JP2013006133A - Liquid treatment apparatus and liquid treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently recover suspended matters removed by flotation separation without providing a device requiring a large power such as a liquid pump nor a dynamic machine apparatus such as a sweeping mechanism.SOLUTION: A RO retentate that contains ozone microbubbles 29 is supplied in a lower part of a contact tank 5 of an airtight structure to ozonate the retentate and to float and separate the suspended matters 32. A valve 10, a valve 14, and a valve 21 are closed to pump up the treated water to a washing liquid tank 15 installed in a height by a supply pressure of the RO retentate, and the valve 14, the valve 16, and the valve 21 are opened to sprinkle water to the contact tank 5 wall surfaces from a liquid header 24. The suspended matters 32 are extruded toward a recovery device 23 by the flow of washing water toward the suspended matters 32 from a wall surface, and recovered and removed.

Description

  The present invention relates to a liquid processing apparatus and a liquid processing method, and more particularly, to a liquid processing apparatus and a liquid processing method suitable for removing a suspension.

  In sewage membrane treatment facilities that combine membrane separation activated sludge process (MBR) and reverse osmosis (RO) membrane filtration, MBR treated water that does not permeate the RO membrane, that is, RO membrane treated concentrated water, is separated from organic matter, etc. Drained as concentrated water containing the substance to be decomposed. Concentrated water for RO membrane treatment has a high organic matter concentration, phosphorus, and nitrogen concentration, and therefore, as shown in Non-Patent Document 1, for example, it is drained via a wastewater treatment facility to preserve the environment. In this concentrated water treatment, organic substances need to be decomposed and removed. As a method for decomposing and removing them, for example, a treatment method combining ozone oxidation and activated carbon adsorption shown in Non-Patent Document 2 is known.

  On the other hand, in the MBR, surplus sludge is generated in the biofilm of activated sludge when the first settling basin effluent of sewage is treated. As the excess sludge increases, some of it is withdrawn and landfilled or incinerated, but there is a problem that the sludge treatment cost becomes excessive. It is known that excess sludge can be reduced in volume by solubilizing (solubilizing), returning it to the MBR reaction tank, and using it for biological treatment. As a solubilization method, for example, as shown in Non-Patent Document 3, there is an ozone oxidation method.

  Therefore, ozone is dissolved by using the pressure of the concentrated water separated by the RO membrane, and foamed under reduced pressure by a nozzle to generate ozone microbubbles having a diameter of about 50 μm, and the concentrated water containing the ozone microbubbles is used as a reaction tank. Patent Document 1 discloses a membrane treatment facility that performs oxidative decomposition treatment after being introduced into the process. In this membrane treatment equipment, surplus sludge extracted from the MBR reaction tank is put into the reaction tank to solubilize a part of its organic components and float and separate solid components (turbid components) of the sludge that have not been solubilized. The technique which removes it is used. By raising the water level in the reaction tank, the concentrated components containing ozone microbubbles are entrained in solid components that have not been solubilized and drained from the hopper near the water surface. Further, the solubilized surplus sludge is returned to the MBR reaction tank again for biological treatment.

  In addition, as shown in Patent Document 2, when a scum collector (hopper) is provided near the water surface of the treated water tank and the scum accumulates on the water surface during the water treatment operation of the water to be treated, the water level is raised by valve operation. Then, there is a method in which the suspension is taken into a scum collector together with a part of the water to be treated. This Patent Document 2 shows an example in which a flow path for supplying the water to be treated is installed in the upper part of the water tank, and the water to be treated is supplied along the wall surface to clean the scum adhering to the wall surface. (FIG. 4).

  Moreover, as shown in Patent Document 3, as a device for floating and separating suspended substances, the suspended substance floating on the surface of the floating separation tank is scraped by a scraping mechanism (skimmer) and discharged from the discharge port. There is.

JP 2011-72939 A JP 2009-34558 A Japanese Patent Laid-Open No. 9-234458

“New Water Treatment Using Membrane”, NTS, pp. 303-316, 2000 Masahiro Yoshizawa, et al., “Verification of ultra-high-level treatment in sewerage in Lake Biwa basin (4th report)”, Proceedings of the 45th Sewerage Research Presentation, 743-745, 2008 Hidei Yasui, et al., “Operational example of activated sludge process that does not generate surplus sludge, environmental technology”, VOL. 28, no. 8, pp. 527-531, 1999

  In Non-Patent Document 1, a facility for decomposing and removing organic substances in concentrated water is required in accordance with the water quality standards of the discharge destination. As one of the methods, the treatment with ozone and activated carbon disclosed in Non-Patent Document 2 increases the cost of maintenance due to the consumption of the power for generating ozone and activated carbon. Further, when the treated water of the concentrated water is used as reclaimed water, it is necessary to increase the recovery rate, which is the ratio of the treated water that can be effectively used to the concentrated water.

  In the sewage treatment, it is necessary to concentrate, dewater and dry the excess sludge. However, if the moisture content of the excess sludge is high, the treatment cost increases. Although the solubilization treatment with ozone described in Non-Patent Document 3 has the effect of reducing excess sludge, no consideration is given to reducing the moisture content of excess sludge.

  Patent Document 1 is a treatment method in which ozone gas is mixed with concentrated water to generate microbubbles for the purpose of concentrated water treatment and surplus sludge treatment, and ozone oxidation and suspension separation of suspension are performed in a reaction tank. Suspension flows into the hopper by controlling the water level in the reactor. However, according to the study by the present inventors, the driving force for collecting sludge-derived suspension into the hopper is weak because it is only the shearing force of the flow in the vicinity of the hopper as shown in FIG. It was found that a stagnation region (region A in the figure) occurred, and a large amount of treated water and a long time were required to collect the total amount of the suspension. For this reason, there is a possibility that the water content of the suspension recovered by the hopper is high and the recovery rate of the treated water is lowered.

  In Patent Document 2 (FIG. 4), water to be treated flows down to the wall surface for the purpose of cleaning the wall surface of the treated water tank. In this Patent Document 2, the configuration is not specified for floating and separating the suspended matter, but it is not assumed that ozone microbubbles are generated in the water to be treated and supplied as the water to be treated. That is, ozone is transferred to the gas phase due to collision and scattering on the wall surface, and the ozone utilization efficiency is lowered. In addition, in order for the suspended matter to contact and adhere in the process of ascending the microbubbles, it is necessary to cause the water to be treated, which has generated ozone microbubbles, to flow under the surface of the treated water tank, preferably the lower part of the treated water tank. This is because the floating separation effect of the suspension cannot be obtained. It is possible to use an external water source or treated water flowing out of the treated water tank to clean the wall, but this requires a dynamic pump or other equipment or loop to obtain the water source and water spray head. is there.

  In Patent Document 3, installation of a scraping mechanism (skimmer) and a mechanical device constituting the driving mechanism and maintenance thereof are problems.

  The present invention provides a liquid processing apparatus and a liquid processing method capable of efficiently recovering a suspension without providing a mechanical device such as a liquid pump or a dynamic mechanical device such as a scraping mechanism. The purpose is to do.

  In order to achieve the above object, the present invention provides a contact tank that floats and separates suspended matter from water to be treated by bringing bubbles into contact with the water to be treated, and an opening that opens upward in the contact tank. It has a collector that collects the suspended solids, and in order to float and separate the suspended solids, water to be treated containing air bubbles is pumped from below the contact tank level to the contact tank, and the water level of the contact tank is raised. In the liquid processing apparatus and the liquid processing method in which the suspended matter is collected in the recovery device, when the suspension is floated and separated and the treated water is taken out from the contact tank to the distribution channel, the inside of the contact tank When the suspended matter is collected by the collector, the flow path communicating with the tank provided at a position higher than the water surface of the contact tank and the flow path for supplying the treated water Except for the contact tank, the communication between the inside and outside of the contact tank is cut off, and the water to be treated is supplied into the contact tank. The inside of the tank is pressurized so that the treated water is transferred to the tank. After that, the contact tank is opened to the atmosphere, and the treated water stored in the tank is sprinkled or sprayed so that the suspended matter is at the opening of the collector. It is designed to create a flow that heads.

  In addition, when the suspension is collected by the recovery device, the transfer of the treated water to the tank provided at a position higher than the water surface of the contact tank is changed to the above-mentioned configuration and once at a position lower than the water distribution channel. After the water is stored in the tank provided in the tank (low position tank), the gas phase portion in the low position tank may be pressurized to start from the low position tank.

  In addition, when collecting the suspended matter with a collector, instead of sprinkling or spraying the treated water stored in the tank, the blower creates a flow of the suspended matter toward the opening of the collector. May be.

  According to the present invention, when the suspended suspension is collected in the recovery device, the suspension is sprinkled or sprayed to create a flow toward the recovery device. The suspension can be efficiently recovered without providing a dynamic mechanical device such as a mechanism. Then, the treated water used for sprinkling or spraying is supplied from a tank provided at a position higher than the water level of the contact tank, and the transfer of the treated water to this tank makes it possible to pressurize the inside of the contact tank. In addition, since it is performed using the pressure when the water to be treated is pumped below the contact tank, it is not necessary to provide a device requiring a large power such as a liquid pump. As a result, the suspension can be efficiently recovered at a low cost.

  In addition, when the treated water is transferred to the high-position tank once stored in the low-position tank and then transferred from the low-position tank, the power for the transfer (power to pressurize the gas phase part) is used. The pressure at the time of pumping the water to be treated under the contact tank can be used, and even when a compressor is used, the equipment cost and operation cost can be reduced as compared with the case where water is pumped using a liquid pump. Therefore, it becomes possible to collect the suspension efficiently and at low cost.

  In addition, even when the suspension makes a flow toward the opening of the recovery device by the blower, the equipment cost and the operation cost can be reduced compared with the case of pumping using a liquid pump. Can be efficiently recovered at low cost.

It is a figure which shows the structure of the film processing apparatus which provided the liquid processing apparatus which concerns on 1st Embodiment. It is a cross-sectional view which shows the structure of the contact tank which inject | pours the ozone microbubble which concerns on 1st Embodiment, and is B-B 'sectional drawing of FIG.2 (b). It is a longitudinal cross-sectional view which shows the structure of the contact tank which inject | pours the ozone microbubble which concerns on 1st Embodiment, and is A-A 'sectional drawing of Fig.2 (a). It is a longitudinal cross-sectional view which shows the flow of the liquid phase in the contact tank with respect to discharge | emission of the suspension in a comparative example. It is a longitudinal cross-sectional view which shows the structure in a contact tank with respect to discharge | emission of the suspension material which concerns on 1st Embodiment, and the flow of a liquid phase. It is a longitudinal cross-sectional view which shows the structure which provided the means to measure the quantity of a suspension in the contact tank which concerns on 1st Embodiment. It is a longitudinal cross-sectional view which shows the structure which made the installation height of the collection | recovery device in the contact tank concerning 1st Embodiment low. It is a longitudinal cross-sectional view which shows the structure in the contact tank which concerns on 2nd Embodiment, and the flow of a liquid phase. It is a longitudinal cross-sectional view which shows the structure in the contact tank which concerns on 3rd Embodiment, and the flow of a liquid phase. It is a longitudinal cross-sectional view which shows the structure in the contact tank which concerns on 4th Embodiment, and the flow of a liquid phase. It is a figure which shows the structure of the film processing apparatus which provided the liquid processing apparatus which concerns on 5th Embodiment.

<< First Embodiment >>
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

  In the first embodiment, the present invention is applied to, for example, a sewage treatment apparatus that regenerates sewage or industrial effluent with ozone gas. In a bioreactor typified by a membrane separation activated sludge method (MBR), The present invention relates to a membrane treatment facility that treats industrial wastewater and generates high-quality recycled water using a reverse osmosis (RO) membrane.

  In the present embodiment, the water to be treated is concentrated water (RO concentrated water) containing the material to be separated removed by the RO membrane treatment. The bubbles generated in the water to be treated are ozone microvalves. That is, ozone is used as a source gas (original gas) that generates bubbles. Also, ozone microbubbles are generated using the residual pressure of the RO concentrated water. The substance to be separated in the concentrated water and the excess sludge supplied from the MBR to the contact tank are oxidatively decomposed by the ozone microvalve, and the suspension remaining after the oxidative decomposition is floated and separated. The RO concentrated water is pumped to the contact tank using the residual pressure by the RO membrane treatment.

  The basic configuration of this embodiment is a biological reaction tank, a pump that pressurizes the treated water in the biological reaction tank and feeds it to the RO membrane treatment apparatus, and an RO membrane treatment in which treated water filtered by the RO membrane treatment apparatus is distributed. Introducing a water channel, a concentrated water channel for draining concentrated water containing the substance to be separated removed by the RO membrane treatment, a gas mixer for mixing ozone gas into the concentrated water channel, and introducing concentrated water mixed with ozone gas A dissolved water tank for dissolving ozone in concentrated water, a nozzle for generating ozone microbubbles by foaming the concentrated water discharged from the dissolved water tank under reduced pressure, and a structure capable of forming an airtight state and communicating with the nozzle below the operating water level A contact tank to which concentrated water containing ozone microbubbles is supplied, a collector for collecting suspension suspended by microbubbles accompanying the concentrated water supplied in the contact tank, and a suspension from the collector Eliminate Discharge channel, on-off valve A provided in the discharge channel, water distribution channel for distributing treated water from the contact tank, on-off valve B provided in the water distribution channel, and higher than the liquid level of the contact tank The liquid header and the cleaning water tank are communicated with each other through the opening / closing valve C, the cleaning liquid tank provided in the location, the liquid header (watering device) having a sprinkling port installed above the collector opening in the contact tank. A cleaning liquid channel, a pumping channel that communicates the upstream portion of the water distribution channel with the opening / closing valve B and the cleaning water tank, an exhaust gas treatment device, a gas phase portion in the contact tank and the exhaust gas treatment device via the opening / closing valve D. An exhaust gas processing flow path that communicates with a control device that controls opening and closing of the on-off valves A to D is provided.

  The processing method of this embodiment has two operation modes, a normal operation mode and a suspension removal mode. In the normal operation mode, the on-off valve A and the on-off valve C are closed, and the on-off valve B and the on-off valve D are closed. In the suspension removal mode, the ozone microbubbles generated by the microbubble generator are reacted with the concentrated water supplied in the contact tank, and the suspension is adsorbed and floated and separated on the surface of the contact tank. In the first step, the on-off valve B and the on-off valve D are closed to close the flow path communicating with the contact tank except for the pumping flow path, and the treated water is supplied to the cleaning liquid tank using the pressure of the concentrated water pumped to the contact tank. Part of the water is pumped and stored. In the second step, on-off valve A and on-off valve D are opened, the water level is raised by the flow of concentrated water into the contact tank, and the suspended suspension is contacted from the collector opening. Drain out of the tank and open the on-off valve C to open the wash water tank. Wash water is supplied to the liquid header, sprinkled on the contact tank wall from the liquid header, induces a flow from the contact tank wall to the collector opening in the suspended suspension, and the suspension collects the suspension in the collector. The on-off valve B is opened after the collected and discharged from the discharge passage and the suspended suspension is discharged, and the on-off valve A and the on-off valve C are closed to return to the normal operation mode.

  Hereinafter, the configuration of the film processing facility of the present embodiment will be described in detail with reference to the drawings.

  The membrane treatment facility 100 is configured to treat sewage and industrial wastewater with MBR, and further generate high-quality reclaimed water with an RO membrane. Sewage or industrial wastewater, which is raw water, first flows into the sedimentation basin 25, and the supernatant liquid flows into the MBR biofilm reaction tank. The MBR treated water separated by the microfiltration membrane 33 provided in the biofilm reaction tank 34 is pressurized by the high pressure pump 2 and supplied to the RO membrane treatment apparatus 1 under pressure. The treated water that has permeated the RO membrane is distributed from the reclaimed water flow path 18 for use of the reclaimed water, and the concentrated water that does not permeate the RO membrane and is concentrated with substances to be separated such as organic substances is supplied from the RO membrane treatment apparatus 1 to the concentrated water flow. It is drained through the passage 11. The concentrated water flow path 11 is connected to a dissolved water tank 4 and a nozzle 6 having an ozone mixer 3 and an air vent 8 in order, and the downstream of the nozzle 6 communicates with the contact tank 5.

  Concentrated water flowing through the concentrated water flow path 11 is mixed with ozone gas generated by the ozone generator 7 in the ozone mixer 3. The ozone mixer 3 preferably uses a gas-liquid contact method utilizing the dynamic pressure of concentrated water such as an ejector. The ozone gas mixed with the concentrated water is dissolved in the concentrated water in the dissolved water tank 4 having the air vent 8. The concentrated water in which the ozone gas is dissolved is pressurized to a pressure corresponding to the pressure loss at the nozzle 6 and has high dissolution efficiency.

  The contact tank 5 is partitioned into upper and lower bypass structures by the partition plates 36a and 36b, has an airtight structure, and controls the opening and closing of the on-off valves provided in each flow path described later to control the gas phase in the contact tank. Prepare to apply pressure. Concentrated water containing microbubbles 29 generated at the nozzle 6 is injected into the contact tank 5. Further, the excess sludge extracted from the biofilm reaction tank 34 is in contact tank 5 water above the connection port of the nozzle 6 from the excess sludge flow path 31 provided with the excess sludge supply pump 30 and the opening / closing valve 35 (open / close valve G). To be supplied. Similarly, undissolved ozone gas separated by the air vent 8 is also supplied into the water in the contact tank 5 above the connection port of the nozzle 6. Excess sludge is oxidized by ozone microbubbles 29 in the concentrated water to be in a solubilized state that can be easily biologically treated, and the remaining solid components are suspended as suspensions 32 in the contact tank due to the floating separation effect of microbubbles 29. Float near the surface of the water. The treated water after the suspension 32 has been floated and separated is distributed from the distribution channel 9 as return water or discharge water in the biofilm reaction tank 34.

  In such a membrane treatment facility 100, in order to collect the suspended matter that has floated and separated in the space above the water surface of the contact tank 5, a recovery device 23 having an opening portion opened upward is provided. The collection device 23 and the outside of the contact tank 5 are communicated with each other by a discharge channel 13 that has an on-off valve 14 (on-off valve A) and discharges the suspended matter from the opening of the collection device 23. In addition, a liquid header 24 is provided to efficiently collect the suspension. The liquid header 24 is communicated with the lower part of the cleaning liquid tank 15 having an open structure provided higher than the liquid level of the contact tank 5 and the cleaning water flow path 17 having the on-off valve 16 (on-off valve C). Also. The water distribution channel 9 is provided with an on-off valve 10 (on-off valve B), and the upstream side of the on-off valve 10 of the water distribution channel 9 and the upper part of the washing water tank 15 are communicated with each other through a pumping channel 19. Undissolved ozone gas released into the upper space of the contact tank 5 passes through an exhaust gas recovery passage 22 having an open / close valve 21 (open / close valve D) as exhaust ozone, and is discharged by an exhaust gas treatment device 20 that performs an ozone decomposition catalyst or activated carbon treatment. Decomposed and released into the atmosphere. The exhaust gas treatment device 20 is necessary when ozone is used as a raw material gas for generating bubbles, but is necessary when the raw material gas is air or the like used in a liquid processing device whose main purpose is to perform floating separation. There is no.

  Next, with reference to FIG. 1 to FIG. 3B, the floating separation of the suspension and the action of collecting the suspension will be described. The suspension removal operation of the membrane treatment facility 100 is divided into a normal operation mode in which suspensions in concentrated water containing excess sludge are floated and a suspension removal mode in which suspensions floated and separated are removed from the contact tank 5. .

  In the normal operation mode, the on-off valve 14 and the on-off valve 16 are closed, and the on-off valve 10 and the on-off valve 21 are opened. That is, the floating separation of the suspension is performed with the contact tank 5 open to the atmosphere. Moreover, the on-off valve 35 is open, and surplus sludge in the biofilm reaction tank 34 is mixed with the concentrated water in the contact tank 5 by the surplus sludge supply pump 30. The concentrated water and excess sludge in the contact tank 5 are oxidized by the ozone gas microbubbles 29, and the organic matter in the concentrated water and excess sludge is decomposed. In particular, the solubilized treated water in which the organic matter of the COD component is decomposed and denatured into an organic component suitable for biological treatment is returned to the biofilm reaction tank 34 as return water, thereby making it possible to biologically treat the hardly degradable COD component. Become. Further, the suspension 32 derived from excess sludge floats and separates in the vicinity of the water surface of the contact tank 5 as shown in FIG.

  In the suspension removal mode, in addition to the on-off valve 14 and the on-off valve 16 as a first step, the on-off valve 10 and the on-off valve 21 are closed to communicate with the contact tank 5 except for the concentrated water channel 11 and the pumping channel 19. Close all the roads. As for the on-off valve 35, pressure is applied when surplus sludge is supplied to the contact tank 5, so that the open / close state is not limited. However, the surplus sludge supply pump 30 may be stopped to close the on-off valve 35 (that is, “ “Close all the channels communicating with the contact tank 5 except for the concentrated water channel 11 and the pumping channel 19” means that the contact tank and pressure (more precisely, a pressure higher than the head pressure in the pumped channel 19) is applied. Exclude those that are connected in the "close".) By opening and closing the valve, the gas phase in the contact tank 5 can be pressurized. In this state, the pressure of the gas phase in the contact tank 5 is increased by the dynamic pressure of the concentrated water injected from the nozzle 6, and the treated water passes from the water distribution channel 9 through the pumping channel 19 to the cleaning water tank as cleaning water. 15 is stored. The pressure in the contact tank 5 is higher than the atmospheric pressure because the head pressure in the pumping flow path 19 is applied. Although not shown, in this embodiment, a controller for controlling the operation of the pump and the opening / closing of each on-off valve is provided. The water level in the washing water tank 15 is measured by a sensor (not shown), and when the water level is full, each on-off valve is controlled to open and close as described later, and the operation is switched to the second step of the suspension removal mode. However, it is also possible to manually operate the pump and open / close the on-off valve.

  In the second step, the on-off valve 14, the on-off valve 21, and the on-off valve 16 are opened from the open / closed state of each valve in the first step. As a result, the pressure in the contact tank 5 is reduced to atmospheric pressure, and the water level in the contact tank 5 rises due to the concentrated water injected from the nozzle 6 and exceeds the outer periphery of the recovery device 23, so that the suspension from the recovery device 23 is suspended. Removal of concentrated water containing the turbid matter 32 out of the contact tank 5 starts. On the other hand, the washing water in the washing water tank 15 collides with the wall surface of the contact tank 5 and flows down from the water spout 43 opened in the liquid header 24 as shown in FIGS. A part of the wash water flowing down the wall surface flows from the wall surface of the contact tank 5 to the outer periphery of the suspension 32.

  In the conventional suspension removal by hopper (collector) and water level rise, as shown in FIG. 3A, the hydrodynamic driving force by which the suspension 32 is collected in the collector 23 is the suspension 32. Since there was only a shearing force accompanying the flow of concentrated water acting on the lower surface, a large amount of concentrated water would flow into the hopper before the suspension was collected in the hopper, and it would be long to remove the suspension 32. It took time. For this reason, a large amount of treated water and a long time are required to collect the total amount of the suspended matter, the water content of the suspended matter collected by the hopper is high, and the collected rate of treated water is also lowered.

  In this embodiment, as shown in FIG. 3B, since the flow of washing water from the wall surface of the contact tank 5 toward the suspension 32 is generated, the suspension is extruded by the washing water from the wall surface to the recovery device 23. 32 recovery is facilitated and the removal time of the suspension 32 is greatly reduced.

  As a result, the time for removing the suspension 32 from the collector 23 to the outside of the contact tank 5 is shortened, and the amount of water discharged from the collector 23 along with the suspension 32 is reduced. As a result, the water content of the recovered suspension 32 is reduced, and the power and power required for concentration, dehydration, and drying of excess sludge formed by the recovered suspension 32 can be reduced. Moreover, the reduction | decrease in the amount of water discharged accompanying the suspension 32 leads to the increase in the amount of the treated water distributed from a contact tank, and can increase the recovery rate of the treated water in the case of reclaiming treated water.

  After the removal of the suspended matter 32 from the collector 23 to the outside of the contact tank 5, the on-off valve 14 and the on-off valve 16 are closed and the on-off valve 10 is opened in order to return to the normal operation mode. When the on-off valve 35 is closed and the surplus sludge supply pump 30 is stopped in the first step of the suspension removal mode, the on-off valve 35 is opened and the surplus sludge supply pump 30 is started when returning to the normal operation mode.

  The duration of the normal operation mode and the activation interval of the suspension removal mode may be set using a timer by measuring the accumulated state of the suspension 32 in advance, and the thickness of the suspension 32 in real time. May be set to set a threshold value for activation determination. Further, the threshold value for the activation determination may be set by measuring the concentration of the suspension 32 in the treated water. The start / stop of the second step in the suspension removal mode may be performed by observing the removal state of the suspension 32 in advance and setting the duration using a timer. The amount of the suspension 32 on the water surface in real time. May be set to set a threshold value for determining start / stop.

  FIG. 4 shows an example in which a light source 45 and a light detection device 46 are used as means for measuring the amount of the suspension 32. A light source 45 that irradiates the water surface from the wall surface (ceiling surface) facing the gas phase space in the contact tank 5 is provided, and the light from the wall surface (ceiling surface) facing the gas phase space in the contact tank 5 toward the water surface is provided. The detection device 46 is provided, the reflection direction with respect to the irradiation of the light source 45 and the incident direction of the light detection device 46 are matched, and the reflectance of the surface of the suspension 32 is measured. In this method, it is possible to determine the removal of the suspension 32 by measuring in advance the reflectance of the water surface when the suspension 32 is not present in the contact tank 5. The suspension removal mode is activated by detecting the presence of the suspension on the contact tank water surface using the light detection device 46, and the suspension disappears using the light detection device 46 during the suspension removal mode operation. By confirming this, the suspension removal mode is shifted to the normal operation mode. As another suspension measurement method, the light detection device 46 may be directly opposed to the light source 45 and the transmittance may be measured, or an image may be taken and determined based on the brightness and color of the water surface. .

  FIG. 5 shows that the recovery unit 23 is installed at a height at which the outer periphery of the recovery unit 23 is submerged in the normal operation mode with respect to the arrangement of the contact tank 5 and the recovery unit 23 provided on the water surface of the liquid processing apparatus of FIG. This is an example. In this example, since the water level in the contact tank 5 can be lowered when the suspension 32 is removed, there is an effect that the height of the upper space of the contact tank 5 can be lowered.

  According to this embodiment, in the liquid processing apparatus that performs the oxidation treatment of the concentrated water, the solubilization treatment of the excess sludge, and the floating separation of the suspended matter by the ozone microbubbles generated using the residual pressure of the RO concentrated water. Since the suspension is made to flow toward the recovery device by sprinkling the treated water, the suspension can be recovered efficiently without providing a dynamic mechanical device such as a scum skimmer. . Further, treated water used for watering can be supplied from a washing water tank provided at a position higher than the water level of the contact tank, and the transfer of treated water to this washing water tank can pressurize the inside of the contact tank. Since it is performed using the pressure when the concentrated water is pumped to the contact tank in a state, it is not necessary to newly provide a device requiring a large power such as a liquid pump. As a result, without using an additional device or loop such as a liquid pump or scum skimmer, it is possible to accelerate the separation and removal of the suspension and reduce the water content of the separated and removed suspension. The processing cost required for concentration, dehydration and drying can be reduced. Moreover, since the recovery rate of treated water can be increased, when the treated water is recycled, the treatment cost unit price of the recycled water can be reduced. Due to the above effects, the economics of the membrane treatment facility can be improved.

<< Second Embodiment >>
The second embodiment will be described with reference to FIG. FIG. 6 shows another form of the contact tank 5 in the membrane treatment facility 100. The same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

  In this embodiment, the current plate 44 (44a, 44b) having a negative angle from the horizontal toward the wall surface is provided on the inner wall surface of the contact tank 5 below the outer peripheral height of the opening of the collector 23 of the contact tank 5. The rectifying plate 44 may be provided on the entire circumference of the inner wall surface of the contact tank 5 or may be provided for each location corresponding to the position of the water spout 43 shown in FIG.

  The washing water that collides with the wall surface of the contact tank 5 from the water spray port 43 of the liquid header 24 collides with the flow straightening plate 44, so that the flow direction of the flowing component along the wall surface is suspended from the wall surface of the contact tank 5. Facing the outer periphery of As a result, most of the washing water that collides with the wall surface and flows down as compared with the first embodiment is used to push the suspension 32 from the wall surface to the recovery device 23, so that the suspension 32 is recovered. Is further promoted and the removal time of the suspension 32 is greatly reduced.

  According to the present embodiment, basically the same effects as those of the first embodiment can be obtained. Moreover, in this embodiment, since the separation and removal performance of the suspension can be improved and the water content of the separated and separated suspension can be further reduced as compared with the first embodiment, the treatment required for the concentration, dehydration and drying of excess sludge Cost can be further reduced. Moreover, since the recovery rate of treated water can be increased, when the treated water is recycled, the cost of treating the recycled water can be further reduced. Due to the above effects, the economics of the membrane treatment facility can be improved.

<< Third Embodiment >>
A third embodiment will be described with reference to FIG. FIG. 7 shows another form of the contact tank 5 in the membrane treatment facility 100. The same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

  In this embodiment, instead of the liquid header 24 used in the first and second embodiments, an injection nozzle is installed on the wall surface in the vicinity of the height of the collector opening in the contact tank. That is, in the first and second embodiments, the wall surface is also cleaned by sprinkling water on the wall surface. However, in this embodiment, the wall surface is not particularly cleaned, and the suspension is directed to the collector by another means. It is designed to create a flow. Specifically, the washing water flow path 49 (49a, 49b) which has the on-off valve 48 (48a, 48b) (on-off valve H) is connected to the wall surface of the contact tank 5 and the partition plate 36b. The washing water channel 49 is provided in the vicinity of the outer peripheral height of the recovery device 23, and the spray nozzle 47 (47 a, 47 b) faces the recovery device 23. The injection nozzle 47 is preferably shaped so that the tip can be squeezed and the washing water can be injected onto the suspension 32 in a horizontal plane (for example, a flat shape that expands into a fan shape). The washing water channel 49 is connected to the washing water tank 15 in FIG. Moreover, the injection nozzle 47 has the same arrangement as the water spout 43 shown in FIG.

  In the second step of the suspension removal mode, the on-off valve 14, the on-off valve 21, and the on-off valve 48 are opened from the open / close state of each valve in the first step. While the pressure in the contact tank 5 decreases to atmospheric pressure, the water level in the contact tank 5 rises by the concentrated water injected from the nozzle 6 and exceeds the outer periphery of the recovery device 23, and the suspended matter 32 from the recovery device 23. The removal of the concentrated water containing the liquid starts outside the contact tank 5. At the same time, the washing water is jetted from the washing water flow path 49 toward the collecting device 23, a flow toward the collecting device 3 is formed by the dynamic pressure of the washing water, and the suspension 32 is formed in the opening of the collecting device 23. Extruded.

  According to the present embodiment, basically the same effects as those of the first embodiment can be obtained. In the present embodiment, the suspension separation and removal process can be promoted only by connecting the pipes without providing a liquid header in the contact tank in the first embodiment. As a result, it is possible to reduce the facility cost as well as the operating cost of the membrane treatment facility and improve the economy.

<< Fourth Embodiment >>
A fourth embodiment will be described with reference to FIGS. 1 and 8. FIG. 8 shows another form of the contact tank 5 in the membrane treatment facility 100. In FIG. 8, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

  This embodiment was installed on the wall surface in the vicinity of the height of the collector opening in the contact tank, instead of spraying or jetting cleaning water using the liquid header or cleaning water flow path used in the first to third embodiments. A gas nozzle, a blower provided outside the contact tank, and a gas flow path communicating the gas nozzle and the blower are provided. Although the washing water tank 16 or the like is not provided, it may be provided mainly for washing the inner wall surface of the contact tank 5.

  As shown in FIG. 8, gas nozzles 51 (51 a, 51 b) connected to the blower 50 (50 a, 50 b) are provided on the wall surface of the contact tank 5 and the partition plate 36 b above the outer peripheral height of the opening of the recovery unit 23. Is directed to the recovery device 23. The injection port is preferably shaped so that the tip can be squeezed and air can be injected from the outer periphery of the suspension 32 to the collector 23 at a negative angle from the horizontal. Moreover, the gas nozzle 51 has the same arrangement as the water spout 43 shown in FIG. The number of arrangement may be smaller or larger than that of the water spout 43.

  The normal operation mode is basically the same as that in the first embodiment. The suspension removal mode is only a step corresponding to the second step in the first embodiment, and there is no one corresponding to the first step. That is, the open / close valve 14 is opened and the open / close valve 10 is closed when the suspended matter is removed. As a result, the pressure in the contact tank 5 is reduced to atmospheric pressure, and the water level in the contact tank 5 rises due to the concentrated water injected from the nozzle 6 and exceeds the outer periphery of the recovery device 23, so that the suspension from the recovery device 23 is suspended. Removal of concentrated water containing the turbid matter 32 out of the contact tank 5 starts. On the other hand, the blower 50 is started and air is sprayed onto the upper surface of the suspension 32 from the vicinity of the wall surface of the contact tank 5 and the partition plate 36b. In addition to the shearing force associated with the flow of concentrated water acting on the lower surface of the suspension 32, the shearing force generated on the surface of the suspension 32 by the injected air causes the suspension 32 to open from the upper and lower surfaces of the suspension 32. The suspension 32 gets over the outer periphery of the collector 23 and is removed from the discharge channel 13 to the outside of the contact tank 5. In this embodiment as well, as in the first embodiment, a controller may be provided to control the operation of the pump and blower and the opening / closing of each on-off valve, or the operation and opening / closing of the pump and blower manually. You may make it open and close a valve.

  According to the present embodiment, basically the same effects as those of the first embodiment can be obtained. In the present embodiment, since air is used for promoting recovery of the suspension 32 and shortening the removal time, the suspension removal mode first in which the treated water is pumped to the washing tank 15 in the first to third embodiments. The process and the cleaning tank 15 are unnecessary. Moreover, although the installation cost of the air blower 50 and its operation cost are applied, since the density of air is small compared with water, the equipment cost and operation cost of an air blower are small with respect to pumping of wash water. That is, the suspension can be efficiently removed at low cost.

<< Fifth Embodiment >>
A fifth embodiment will be described with reference to FIG. The same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate. The membrane treatment facility 101 of the present embodiment is basically the same as that of the first embodiment, and is provided with a treated water tank 37 having an airtight structure below the water distribution channel 9 and is in contact via the treated water tank 37. It is characterized in that the treated water is transferred to the wash water tank 15 having an open structure provided at a higher position than the liquid level of the tank 5.

  The treated water tank 37 communicates with the water distribution channel 9 through a water extraction channel 38. The extraction flow path 38 branches from the water distribution flow path 9 downstream from the open / close valve 10 on the water distribution flow path 9 and has an open / close valve 39 (open / close valve F). The lower part of the treated water tank 37 and the washing water tank 15 are communicated with each other through the second pumping flow path 40. The upstream side of the on-off valve 21 of the exhaust gas recovery passage 22 communicates with the treated water tank 37 through a pressurizing passage 41 having an on-off valve 42 (on-off valve E). The gas phase part in the contact tank 5 and the gas phase part of the treated water tank 37 are communicated with each other by the pressurized flow path 41. In addition, a compressed flow path 54 that supplies compressed air from the compressor 52 is connected to the treated water tank 37 via an open / close valve 53 (open / close valve J).

  The action of collecting the suspension will be described with reference to FIG. As in the first embodiment, the suspension removal operation of the membrane treatment facility 101 is performed in the normal operation mode in which the suspension in the concentrated water containing the excess sludge is floated and in the contact tank 5. And a suspension removal mode for removing from the suspension. Similarly, the suspension removal mode is divided into a first step in which washing water is pumped into the washing water tank 15 and a second step in which the suspension 32 is collected and removed by the collector 23.

  The normal operation mode is basically the same as that in the first embodiment. In the present embodiment, the on-off valve 39 is further opened. Accordingly, part of the treated water that has flowed through the water distribution channel 9 flows down to the treated water tank 37 through the extraction channel 38 and is stored. Although not shown, preferably the water level of the treated water tank 37 is measured by a controller that measures the water level and controls the operation and opening / closing of the pumps and valves. Is closed and the operation is switched to the first step of the suspension removal mode.

  In the first step of the suspension removal mode, in the same manner as in the first embodiment, in addition to the on-off valve 14 and on-off valve 16, the on-off valve 10 and on-off valve 21 are closed and the on-off valve 42 is opened. About the on-off valve 35, since a pressure is applied when surplus sludge is supplied to the contact tank 5, similarly to 1st Embodiment, an open / close state is not ask | required. The surplus sludge supply pump 30 may be stopped and the on-off valve 35 may be closed. By opening and closing the valve, the water level in the contact tank 5 is raised by the concentrated water injected together with the microbubbles 29 from the nozzle 6, and the upper space of the contact tank 5 is pressurized. The pressurized gas in the upper space passes through the pressurized flow path 41 and flows into the treated water tank 37, and the inside of the treated water tank 37 is pressurized. As a result, the treated water in the treated water tank 37 flows into the wash water tank 15 having an open structure through the second pumping flow path 40 and is stored therein. The water level of the treated water tank 37 is measured, and when the treated water tank 37 becomes empty, the operation is switched to the second step in the suspension removal mode. When the flush water pressure is increased by installing the flush water tank 15 at a higher location, the open / close valve 42 is closed, the open / close valve 53 is opened, and the compressor 52 is operated to increase the pressure in the treated water tank 37. May be.

  In the second step, as in the first embodiment, the on-off valve 14, the on-off valve 21, and the on-off valve 16 are opened from the open / close state of each valve in the first step. When the washing water tank 15 is installed at a high place, the on-off valve 53 is closed and the operation of the compressor 52 is stopped. As a result, the pressure in the contact tank 5 is reduced to atmospheric pressure, and the water level in the contact tank 5 exceeds the outer periphery of the recovery device 23 by the concentrated water injected from the nozzle 6, and the suspended matter 32 from the recovery device 23. The removal of the concentrated water containing the liquid starts outside the contact tank 5. On the other hand, the wash water in the wash water tank 15 collides with the wall surface of the contact tank 5 and flows down from the water spout 43 opened in the liquid header 24 as shown in FIG. 2 as in the first embodiment. A part of the wash water flowing down the wall surface flows from the wall surface of the contact tank 5 to the outer periphery of the suspension 32. In addition, it may replace with a liquid header and may use the injection nozzle 47 of 3rd Embodiment shown in FIG.

  Also in this embodiment, as shown in FIG. 3B, the flow of washing water from the wall surface of the contact tank 5 toward the suspension 32 and the recovery device 23 is generated, so that the cleaning water flows from the wall surface to the recovery device 23. Extrusion facilitates the recovery of the suspension 32 and the removal time of the suspension 32 is greatly shortened. Further, in the case where the cleaning water tank 15 is installed at a higher location and the sprinkling pressure of the cleaning water is increased, the structure needs to be strengthened in order to increase the pressure resistance of the contact tank 5, but in this embodiment, only the treated water tank 37 is used. Should be strengthened. Moreover, although the installation cost of the compressor 52 and its operation cost are applied, the operation cost in this embodiment is low compared with the case where the washing water is pumped using a pump. That is, the suspension can be efficiently removed at low cost.

  As a result, the time for removing the suspension 32 from the collector 23 to the outside of the contact tank 5 is shortened, and the amount of water discharged from the collector 23 along with the suspension 32 is reduced. As a result, the water content of the recovered suspension 32 is reduced, and the power and power required for concentration, dehydration, and drying of excess sludge formed by the recovered suspension 32 can be reduced. Moreover, the reduction | decrease in the amount of water discharged accompanying the suspension 32 leads to the increase in the amount of the treated water distributed from a contact tank, and can increase the recovery rate of the treated water in the case of reclaiming treated water.

  After the removal of the suspended matter 32 from the collector 23 to the outside of the contact tank 5, the on-off valve 14, the on-off valve 16 and the on-off valve 42 are closed and the on-off valve 10 is opened in order to return to the normal operation mode. When the on-off valve 35 is closed and the surplus sludge supply pump 30 is stopped in the first step of the suspension removal mode, the on-off valve 35 is opened and the surplus sludge supply pump 30 is started when returning to the normal operation mode. Further, the on-off valve 39 is opened, and water storage into the treated water tank 37 is started.

  According to the present embodiment, in addition to the effects of the first embodiment, the watering pressure can be increased without strengthening the structure of the contact tank, so that there is an effect that the separation and removal of the suspended matter can be further promoted.

  In this embodiment, the water is once stored in the treated water tank and transferred to the washing water tank installed at a high place. However, if the position of the treated water tank is provided near the water surface of the contact tank, the treated water Since the pump power for supplying the liquid to the liquid header can be small, it is conceivable to omit the washing water tank and supply the treated water directly from the treated water tank to the liquid header using a pump.

  In each of the above-described embodiments, the liquid treatment apparatus is described in which the present invention is applied to a sewage membrane treatment facility that combines MBR and RO membrane filtration and treats RO concentrated water with an ozone microvalve. However, the present invention is not limited to this. Is not to be done. For example, in a liquid processing apparatus that supplies pressurized water in which air is dissolved under high pressure to the lower part of the contact tank together with the water to be treated, and attaches suspended substances contained in the water to be treated to bubbles generated from the pressurized water and floats and separates them. Is also applicable.

1 RO membrane treatment equipment 2 High-pressure pump (pump)
3 Ozone mixer (gas mixer)
4 Dissolving water tank 5 Contact tank 6 Nozzle 7 Ozone generator 8 Air vent 9 Water distribution flow path 10 Open / close valve (open / close valve B)
11 Concentrated water channel 12 Gas phase channel 13 Discharge channel 14 On-off valve (on-off valve A)
15 Washing water tank 16 On-off valve (on-off valve C)
17 Washing water flow path 18 Reclaimed water flow path 19 Pumping water flow path 20 Exhaust gas treatment device 21 Open / close valve (open / close valve D)
22 Exhaust gas treatment channel 23 Recovery device 24 Liquid header 25 First sedimentation basin 29 Micro bubble 30 Excess sludge supply pump 31 Excess sludge channel 32 Suspension 33 Microfiltration membrane 34 Biofilm reaction tank 35 On-off valve (on-off valve G)
36 Partition plate 37 Treated water tank 38 Extraction flow path 39 Open / close valve (open / close valve F)
40 Second pumping channel 41 Pressurizing channel 42 On-off valve (on-off valve E)
43 Water spout 44 Current plate 45 Light source 46 Photodetector 47 Injection nozzle 48 On-off valve (on-off valve H)
49 Washing water flow path 50 Blower 51 Gas nozzle 52 Compressor 53 On-off valve (On-off valve J)
54 Compression channel 100 Membrane treatment equipment 101 Membrane treatment equipment

Claims (17)

A contact tank that floats and separates a suspension from the water to be treated by bringing bubbles into contact with the water to be treated, and a collector that collects the suspended suspension that is disposed in the contact tank with an opening opened upward. The water to be treated containing air bubbles is pumped from below the water level of the contact tank to the contact tank, and the suspension is recovered by raising the water level of the contact tank when the suspension is recovered. In the liquid processing apparatus adapted to collect the gas in the recovery device,
The contact tank has an airtight structure, and is branched from a tank provided at a position higher than the water surface of the contact tank, and a water distribution channel for removing the treated water from which the suspension is floated and separated from the contact tank, and is processed into the tank. A pumping flow path for transferring water, and a sprinkler or spray nozzle in which treated water from the tank is sprinkled or sprayed into the contact tank so that the suspension flows toward the opening of the collector. And
By blocking the communication between the inside of the contact tank and the outside except the flow path for supplying the treated water to the contact tank and the pumping flow path, and supplying the treated water into the contact tank, A liquid processing apparatus, wherein the inside of the contact tank is pressurized so that the treated water is transferred to the tank through the pumping flow path. In Claim 1, The treated water tank provided below the distribution channel, The extraction channel which branches off from the distribution channel, and extracts a part of the treated water to the treated water tank, The contact tank A pressurized flow path that communicates the gas phase section and the treated water tank; instead of the pumped flow path, the treated water is transferred from the treated water tank to a tank provided at a position higher than the water surface of the contact tank. A pumping channel for transporting
Except for the flow path for supplying the treated water to the contact tank and the pressurized flow path, the communication between the inside and outside of the contact tank is blocked, and the treated water except for the pressurized flow path and the pumping flow path is used. By blocking communication between the inside of the tank and the outside, and supplying the water to be treated into the contact tank, the inside of the contact tank is pressurized to further pressurize the inside of the treated water tank, and the treated water is A liquid processing apparatus, wherein the liquid is transferred from a treated water tank to a tank provided at a position higher than the water surface of the contact tank through the pumping flow path. A contact tank that floats and separates a suspension from the water to be treated by bringing bubbles into contact with the water to be treated, and a collector that collects the suspended suspension that is disposed in the contact tank with an opening opened upward. The water to be treated containing air bubbles is pumped from below the water level of the contact tank to the contact tank, and the suspension is recovered by raising the water level of the contact tank when the suspension is recovered. In the liquid processing apparatus adapted to collect the gas in the recovery device,
A liquid processing apparatus comprising: a gas nozzle that injects a gas that gives an air flow toward the opening of the recovery unit into the contact tank; and a blower that supplies the gas to the gas nozzle.   A contact tank having an airtight structure, a supply means for pumping water to be treated below the water level of the contact tank, a microbubble generator for generating microbubbles of raw material gas in the water to be treated to be pumped by the supply means, An opening that opens upward in the contact tank is disposed, and a collector that collects suspension suspended by microbubbles accompanying the water to be treated supplied to the contact tank, and a suspension from the collector A discharge flow path for discharging an object, an opening / closing valve A provided in the discharge flow path, a water distribution flow path for distributing treated water from the contact tank, an open / close valve B provided in the water distribution flow path, A washing water tank provided above the water surface of the contact tank and a water spout installed above the opening of the recovery device, and the suspension is directed to the recovery device by watering from the water spout. A liquid that is induced to flow A wash water flow path for communicating the liquid header and the wash water tank, an open / close valve C provided in the wash water flow path, the water distribution flow path upstream of the open / close valve B, and the wash water tank. A liquid processing apparatus, comprising: a pumping flow channel that communicates, a gas flow channel that communicates a gas phase portion in the contact tank and the outside, and an on-off valve D provided in the gas flow channel.   A contact tank having an airtight structure, a supply means for pumping water to be treated below the water level of the contact tank, a microbubble generator for generating microbubbles of raw material gas in the water to be treated to be pumped by the supply means, An opening that opens upward in the contact tank is disposed, and a collector that collects suspension suspended by microbubbles accompanying the water to be treated supplied to the contact tank, and a suspension from the collector A discharge flow path for discharging an object, an opening / closing valve A provided in the discharge flow path, a water distribution flow path for distributing treated water from the contact tank, an open / close valve B provided in the water distribution flow path, A wash water tank provided above the water surface of the contact tank, a treated water tank provided below the water distribution channel, and a water extraction tank communicating the water distribution channel downstream of the on-off valve B and the treated water tank. Provided in the water channel and the extraction channel. The open / close valve F, a pumping flow path that communicates the treated water tank and the washing water tank, a pressurized flow path that communicates the gas phase portion in the contact tank and the gas phase portion of the treated water tank, There is an on-off valve E provided in the pressure channel, and a water spout installed above the opening of the recovery unit, and the flow of the suspension toward the recovery unit is induced by the water spray from the water spout. The liquid header configured as described above, the cleaning water flow path communicating with the liquid header and the cleaning water tank, the on-off valve C provided in the cleaning water flow path, and the gas phase portion in the contact tank and the outside communicate with each other. A liquid processing apparatus comprising a gas flow path and an on-off valve D provided in the gas flow path.   6. The liquid treatment apparatus according to claim 4, wherein an exhaust gas treatment device is provided in the gas flow path, and the inside of the contact tank and the exhaust gas treatment device are communicated with each other via the on-off valve D. apparatus.   6. The liquid processing apparatus according to claim 4, further comprising a control device that controls opening and closing of each of the on-off valves.   6. The liquid processing apparatus according to claim 4, wherein a rectifying plate having a negative angle from the horizontal is provided on a wall surface of the contact tank below the opening height of the recovery unit. .   6. The liquid processing apparatus according to claim 4, wherein, instead of the liquid header, the treated water is injected into the contact tank so that the suspension forms a flow toward the opening of the collector. The spray nozzle is installed on a wall surface near the opening height of the recovery device in the contact tank, and communicates with the wash water flow path via the on-off valve C. Liquid processing equipment.   6. The liquid processing apparatus according to claim 4, wherein a light source for irradiating light on a water surface in the contact tank and a light detection device for detecting reflected light from the water surface face a gas phase space of the contact tank. A liquid processing apparatus provided on a wall surface, wherein the presence of a suspended substance on the water surface of the contact tank is detected by the reflected light.   6. The liquid processing apparatus according to claim 4, wherein a light source provided in the water in the contact tank and a light detection provided on a wall surface facing the gas phase space of the contact tank to detect transmitted light from the light source. A liquid processing apparatus having an apparatus, wherein the presence of a suspension on the water surface of the contact tank is detected by the transmitted light.   6. The liquid processing apparatus according to claim 4 or 5, wherein a photographing device for photographing the water surface of the contact tank is provided, and the presence of a suspension of the contact tank water surface is detected by a photographed image photographed by the photographing device. A liquid processing apparatus characterized by comprising: A liquid processing method using the liquid processing apparatus according to claim 4,
It has a normal operation mode and a suspension removal mode,
In the normal operation mode, the on-off valve A and the on-off valve C are closed, the on-off valve B and the on-off valve D are opened, and the microbubbles are reacted with the water to be treated in the contact tank and suspended. Adsorbs and floats to the surface of the water to be treated,
The suspension removal mode has a first step and a second step, and in the first step, the on-off valve B and the on-off valve D are closed to communicate with the contact tank other than the pumping water passage. In the second step, the on-off valve A and the on-off valve D are opened to open the water to be treated. The suspension that floats and separates by raising the water level in the contact tank by flowing into the contact tank is discharged from the opening of the recovery device to the outside of the contact tank, and the on-off valve C is opened to open the liquid header. Watering from
A liquid processing method comprising: opening the on-off valve B after discharging the suspended and separated suspension, closing the on-off valve A and the on-off valve C, and returning to the normal operation mode. A liquid processing method using the liquid processing apparatus according to claim 5,
It has a normal operation mode and a suspension removal mode,
In the normal operation mode, the on-off valve A and the on-off valve C are closed, and the on-off valve B, the on-off valve D, and the on-off valve F are opened, and the treated water in the contact tank Reacts with microbubbles, adsorbs suspended matter, floats and separates on the surface of the water to be treated, and stores part of the treated water flowing through the water distribution channel in the treated water tank through the extraction channel, completing the water storage Later, the on-off valve F is closed,
In the suspension removal mode, in the first step, the on-off valve B and the on-off valve D are closed, the flow path communicating with the contact tank excluding the pressurized flow path is closed, and the contact tank is controlled by the pressure of the water to be treated. The gas in the upper space is pressurized and supplied to the treated water tank through the pressurized flow path, whereby the water in the treated water tank is pumped and stored in the washing water tank, and the opening and closing is performed in the second step. Open the valve A and the on-off valve D to raise the water level of the contact tank by inflow into the contact tank of the treated water and float the separated suspension from the opening of the collector to the outside of the contact tank. And discharging the on-off valve C to sprinkle water from the liquid header,
A liquid processing method comprising: opening the on-off valve B and the on-off valve F after discharging the suspended suspension, closing the on-off valve A and the on-off valve C, and returning to the normal operation mode. The liquid processing apparatus according to claim 6.
The liquid treatment apparatus is a sewage treatment facility having a biological reaction tank and a reverse osmosis membrane treatment apparatus for treating treated water in the biological reaction tank,
The treated water is concentrated water containing a substance to be separated removed by the reverse osmosis membrane treatment apparatus, and has a concentrated water flow path that communicates the reverse osmosis membrane treatment apparatus and the contact tank,
As a drive source of the supply means, using a pump that pressurizes the treated water in the biological reaction tank and feeds it to the reverse osmosis membrane treatment apparatus,
The micro-bubble generating device is provided in the concentrated water flow path, a gas mixer that mixes ozone gas that is the raw material gas, a dissolved water tank that introduces concentrated water mixed with the ozone gas and dissolves ozone in the concentrated water, And a nozzle for generating ozone microbubbles by foaming the concentrated water from the dissolved water tank under reduced pressure, and the nozzle is connected below the operating water level of the contact tank. . The liquid processing apparatus according to claim 15, wherein
A liquid treatment apparatus comprising a surplus sludge injection channel for supplying surplus sludge extracted from the biological reaction tank downward from an operating water level of the contact tank.   A contact tank having an airtight structure, a supply means for pumping water to be treated below the water level of the contact tank, a microbubble generator for generating microbubbles of raw material gas in the water to be treated to be pumped by the supply means, An opening that opens upward in the contact tank is disposed, and a collector that collects suspension suspended by microbubbles accompanying the water to be treated supplied to the contact tank, and a suspension from the collector A discharge flow path for discharging an object, an opening / closing valve A provided in the discharge flow path, a water distribution flow path for distributing treated water from the contact tank, an open / close valve B provided in the water distribution flow path, A treated water tank provided below the water distribution channel, a water distribution channel downstream from the on-off valve B, a bleed water channel communicating the treated water tank, and an on-off valve F provided in the bleed water channel; Installed above the opening of the collector A liquid header having a sprinkling port so that the flow of the suspension toward the recovery device is induced by watering from the sprinkling port, and a washing water flow path communicating the liquid header and the treated water tank; And a pump provided in the washing water flow path.

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