JP4853683B2 - Treated water reuse system using discharge head - Google Patents

Description

  The present invention relates to a reuse system that purifies sewage such as sewage, human waste, community wastewater, or factory wastewater with a wastewater treatment facility, and uses the treated water as industrial water after advanced treatment. The present invention relates to a treated water reuse system that uses a discharge drop to perform stock solution supply, filtration operation, and recovery of a power source using a discharge weir.

  Conventionally, sewage from sewage treatment plants and human waste treatment plants has been concentrated and biologically processed, such as sedimentation, and the separated water that has been subjected to solid-liquid separation is sterilized and disinfected and released into rivers and the sea. In Japan, where water resources are scarce, it is expected that the discharged water will be used as agricultural water and industrial water as secondary treated water. In recent years, small hydro turbine generators that use the potential energy of water in rivers, reservoirs, etc. have been reviewed as a power generation facility that is free from environmental pollution and is not affected by weather conditions, and the water used for turbine generators is normally discharged. ing. For example, Patent Document 1 discloses a water purification treatment facility in which a hydroelectric generation device and a membrane filtration device are provided in a water conduit that takes water from a river or the like as a hydroelectric generation device that covers a part of the power of the water purification treatment facility. Further, Patent Document 2 proposes a self-siphon type water turbine generator that uses a bleed action of an ejector by installing a water wheel in a discharge weir such as a river or a reservoir. And the downflow type filter which accommodated the fiber filter medium a little heavier than water and suspended the stirring blade on the tank bottom is also disclosed in Patent Document 3, and contains the fiber filter medium having a specific gravity of about 0.9. An upward flow filter having a stirring blade suspended from the bottom of the tank is also disclosed in Patent Document 4.

Japanese Patent No. 3632648 (Claim 1, FIG. 1) Japanese Patent Laying-Open No. 2008-88896 (paragraph number 0011, FIG. 1) JP 2000-126515 A (paragraph number 0007, FIG. 1) Japanese Patent No. 3109644 (paragraph number 0005, FIG. 1)

Conventional small hydro turbine generators that utilize the difference in water level between rivers and reservoirs can effectively utilize unused energy and clean natural energy, thereby contributing to reduction of environmental load and power consumption. Water treatment facilities with hydroelectric generators and membrane filtration devices installed in water conduits that draw water from rivers, etc. have the advantage of being able to obtain power while performing water purification using the pressure of raw water. The treated water purified at the palm urine treatment plant contains fine suspended solids, and the membrane filtration device is clogged, needs to be washed frequently, and may deteriorate early. A self-siphon turbine generator that uses an ejector's bleed action by installing a water wheel in a discharge weir such as a river or a reservoir uses a small drop of water to generate a siphon action with a simple pipe structure to automatically operate. Is possible. In addition, the sealed filtration tank containing the fiber filter medium has an advantage that the filter medium can be easily washed, and that fine filtration can be performed even with treated water containing many fine suspended matters.

This invention applies the technology of a self-siphon type water turbine generator that uses the discharge drop of rivers, reservoirs, etc., and further treats the treated water purified by the wastewater treatment facility using the discharge drop of the discharge weir. Provide a treated water reuse system that uses a drop head to install a filtration device, supply undiluted liquid in a filtration tank, perform filtration operations, clean filter media, and recover a power source.

In a filtration device that supplies treated water from a wastewater treatment plant, etc. to a filtration tank containing filter media and performs advanced treatment and reuses, a water supply pipe connected to the filtration tank is straddled over a discharge weir, and the start end of the water supply pipe is Submerged in the upper tank and formed into a siphon, and the treatment tank and the washing drain pipe of the filtration tank are placed at a position lower than the water level of the upper tank, and a water receiving tank that receives the overflow water from the discharge weir is installed in the lower tank Then, the ejector pipe provided with the intake ejector in the water receiving tank is suspended, and the extraction pipe connected to the intake ejector is connected to the water supply pipe. If the overflow water from the discharge weir flows into the water receiving tank, it is suspended in the water receiving tank. The discharged ejector pipe becomes negative pressure due to falling water, the air accumulated in the feed water pipe is sucked by the ejector action of the intake ejector, and the discharged water can be flowed from the feed water pipe into the filtration tank by the siphon action.

Use a discharge weir to suspend a water turbine equipped with a generator in the upper water tank, lay a water pipe suction pipe over the discharge weir, submerge in the lower water tank, and connect a bleed pipe connected to the intake ejector of the water receiving tank It is branched and connected to the suction pipe. By using the extraction action of the intake ejector that starts the filtration device, the turbine can be started and the turbine can generate electricity.

The filtration device installed in the vicinity of the lower water tank is an agitator installed on the bottom of the filtration tank with an air motor, and the exhaust pipe of the air motor is connected to the filtration tank near the blades of the agitator to clean the filter media layer. At this time, since the exhaust air of the air motor is ejected while stirring the filter medium with the stirrer, a cleaning effect by synergistic action of mechanical stirring and air stirring is obtained, and the filter medium can be regenerated with low output.

An air compressor is connected to the drive air pipe that supplies compressed air to the air motor, the power supply line of the turbine generator is connected to the air compressor, and a compressed air tank is attached to the drive air pipe. The stirrer can be driven while transmitting the power to the air compressor using the machine and preventing the pulsation of the supply pressure of the compressed air to the air motor. It is also possible to store compressed air in the compressed air tank when the filter medium layer is not stirred and washed.

The filter medium to be stored in the filter tank is a fiber filter medium, a treated water pipe is drawn down from the top of the filter tank, and the treated water pipe is withdrawn from the treated tank at the bottom of the filter tank. Are connected to each other, and the stock solution of the filtration device is supplied using the discharge drop of the discharge weir, and the fiber filter medium rich in compressibility reduces the porosity between the filter medium layers and traps and removes fine suspended substances. And advanced processing is possible. If the filter medium layer is stirred, the fiber filter medium can be easily dispersed and developed, and the trapped suspended substances held in the fiber gaps can be easily peeled off and dropped off. The cleaning power can be reduced, the filter medium is not deteriorated during cleaning, and the durability of the filter medium is prolonged.

The filtration tank is configured as a sealed filtration tank containing floating filter media, and a water supply pipe that supplies wastewater treated water to the bottom of the filtration tank and a treated water pipe that draws out advanced treated water at the top of the filtration tank are connected. If the treated water pipe is branched and the washing water drain pipe is connected, it is possible to form a filter medium layer by upward flow and efficiently fill the gaps between the filter media. If stirring is performed from below the filter medium layer, the trapped suspended substance held in the gaps of the filter medium can be easily peeled off and dropped, and the cleaning power can be reduced.

A water receiving tank that receives overflow water by straddling a water supply pipe connected to the filtration tank and a suction pipe of a water turbine equipped with a generator, using the discharge head of the discharge weir at a wastewater treatment plant, etc. Since the bleed pipe connected to the intake ejector is connected to the suction pipe of the turbine and the suction pipe of the turbine to generate a siphon action, if the drainage water overflows the discharge weir, the extraction action of the intake tank will generate the extraction action. Thus, the air remaining in the water supply pipe of the filter tank and the suction pipe of the water turbine is discharged, and the filtration operation of the filter tank and the power generation by the water wheel can be started. Even if the water level in the upper tank is lowered and the filtration device and the water turbine are stopped, if the water level rises, an extraction action is generated in the intake ejector, and the filtration device and the water wheel can be automatically operated. Fine suspended solids can be separated without wastefully discharging treated water from sewage treatment plants, etc., and can be effectively used for industrial water etc. as advanced treated water, and at the same time, the recovered power can be used as a power source for washing filter media Can also be used. When the filter medium layer is not stirred and washed, compressed air can be stored in the compressed air tank, and electric power can be stored in the capacitor or diverted to incidental facilities.

It is a flowchart of the treated water reuse system using the discharge drop concerning this invention. Similarly, it is a longitudinal cross-sectional view of the filtration tank installed in the vicinity of a lower water tank. Similarly, it is a flowchart which operates the filtration apparatus installed in the lower water tank side. Similarly, it is a flowchart which operates the waterwheel suspended from the upper water tank. Similarly, it is a longitudinal cross-sectional view of the upflow type hermetic filtration device of another embodiment of the filtration device. It is the front view and side view of a floating filter medium similarly accommodated in an upward flow type filtration tank. Similarly, it is a side view of a floating filter medium of another embodiment.

  An embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a flowchart of a treated water reuse system using a discharge drop, and stores treated water in a sewage treatment plant or the like that has performed solid-liquid separation or the like. A discharge weir 1 is disposed between the upper water tank A and a lower water tank B that discharges treated water, and a filtration device 2 is installed in the vicinity of the lower water tank B. A filtration tank 2 is installed in the filtration device 2, a water supply pipe 4 for supplying treated water from a sewage treatment plant or the like is connected to the top of the filtration tank 3, and the water supply pipe 4 of the filtration tank 3 is formed in a siphon shape. The pipe top portion 4 a is straddled over the discharge weir 1, and the start end portion 4 b is suspended from the upper water tank A. An axial-flow type water turbine 6 equipped with a generator 5 is suspended in the upper water tank A, and a top portion 7a of a suction pipe 7 connected to the water turbine 6 is straddled over the discharge weir 1, and a rear end portion 7b is formed in the lower portion. The water wheel 6 and the suction pipe 7 are formed in a siphon shape depending on the water tank B. The rear end portion 7b of the suction pipe 7 of the water turbine 6 opens at a position lower than the suction port 6a of the water turbine 6 of the upper water tank A and is submerged in the lower water tank B. A water receiving tank 8 that receives the overflow water from the discharge weir 1 is installed in the lower water tank B, and an intake ejector 10 is provided in an ejector pipe 9 that hangs down from the bottom of the water receiving tank 8. If the wastewater treated water in the upper water tank A overflows the discharge weir 1, the wastewater treated water in the upper water tank A flows into the water receiving tank 8 and flows down the ejector pipe 9. The ejector tube 9 becomes negative pressure due to falling water, and causes the intake ejector 10 to extract air.

FIG. 2 is a filtration tank installed in the vicinity of the lower water tank, and a filter 11 for preventing a filter medium outflow is stretched over the filter tank 3, and a filtration chamber 13 for forming a filter medium layer 12 on the upper part of the screen 11, A water collection chamber 14 is formed at the bottom of the screen 11 to allow the treated water from which fine suspended solids have been removed by the filter medium layer 12 to flow, and the washing drainage obtained by stirring and washing the filter medium layer 12 is allowed to flow over the upper periphery of the filter tank 3. A drain trough 15 is provided. A stirrer 17 having an air motor 16 disposed on the bottom of the filtration tank 3 is erected, and blades 17a of the stirrer 17 are projected from the filtration chamber 13 above the screen 11. A treated water pipe 18 and a washing water supply pipe 19 branched from the water supply pipe 4 are connected to the water collection chamber 14 of the filtration tank 3, and are connected to the side wall of the filtration chamber 13 constituting the filtration tank 3. A cleaning drain pipe 20 is connected to the drain trough 15 of the section. The treated water pipe 18 connected to the filtration tank 3 and the connection ports 18a and 20a of the cleaning drain pipe 20 are opened at a position lower than the lowest water level when the treated water stored in the upper water tank A is treated by the filtration device 2. . As the filter medium forming the filter medium tank 12, a known filter medium having a specific gravity heavier than water can be used.

As shown in FIG. 2, an air compressor 22 is connected to a driving air pipe 21 connected to an air motor 16, and an agitator 17 in which an exhaust pipe 23 connected to the air motor 16 is protruded from the filtration chamber 13 of the filtration tank 3. Connected to the vicinity of the blade 17a. A compressed air tank 24 is branched from the drive air pipe 21 connected to the air compressor 22 to prevent pulsation of the compressed air pressure supplied to the air motor 16. In the embodiment of the present invention, the upper part of the drainage trough 15 is covered and the filtration tank 3 is a sealed type. However, the water supply pipe 4 for supplying treated water may be suspended from the top of the filtration tank 3 to be an open type. It is. A water supply valve V6 and an air discharge valve V33 are provided in the water supply pipe 4 near the filtration tank 3, and a treatment water valve V7 is provided in the treatment water pipe 18 connected to the water collecting chamber 14 of the filtration tank 3. A water supply valve V9 is provided in the washing water supply pipe 19 that branches from the water supply pipe 4 and supplies the washing water to the filtration tank 3, and a drain valve V8 is provided in the washing drain pipe 20 that discharges the washing waste water that has washed the filter medium in the filtration tank 3. It is.

FIG. 3 is a flowchart for operating the filtration device installed on the lower water tank side, and an extraction pipe 25 interposing an ejector valve V3 is connected to an intake ejector 10 of an ejector pipe 9 hanging from the water receiving tank 8. The rear end of the trachea 25 is connected to the top 4a of the water supply pipe 4 from above. A bleed valve 25 for discharging the air staying at the pipe top 4a is interposed in the bleed pipe 25 in the vicinity of the water supply pipe 4, and a full water detector LS1 for detecting rising water at the pipe top 4a. When the filtration tank 3 is operated, the ejector valve V3 and the extraction valve V4 interposed in the extraction pipe 25 are opened, and the treated water in the upper water tank A overflows the discharge weir 1 and flows into the water receiving tank 8 in the lower water tank B. For example, the intake ejector 10 is caused to bleed, the air stored in the pipe top 4a of the water supply pipe 4 is discharged from the bleed pipe 25, and the treated water in the upper water tank A is caused to flow into the water supply pipe 4 to detect the exhaust of the air. This is detected by the instrument LS1. If the siphon action is generated by the discharge of air from the water supply pipe 4 and the water supply valve V6 is opened, the treated water in the upper water tank A is supplied to the filtration tank 3, and the fine suspended matter can be separated and advanced treatment can be performed. Even if the water level of the upper water tank A falls and the filtering action of the filter tank 3 stops, if the water level rises again and overflows the discharge weir 1, the wastewater treated water flows into the water receiving tank 8 and the ejector pipe 9 As a result, an extraction operation is generated in the intake ejector 10, and the supply pump of the filtration tank 3 is not required regardless of the fluctuation of the water level, and an automatic operation becomes possible. In addition, the flowmeter Q2 which measures the supply flow volume to the filtration apparatus 2 and the vacuum breaker valve V32 which stops water supply are provided in the pipe top part 4a of the water supply pipe 4. FIG.

FIG. 4 is a flowchart for operating the water turbine suspended in the upper water tank. The extraction pipe 25 connected to the intake ejector 10 for generating the suction action of the ejector pipe 9 branches from the rear of the ejector valve V3, and the water turbine 6 The suction pipe 7 is connected to the pipe top 7a from above. A bleed valve 25 that discharges air remaining in the pipe top portion 7 a is interposed in the bleed pipe 25 near the suction pipe 7 connected to the water turbine 6. A flow rate adjusting valve V1 for adjusting the pumping amount of the water turbine 6, a flow meter Q1 for measuring the discharge flow rate of the water turbine 6, and a vacuum breaker valve V31 for stopping the water turbine 6 are provided at the pipe top 7a of the suction pipe 7. . When the water turbine 9 is operated, if the ejector valve V3 and the bleed valve V2 provided in the bleed pipe 25 are opened and the treated water in the upper water tank A flows into the water receiving tank 8, the bleed action is generated in the intake ejector 10. The air stored in the pipe top part 7a of the suction pipe 7 is discharged, and the suction pipe 7 becomes negative pressure. At the same time, the air in the water turbine 6 is also sucked into a negative pressure, the water inside the water turbine 6 rises and flows into the suction pipe 7, and siphon action is generated by the liquid movement of the rear end 7 b where the suction pipe 7 is suspended. Let The water turbine 6 is driven by the siphon action of the suction pipe 7, and the power generator 5 linked to the water turbine 6 is operated to start power generation.

As shown in FIG. 1, in the embodiment of the present invention, the power supply line 39 of the generator 5 is connected to the air compressor 22, and power is transmitted to the air compressor 22 using the water turbine 6, and the compressed air tank 24. Thus, the stirrer 17 can be operated by driving the air motor 16 disposed in the filtration tank 3 from the air compressor 22 while preventing the pulsation of the compressed air pressure. Compressed air can be stored in the compressed air tank 24 when the filter medium layer 12 is not stirred and washed, and electric power can be stored in a capacitor, or can be diverted to ancillary equipment. Even if the operation of 6 is stopped, if the water level of the upper water tank A rises again and overflows the discharge weir 1, the treated water flows into the water receiving tank 8 and the bleed action occurs in the intake ejector 10 of the ejector pipe 9. However, the water turbine 6 can be automatically operated regardless of the fluctuation of the water level. If the water turbine 6 is suspended in the upper water tank A on the high water level side, the rear end of the suction pipe 7 on the low water level side even if the water level difference between the upper water tank A on the high water level side and the lower water tank B on the low water level is small. 7b can be submerged to cause siphon action and can be used with a low head.

  FIG. 5 shows an upflow-type sealed filtration device according to another embodiment of the filtration device. The floating filter medium is stored in a sealed-type filtration tank 26 and treated water is supplied in an upward flow. A filter medium layer 27 is formed on the half. A water supply pipe 28 is connected to the tank bottom of the filtration tank 26, and a treated water pipe 30 having a water collection nozzle 29 disposed at the top, and the wastewater treated water of the upper water tank A is supplied from the tank bottom. Highly treated water from which suspended matter has been separated is extracted from the top. A stirrer 32 in which an air motor 31 is disposed is erected on the bottom of the filtration tank 26, and a blade 32 a of the stirrer 32 protrudes near the lower side of the filter medium layer 27. A driving air pipe 33 is connected to the air motor 31, and an exhaust pipe 34 connected to the air motor 31 and a washing water supply pipe 35 branched from the water supply pipe 28 are formed on the side wall of the filtration tank 26 near the blade 32 a of the stirrer 32. Each is connected. Water supply valves V6 and V9 are interposed in the branched water supply pipe 28 and the wash water supply pipe 36, respectively. A washing drain pipe 36 is branched from the treated water pipe 30, and a treated water valve V 7 and a drain valve V 8 are interposed in the treated water pipe 30 and the washing drain pipe 36. The treated water pipe 30 connected to the filtration tank 26 is opened at a position lower than the lowest water level when the treated water stored in the upper water tank A is treated in the filtration tank 26.

FIG. 6 is a front view and a side view of a floating filter medium housed in an upward flow filtration tank, and the filter medium forming the filter medium layer 27 in the filter tank 26 shown in FIG. A mole filter medium 37 having a specific gravity lighter than water is constituted by a filament yarn 37c of radial short fibers fixed to a nylon core yarn 37a and a presser yarn 37b. The Mole filter medium 37 forming the filter medium layer 12 efficiently and uniformly fills the gaps between the Mole filter mediums 37, 37, and reduces the porosity between the filter medium when forming the filter medium layer. The treated water injected into the filtration tank 3 compresses the filter medium layer 12 to further reduce the porosity between the molding filter media 37 and 37, and the suspended water in the treated water that preferentially passes through the gap between the molding filter media 37 and 37. The turbid material is captured and removed by the flower yarn 37c between the filter medium-filled short fibers. Since the Mole filter medium 37 has very little dropout of the flower yarn 37c at the time of washing, the filter medium has high durability, and a stable filtration operation can be performed over a long period of time.

FIG. 7 shows a floating filter medium according to another embodiment, which uses a filter medium in which a composite fiber having a specific gravity of 0.7 to 1.0 and 3 to 50 mm ^□ is fused. The fiber filter medium 38 includes a first filament 38a having a synthetic resin fineness of 18 to 65 denier, a second filament 38b having a fineness of 3 to 10 denier, and a third filament 38c having a fineness of 1.5 to 6 denier. The web is heat-sealed by blending to form a porosity of approximately 95%. When the filter medium layer 27 is formed with the fiber filter medium 38 and the filter medium becomes clogged during the filtration operation, the thick filament secures the void formed by the thin filaments against the increase in the filtration pressure, and this action also works. In addition, it enables long-time operation. Even when clogging and cleaning, or when the filter medium layer 27 is formed, the gaps are uniform and cleaning and regeneration are easy. The floating filter medium can also be used as a granular filter medium. If a granular foamed filter medium made of expanded polystyrene having a specific gravity of 0.05 and a particle diameter of 0.5 to 2.0 mmφ is used, the porosity decreases. However, if the filter medium layer 27 is formed by a gentle upward flow of the treated water flowing into the filtration tank 26 and the exhaust compressed air of the air motor 31 is supplied to the vicinity of the blades 32a of the stirrer 32 while operating the stirrer 32, stirring washing Therefore, the fine particles that are easily diffused and trapped can be separated and discharged from the filter medium layer 27.

Example 1
In the treated water reuse system of FIG. 1, the procedure for operating the filtration device installed in the treatment plant will be described. The treated water in the upper tank A is full, the water receiving tank installed in the lower tank B over the discharge weir 1. 8 flows into the ejector pipe 9, a negative pressure is generated by the falling water flowing down the ejector pipe 9, and the air extraction action is generated in the intake ejector 10 to suck the air in the extraction pipe 25. In the above situation, the start of single operation of the filtration device
(1) At the start of filtration operation a. A treated water valve V7 of the treated water pipe 18 attached to the filtration tank 3, a drain valve V8 of the washing drain pipe 20, a feed valve V9 of the washing water feed pipe 19, and a vacuum breaker valve V32 provided on the pipe top 4a of the feed water pipe 4, And the air discharge valve V33 provided in the water supply pipe 4 near the filtration tank 3 is closed,
b. The ejector valve V3 of the extraction pipe 25 connected to the intake ejector 10, the extraction valve V4 of the water supply pipe 4, and the water supply valve V6 of the water supply pipe 4 near the filtration tank 3 are opened.
c. When the receiving tank 8 receives the overflow water from the discharge weir 1,
d. A negative pressure is generated by the falling water of the ejector pipe 9 where the discharged water flows down, and the extraction action of the intake ejector 10 is started, and the air accumulated in the pipe top 4a of the water supply pipe 4 is sucked.
e. The completion of air discharge is detected by the full water detector LS1 provided at the pipe top 4a of the water supply pipe 4,
f. When the treated water valve V7 of the filtration tank 3 is opened, the discharge of treated water is started.
g. If the extraction valve V4 of the water supply pipe 4 and the ejector valve V3 of the extraction pipe 25 are closed,
h. The discharge operation of the advanced treated water which processed the fine suspended matter with the filtration apparatus 2 is attained.

(2) During washing drainage a. Open the water supply valve V6 and the treated water valve V7 of the filtration tank 3,
b. The ejector valve V3 of the extraction pipe 25, the extraction valve V4 of the water supply pipe 4, the cleaning drainage valve V8 and the cleaning water supply valve V9 of the filtration tank 3, and the vacuum breaker valve V32 and the air discharge valve V33 of the water supply pipe 4 are closed c. During continuous operation of advanced treatment of treated water in filtration tank 3,
d. Close the water supply valve V6 and the treated water valve V7 of the filtration tank 3,
e. The washing drain valve V8 and the washing water supply valve V9 of the filtration tank 3 are opened.
f. If the drive valve V21 of the air motor 16 and the air discharge valve V33 of the water supply pipe 4 are opened,
g. Along with the rotation of the stirrer 17, a synergistic effect of cleaning that can start stirring cleaning with the exhaust air of the air motor 16 is obtained.

(3) Normal filtration operation after washing drainage a. Open the drainage valve V8 and the cleaning water supply valve V9 of the filtration tank 3, the drive valve V21 of the air motor 16, and the air discharge valve V33 of the water supply pipe 4; b. The ejector valve V3 of the extraction pipe 25, the extraction valve V4 of the water supply pipe 4, the water supply valve V6 of the filtration tank 3, the treated water valve V7, and the vacuum break valve V32 of the pipe top 4b of the water supply pipe 4 are closed c. During washing drainage operation,
d. The drive valve V21 of the air motor 16 and the air discharge valve V33 of the water supply pipe 4 are closed, and the cleaning / drainage valve V8 and the cleaning water supply valve V9 of the filtration tank 3 are closed.
e. If the water supply valve V6 of the filtration tank 3 and the treated water valve V7 of the treated water pipe 18 are opened, the normal advanced treated water can be discharged.

(4) When the filtration device is shut down a. Open the water supply valve V6 and the treated water valve V7 of the filtration tank 3,
b. The ejector valve V3 of the extraction pipe 25, the extraction valve V4 of the water supply pipe 4, the drain valve V8 of the cleaning drain pipe 20 of the filtration tank 3, the cleaning water supply valve V9 of the cleaning water supply pipe 19, the drive valve V21 of the air motor 16, and the water supply pipe No. 4 air discharge valve V33 and the vacuum break valve V32 at the top 4a of the water supply pipe 4 are closed c. During normal discharge operation,
d. Close the water supply valve V6 and the treated water valve V7 of the filtration tank 3,
e. The vacuum break valve V32 of the water supply pipe 4 is opened.
f. The operation can be stopped by stopping the water supply to the filtration tank 3 by the vacuum breakage of the water supply pipe.

Example 2
In the treated water reuse system of FIG. 1, the procedure for operating the water turbine installed in the treatment plant will be described.
1) Open the flow rate adjustment valve V1 and the extraction valve V2 of the suction pipe 7 of the water turbine 6 and the ejector valve V3 of the extraction pipe 25.
2) When the water receiving tank 8 receives the overflow water from the discharge weir 1,
3) Negative pressure is generated by the falling water of the ejector pipe 9 where the discharged water flows down, the bleed action of the intake ejector 10 is started, the air accumulated at the top of the suction pipe 7 is sucked, a siphon is formed, and the turbine discharge power generation operation is started. To do.

Example 3
In the treated water reuse system using the discharge drop shown in FIG.
a. Washing of the extraction valve V2 at the top 7a of the suction pipe 7 of the water turbine 6, the ejector valve V3 of the extraction pipe 25, the extraction valve V4 of the water supply pipe 4, the water supply valve V6 of the filtration tank 3, the treated water valve V7, and the filtration tank 3 The drain valve V8, the flush water supply valve V9, the vacuum break valve V31 of the water wheel 6 and the vacuum break valve V32 of the water pipe 4 are closed, and the flow rate adjustment valve V1 of the suction pipe 7 of the water wheel 6 is opened b. During the water turbine alone operation,
c. The extraction valve V2 at the pipe top 7a of the suction pipe 7 of the water turbine 6 and the water supply valve V6 and the extraction valve V4 of the water supply pipe 4 are opened.
d. The air in the water supply pipe 4 of the filtration tank 3 is extracted by the intake pressure of the suction pipe 7 of the water turbine 6.
e. The completion of air discharge is detected by the full water detector LS1 of the water supply pipe 4,
f. If the water supply valve V6 and the treated water valve V7 of the filtration tank 3 are opened, the discharge of the normal advanced treated water is started.
g. By closing the extraction valve V2 of the suction pipe 7 of the water turbine 6 and the extraction valve V4 of the water supply pipe 4, it is possible to perform the turbine discharge power generation operation and the normal altitude treated water discharge operation.

  The treated water reuse system using a discharge drop according to the present invention uses a discharge drop of a discharge weir such as a wastewater treatment plant to connect a water supply pipe of a filtration tank and a suction pipe of a water turbine equipped with a generator to the discharge weir. The air compressor is installed on the air motor that drives the stirrer of the filtration tank, and the extraction pipe connected to the intake ejector of the water receiving tank that receives the overflow water is connected to the suction pipe of the turbine and the suction pipe of the turbine. If the treated wastewater such as sewage overflows the discharge weir, the filtration operation of the filtration tank and the power generation by the water wheel can be started, and the water level of the upper tank is lowered and filtered. Even if the device and the water turbine are stopped, if the water level rises, the suction action is generated in the intake ejector, and the filtration device and the water turbine can be automatically operated. Therefore, fine suspended solids can be separated without wastefully discharging treated water from a sewage treatment plant, etc., and can be effectively used for industrial water etc. as advanced treated water. It can also be used as a source. Compressed air can be stored in the compressed air tank when the filter medium layer is not stirred and washed, and electric power can be stored in a capacitor, or can be diverted to incidental equipment.

DESCRIPTION OF SYMBOLS 1 Discharge weir 3, 26 Filtration tank 4, 28 Water supply pipe 4b Starting end part 5 Generator 6 Water wheel 7 Suction pipe 8 Water receiving tank 9 Ejector pipe 10 Intake ejector 16 Air motor 17, 32 Stirrer 17a, 32a Blade | wing 18, 30 Treated water pipe 20, 36 Washing drain pipe 19, 35 Washing water supply pipe 21, 33 Drive air pipe 22 Air compressor 23, 34 Exhaust pipe 24 Compressed air tank 25 Extraction pipe 39 Feeding line A Upper water tank B Lower water tank

Claims (6)

In a filtration device that supplies treated water from a wastewater treatment plant or the like to a filtration tank (3) that contains filter media and performs advanced treatment and reuses, a water supply pipe (4) connected to the filtration tank (3) is connected to a discharge weir (1 ), The start end (4b) of the water supply pipe (4) is submerged in the upper water tank (A) to form a siphon, the treated water pipe (18) of the filtration tank (3) and the washing drain pipe (20 ) Is disposed at a position lower than the water level of the upper water tank (A), and a water receiving tank (8) for receiving the overflow water of the discharge weir (1) is installed in the lower water tank (B). The discharge pipe head (9) provided with the intake ejector (10) is suspended and the bleed pipe (25) connected to the intake ejector (10) is connected to the water supply pipe (4). Treated water reuse system. A water turbine (6) mounted with a generator (5) is suspended from the upper water tank (A), and a suction pipe (7) of the water wheel (6) is straddled over a discharge weir (1). The discharge drop according to claim 1, wherein the extraction pipe (25) connected to the intake ejector (10) of the water receiving tank (8) is branched and connected to the suction pipe (7). Treated water reuse system. An air motor (16) is disposed in the stirrer (17) standing on the bottom of the filtration tank (3), and the exhaust pipe (23) of the air motor (16) is filtered in the vicinity of the blade (17a) of the stirrer (17). The treated water reuse system using a discharge drop according to claim 1 or 2, characterized by being connected to a tank (3). The air compressor (22) is connected to the driving air pipe (21) connected to the air motor (16), and the power supply line (39) of the generator (5) of the water turbine (6) is connected to the air compressor (22). And the compressed water tank (24) was attached to the drive air pipe (21), The treated water reuse system using the discharge drop of Claim 3 characterized by the above-mentioned. A fiber filter medium is accommodated in the said filtration tank (3), the water supply pipe (4) of drainage treated water is hung on the top part of the filtration tank (3), a treated water pipe (18) is filtered at the lower part of the filtration tank (3), and filtered. The treated water reuse system using a discharge drop according to any one of claims 1 to 4, wherein a washing water supply pipe (19) is connected to an appropriate place of the tank (3). The said filtration tank is comprised in the sealed filtration tank (26) which accommodated the floating filter medium, a water supply pipe (28) in the tank bottom of a filtration tank (26), and a treated water pipe (30 in the top part of a filtration tank (26)) 5), the treated water pipe (30) is branched, and the washing water drain pipe (36) is connected, The treatment using the discharge drop according to any one of claims 1 to 4 Water reuse system.