JP4018130B1 - Water treatment system - Google Patents

Abstract

[PROBLEMS] To provide a water treatment system capable of efficiently mixing gas-liquid in the entire system, even in liquids other than fresh water, such as slurry liquids, natural water bodies, waste water liquids, and the like, and increasing the dissolved oxygen concentration in the tank and the target water area. I will provide a.
A water treatment system S1 mixes a gas into a liquid via an ejector device 7 at a front side of a suction side 8A of a pump 8 that sucks, pressurizes and discharges the liquid in the tank, and mixes the gas and liquid with the mixer device. 9, the mixture is sent to the gas-liquid mixing device 10 </ b> A. The gas-liquid mixing device 10 </ b> C is arranged so that the tip of the fluid introduction tube 25 opens as a fluid introduction port 28 close to the inner bottom surface of the sealed container 24. By providing, the gas-liquid introduced into the sealed container through the fluid inlet port diffuses in a thin layer in a fan shape to the left and right along the inner surface of the sealed container, forming a high-speed vortex in the sealed container. As a result, the gas-liquid is efficiently mixed and the dissolved oxygen concentration in the liquid is increased.
[Selection] Figure 5

Description

  The present invention relates to a water treatment system that mixes a gas such as air and a liquid to increase the dissolved oxygen concentration in the tank, and in particular, a liquid other than fresh water, such as slurry liquid, natural water, waste water liquid, etc. The gas-liquid can be mixed efficiently and the dissolved oxygen concentration in the tank can be increased.

  Conventionally, as this type of water treatment system, for example, a system in which gas and liquid are mixed by sucking gas and liquid into an eddy current pump is known (for example, see Patent Documents 1 and 2). However, according to this method, at least the impeller and its rotation support mechanism are required to break and stir the gas in the gas and liquid by narrowing the gap between the rotating impeller and the container that accommodates it as much as possible. Is complicated, and power for rotating the impeller is also necessary. Furthermore, in this method, the mixture in the liquid is sandwiched in the extremely narrow gap as described above, and the impeller is locked and cannot rotate, or the impeller and its rotation support mechanism are worn by the mixture. For this reason, the liquid to be treated for gas-liquid mixing is mainly limited to fresh water without inclusions, and cannot be employed as a water treatment system for treating liquids such as slurry liquids, natural water bodies, and wastewater.

  Patent Document 1 discloses a method for directly feeding gas to the suction side of a vortex pump as this type of water treatment system. However, instead of the vortex pump, for example, when a non-volumetric type centrifugal pump (vortex pump) that is most commonly used at present is used, a centrifugal pump in which a large amount of gas is sucked into the centrifugal pump A specific problem occurs, that is, idling of the pump, reduction of the discharge amount, and the like. For this reason, the problem that the mixing efficiency of the gas-liquid as the whole system falls arises.

  In Patent Document 3, as this type of water treatment system, a gas-liquid introduction hole (22a) is formed in the peripheral wall of an elliptical spherical body (21), and the container (from the gas-liquid introduction hole (22a) ( 21) A method is described in which air / water is mixed in the container (21) by introducing the air / fuel mixture into the body (21) (see paragraph 0017 of the document 3). However, according to this method, the formation of the turbulent vortex of the mixed water introduced into the vessel (21) is different from the formation of the high-speed flow by thin layer diffusion as in the present invention.

  In addition, this type of water treatment system includes a method in which pressure fluid is released from a small hole and rapidly decompressed and ejected, a method in which pressure fluid is ejected from a nozzle toward a wall and collided with the wall, and a fluid from an opposing nozzle There is also known a method in which fluids are caused to collide with each other by jetting the fluid. However, when liquids such as slurry liquid, natural water, and wastewater are processed by these methods, the mixed substances in the liquid are clogged in small holes and nozzles. It is limited and cannot be employed as a water treatment system for treating liquids such as slurry liquids, natural water bodies and wastewater.

JP 2000-161278 A

JP 2002-273183 A

JP 2003-102324 A

  The present invention has been made to solve the above-described problems, and the object of the present invention is mainly slurry liquid, natural water (land water, sea water, brackish water), artificial water (reservoirs such as dams, Aquatic animals breeding / aquaculture areas, baths, etc.), household miscellaneous wastewater, liquids other than fresh water, such as liquids from factory wastewater, to efficiently mix gas-liquid throughout the system and increase the dissolved oxygen concentration in the tank and the target water area It is to provide a water treatment system that makes it possible.

In order to achieve the above object, a water treatment system according to a first aspect of the present invention includes a pump that sucks and pressurizes liquid in a tank, and an ejector that mixes gas in the liquid at a stage upstream of the suction side of the pump. An apparatus, a mixer device for stirring the gas and liquid discharged from the pump, and the gas and liquid stirred by the mixer device are mixed by vortex and decompressed and discharged into the tank. A water treatment system comprising a gas-liquid mixing device, wherein the gas-liquid mixing device includes a cylindrical sealed container, a fluid introduction pipe for introducing gas-liquid into the sealed container, and a gas from the sealed container. A fluid discharge port for discharging liquid, and in a state in which the cylindrical sealed container is placed sideways, the fluid introduction pipe penetrates the side surface of the cylindrical sealed container and enters the sealed container. This got in Tip body inlet tube, a fluid inlet, and being provided so as to open and close to the inner bottom surface of the hermetic container of the cylindrical shape.

  In the water treatment system according to the first aspect of the present invention, gas-liquid pressurization, stirring, and mixing are performed in three stages of a pump, a mixer device, and a gas-liquid mixing device. In addition, the gas-liquid mixing device employed in this water treatment system is such that the gas-liquid introduced into the sealed container through the fluid inlet port is diffused into a fan-like layer from side to side along the inner surface of the sealed container. A high-speed vortex is formed in the container, and gas and liquid are efficiently mixed by this high-speed vortex.

  In the water treatment system according to the first aspect of the present invention, the fluid discharge port may have a nozzle structure having a suction hole provided in the center thereof and a plurality of ejection holes provided around the suction hole. .

  According to the nozzle structure, a drawing vortex with a gas column extending from the inside of the sealed container through the central suction hole is formed, and the gas outside the sealed container can easily enter the sealed container through the gas column. Gas-liquid in the sealed container can be easily discharged from the surrounding ejection holes, and the gas-liquid discharge efficiency is improved. In addition, the gas-liquid discharge and suction operations performed through the suction holes and the jet holes cause complex turbulent flow near these holes, and this turbulence further promotes the mixing of gas and liquid. In addition, an effect that the amount of dissolved oxygen in the liquid can be increased is also obtained.

  In the nozzle structure described above, the diameters of the suction holes and the ejection holes are relatively large, and the mixed substances in the liquid are not clogged in these holes. However, among the mixed substances other than water existing in the liquid such as natural waters and wastewater, large foreign matters mixed in fallen leaves and other wastewater should be at least put on a commercially available wire net before introduction into the gas-liquid mixing device. It is desirable to remove it. For example, sand grains passing through a commercially available wire mesh can easily pass through suction holes and ejection holes as long as the diameter is about 5 mm or less, and can be efficiently used as described above by using suction holes and ejection holes having relatively large diameters. It is advisable to discharge gas and liquid.

  In the nozzle structure described above, the diameter of the central suction hole may be larger than the diameter of the ejection hole formed in the periphery thereof. If comprised in this way, even if it sucks in the mixture discharged | emitted from the ejection hole when a suction hole inhales a part of gas-liquid discharged | emitted from the ejection hole, clogging of a suction hole will not arise.

  Moreover, in the structure which employ | adopted the said nozzle structure, you may employ | adopt the structure by which a discharge cylinder is attached to the fluid discharge side of the said fluid discharge port further.

  According to the configuration with the discharge cylinder as described above, the gas and liquid discharged from the ejection holes are sucked from the suction holes, and the vicinity of the outlet of the discharge cylinder is occupied by the gas and liquid discharged from the ejection holes. Therefore, the effect that the suction holes are not clogged is obtained. If this discharge cylinder is excluded, there is a possibility that liquid other than gas and liquid discharged from the ejection hole may be sucked into the suction hole, and there is a possibility that a large liquid mixture may clog the suction hole. Thus, it is preferable to attach a discharge cylinder to the fluid discharge side of the fluid discharge port.

  Furthermore, in the structure which employ | adopted the said discharge cylinder, you may employ | adopt the structure further provided with the gas introduction pipe | tube connected from the outer side of the said discharge cylinder to the fluid discharge side negative pressure part of the said fluid discharge port.

  According to the configuration including the gas introduction pipe as described above, in the vicinity of the inlet / outlet of the fluid discharge port, the gas suction and the suction operation performed through the suction hole and the ejection hole are further performed, and the gas suction through the gas introduction pipe is performed. When the operation is added, a more complicated turbulent flow is generated, gas-liquid mixing is further promoted, and the amount of dissolved oxygen in the fluid can be further increased.

  In order to achieve the above object, a water treatment system according to the second aspect of the present invention includes a pump that sucks and pressurizes a liquid in a tank and discharges the liquid in the liquid at a discharge side diverting part or a front stage of the suction port of the pump. An ejector device that mixes gas, a mixer device that stirs the gas-liquid discharged from the pump, and the gas-liquid agitated by the mixer device are mixed by vortex and reduced in pressure while being mixed in the tank. A water treatment system comprising a gas-liquid mixing device that discharges into a tank, wherein the gas-liquid mixing device supplies gas to the two-stage rotating flow forming section connected in series and the preceding rotating-flow forming section. A fluid introduction path for introducing a liquid, and the former rotary flow forming section has an annular gas-liquid mixing chamber having a conical protrusion on the bottom surface, and one end opened at the downstream end of the fluid introduction path, The left and right ends are open around the bottom of the conical protrusion. The gas-liquid is rotated in the gas-liquid mixing chamber around the conical protrusion by injecting the gas-liquid to the left and right sides of the conical protrusion through the left and right nozzle flow paths. The gas-liquid is mixed by the rotary flow, and the rotary flow forming portion at the latter stage is a tapered flow channel whose shape gradually increases along the gas-liquid flow direction and is rotated in the gas-liquid mixing chamber. The gas / liquid is guided to the taper flow path to further rotate the gas / liquid in the taper flow path, and the gas / liquid is mixed by the rotation flow.

  In the water treatment system according to the second aspect of the present invention, gas-liquid pressurization and mixing are performed in a total of three stages, that is, a pump and a gas-liquid mixing apparatus having a two-stage rotary flow forming section. Further, in the gas-liquid mixing device employed in this water treatment system, the gas-liquid rotates in the preceding annular gas-liquid mixing chamber, and this rotating gas-liquid further rotates in the subsequent tapered flow path. The gas and liquid are mixed efficiently by the vortex generated by the two-stage gas-liquid rotation.

  In the water treatment system according to the second aspect of the present invention, another tapered channel having a shape in which the channel diameter gradually increases along the gas-liquid flow direction is connected to the downstream end of the tapered channel. It is possible to adopt a configuration or a configuration in which an orifice channel for forming fine bubbles is connected to the downstream end of another tapered channel.

  In the water treatment system according to the first and second aspects of the present invention, a return flow path for returning the liquid discharged from the discharge side of the pump to the suction side of the pump is provided, and the flow path is provided in the middle of the flow path. You may employ | adopt the structure incorporating an ejector apparatus.

The water treatment system according to the first and second aspects of the present invention described above may be configured as an adjustment tank water treatment system that processes the liquid in the adjustment tank provided upstream of the aeration tank. If constituted in this way, since the amount of dissolved oxygen is increased in the adjustment tank, the propagation and growth of useful microorganisms can be promoted in the adjustment tank, and the digestion activity of microorganisms is started in the adjustment tank, By supplying the liquid with high dissolved oxygen concentration from the adjustment tank to the low dissolved oxygen concentration water area in the aeration tank, the active water area in the aeration tank suitable for useful microorganisms can be expanded, and the purification capacity in the water treatment facility Can be improved.

  In other words, the adjustment tank water treatment system as described above is obtained by performing high-concentration dissolved oxygen treatment on the adjustment tank such as the wastewater raw water flow rate adjustment tank provided in the front stage of the aeration tank in which microorganisms perform digestion activities. In addition, oxygen that is respired and consumed by a large amount of useful microorganisms is sufficiently supplied to a liquid such as water in a conditioned tank containing nutrients that the useful microorganisms will eat. The roles of the aeration tank, which is a place of digestive activity by useful microorganisms in the conventional water treatment facility, and the adjustment tank for adjusting the flow rate to the aeration tank were shared. However, in the present invention, the conventional adjustment tank is also used as an aeration tank, and the basic technical idea is different.

In the water treatment system according to the first and second inventions described above, since the pressurization of the pump applies a pressure of about 0.3 to 1.0 MPa in the flow path, the waste water containing a large amount of oil and a hardly decomposable substance are contained. Even in wastewater, the substances are atomized by pressurization / decompression, and emulsified / dispersed. For this reason, this water treatment system not only provides a high-concentration dissolved oxygen water body in the adjustment tank, but also, in addition to this, the digestion efficiency of the microorganism group that specifically decomposes oils and persistent substances, etc. It can also be promoted.

Moreover, in the water treatment system according to the first and second inventions described above, the tank is a regulation tank provided on the upstream side of the aeration tank, and the water treatment system injects a specific microorganism into the regulation tank. It is possible to employ a configuration including an injection means for the purpose.

  The injection means may include a microorganism culture tank for culturing specific microorganisms, and the specific microorganisms cultured and propagated in the microorganism culture tank may be injected into the adjustment tank. Moreover, the structure in which the specific microorganism of the microorganism culture tank is inject | poured into a control tank by the microorganisms injection apparatus which consists of a metering pump etc. can be employ | adopted. In this case, the injection means is constituted by the microorganism culture tank and the microorganism injection device.

  In addition, a series of steps, such as the introduction of a specific microorganism preparation into a microorganism culture tank as described above → the cultivation of a specific microorganism in a microorganism culture tank → the injection of a specific microorganism into a regulating tank by a microorganism injection device, shall be an automated system. You can also.

  Furthermore, as the injection means, in addition to the method using a microorganism culture tank as described above, as a method not using such a microorganism culture tank, for example, an operator periodically directs a specific microorganism preparation, that is, germinates. A method (first method) in which unspecified specific microorganisms are introduced into the adjustment tank, and a method (second method) in which specific microorganisms that have already germinated and cultured are quantitatively dropped into the adjustment tank by a microorganism injection device such as a metering pump. Shall be included.

  By the way, the residence time of the adjustment tank varies depending on the volume of the adjustment tank. In particular, since the first method germinates and cultures the specific microorganism in the adjustment tank, the residence time of the adjustment tank is sufficiently longer than the time until germination of the specific microorganism (approximately one day or more). It is desirable to adopt in some cases. On the other hand, in the second method, since the specific microorganisms already germinated and cultured are put into the adjustment tank, only when the residence time of the adjustment tank is sufficiently long compared to the time until germination of the specific microorganisms. However, it can be adopted even in a short case.

  The “specific microorganism” means a microorganism having the ability to specifically digest a hardly degradable substance. For example, product names BI-CHEM DC1002CG and DC1003FG of Novozymes Biologicals Japan Co., Ltd. DC1004TX, DC1005PP, DC1006KT, DC1008CB, DC1738CW, BI-CHEM, and the like.

In each of the water treatment systems according to the first and second aspects of the present invention, both a pump that sucks and pressurizes the liquid in the tank and discharges the liquid, and an ejector device that mixes gas into the liquid at the upstream side of the suction side of the pump And a mixer device that stirs the gas-liquid discharged from the pump and a gas-liquid mixing device that mixes the gas-liquid stirred in the mixer device by vortex, and the liquid is passed through the ejector device at the upstream side of the suction side of the pump. A configuration is adopted in which gas is mixed therein, the gas-liquid is pressurized with a pump, and supplied to the gas-liquid mixing device via a mixer device. For this reason, gas-liquid pressurization, agitation, and mixing are performed in three stages of a pump, a mixer device, and a gas-liquid mixing device, so that gas-liquid can be mixed efficiently throughout the system, and dissolved oxygen in the tank Increase concentration.

  In particular, according to the water treatment system according to the first aspect of the present invention, as a specific configuration of the gas-liquid mixing device constituting the system, the gas-liquid in the sealed container is not used without using the impeller, the nozzle, and the small hole. Since a gas-liquid mixing device that efficiently mixes gas and liquid using high-speed eddy current due to thin layer diffusion of water is used, water other than fresh water, such as slurry, natural water, and wastewater, is also treated. A processing system may be provided. Moreover, the gas-liquid mixing efficiency in such a gas-liquid mixing apparatus increases the gas-liquid mixing efficiency of the entire system, and the dissolved oxygen concentration in the tank can be further increased. Furthermore, this gas-liquid mixing device mixes gas and liquid with a high-speed vortex formed by the introduced gas and liquid, and for gas introduction, forced air supply such as a compressor is not required, and no power is required. There are effects such as energy saving as a whole system.

  In addition, according to the water treatment system according to the second aspect of the present invention, as a specific configuration of the gas-liquid mixing device constituting the system, two-stage gas-liquid rotation is performed without using an impeller, a nozzle, or a small hole. Since the configuration in which gas and liquid are efficiently mixed by the eddy current generated by the above-described method can be provided, it is possible to provide a water treatment system for treating liquids other than fresh water, such as slurry liquid, natural water, and wastewater liquid. Moreover, the gas-liquid mixing efficiency in such a gas-liquid mixing apparatus increases the gas-liquid mixing efficiency of the entire system, and the dissolved oxygen concentration in the tank can be further increased. Furthermore, this gas-liquid mixing device mixes the gas and liquid by the two-stage rotation of the introduced gas and liquid, and does not require any power other than pumping the gas and liquid, so that the system as a whole can save energy. Has the effect of.

Further, in the first and second aspects of the present invention, a configuration is provided in which a return flow path for returning the liquid discharged from the discharge side of the pump to the suction side of the pump is provided, and an ejector device is incorporated in the flow path. Unlike the conventional method in which gas is sent directly to the suction side of the pump, the one used is because the mixture of gas and liquid is sent to the suction side of the pump. Even if a non-displacement type centrifugal pump (vortex pump) is used, it is possible to effectively prevent the efficiency of gas / liquid mixing from being reduced due to the idling of the pump or insufficient supply of gas / liquid from the pump to the gas / liquid mixing device. can do.

According to the water treatment system according to the first and second aspects of the present invention, efficient gas-liquid mixing in the gas-liquid mixing apparatus constituting the system and the gas-liquid mixing efficiency of the entire system are increased, and dissolution in the tank is performed. The oxygen concentration can be further increased. This gives a margin to the dissolved oxygen concentration in the tank liquid, so depending on the degree of contamination and the amount of difficult-to-decompose substances that are not good with standard activated sludge treatment methods such as oil contained in raw wastewater. With the effect of improving the propagation and activation of new microorganisms by the introduction of a microbial preparation that specifically decomposes, sufficient oxygen supply can be made even for the increasing oxygen demand. Therefore, by introducing the microbial preparation into the existing water treatment facility together with this system, there is a problem that occurs when the amount of persistent degradable substances in the wastewater is mixed more than usual, that is, the wastewater treatment facility. It is possible to reduce or prevent the frequency of occurrence of situations such as exceeding drainage standards for facility treatment effluent water, which often occurred due to high load inflow exceeding the purification treatment capacity.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the accompanying drawings.

  In this specification, from the viewpoint of draining wastewater from the factory and purifying water purified by the wastewater treatment facility to a river or sewer near the facility, the upstream side of the wastewater treatment facility is excluding the explanation of the following experiment. The terminology is used differently, such as “waste water” and “drainage” on the downstream side of the facility.

  FIG. 1 is a schematic configuration diagram of a wastewater treatment facility to which the water treatment system of the present invention is applied. The wastewater treatment facility S includes a conditioning tank 1 upstream, an aeration tank 2 downstream thereof, and a precipitation tank 3 further downstream thereof. It is configured.

  The adjustment tank 1 not only functions as a water level adjusting means for adjusting the water level of the aeration tank 2 positioned downstream thereof, but also includes a water treatment system S1 or S2 ( 2) or the water treatment system S3 of the adjustment tank 1 including the gas-liquid mixing device 10B (see FIG. 9) generates fine bubbles in the adjustment tank 1 and increases the amount of dissolved oxygen in the adjustment tank 1. It also has a function to make.

  The aeration tank 2 is supplied with a gas-liquid whose dissolved oxygen amount is increased in the adjustment tank 1 via the pump 4, and a water treatment system S4 or S5 including a gas-liquid mixing apparatus 10C described later (FIGS. 10 and 12). Activated sludge (mud containing microorganisms in the presence of oxygen) is supplied from the sedimentation tank 3 via either one or both of them, and the digesting activity of the soil substances by the useful microorganisms is performed.

  The settling tank 3 separates the sludge mixed solution supplied from the aeration tank 2 into activated sludge and supernatant liquid, and the separated activated sludge is supplied to the aeration tank via one or both of the water treatment systems S4 and S5. 2 or returned as excess sludge. The supernatant liquid is discharged as a treatment fluid to natural water, sewers, or reused as intermediate water.

  FIG. 2 is a system configuration diagram of the water treatment system of the adjustment tank 1 (hereinafter referred to as “adjustment tank water treatment system S1”). The adjustment tank water treatment system S1 includes first and second pumps 6 and 8 as pumps for sucking, pressurizing, and discharging the liquid in the adjustment tank 1, as well as an ejector device 7, a mixer device 9, and a gas-liquid mixture. A device 10A is provided.

  The first pump 6 is driven by a drive motor (not shown), sucks the liquid in the adjustment tank 1, and pumps it to the ejector device 7 through the water intake pipe 11.

  The ejector device 7 is a means for mixing a gas such as air containing oxygen (air in the present embodiment) into the liquid by natural intake air before the suction side 8A of the second pump 8. As an example of the configuration of this type of ejector device 7, the present water treatment system S1 employs the ejector device 7 having the structure shown in FIG. The ejector device 7 is not limited as long as the intake function is satisfied.

  The ejector device 7 shown in FIG. 1 includes a pipe body 13 incorporated in the middle of the water intake pipe line 11 (in the present embodiment, immediately before the suction side 8A of the second pump 8) via pipe joints 12A and 12B. And a gas introduction pipe 15 having one end opened downstream from the outer peripheral surface of the tube body 13 and the other end opened to the atmosphere side. In addition, you may comprise so that high concentration oxygen may be mixed in a liquid via this ejector apparatus 7 by connecting the other end of the gas introduction pipe | tube 15 to the supply source of high concentration oxygen.

  The ejector device 7 having the structure described above introduces a liquid from the intake pipe 11 into the pipe body 13 and squeezes it with the throttle part 14, thereby forming a high-speed flow downstream of the throttle part 14. Air is naturally aspirated and mixed into the liquid (natural aspiration type). Therefore, a power system such as a forced air supply system using a compressor or the like is not necessary.

  The second pump 8 is driven by a motor 16 different from the first pump 6, sucks the gas / liquid supplied from the ejector device 7, and pumps the gas / liquid to the mixer device 9 through the water supply pipe 17. To do.

  The mixer device 9 agitates the gas and liquid supplied from the second pump 8. As an example of the configuration of the mixer apparatus 9, the water treatment system S1 employs the mixer apparatus 9 having the structure shown in FIG. The mixer device 9 does not have to have this structure.

  The mixer device 9 shown in FIG. 1 includes a pipe body 19 connected to the downstream end of the water supply pipe line 17 via a pipe joint 18A, and a stirring means 20 provided inside the pipe body 19. As shown in FIGS. 4C to 4G, a plurality of stirring plates 22 having through holes 21 through which liquid passes and annular spacers 23 are alternately installed along the gas-liquid flow direction. The gas and liquid are agitated by the fixed plurality of agitation plates 22 to generate turbulent flow in the tube body 19 and mix the gas and liquid.

  The gas-liquid mixing apparatus 10A is installed inside the adjustment tank 1 as shown in FIG. 2, and as shown in FIGS. 5 (a), 5 (b), and 5 (c), (1) a cylindrical sealed container 24 and ( 2) A fluid introduction pipe that is connected to the downstream end of the mixer device 9 (specifically, the downstream end of the tube body 19) via a pipe joint 18B and introduces the gas-liquid stirred by the mixer device 9 into the sealed container 24. 25, (3) a fluid discharge port 26 for discharging gas and liquid from the sealed container 24, and (4) a discharge cylinder 27 attached to the fluid discharge port 26. Mix the liquid.

  As shown in FIG. 5C, the fluid introduction tube 25 penetrates the inner and outer peripheral walls of the sealed container 24 and enters the sealed container 24, and the leading end of the entered fluid introduction tube 25 is sealed as the fluid introduction port 28. The container 24 is configured to open close to the inner bottom surface. For this reason, the gas-liquid introduced into the sealed container 24 from the fluid inlet 28 is thinly diffused in a fan shape in the left-right direction (the left-right inner end face direction of the sealed container 24) along the inner arc surface of the sealed container 24, A high-speed vortex is formed in the sealed container 24. Further, since the high-speed vortex flows in the direction of the inner end face of the sealed container 24 (see FIG. 5A), the fluid discharge port 26 opens at the end face of the sealed container 24.

  The fluid discharge port 26 employs a nozzle structure 30 shown in FIGS. This nozzle structure 30 is provided with one suction hole (hereinafter referred to as “suction hole 31”) formed of an orifice at the center of the fluid discharge port 26, and forms fine bubbles around the suction hole 31. For this purpose, at least two or more ejection holes (hereinafter referred to as “ejection holes 32”) are provided. According to the nozzle structure 30 having such a hole configuration, a drawing vortex accompanied by a gas column extending from the inside of the sealed container 24 to the outside through the central suction hole 31 is created, and the gas outside the sealed container 24 is sealed through this gas column. It becomes easy to enter the container 24, and as a result, the gas-liquid in the sealed container 24 can be efficiently discharged from the ejection hole 32.

  One end of the discharge cylinder 27 opens to the fluid discharge side negative pressure portion of the fluid discharge port 26, and the other end opens into the adjustment tank 1. When such a discharge cylinder 27 is not provided in the fluid discharge port 26, liquid other than gas and liquid discharged from the discharge hole 32 is also sucked into the suction hole 31, and a large liquid mixture is sucked into the suction hole 31. There is a possibility of clogging. On the other hand, when the discharge cylinder 27 is provided in the fluid discharge port 26, only the gas in the fluid discharged from the ejection hole 32 is sucked from the suction hole 31, and the inside of the discharge cylinder 27 is discharged from the ejection hole 32. Therefore, the suction hole 31 is not clogged due to the suction of a large liquid mixture.

  In the adjusted tank water treatment system S1 having the above-described configuration, the second pump 8 is continuously used in the entire range from the system startup to the stop, but the first pump 6 is used when the system is started up. Thus, it is used only when the inside of the intake pipe 11 is empty and it is difficult to suck up the liquid in the adjustment tank 1 only by the second pump 8. Such operation control of the 1st and 2nd pumps 6 and 8 is performed by the control panel 100 (refer FIG. 2) which controls operation | movement, such as starting and a stop of adjustment tank water treatment system S1.

  Further, in the present embodiment, as shown in FIG. 2, a flow meter 101 with a sensor is incorporated in the middle of the gas introduction tube 15, and the amount of gas sucked by the gas introduction tube 15 is detected by a sensor (not shown) of the flow meter 101. By sending it to the control panel 100, the control panel 100 and the flow meter 101 can monitor the amount of air mixed into the liquid.

  The processing operation and action of the entire adjustment tank water treatment system S1 configured as described above will be described with reference to FIGS.

  According to this adjustment tank water treatment system S1, the liquid in the adjustment tank 1 passes through the ejector device 7 and is sucked into the suction side 8A of the second pump 8. The liquid sucked in includes air taken in by natural suction when passing through the ejector device 7, and the liquid (gas-liquid) containing this air is pressurized in the second pump 8, After being pumped from the discharge side 8B of the pump 8 to the mixer device 9 and further stirred in the mixer device 9, it is supplied to the gas-liquid mixing device 10A.

  As described above, the gas-liquid supplied from the mixer device 9 to the gas-liquid mixing device 10A is introduced into the sealed container 24 through the fluid introduction pipe 25 as shown in FIG. Then, it diffuses into a fan-like thin layer in the left-right direction, and is discharged into the adjusting tank 1 from the ejection hole 32 of the fluid ejection port 26 through the ejection cylinder 27 as a high-speed vortex. At this time, the gas and liquid are efficiently mixed in the sealed container 24 by the high-speed vortex. Further, in the vicinity of the fluid discharge port 26, complicated turbulent flow is generated by the operation of gas-liquid discharge and suction through the suction hole 31 and the ejection hole 32, and the mixing of the gas-liquid is further promoted by this turbulent flow. . The gas-liquid mixed efficiently and sufficiently in this way is discharged as a high-speed flow from the ejection holes 32 to form a large amount of fine bubbles. For this reason, the amount of dissolved oxygen in the adjustment tank 1 is increased, and an environment suitable for propagation and growth of useful microorganisms is created in the adjustment tank 1.

  As described above, the adjustment tank water treatment system S1 includes the pump 8 that sucks and pressurizes the liquid in the adjustment tank 1 and discharges it, and the ejector device 7 that mixes gas into the liquid at the upstream side of the suction side of the pump 8. , A mixer device 9 for stirring the gas-liquid discharged from the pump 8 and a gas-liquid mixing device 10A for mixing the gas-liquid stirred by the mixer device 9 by vortex, and an ejector device at the upstream side of the suction side of the pump 8 In this configuration, a gas is mixed into the liquid via 7, the gas / liquid is pressurized by the pump 8, and supplied to the gas / liquid mixing device 10 </ b> A via the mixer device 9. For this reason, since gas-liquid pressurization, stirring, and mixing are performed in three stages of the pump 8, the mixer device 9, and the gas-liquid mixing device 10A, the gas-liquid can be efficiently mixed in the entire system, and the adjustment tank 1 Increase the dissolved oxygen concentration inside.

  FIG. 7 is a system configuration diagram of another adjustment tank water treatment system S2. The adjustment tank water treatment system S2 in the figure is provided with a return pipe 33 that returns from the water supply pipe 17 to the water intake pipe 11, thereby forming a diversion part on the discharge side 8B of the pump 8, and A return flow path for returning a part of the gas and liquid discharged from the discharge side 8B to the suction side 8A of the pump 8 is formed, and further, the natural flow described above is provided in the flow dividing section, specifically in the middle of the return pipe 33. By incorporating the intake-type ejector device 7, the liquid (gas-liquid) mixed with air by natural intake in the ejector device 7 is sucked into the second pump 8 and pressurized in the pump 8. It is configured to be supplied to the gas-liquid mixing device 10A side through the mixer device 9. Since it is the same as that of adjustment tank water treatment system S1 of FIG. 2 about another structure, the same code | symbol is attached | subjected to the same member and the detailed description is abbreviate | omitted. In addition, the upper limit of the gas supply amount by the ejector device 7 is set to an amount that does not cause trouble such as idling of the pump.

  In particular, according to the adjustment tank water treatment system S2 of FIG. 7 having the above-described configuration, the gas and the liquid mixture are not directly fed to the suction side 8A of the second pump 8, but the second pump. As a specific example of the second pump 8, for example, even when a non-volumetric centrifugal pump (spiral pump) that is most commonly used at present is adopted, It is possible to effectively prevent a reduction in efficiency of gas-liquid mixing due to idling or insufficient supply of gas-liquid from the centrifugal pump to the gas-liquid mixing apparatus 10A, and the gas-liquid mixing can be performed efficiently by the gas-liquid mixing apparatus 10A. Further, since the gas-liquid stirring is performed in the second pump 8, there is an advantage that the degree of gas-liquid mixing is further increased.

  FIG. 8 is a cross-sectional view of another gas-liquid mixing apparatus 10B, and FIG. 9 is a system configuration diagram of a regulating tank water treatment system S3 including the gas-liquid mixing apparatus 10B of FIG. In addition, in adjustment tank water treatment system S3 of FIG. 9, since it is the same as that of the thing of FIG. 7 about system components other than the gas-liquid mixing apparatus 10B, the same code | symbol is attached | subjected to the same member and the detailed description The gas-liquid mixing apparatus 10B of FIG. 8 having a different configuration will be described in detail.

  The gas-liquid mixing device 10B of FIG. 8 is configured to gas-liquid transfer to the rotary flow forming unit 41A in the preceding stage of the two stages of rotary flow forming units 41A and 41B and the two stages of rotary flow forming units 41A and 41B. And the gas-liquid is continuously rotated by the two-stage rotary flow forming portions 41A and 41B, and the gas-liquid is vortexed by the two-stage gas-liquid rotation. Mix.

  The upper end of the fluid introduction path 42 is connected to the water supply pipe line 17 through a pipe joint 43A.

  The front rotational flow forming portion 41A has an annular gas-liquid mixing chamber 45 having a conical protrusion 44 at the center of the bottom surface, one end opened at the downstream end of the fluid introduction path 42, and the other end at the conical protrusion 44. Left and right nozzle flow paths 46 opened around the bottom of the bottom, and by injecting gas and liquid to the left and right sides of the conical protrusion 44 through the left and right nozzle flow paths 46, the conical protrusion 44 is centered. The gas and liquid are rotated and mixed in the gas and liquid mixing chamber 45.

  The gas-liquid rotating in the gas-liquid mixing chamber 45 as described above has an annular gap inclined flow path 48 formed by the tip end portion of the conical protrusion 44 and the tapered hole 47 inclined similarly to this, and Through the rotary flow passage channel 49 communicating with the gap inclined channel 48, the gas is further supplied to the subsequent rotary flow forming part 41B.

  The downstream rotational flow forming portion 41B includes a first tapered flow channel 50 having a shape in which the flow channel diameter gradually increases along the gas-liquid flow direction, and the annular gap inclined flow channel 48 and the rotational flow passage flow channel. The gas-liquid supplied through 49, that is, the gas-liquid rotated and mixed in the gas-liquid mixing chamber 45 is further rotated and mixed in the rotary flow passage channel 49 and introduced into the first taper channel 50.

  A second taper channel 51 is connected to the downstream end of the first taper channel 50, and an orifice channel 52 for forming fine bubbles at the downstream end of the second taper channel 51. Is connected. Since the second taper channel 51 has a shape in which the channel diameter gradually decreases along the gas-liquid flow direction, the gas-liquid passing through the second taper channel 51 is accelerated to generate a high-speed vortex flow. Then, it is introduced into the orifice channel 52 and discharged from the orifice channel 52 to form a large amount of fine bubbles.

  The gas-liquid mixing apparatus 10B is characterized by the shape and configuration of its fluid passage. The specific component configuration is one example and various types are conceivable. In this embodiment, the system which divides | segments and assembles the gas-liquid mixing apparatus 10B into several parts components as the component structure was employ | adopted. Specifically, as shown in FIG. 8, this system includes upper, middle and lower blocks 54, 55, 56, an orifice plate 57, and a cap attached to the lower block 56 connected in series by a connecting cylinder 53. 58, and the fluid introduction passage 42 and the left and right nozzle passages 46 are formed in the upper block 54.

  For the annular gas-liquid mixing chamber 45, a recess 59 is formed on the joint surface of the upper block 54 to which the middle block 55 is joined, and the conical protrusion 44 is formed at the center of the bottom of the recess 59. Thus, a configuration in which the annular gas-liquid mixing chamber 45 is formed at the joint between the upper block 54 and the middle block 55 is adopted.

  Further, the rotary flow passage channel 49 and the first taper channel 50 are formed in the middle block 55, and the second taper channel 51 is formed in the lower block 56. For the orifice channel 52, the orifice plate 57 is disposed between the lower block 56 and the cap 58, and the upstream end of the orifice channel 52 formed in the orifice plate 57 has the second tapered flow. It was configured to communicate with the downstream end of the channel 51. Further, in order to discharge gas liquid and fine bubbles from the downstream end of the orifice channel 52 to the outside of the apparatus 10B, the cap 58 is formed with a discharge hole 60 communicating with the downstream end of the orifice channel 52 and the outside. As long as the main flow path structure can be configured, the above-described component configuration is not necessarily required.

  According to the gas-liquid mixing apparatus 10B of FIG. 8 described above, the gas-liquid is rotated in the front-stage gas-liquid mixing chamber 45, and is further rotated in the first-stage taper channel 50 in the subsequent stage. Since the gas and liquid are mixed by the vortex generated by the two-stage rotation, the gas and liquid can be mixed and dissolved efficiently, and fine bubbles can be generated, and the dissolved oxygen concentration in the liquid can be increased.

  FIG. 10 is a system configuration diagram of a water treatment system (hereinafter referred to as “returned sludge activated water treatment system”) that activates sludge that is returned from the settling tank 3 to the aeration tank 2, and this returned sludge activated water treatment system. S4 includes a first pump 6, a second pump 8, and a gas-liquid mixing device 10C.

  In this return sludge activated water treatment system S4, the first pump 6 and the second pump 8 are driven by separate motors 16 to suck the sludge in the sedimentation tank 3 through the intake pipe 11 and mix the gas and liquid. Pump to device 10C. In addition, since the motor of the pump 6 is built in the pump, illustration is abbreviate | omitted.

  Even in the present return sludge activated water treatment system S4, the second pump 8 is continuously used in the entire range from the system startup to the stop, but the first pump 6 is used at the time of system startup, etc. Thus, it is used only when the intake pipe 11 is empty and it is difficult to suck up the gas-liquid in the sedimentation tank 3 only by the second pump 8.

  The gas-liquid mixing device 10C is installed on the upper surface of the aeration tank 2 as shown in FIG. 10, and as shown in FIG. 11, (1) a cylindrical sealed container 24, and (2) a second A fluid introduction pipe 25 connected to the discharge side 8B of the pump 8 via a pipe joint 18B and introducing the liquid discharged from the discharge side 8B of the second pump 8 into the sealed container 24; (3) in the sealed container 24; A fluid discharge port 26 that discharges gas and liquid from the outside, (4) a discharge cylinder 27 attached to the fluid discharge port 26, and (5) a gas introduction pipe 15 attached to the discharge cylinder 27. The

  Also in the gas-liquid mixing apparatus 10 </ b> C, the fluid introduction pipe 25 penetrates the inner and outer peripheral walls of the sealed container 24 and enters the sealed container 24, and the leading end of the entered fluid introduction pipe 25 is sealed as the fluid introduction port 28. The container 24 is configured to open close to the inner bottom surface. For this reason, the liquid introduced into the sealed container 24 from the fluid inlet 28 is diffused into a fan-like thin layer in the left-right direction (in the direction of the left and right inner end surfaces of the sealed container 24) along the inner circular arc surface of the sealed container 24. A high-speed vortex is formed in the container 24. Further, since the high-speed vortex flows toward the inner end face of the sealed container 24, the fluid discharge port 26 opens at the end face of the sealed container 24.

  Also in the gas-liquid mixing apparatus 10C, the above-described nozzle structure 30 shown in FIG. 6 is provided in the fluid discharge port 26 from the viewpoint of improving the gas-liquid discharge efficiency and further improving the degree of gas-liquid mixing. Adopted. The detailed configuration of the nozzle structure 30 is omitted as described above.

  In the gas-liquid mixing apparatus 10C configured as described above, gas-liquid is ejected from the ejection holes 32 of the nozzle structure 30, and the downstream side of the fluid ejection port 26, specifically, the vicinity of the fluid ejection side of the ejection holes 32 becomes negative pressure. . In order to allow air to be naturally sucked from the gas introduction tube 15 using this negative pressure, one end of the gas introduction tube 15 opens to the fluid discharge side negative pressure portion of the fluid discharge port 26, and the gas introduction tube 15. The other end of was opened to the atmosphere side. Since the gas-liquid mixing apparatus 10C is also a natural intake type, a power system such as a forced supply type using a compressor or the like is not necessary.

  Further, in the vicinity of the fluid discharge port 26 of the gas-liquid mixing apparatus 10C, a gas suction operation through the gas introduction pipe 15 is added to the fluid discharge and suction operations performed through the suction hole 31 and the ejection hole 32, and the discharge is performed. A complicated turbulent flow is generated in the cylinder 27, the gas-liquid mixing is promoted, and the amount of dissolved oxygen in the fluid can be increased.

  This return sludge activated water treatment system S4 in FIG. 10 has a route (sludge return route 70) for returning sludge from the settling tank 3 to the aeration tank 2 by the pumps 8 and 6, the intake pipe 11 and the water supply pipe 17. A gas-liquid mixing device 10C is connected to the return port 17A for returning sludge to the aeration tank 2, and the activated return sludge is discharged from the gas-liquid mixing device 10C to the aeration tank 2 by increasing the dissolved oxygen concentration. It is configured to be supplied.

  According to the present return sludge activated water treatment system S4 having the above-described configuration, since the return sludge activated by increasing the dissolved oxygen concentration is discharged and supplied from the gas-liquid mixing device 10C to the aeration tank 2, the low dissolved oxygen concentration Can effectively prevent the generation of low dissolved oxygen concentration water area due to the return of sludge to the aeration tank 2, and the entire aeration tank 2 becomes a high concentration dissolved oxygen water area with high microbial activity. The purification capacity can be improved.

  FIG. 12 is a system configuration diagram of another return sludge activated water treatment system S5. The return sludge activated water treatment system S5 has a route (sludge return route 73) for returning the sludge from the settling tank 3 to the aeration tank 2 through the sludge return pipe 72 by the existing return sludge / return pump 71. 11 is connected to the discharge port 72A for returning sludge to the aeration tank 2. In this connection structure, the fluid introduction pipe 25 of the gas-liquid mixing apparatus 10C is connected to the return sludge discharge port 72A.

  The return sludge activated water treatment system S5 of FIG. 12 configured as described above is also configured to return the activated sludge activated by increasing the dissolved oxygen concentration from the gas-liquid mixing device 10C to the aeration tank 2, similarly to the system S4 of FIG. Discharge supply. At this time, the return sludge discharge port 72A is provided in the upper part of the water surface upstream of the aeration tank 2 as shown in FIG. 12, so that the gas-liquid mixing apparatus 10C of FIG. Discharge and supply return sludge activated by increasing the dissolved oxygen concentration. Therefore, according to this return sludge activated water treatment system S5 of FIG. 12, the low dissolved oxygen concentration water area in the previous stage of the aeration tank 2 which has been a factor of lowering the treatment capacity of the aeration tank 2 is improved to the high dissolved oxygen concentration water area. Therefore, the entire aeration tank 2 becomes a high-concentration dissolved oxygen water region with high microbial activity, and the purification capacity in the water treatment facility can be improved.

  In particular, the return sludge activated water treatment system S5 of FIG. 12 is provided to the aeration tank 2 when the return sludge / return pump 71 has the ability to constantly discharge a pressure of 0.2 to 0.6 MPa. 11 can be configured by simply connecting the gas-liquid mixing device 10C of FIG. 11 to the return sludge discharge port 72A. In addition to the control system for controlling the existing return sludge / return pump 71, there is a special control system. There is also an advantage that the purification capability in the water treatment facility can be improved with a simple equipment configuration.

<Explanation of experimental sample>
FIG. 13 is an explanatory diagram of an experimental sample when the effect experiment of the nozzle structure 30 shown in FIG. 6 is performed. (A) is the nozzle structure 30, and (b) is used for comparison with the nozzle structure 30. A nozzle structure (hereinafter referred to as “comparative nozzle structure 90”) is shown. The comparison nozzle structure 90 has no distinction between the suction hole 31 and the ejection hole 32 as in the present nozzle structure 30, and has a single hole 91 provided at the center of the nozzle structure.

In both the nozzle structure 30 and the comparative nozzle structure 90, the thickness of each nozzle (the length of each hole 31, 32, 91) was 3 mm, and the experiment was performed under the same apparatus conditions except for these two nozzle structures. . That is, the experiment was performed on the apparatus 10A of FIG. 5 employing the nozzle structure 30, and the experiment was performed by removing the nozzle structure 30 from the apparatus 10A and attaching the comparative nozzle structure 90 instead. In addition, the area of each hole 31, 32, 91 of this nozzle structure 30 and the comparison nozzle structure 90 is as follows.
(i) This nozzle structure
Area of suction hole: 19.165mm ²
Area of the ejection hole: 28.26mm ² (7.065mm ² (1 hole) × 4 total area)
(ii) Comparison nozzle structure
Area of one hole: 45.3416mm ²

<Conditions for Experiment (1)>
In this experiment (1), the fluid ejected from the nozzle structure 30 and the comparative nozzle structure 90 is tap water, the tap water is stored in a water tank, and the pressure is pumped in a range of 0.1 MPa to 0.6 MPa in increments of 0.1 MPa. Then, tap water was gradually introduced into the fluid introduction pipe 25 (see FIG. 5) of the apparatus 10A. The amount of drainage was calculated by measuring the weight of water drained into a polybucket and calculating the capacity with a specific gravity of 1.0.

<Observation result of discharge status of this nozzle structure in Experiment (1)>
When tap water of 0.1 MPa was introduced, it was confirmed that tap water was discharged from all four ejection holes 32, but that tap water was also slightly discharged from the suction hole 31 at the center of the nozzle structure. When the pressure of tap water to be introduced was 0.2 MPa or more, tap water was discharged only from the four ejection holes 32, and there was no drainage from the suction holes 31. In this situation, one of the four ejection holes 32 was closed with a finger, observed from the side, and the presence or absence of ejection from the suction hole 31 was confirmed.

<Comparison of emissions in Experiment (1)>
As shown in FIG. 14, the measurement of the drainage amount at each pressure was repeated six times, and the average drainage amount and the standard deviation were calculated. From 0.1 MPa to 0.6 MPa, the drainage amount of the nozzle structure 30 and the comparative nozzle structure 90 at each pressure increased from 1.5% to 2.5% in the average drainage amount of the nozzle structure compared to the comparative nozzle structure. . When this difference was compared, from FIG. 15 , a significant difference was observed at all pressures by Student's t test (α <0.05; two-sided test). In this test, as described above, the ejection holes in the nozzle structure 30 and the comparative nozzle structure 90 (only the four ejection holes 32 in the present nozzle structure 30 and one hole 91 in the comparative nozzle structure 90). In comparison of the simple areas, the comparative nozzle structure 90 has an area about 1.6 times that of the present nozzle structure 30, but the amount of drainage is reversed, and the amount of drainage is greater in the present nozzle structure 30. Strictly speaking, it is only necessary to measure the amount of soot suction and discharge generated in one suction hole 31 in the center of the nozzle structure, but this measurement is impossible. Therefore, it can be seen from the area ratio of the ejection holes 32 that even if the nozzle structure has a hole having a large area reliably, the discharge efficiency can be suppressed if it is a single hole.

<Conditions for Experiment (2)>
In this experiment (2), an apparatus 10A (see FIG. 5) that employs the nozzle structure 30 with a large tank of 2t capacity, 1t of tap water, and a pressure of 0.3 to 0.4 MPa via a pressure pump. The tap water was discharged from the apparatus 10A employing the comparative nozzle structure 90 into the same water tank. At the same time, 100 g (dry weight) of sand (particle size: 0.2 to 1.7 mm) was sucked from the intake port of the pressure pump for 1 minute. The increase in dissolved oxygen concentration over time was measured with a dissolved oxygen meter.

<Result of Experiment (2)>
In the gas-liquid mixing apparatus 10A (hereinafter referred to as “this apparatus”) adopting this nozzle structure, 17 g (dry weight) of sand out of 100 g (dry weight) sucked from the intake port of the pressure pump was discharged. . When this apparatus 10A was disassembled, 28 g (dry weight) of sand was recovered from the inside of the sealed container 24, but no sand clogging occurred in the suction holes 31, the ejection holes 32, and the like. It is considered that the sand remained in the sealed container 24 due to the centrifugal separation caused by the vortex generated in the sealed container 24. The remaining 55 g of sand is probably present in the pressure pump and piping.

The amount of drainage of this device was about 30-40 L / min, but it was discharged from this device in about 5 minutes for 1 t of water, and the water tank was filled with fine bubbles. The change in dissolved oxygen concentration over time is as shown in FIG. From FIG. 16 , according to this apparatus, since the dissolved oxygen concentration in a water tank has risen before all the tap water stored in the water tank is processed in this apparatus, the drainage discharge force from this apparatus. It is thought that the dissolved oxygen concentration increased from the beginning of the operation of the device due to the water flow caused by In addition, the water temperature at the time of this experiment is 25.7 ° C, and the dissolved oxygen saturation at this time is 8.02 mg / L. Therefore, according to this device, the dissolved oxygen in the water tank becomes saturated immediately after the start of operation of this device. Showed a saturation amount of about 120%, indicating that sufficient gas-liquid mixing was performed.

  17 to 22 are experimental data when a comparative experiment is performed on the adjusted tank water treatment system of FIG. 9 and the water treatment system of Patent Document 1. FIG. As can be seen from FIGS. 17 to 22, in the adjusted tank water treatment system of FIG. 9, the peak of the average bubble diameter increases toward the minimum bubble diameter as the pressurizing force (supply pressure) of the second pump increases. As a result, it was observed that more fine bubbles were formed.

  By the way, in general, the composition, flow rate, and concentration of factory wastewater are rarely constant throughout the year. The quality and quantity of factory wastewater is constantly changing according to the type and quantity of factory products and the fluctuations in demand for each item. For example, when the contents of factory wastewater have changed significantly due to changes in the product, the type and composition of the microflora that acts on the purification treatment must be changed in the aeration tank 2 of the wastewater treatment facility S shown in FIG. No.

  However, the microflora in the aeration tank 2 is not immediately replaced with an appropriate microflora as the wastewater changes, but is replaced after an appropriate time lag, or the factory wastewater. There is a case where the microbiota does not catch up with the change of the aeration tank and the purification function of the aeration tank 2 is destroyed. In particular, in the latter case, an increase in degradable substances for standard activated sludge treatment, such as oil contained in wastewater, causes direct deterioration in the treated effluent from the wastewater treatment facility S. Give the water quality environment a load higher than the standard value.

  In order to avoid such a situation, it is necessary to store the microflora in the aeration tank 2 so as to maintain a certain purification capacity. It is necessary to prepare a microorganism having the ability to specifically digest a substance, that is, the specific microorganism described above.

  Therefore, in the wastewater treatment facility S ′ of FIG. 23, the specific microorganism is injected into the adjustment tank water treatment system S1, S2 or S3 (see FIG. 1) of the wastewater treatment facility S of FIG. Injecting means 92 is incorporated, and the injecting means 92 is configured to be able to inject the specific microorganisms into the adjustment tank 1 at any time. Since the basic configuration of the wastewater treatment facility S ′ is the same as that of the wastewater treatment facility S of FIG. 1, the same reference numerals are given to the same members, and detailed descriptions thereof are omitted.

  In short, in the present wastewater treatment facility S ′ of FIG. 23, the amount of dissolved oxygen (concentration) in the adjustment tank 1 is increased by the generation of fine bubbles in the adjustment tank 1 as in the wastewater treatment facility S of FIG. Therefore, the adjustment tank 1 can always maintain the growth environment of microorganisms in a state with a margin. For this reason, this wastewater treatment facility S ′ is configured so that the microorganism preparation containing the specific microorganism can be introduced into the adjustment tank 1 by the injection means 92 as described above, and only the injection means 92 is operated according to the change of the factory wastewater. This makes it possible to respond immediately to irregular changes in factory wastewater such as factory wastewater containing persistent substances.

  The injection means 92 shown in FIG. 23 includes a microorganism culture tank 92A to which air is supplied by a blower 92C and a microorganism injection apparatus 92B composed of a metering pump or the like, and the microorganism culture tank 92A has a specific microorganism preparation. The specific microorganisms germinated, cultured and proliferated in the tank 92A are injected into the adjustment tank 1 by the microorganism injection device 92. Oxygen necessary for germination, culture and growth of a specific microorganism is supplied by the blower 92C.

  Regarding the capacity of the microbial culture layer 92A, an injection mode (so-called immune retention function) in which a small amount of active specific microorganisms are always injected into the adjustment tank 1 and an injection that increases the injection dose of the specific microorganisms only during irregular wastewater. It is preferable to set a large size so as to be compatible with both the form (so-called prescription).

  Moreover, in order to avoid that the carrier used for adhering and holding the specific microorganisms subjected to the dormant treatment is mixed into the adjustment tank 1, the microorganism culture that supplies the adjustment tank 1 with treated water containing the specific microorganisms It is desirable to provide a net having an opening of about 1 mm to 2 mm as a filter (not shown) on the outlet side of the tank 92A. This filter has a removable structure so that it can be easily cleaned.

  FIG. 24 is an explanatory diagram of a configuration example in which the injection means 92 is incorporated in the adjustment tank water treatment system S1 of FIG. 2, and FIG. 25 is a configuration example in which the injection means 92 is incorporated in the adjustment tank water treatment system S2 of FIG. It is explanatory drawing of. In any of these examples of incorporation, a specific configuration of the injection means 92 employs a method in which a specific microorganism is germinated and cultured in the microorganism culture tank 92A, and the propagated specific microorganism is injected into the adjustment tank 1. A method that does not use the microorganism culture tank 92A can also be adopted. As this type of method, for example, a method in which an operator periodically inputs a specific microorganism preparation, that is, a specific microorganism that has not germinated, into the adjustment tank 1 (first method), or a specific microorganism that has already germinated and cultured. A method (second method) in which a constant amount is dropped onto the adjustment tank 1 by the microorganism injection device 92B is conceivable, and any method may be adopted.

  By the way, in the case of the first method, it is sufficient that the specific microorganism can immediately start digestion activity immediately after the specific microorganism preparation is put into the adjustment tank 1, but many microorganism preparations are subjected to a dormancy treatment. The same applies to the specific microorganism preparation used in the present embodiment. Since it takes about a day or more until the specific microorganism wakes up from dormancy (germination), the first method may be adopted when the residence time of the adjustment tank 1 is sufficiently longer than the time until the germination of the specific microorganism. desirable. On the other hand, in the second method, since the specific microorganisms already germinated and cultured are put into the adjustment tank 1, the residence time of the adjustment tank 1 is sufficiently longer than the time until germination of the specific microorganisms. Not only the case but also a short case can be adopted.

The schematic block diagram of the wastewater treatment facility to which the water treatment system which concerns on this invention is applied. The system block diagram of an adjustment tank water treatment system. Sectional drawing of an ejector apparatus. Sectional drawing of a mixer apparatus. FIG. 5 is an explanatory view of an embodiment of a gas-liquid mixing device constituting the water treatment system according to the present invention, wherein (a) is a cross-sectional view of the gas-liquid mixing device, (b) is a view as viewed from arrow B, (c) ) Is a cross-sectional view taken along the line cc. It is explanatory drawing of a nozzle structure, (a) is a front view of a nozzle structure, (b) is sectional drawing of a nozzle structure. The system block diagram of another adjustment tank water treatment system. It is sectional drawing of other embodiment of a gas-liquid mixing apparatus. The system block diagram of the adjustment tank water treatment system containing the gas-liquid mixing apparatus of FIG. The system block diagram of a return sludge activated water treatment system. Explanatory drawing of the gas-liquid mixing apparatus which comprises the return sludge activated water processing system of FIG. The system block diagram of another return sludge activated water treatment system. FIG. 13 is an explanatory diagram of an experimental sample when the effect experiment of the present nozzle structure shown in FIG. 6 is performed, (a) is a front view and a side view of the nozzle structure, and (b) is a front view of the comparative nozzle structure. It is a figure and its side view. The comparison figure of discharge amount (experiment data) of this nozzle structure and a comparison nozzle structure. FIG. 3 is a comparison diagram of discharge amounts of the present nozzle structure and a comparative nozzle structure by student t test. Explanatory drawing of the experimental data which showed the change of the dissolved oxygen concentration with the time passage from an apparatus operation start at the time of using the gas-liquid mixing apparatus which employ | adopted this nozzle structure. FIG. 17 is experimental data when a comparative experiment is performed on the adjustment tank water treatment system of FIG. 9 and the water treatment system of Patent Document 1, and is a graph showing the generation distribution of bubbles (pressure condition by collecting slide glass) At 0.3 MPa). FIG. 18 is experimental data when a comparative experiment is performed on the adjustment tank water treatment system of FIG. 9 and the water treatment system of Patent Document 1, and is a graph showing the generation distribution of bubbles (pressure condition by collecting slide glass) At 0.35 MPa). FIG. 19 is experimental data when a comparative experiment is performed on the adjustment tank water treatment system of FIG. 9 and the water treatment system of Patent Document 1, and is a graph showing the bubble generation distribution (pressure condition by collecting slide glass). At 0.4 MPa). FIG. 10 is a graph showing the generation distribution of bubbles when a comparative experiment is performed for the adjustment tank water treatment system of FIG. 9 and the water treatment system of Patent Document 1 (when the pressure condition by taking a slide glass is 0.45 MPa). . FIG. 21 is experimental data when a comparative experiment is performed on the adjustment tank water treatment system of FIG. 9 and the water treatment system of Patent Document 1, and in 1 ml accompanying a change in the pressure (supply pressure) of the pump. It is a comparison figure of the generation amount of a fine bubble. FIG. 22 is experimental data when a comparative experiment is performed on the adjusted tank water treatment system of FIG. 9 and the water treatment system of Patent Document 1, and the average bubble diameter associated with the change in pump pressure (supply pressure) FIG. The schematic block diagram of the other wastewater treatment facility to which the water treatment system (including the injection means) according to the present invention is applied. Explanatory drawing of the structural example which integrated the injection | pouring means in the adjustment tank water treatment system of FIG. Explanatory drawing of the structural example which integrated the injection | pouring means in the adjustment tank water treatment system of FIG.

Explanation of symbols

S Wastewater treatment facilities S1, S2, S3, S4, S5 Water treatment system 1 Adjustment tank 2 Aeration tank 3 Precipitation tank 4 Pump 6 First pump 6A Pump suction port 6B Pump discharge port 7 Ejector device 8 Second pump 8A Pump Suction port 8B Pump discharge port 9 Mixer device 10A, 10B, 10C Gas-liquid mixing device 11 Intake pipe line 12A, 12B Joint 13 Tubing body 14 Throttle section 15 Gas introduction pipe 16 Motor 17 Water supply pipe line 17A Return sludge discharge port 18A Pipe Joint 18B Pipe joint 19 Tube body 20 Stirring means 21 Through hole 22 Stirring plate 23 Spacer 24 Sealed container 25 Fluid introduction pipe 26 Fluid discharge port 27 Discharge cylinder 28 Fluid introduction port 30 Nozzle structure 31 of fluid discharge port Suction hole (suction) Hole)
32 Hole for ejection (ejection hole)
33 Return pipes 41A and 41B Rotating flow forming part 42 Fluid introducing path 43A Pipe joint 44 Conical protrusion 45 Gas-liquid mixing chamber 46 Nozzle channel 47 Tapered hole 48 Gap inclined channel 49 Rotating flow channel 50 First taper Flow path 51 Second taper flow path 52 Orifice flow path 53 Connecting cylinder 54 Upper block 55 Middle block 56 Lower block 57 Orifice plate 58 Cap 59 Recess 60 Discharge hole 70 Sludge return route 71 Return sludge / return pump 72 Sludge return Pipe line 72A Return sludge outlet 73 Sludge return route 100 Control panel 101 Flow meter 90 Comparison nozzle structure 91 Hole 92 Injection means 92A Microorganism culture tank 92B Microorganism injection apparatus 92C Blower

Claims (9)

A pump that sucks, pressurizes and discharges the liquid in the tank;
An ejector device that mixes gas into the liquid at the upstream side of the suction side of the pump;
A mixer device for stirring the gas-liquid discharged from the pump;
A water treatment system comprising: a gas-liquid mixing device that is disposed in the tank and mixes the gas-liquid stirred by the mixer device by a vortex and depressurizes and discharges the gas-liquid mixture into the tank,
The gas-liquid mixing device is
A cylindrical sealed container;
A fluid introduction pipe for introducing gas-liquid into the sealed container;
A fluid discharge port for discharging gas and liquid from the inside of the sealed container,
In the state where the cylindrical sealed container is placed sideways, the fluid introduction pipe penetrates the side surface of the cylindrical sealed container and enters the sealed container, and the tip of the fluid introduction pipe that has entered as a fluid inlet, a water treatment system, characterized in that is provided so as to open and close to the inner bottom surface of the hermetic container of the cylindrical shape. The water treatment system according to claim 1, wherein the fluid discharge port has a nozzle structure having a suction hole provided at a center thereof and a plurality of ejection holes provided around the suction hole.   The water treatment system according to claim 2, wherein a diameter of the suction hole is larger than a diameter of the ejection hole.   4. The gas-liquid mixing device according to claim 2, wherein a discharge cylinder is attached to the fluid discharge side of the fluid discharge port. A pump that sucks, pressurizes and discharges the liquid in the tank;
An ejector device that mixes gas into the liquid at the discharge side diverting part or the front of the suction port of the pump;
A mixer device for stirring the gas-liquid discharged from the pump;
A water treatment system comprising: a gas-liquid mixing device that is disposed in the tank and mixes the gas-liquid stirred by the mixer device by a vortex and depressurizes and discharges the gas-liquid mixture into the tank,
The gas-liquid mixing device is
A two-stage rotating flow forming section connected in series;
A fluid introduction path for introducing gas and liquid into the preceding rotary flow forming section,
The former rotary flow forming part is
An annular gas-liquid mixing chamber having a conical protrusion on the bottom surface and left and right nozzle channels having one end opened at the downstream end of the fluid introduction path and the other end opened around the bottom of the conical protrusion. Then, by injecting gas and liquid to the left and right sides of the conical protrusion through the left and right nozzle channels, the gas and liquid are rotated around the conical protrusion in the gas-liquid mixing chamber, and the gas flows by the rotational flow. Mix the liquid,
The latter rotational flow forming part is
The taper channel has a shape in which the channel diameter gradually increases along the gas-liquid flow direction, and the gas-liquid rotated in the gas-liquid mixing chamber is guided to the taper channel in the taper channel. A water treatment system characterized by further rotating the gas and liquid and mixing the gas and liquid by the rotating flow. 6. A return flow path for returning the liquid discharged from the discharge side of the pump to the suction side of the pump is provided, and the ejector device is incorporated in the middle of the flow path. The water treatment system according to crab. The said tank is an adjustment tank provided in the upstream of an aeration tank, and each said water treatment system is comprised as an adjustment tank water treatment system which processes the liquid of an adjustment tank. The water treatment system in any one. The tank is an adjustment tank provided on the upstream side of the aeration tank,
The water treatment system according to claim 1, wherein the water treatment system includes an injecting unit for injecting the specific microorganism into the adjustment tank. The said injection | pouring means is equipped with the microorganism culture tank for cultivating a specific microorganism, It is comprised so that the specific microorganism culture | cultivated and propagated in this microorganism culture tank may be inject | poured into an adjustment tank. Water treatment system.

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