discharged from the inside of the second cyclone 16 via the.

  A second recovery pot 19 is provided below the second cyclone 16. The second slurry discharge pipe 18 and the second supernatant discharge pipe 20 pass through the top plate of the second recovery pot 19 respectively, and their lower end portions 18e and 20e are inserted into the second recovery pot 19, respectively. Yes. In this case, the lower end 18e of the second slurry discharge pipe is disposed at a height difference h4 from the bottom 19b of the second recovery pot, and the lower end 18e of the slurry discharge pipe is in direct contact with the interface of the sludge deposit layer. I try not to. Specifically, the lower end portion 18e of the second slurry discharge pipe is placed in the second recovery pot so that the height difference h4 is in the range of 2/3 to 1/4 of the depth d of the second recovery pot 19. 19 is located. Further, in order to avoid the lower end portion 18e of the second slurry discharge pipe from reaching the interface of the sludge accumulation layer, an appropriate amount of sludge is periodically discharged from the second recovery pot 19 through the sludge discharge line L7. Or drain as needed.

  Furthermore, the lower end portion 18e of the second slurry discharge pipe is disposed at a position lower than the lower end portion 20e of the second supernatant discharge pipe. As the height difference h5 from the lower end 18e of the slurry discharge pipe to the lower end 20e of the supernatant discharge pipe is increased, the outflow of solids to the supernatant water discharge line L8 is suppressed, and the solids are separated by gravity sedimentation. To be advantageous.

  The line L8 of the second supernatant discharge pipe 20 is connected to the line L6 of the second treated water discharge pipe 17, and the second treated water discharge line L6 is further connected to the line L2 of the first treated water discharge pipe 4. ing. A sludge discharge line L7 communicates with the lower portion of the second recovery pot 19 so that the solid matter settled and concentrated from the slurry recovered in the second recovery pot 19 is discharged as sludge. The sludge discharge line L7 is provided with a second sludge discharge valve V3.

  In the apparatus 1D of the present embodiment, assuming that the supernatant water discharged from the supernatant discharge pipe 7 of the recovery pot 6 does not reach the target water quality, the supernatant water is further supplied to the second cyclone 16 and the second cyclone 16. Process with collection pot 19. That is, after adding the flocculant from the medicine injection device 14 to the supernatant water discharged from the supernatant discharge pipe 7 of the first recovery pot 6, the solids contained in the supernatant water are aggregated by stirring with the stirring device 15. Let Further, the supernatant water containing the agglomerated solid is sent to the second cyclone 16 to perform solid-liquid separation.

  When the supernatant water discharged from the first recovery pot 6 has a flow rate of about 1 to 10 m / s, it is not necessary to provide a water supply pump for pumping the supernatant water to the second cyclone 16, but the flow rate of the supernatant water When the amount of water is insufficient, the supernatant water is pumped to the second cyclone 16 by a water pump. The installation position of the water pump is preferably upstream of the stirring device 15.

  As the flocculant, an inorganic flocculant such as PAC, sulfuric acid band and ferric chloride, an organic polymer flocculant, and the like are selected and used according to the quality of the supernatant water. Since the pH at which aggregation occurs appropriately varies depending on the coagulant used, a pH sensor and a pH adjusting device for adding acid or alkali may be provided upstream or downstream of the drug addition device 14.

  As the stirring device 15, for example, a device that is continuously attached to a flow path of a pipe such as a static mixer is preferable.

  The second cyclone 16 may be small because the amount of treated water is smaller than that of the first cyclone 3. In general, it is known that the smaller the cyclone, the better the separation efficiency. For this reason, depending on the quality of the supernatant water discharged from the first recovery pot 6 and the separation performance of the second cyclone 16, the chemical addition device 14 and the stirring device 15 are not necessarily provided.

  Although not shown in the apparatus 1D in FIG. 5, a water supply pump is provided by providing a valve and a sensor in the line L8 of the second supernatant discharge pipe 20 and branching from the valve, similarly to the apparatus 1C in FIG. A branch pipe connected upstream of the two may be provided.

  Further, when the target water quality cannot be obtained even when the second cyclone 16 is used, a third cyclone may be further provided downstream of the second cyclone. Furthermore, it is possible to install a multi-stage cyclone group in cascade, such that a fourth cyclone is provided downstream of the third cyclone and a fifth cyclone is further provided downstream thereof.

  As a modification, a small sedimentation basin may be installed instead of a downstream cyclone such as the second cyclone.

(Sixth embodiment)
A solid-liquid separator according to a sixth embodiment will be described with reference to FIG.

  The solid-liquid separation device 1E of the present embodiment is different from the device 1 of the first embodiment in that a small-volume collection pot 23 having a smaller volume than the collection pot 6 is installed downstream of the collection pot 6, and the collection pot 6 This is that the supernatant discharge pipe 7 is connected to the small volume recovery pot 23. In this embodiment, the lower end portion 7f of the supernatant discharge pipe is disposed at a height difference h6 from the bottom portion 23b of the small volume recovery pot so that the lower end portion 7f of the supernatant discharge pipe does not directly contact the interface of the sludge deposit layer. ing. Specifically, the lower end portion 7f of the supernatant discharge pipe is positioned in the small volume collection pot 23 so that the height difference h6 is in the range of 2/3 to 1/4 of the depth d of the small volume collection pot 23. .

  A second supernatant discharge pipe 24 is provided above the small volume recovery pot 23. Here, the lower end portion 24e of the second supernatant discharge pipe is disposed higher than the lower end portion 7f of the first supernatant discharge pipe. As the height difference h7 from the lower end portion 7f of the first supernatant discharge pipe to the lower end portion 24e of the second supernatant discharge pipe is increased, the outflow of solid matter to the supernatant water discharge line L4 is suppressed, and gravity settling is performed. It is because it becomes advantageous for the sedimentation separation of the solid substance by this.

  A sludge discharge line L9 is connected to the bottom of the small volume recovery pot 23, and a sludge discharge valve V4 is provided in the sludge discharge line L9. Small volume recovery via the sludge discharge line L9 by opening the sludge discharge valve V4 periodically or as needed to avoid the lower end 7f of the supernatant discharge pipe reaching the interface of the sludge accumulation layer. Sludge can be discharged from the pot 23.

  In the sixth embodiment, a small volume recovery pot 23 is connected in series downstream of the recovery pot 6, and the rise caused by sedimentation of solids and discharge of supernatant water in both the recovery pot 6 and the small volume recovery pot 23. The balance with the flow is kept constant. When the sludge is discharged from the sludge discharge pipe 25 of the small volume recovery pot 23, the flow rate Q = (slurry discharge amount−sludge discharge amount) decreases, and the flow rate of the supernatant water discharged from the small volume recovery pot 23 decreases. Thus, in both the recovery pot 6 and the small-volume recovery pot 23, the balance between solid sedimentation and the upward flow caused by the discharge of the supernatant water is kept constant, so that the mixing of the solids into the supernatant water and the sludge concentration A decrease can be prevented.

  One or more smaller capacity recovery pots may be connected downstream of the small capacity recovery pot 23.

(Seventh embodiment)
With reference to FIG. 7, the solid-liquid separator of 7th Embodiment is demonstrated.

  The difference between the solid-liquid separation device 1F of the present embodiment and the device 1 of the first embodiment is that a large-capacity recovery pot 27 having a larger volume than the recovery pot 6 is installed downstream of the recovery pot 6, and the recovery pot 6 This is because the supernatant discharge pipe 7 is connected to the large volume recovery pot 27. In the present embodiment, the lower end portion 7f of the supernatant discharge pipe is disposed at a height difference h8 from the bottom portion 27b of the large volume recovery pot so that the lower end portion 7f of the supernatant discharge pipe does not directly contact the interface of the sludge deposit layer. ing. Specifically, the lower end portion 7f of the supernatant discharge pipe is positioned in the large-volume collection pot 27 so that the height difference h8 is in the range of 2/3 to 1/4 of the depth d of the large-volume collection pot 27. .

  A second supernatant discharge pipe 28 is provided in the upper part of the large volume recovery pot 27. Here, the lower end portion 28e of the second supernatant discharge pipe is disposed higher than the lower end portion 7f of the first supernatant discharge pipe. As the height difference h9 from the lower end portion 7f of the first supernatant discharge pipe to the lower end portion 28e of the second supernatant discharge pipe is increased, the outflow of solids to the supernatant water discharge line L4 is suppressed, and gravity settling is performed. It is because it becomes advantageous for the sedimentation separation of the solid substance by.

  Further, a sludge discharge pipe 29 is connected to the bottom of the large volume recovery pot 27, and the sludge discharge pipe 29 is provided with a sludge discharge valve V5. Large volume recovery via the sludge discharge line L10 by opening the sludge discharge valve V5 periodically or as needed to avoid the lower end 7f of the supernatant discharge pipe reaching the interface of the sludge accumulation layer. Sludge can be discharged from the pot 27.

  In the seventh embodiment, by connecting a large volume recovery pot 27 in series downstream of the recovery pot 6, the residence time of the supernatant water is lengthened and the solid matter having a lower specific gravity is settled to improve the separation efficiency. Can be made.

  When the desired supernatant water quality cannot be obtained, one or more other large-capacity recovery pots may be connected downstream of the large-capacity recovery pot 27.

(Eighth embodiment)
With reference to FIG. 8 and FIG. 9, the solid-liquid separator of 8th Embodiment is demonstrated.

  The solid-liquid separation device 1G of the present embodiment is different from the device 1 of the first embodiment in that a plurality of cyclones 3 are connected in parallel to a single water pump P1, and each of the plurality of cyclones 3 That is, a plurality of slurry discharge pipes 5 provided in is inserted into a single common recovery pot 6.

  As shown in FIG. 9, the slurry discharge pipes 5 are inserted from the eight cyclones 3 into the common collection pot 6, and a cylindrical partition member 31 is provided between the eight slurry discharge pipes 5 and the supernatant discharge pipe 7g. It is partitioned. A gap with a height difference h10 is formed between the lower end 31e of the partition member and the bottom 6b of the collection pot.

  In the present embodiment, when the slurry is introduced into the inner space of the cylindrical partition member 31 from each slurry discharge pipe 5, the solid matter having a specific gravity greater than that of water settles and accumulates on the bottom 6b of the recovery pot, Those having the same or smaller specific gravity pass through the gap below the partition member 31 into the outer space, and are discharged from the common recovery pot 6 as supernatant water through the supernatant discharge pipe 7g.

  Note that a through-hole 32 such as a slit may be provided in the cylindrical partition member 31 so as not to disturb the fluid flow in the shared collection pot 6.

(Ninth embodiment)
With reference to FIG. 10, the solid-liquid separator of 9th Embodiment is demonstrated.

  The difference between the solid-liquid separation device 1H of the present embodiment and the device 1 of the first embodiment is that a slurry pot 10 is attached to the upper part of the slurry discharge pipe 5. The slurry pot 10 is attached to a non-insertion portion where the slurry discharge pipe 5 is not inserted into the collection pot 6. Preferably, the slurry pot 10 is preferably attached at a position close to the connection portion between the cyclone 3 and the slurry discharge pipe 5, that is, at a position close to the slurry outlet at the bottom of the cyclone.

  The slurry pot 10 is continuously formed on a large-diameter upper portion 10a having an inner diameter larger than the inner diameter of the slurry discharge tube 5 and a lower portion of the large-diameter upper portion 10a. And a reduced diameter lower portion 10c that gradually decreases to the inner diameter. A discharge port 10f is opened at the lowermost portion of the reduced diameter lower portion 10c.

  A semi-sealed recovery pot 6 is provided below the slurry pot 10. The slurry discharge pipe 5 passes through the top plate of the recovery pot 6, and the lower end portion 5 e is inserted into the recovery pot 6. In the recovery pot 6, solid matter is settled and separated from the slurry by gravity settling. One end of a supernatant discharge pipe 7 is inserted into the top plate of the recovery pot 6 so that the supernatant water of the slurry recovered in the recovery pot 6 is discharged to the outside. The insertion length of the slurry discharge pipe 5 with respect to the recovery pot 6 is longer than the insertion length of the supernatant discharge pipe 7. That is, in the collection pot 6, the lower end portion 5e of the slurry discharge pipe is disposed at a position lower than the lower end portion 7e of the supernatant discharge pipe.

  A sludge discharge line L3 is connected to the lower portion of the recovery pot 6 so that the sludge accumulated in the recovery pot 6 is discharged from the recovery pot 6 periodically or as needed. The sludge discharge line L3 is provided with a sludge discharge valve V1. Sludge is discharged from the collection pot 6 to the sludge discharge line L3 continuously or intermittently.

  In the present embodiment, a semi-sealed container is cited as an example of the recovery pot 6, but the present invention is not limited to this. The top plate is eliminated, and supernatant water overflowing from the supernatant discharge pipe 7 is obtained. You may do it. Further, when a large amount of slurry is accumulated in the recovery pot 6, the slurry pot 10 and a valve or the like may be used for separation, and the flange joint may be removed to recover the entire slurry pot 10.

  In this embodiment, a cyclone is used as a centrifuge, but the present invention is not limited to this, and a centrifuge such as a decanter that is a solid-liquid separator, or a centrifugal sedimentator can be used.

  The inner diameter of the slurry discharge pipe 5 and the inner diameter of the supernatant discharge pipe 7 can be determined from the sedimentation rate of particles (suspended substances) contained in the slurry discharged from the slurry discharge pipe 5. That is, by obtaining the cross-sectional areas of the slurry discharge pipe 5 and the supernatant discharge pipe 7 that satisfy both the above expressions (1) and (2), the inner diameter of the slurry discharge pipe 5 and the inner diameter of the supernatant discharge pipe 7 are respectively determined. Determined. Further, valves may be attached to these pipes 5 and 7 so that the inner diameters thereof are adjusted in accordance with the particle and slurry discharge flow rate.

  The operation of the apparatus according to this embodiment will be described.

  The raw water pressurized and fed from the water feed pump P1 to the cyclone 3 becomes a swirling flow in the cyclone 3. Centrifugal force is generated by this swirling flow, and the solid and liquid are separated by the specific gravity difference. A substance having a low specific gravity, such as water, flows upward from the central portion of the swirling flow through the upper treated water discharge pipe 4 and is discharged outside as treated water through a drain line L2 connected to the discharge pipe 4. A substance having a large specific gravity, for example, a solid substance such as metal particles, receives centrifugal force, is pressed against the inner wall of the cyclone 3, descends while swirling along the inclined wall surface, and flows into the slurry discharge pipe 5. The flow rate of the slurry becomes maximum when it flows into the slurry discharge pipe 5. When such a rapid flow passes through the slurry discharge pipe 5 and flows into the recovery pot 6 as it is, the sludge accumulation layer 11 is collapsed, the sludge that is an aggregate of the solid matter is soared, and the solid matter is dispersed in a dispersed state. The dispersed solid matter may reach the opening of the lower end portion 7e of the supernatant discharge pipe, and the solid matter may flow out together with the supernatant water.

  However, in this embodiment, since the slurry pot 10 is provided in the slurry discharge pipe 5, when the rapid slurry swirl flow enters the wide internal space of the slurry pot 10, the slurry pot 10 is greatly decelerated. Thus, after the swirl flow generated in the cyclone 3 is decelerated by the slurry pot 10, the slurry flows into the recovery pot 6, so that the flow is gentle in the recovery pot 6 and the metal particles contained in the slurry by gravity. Etc. settles gently. Then, the sludge accumulated in the recovery pot 6 is discharged to the outside continuously or intermittently through the bottom sludge discharge pipe 8.

  According to the apparatus 1H of the present embodiment, the slurry pot 10 having an inner diameter larger than the inner diameter of the slurry discharge pipe 5 connected to the cyclone 3 is provided, the flow rate of the slurry flowing down the slurry discharge pipe 5 is reduced, and the supernatant is discharged. The outflow of solid matter from the pipe 7 is prevented, and the clarity of the treated water is maintained. In the recovery pot 6 following the slurry pot 10, the internal flow rate is further reduced to separate the particles by gravity sedimentation. The clarified supernatant water is drained from the recovery pot 6 through the supernatant discharge pipe 7. In order to promote sedimentation and separation of particles contained in the slurry, the discharge port of the slurry discharge pipe 5 is installed in the lower part of the recovery pot 6, and the water intake port of the supernatant discharge pipe 7 is installed in the upper part of the recovery pot 6. Sludge is discharged from the sludge discharge pipe 8 at such a frequency that the surface on which the sludge is deposited does not hit the water intake of the supernatant discharge pipe 7. By reconcentrating the slurry discharged from the cyclone 3 in the recovery pot 6, a high-concentration sludge can be obtained, and at the same time, the supernatant water can be clarified. Therefore, the operation can be performed without limiting the amount of the slurry drawn, and the treated water of the cyclone 3 can be clarified.

  Moreover, in the apparatus 1H of this embodiment, since the moisture content of sludge falls, processing facilities, such as a dehydrator used for a back | latter stage, become unnecessary or simple. By clarifying the supernatant water and using it as service water, the water can be effectively used in the plant.

(Tenth embodiment)
With reference to FIG. 11, the solid-liquid separator of 10th Embodiment is demonstrated.

  The solid-liquid separator 1I of the present embodiment is different from the apparatus of the ninth embodiment in that the sludge discharge valve V1 and the sludge discharge pump P2 are provided in the line L3 of the sludge discharge pipe 8, and the treated water discharge pipe 4 A turbidity sensor S2 for measuring the turbidity of treated water is provided in the line L2, and a controller for controlling the opening / closing operation of the sludge discharge valve V1 and the driving of the sludge discharge pump P2 based on the turbidity measured by the sensor S2. 12 is provided.

  The controller 12 calculates the sludge discharge amount based on the input unit to which the measurement signal is input from the turbidity sensor S2, the memory unit for recording and storing the process data so that it can be read as needed, and the input signal and the process data. And a calculation unit for obtaining a drive control amount of the pump P2 and an operation control amount of the valve V1 based on the obtained sludge discharge amount, and a control signal for each of the pump P2 and the valve V1 according to the obtained control amount. And an output unit for outputting.

  As the amount of sludge accumulated in the recovery pot 6 increases with the lapse of operating time and the sludge interface rises, the sludge is trapped in the upward flow from the slurry discharge pipe 5 and the solid matter flows out from the line L2 of the treated water discharge pipe 4. There is a risk of it. In order to prevent such deterioration of the treated water quality, the controller 12 adjusts the operation timing of the pump P2 using a timer when the measurement signal is input from the turbidity sensor S2, and opens the sludge discharge valve V1. And the driving amount of the sludge discharge pump P2 is controlled, and the accumulated sludge is pulled out from the collection pot 6. The turbidity sensor S2 may be directly attached to the pipe 4, or may be opened by branching off the pipe 4, and may be installed at a normal pressure or in a water tank for storing treated water, and measures colored components. You may use particle measuring machines, such as a chromaticity meter and a particle counter.

  The sludge extraction may be intermittent if priority is given to the moisture content of the sludge, and if priority is given to the clarification of the treated water, it is desirable to continuously extract the sludge in order to avoid sludge rising due to turbulence of the flow. .

(Eleventh embodiment)
The solid-liquid separator of the eleventh embodiment will be described with reference to FIG.

  The difference between the solid-liquid separation device 1J of the present embodiment and the device of the ninth embodiment is that the shape of the lower portion of the recovery pot 6A is reduced, and the sludge discharge pump P2 is connected directly below the recovery pot 6A. It is that.

  The recovery pot 6A is continuously formed on a large-diameter upper portion 6a having an inner diameter sufficiently larger than the inner diameter of the slurry pot 10 and a lower portion of the large-diameter upper portion 6a. And a reduced diameter lower portion 6c that gradually decreases to the inner diameter. A discharge port 6f is opened at the lowermost portion of the reduced diameter lower portion 6c.

  In the present embodiment, the sludge discharge pump P2 is installed immediately below the recovery pot 6A, so that the slurry discharged from the cyclone 3 can be recovered without being left behind.

  Further, according to the present embodiment, the sludge (solid agglomerates) can be prevented from rising when the sludge discharge pump P2 is started, and the clarification of the supernatant water and the treated water can be prevented. Can be maintained.

(Twelfth embodiment)
A solid-liquid separator according to a twelfth embodiment will be described with reference to FIG.

  The difference between the solid-liquid separation device 1K of the present embodiment and the device of the ninth embodiment is that a dehydrator 40 is provided at the subsequent stage of the sludge discharge pump P2.

  The slurry that has settled and deposited in the collection pot 6 contains a large amount of moisture. Therefore, by providing a dehydrator 40 in the sludge discharge line L3 and performing direct dehydration, the moisture content of the slurry can be reduced and reduced. The drug injection device 41 is a mechanism for adding a drug such as a polymer flocculant in order to dehydrate sludge in the dehydrator 40.

  The slurry withdrawn from the cyclone 3 by the slurry discharge pipe 5 generally contains a lot of moisture. However, in the apparatus 1K of this embodiment, since the solid matter is settled and separated in the collection pot 6A immediately before the dehydrator 40, the moisture content of the sludge passing through the sludge discharge pump P2 is reduced, and the dehydrator 40 Processing load can be reduced. At the same time, the amount of drug added by the drug injection device 41 can be reduced.

(13th Embodiment)
A solid-liquid separator according to a thirteenth embodiment will be described with reference to FIG.

  The difference between the solid-liquid separation device 1L of the present embodiment and the device of the ninth embodiment is that the aggregation unit 13 is provided in front of the cyclone 3. Although the flocculation unit 13 is illustrated in a simplified manner, an inorganic flocculating agent, an organic polymer flocculating agent, or the like is added to the raw water to be treated to give stirring strength with a static mixer, a stirrer, or the like. It is used for wastewater that has a mechanism for aggregating turbid substances and cannot be treated without using a chemical such as a low specific gravity particle that cannot be separated by the cyclone 3 alone or a flocculant such as a fine particle having a small diameter.

  According to the apparatus 1L of the present embodiment, since the sludge is an aggregate, the additional amount of the drug for dehydration in the drug injection device 41 shown in the above-described apparatus 1K (FIG. 13) is reduced or unnecessary. There is an advantage that it can be directly dehydrated by the dehydrator 40.

(Fourteenth embodiment)
A solid-liquid separator according to a fourteenth embodiment will be described with reference to FIG.

  The difference between the solid-liquid separation device 1M of the present embodiment and the device 1L of the thirteenth embodiment is that an aggregate return line L12 is provided between the dehydrator 40 and the raw water tank 2.

  According to the apparatus 1M of the present embodiment, the aggregate accumulated in the recovery pot 6A holds the coagulant around it, and returns the aggregate to the raw water tank 2 to aggregate the suspended matter in the aggregation unit 13. Property can be improved, and the amount of flocculant added can be greatly suppressed. Furthermore, the amount of drug added from the drug addition device (not shown) at the front stage of the dehydrator 40 can also be suppressed.

(Fifteenth embodiment)
A solid-liquid separator according to a fifteenth embodiment will be described with reference to FIGS. 16 and 17.

  The difference between the solid-liquid separation device 1N of the present embodiment and the device 1K of the thirteenth embodiment is that the collection pot 6B incorporates a baffle plate 61. By separating the sludge and the supernatant water by the baffle plate 61 in the collection pot 6B, the clarity of the supernatant water and the treated water can be maintained. Further, the baffle plate 61 can effectively prevent the sludge 11 from being rolled up when the sludge discharge pump P2 is activated.

  According to this embodiment, a cyclone is used to save space, and the improvement of the collection pot 6 solves problems such as separation efficiency and a reduction in the concentration of the drawn slurry. The treated water is clarified by pulling out the slurry, and the slurry is concentrated in the collection pot. In addition to reducing the water content of the slurry and simplifying the subsequent dehydration process, the supernatant water containing no slurry from the recovery pot can be used as the cyclone-treated water. Moreover, only the water pump used for cyclone separation is sufficient, and a separate power source is not required for the recovery pot.

  According to these embodiments, a solid-liquid separation device that can further improve the separation efficiency of solid matter in a space-saving manner is provided.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

2 ... Raw water tank, 3 ... Cyclone (centrifuge), 4 ... treated water discharge pipe, 5 ... slurry discharge pipe, 6, 6A, 6B ... recovery pot, 6a ... large diameter upper part, 6c ... reduced diameter lower part, 6f ... Discharge port, 7 ... supernatant discharge tube, 8 ... sludge discharge tube, 9 ... partitioning member, 10 ... slurry pot, 10a ... large diameter upper part, 10c ... reduced diameter lower part, 10f ... discharge port,
DESCRIPTION OF SYMBOLS 12 ... Controller, 13 ... Aggregation unit, 14 ... Drug injection device, 15 ... Stirrer, 16 ... Second cyclone, 17 ... Second treated water discharge pipe, 18 ... Second slurry discharge pipe, 19 ... First 2 recovery pots, 20 ... second supernatant discharge pipe, 23 ... small volume recovery pot, 24 ... supernatant discharge pipe, 27 ... large volume recovery pot, 28 ... supernatant discharge pipe, 31 ... partitioning member, 32 ... through hole, 40 ... dehydrator, 41 ... drug injection device, 61 ... baffle plate,
P1 ... water pump, P2 ... sludge discharge pump (pressure feed pump),
V1, V3, V4, V5 ... Sludge valve, V2 ... Supernatant switching valve,
S1, S2 ... sensors,
L1 ... Raw water supply line, L2 ... Treatment water discharge line, L3 ... Sludge discharge line, L4 ... Supernatant discharge line, L5 ... Supernatant return line,
L6 ... second treated water discharge line, L7 ... second sludge discharge line, L8 ... second supernatant discharge line,
L9, L10 ... sludge discharge line,
L11: Aggregate discharge line,
L12: Aggregate return line (sludge return line).

Claims (20)

Centrifugal separation is performed by swirling raw water containing solids and having a slurry discharge pipe for discharging the slurry containing solids at the bottom and a treated water discharge pipe for discharging the treated water to the outside. Machine,
A raw water tank for storing raw water,
A water pump for pumping the raw water in the raw water tank to the centrifuge;
A recovery pot in which the slurry discharge pipe of the centrifuge is inserted and the solid matter contained in the slurry discharged from the slurry discharge pipe is settled in the form of sludge;
A supernatant discharge pipe inserted into the upper portion of the recovery pot and discharging the supernatant water in the recovery pot;
A sludge discharge pipe for discharging sludge settled at the bottom of the recovery pot;
A solid-liquid separation device, wherein a gap is provided between a lower end of the slurry discharge pipe and a bottom portion of the recovery pot, and the lower end of the slurry discharge pipe is lower than a lower end of the supernatant discharge pipe.   Furthermore, it has a partition member provided between the slurry discharge pipe and the supernatant discharge pipe in the recovery pot, and a gap is provided between the lower end of the partition member and the bottom of the recovery pot. The device of claim 1.   The apparatus according to claim 1, wherein the supernatant discharge pipe is connected to the treated water discharge pipe. Furthermore, a supernatant return line branched from the supernatant discharge pipe and connected between the supernatant discharge pipe and an upstream line of the water pump;
A switching valve that is provided where the supernatant return line branches off from the supernatant discharge pipe, and switches a flow path between the supernatant discharge pipe and the supernatant return line;
4. The apparatus of claim 3, comprising:   The apparatus according to claim 1, further comprising a second centrifuge connected to a downstream line of the supernatant discharge pipe.   6. The apparatus according to claim 5, further comprising a drug injection device and a stirring device provided in the supernatant discharge pipe upstream of the second centrifuge.   The apparatus according to claim 1, wherein a plurality of recovery pots are connected in series, and a downstream recovery pot of the plurality of recovery pots has a smaller volume than an upstream recovery pot. .   The apparatus according to any one of claims 1 to 6, wherein a plurality of recovery pots are connected in series, and a downstream recovery pot of the plurality of recovery pots has a larger volume than an upstream recovery pot. .   A plurality of centrifuges are connected in parallel to the water pump, and a plurality of slurry discharge pipes provided in each of the plurality of centrifuges are inserted into one recovery pot. Item 9. The apparatus according to any one of Items 1 to 8.   Furthermore, it has a partition member provided so as to surround the plurality of slurry discharge pipes between the plurality of slurry discharge pipes and the supernatant discharge pipe in the recovery pot, and a lower end of the partition member and the recovery pot The device according to claim 9, wherein a gap is provided between the bottom portion and the bottom portion.   The device according to claim 10, wherein a through hole is formed in the partition member. Centrifugal separation is performed by swirling raw water containing solids and having a slurry discharge pipe for discharging the slurry containing solids at the bottom and a treated water discharge pipe for discharging the treated water to the outside. Machine,
A raw water tank for storing raw water,
A water pump for pumping the raw water in the raw water tank to the centrifuge;
A slurry pot attached in the middle of the slurry discharge pipe, having an inner diameter larger than the inner diameter of the slurry discharge pipe, and reducing the flow rate of the slurry flowing down in the slurry discharge pipe;
A recovery pot in which the slurry discharge pipe is inserted and solids contained in the slurry discharged from the slurry discharge pipe are settled in the form of sludge;
A supernatant discharge pipe inserted into the upper portion of the recovery pot and discharging the supernatant water in the recovery pot;
A sludge discharge pipe for discharging sludge settled at the bottom of the recovery pot;
A solid-liquid separation device comprising: A sludge discharge pump that is provided in the sludge discharge pipe and sucks and discharges sludge in the recovery pot;
A turbidity sensor for measuring the turbidity of treated water flowing through the treated water discharge pipe;
Control means for controlling the driving of the slurry discharge pump based on a measurement signal from the turbidity sensor;
13. The apparatus of claim 12, further comprising:   The apparatus according to any one of claims 12 and 13, wherein a lower end of the slurry discharge pipe is disposed away from a bottom of the recovery pot.   15. The recovery pot according to any one of claims 12 to 14, wherein the recovery pot has a reduced diameter lower portion whose inner diameter gradually decreases, and a discharge port that opens to the reduced diameter lower portion and communicates with the sludge discharge pipe. The apparatus according to item 1.   16. The slurry pot according to claim 12, wherein the slurry pot has a reduced diameter lowering portion whose inner diameter gradually decreases, and a discharge port that opens to the reduced diameter lower portion and communicates with the slurry discharge pipe. The apparatus according to item 1.   The apparatus according to any one of claims 12 to 16, further comprising a dehydrator that is provided downstream of the sludge discharge pump and dewaters sludge discharged from the recovery pot.   The apparatus further comprises a drug injection unit provided in a front stage of the centrifuge and having a function of injecting the flocculant into the raw water sent from the raw water tank to the centrifuge and stirring the flocculant. The apparatus according to any one of 12 to 17.   The apparatus according to any one of claims 12 to 18, further comprising a sludge return line for returning sludge sent from the recovery pot to the raw water tank by driving the sludge discharge pump.   The apparatus according to any one of claims 12 to 19, further comprising a baffle plate for preventing sludge from floating in the collection pot.

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