JP4099200B2 - Gas-liquid mixing device - Google Patents

Description

  The present invention relates to a gas-liquid mixing device that mixes a gas such as air containing oxygen and a liquid to increase the concentration of dissolved oxygen in the liquid.

  Conventionally, as this type of gas-liquid mixing technique, 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, since this method is 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, at least the impeller and its rotation support mechanism are required, The equipment configuration is complicated. Further, power for rotating the impeller is also required. 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 processed for gas-liquid mixing is mainly limited to fresh water having no inclusions, and liquids such as slurry liquids, natural water bodies, and wastewater cannot be processed.

  As this type of gas-liquid mixing technique, Patent Document 3 discloses that a gas-liquid introduction hole (22a) is formed in the peripheral wall of an elliptical spherical body (21), and the gas-liquid introduction hole (22a) is used. A method is described in which air-fuel mixture is swirled in the vessel body (21) by introducing the mixture water into the vessel body (21) to mix the gas and liquid (paragraph 0017 of the document 3). reference). However, according to this method, the mixed water introduced into the body (21) does not diffuse in a thin layer and does not form a high-speed vortex, so that the gas-liquid cannot be mixed efficiently and sufficiently. Furthermore, at the center of the vortex, a drawing vortex that inhibits the discharge of gas and liquid from the water jet holes (23, 24) is generated, and a large amount of gas and liquid cannot be discharged efficiently. There is also a problem that the vibration of the device and the accompanying noise occur. In this paragraph, the reference numerals in parentheses are those used in the document 3.

  In addition, this type of gas-liquid mixing technology includes a method in which pressure fluid is released from a small hole and rapidly decompressed and injected, a method in which pressure fluid is injected from the nozzle toward the wall and collided with the wall, There is also known a system in which fluids are jetted to cause the fluids to face each other. 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. However, it is not possible to treat 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 to eliminate the need for power other than that related to liquid transfer, and to easily and efficiently use a simple and compact device configuration. It is possible to mix the liquid and increase the dissolved oxygen concentration in the liquid. Furthermore, the slurry liquid, natural water (land water, seawater, brackish water), artificial water (dam reservoirs, marine animal breeding and aquaculture areas, The object is to provide a small and energy-saving gas-liquid mixing device capable of treating liquids other than fresh water, such as bath wastewater, household wastewater, and factory wastewater.

In order to achieve the above object, the present invention provides a cylindrical sealed container, a fluid introduction pipe for introducing gas and liquid into the sealed container, and a fluid discharge port for discharging gas and liquid from the sealed container to the outside. The fluid introduction pipe is provided at a central portion in the cylindrical axial direction of the sealed container in a state where the cylindrical sealed container is placed sideways, and a tip portion of the fluid introducing pipe is a side surface of the cylindrical sealed container. Penetrating into the inside of the sealed container, the tip of the fluid introduction pipe that has entered into the inside is provided as a fluid introduction port so as to open close to the inner bottom surface of the cylindrical sealed container , The fluid discharge port includes a suction hole penetrating the plate-like member and a plurality of ejection holes, the suction hole is located at the center of the plate-like member, and the plurality of ejection holes are arranged around the suction hole. Located above the fluid introduction pipe The gas-liquid introduced into the sealed container from the fluid inlet port is thinly diffused in a fan shape along the inner arc surface of the sealed container toward the left and right inner end surfaces of the sealed container, so that the cylindrical shaft of the sealed container is A thin-layer vortex is formed at the center, and the thin-layer vortex forms a drawing vortex with a gas column extending from the inside of the sealed container into the external gas-liquid through the central suction hole. The gas in the gas and liquid outside the sealed container is guided to the inside of the sealed container, so that the gas and liquid in the sealed container are easily discharged to the outside from the plurality of surrounding ejection holes .

In the present invention having the above-described configuration, since the tip portion of the fluid introduction tube opens as a fluid introduction port close to the inner bottom surface of the above-described sealed container, the fluid introduction tube is introduced into the sealed container through the fluid introduction port. The gas and liquid thus diffused in a thin layer in the shape of a fan from side to side along the inner surface of the sealed container forms a high-speed eddy current in the sealed container. Gas and liquid are efficiently mixed by such a high-speed vortex, and the dissolved oxygen concentration in the liquid is increased.

  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, of the non-water contaminants existing in the liquid such as natural waters and wastewater, large foreign matters mixed in fallen leaves and other wastewater should be at least sold on a commercially available wire mesh before introduction into the gas-liquid mixer. 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 in which the discharge cylinder is attached as described above, only the gas in the gas and liquid discharged from the ejection hole is sucked from the suction hole, and the vicinity of the outlet of the discharge cylinder is the gas and liquid discharged from the ejection hole. Since it is occupied, the effect of clogging the suction hole 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 the present invention , as described above, a configuration is adopted in which the distal end portion of the fluid introduction tube opens as a fluid introduction port close to the inner bottom surface of the sealed container. For this reason, 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. Thus, the gas-liquid can be efficiently mixed and the dissolved oxygen concentration in the liquid can be increased.

Further, according to the present invention, there is no impeller or the like in the sealed container, and the gas-liquid can be efficiently mixed as described above with a simple and compact device configuration of the sealed container and the fluid introduction pipe. Since the gas and liquid are mixed by the high-speed vortex formed by the gas and liquid, no power is required for mixing the gas and liquid, and since no impeller, nozzle, or small hole is used for mixing the gas and liquid, there is no constriction. Effects such as the ability to treat liquids other than fresh water can be obtained.

Furthermore, in the present invention , as described above, the gas-liquid is efficiently mixed by a high-speed vortex by thin-layer diffusion of the gas-liquid, and swirling blades, nozzles, small holes, etc. are used for gas-liquid mixing. Unlike products, there is no constriction that clogs or bites the mixture in the liquid, so even if the liquid is slurry liquid, natural water, waste water, etc., the mixture of large mixture in the liquid etc. It is possible to provide a gas-liquid mixing apparatus that does not cause a phenomenon that hinders the normal operation of the apparatus, has no parts that are worn by slurry, and has excellent reliability and durability.

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

  FIG. 1 is a schematic configuration diagram of a wastewater treatment facility to which the gas-liquid mixing apparatus of the present invention is applied. This wastewater treatment facility S includes an adjustment tank 1 upstream, an aeration tank 2 downstream thereof, and a precipitation tank further downstream thereof. 3 is provided.

  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 it.

  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 into the natural waters and 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 that suck, pressurize, and discharge the liquid in the adjustment tank 1, and ejector device 7, mixer device 9, and first pump. The gas-liquid mixing apparatus 10A according to the present invention is provided.

  The first pump 6 is driven by a drive motor (not shown), sucks the liquid in the adjustment tank 1, and pumps the liquid to the ejector device 7 through the 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 plurality of fixed stirring plates 22, thereby generating turbulent flow in the tube body 19 and mixing the gas and liquid.

  The gas-liquid mixing apparatus 10A according to the first aspect of the present invention is installed at the bottom of the adjustment tank 1 as shown in FIG. 2 and (1) a cylinder as shown in FIGS. 5 (a), 5 (b), and 5 (c). The airtight container 24 is connected to the downstream end of the mixer device 9 (specifically, the downstream end of the pipe body 19) via a pipe joint 18B, and the gas-liquid stirred by the mixer device 9 is sealed in the airtight container. 24, a fluid introduction pipe 25 to be introduced into the fluid container 24, (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. The gas-liquid stirred by the mixer device 9 is mixed.

  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, the thin layer diffuses in a fan shape in the left-right direction, and is discharged into the adjustment layer 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.

  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, so that a part of the gas and liquid discharged from the discharge side 8B of the second pump 8 is the same. A flow passage returning to the suction side 8A of the pump 8 is formed, and air is mixed by natural intake by the ejector device 7 by incorporating the above-described natural intake type ejector device 7 in the middle of the return pipe 33. The liquid (gas-liquid) is sucked into the second pump 8 and pressurized in the pump 8, and then supplied to the gas-liquid mixing device 10A through the mixer device 9. Yes, since the configuration other than this is the same as that of the adjustment tank water treatment system S1 of FIG. 2, the same reference numerals are given to the same members, and detailed descriptions thereof are 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.

  According to the adjustment tank water treatment system S2 of FIG. 7 having the above-described configuration, the gas and liquid mixture is not fed directly to the suction side 8A of the second pump 8, but the second pump 8 is mixed. Since it is fed to the suction side 8A, as a specific example of the second pump 8, for example, even if a non-volumetric centrifugal pump (spiral pump) that is currently most commonly used is adopted, In addition, it is possible to effectively prevent a reduction in the efficiency of gas-liquid mixing due to insufficient supply of gas-liquid from the centrifugal pump to the gas-liquid mixing apparatus 10A, and the gas-liquid mixing apparatus 10A can efficiently mix the gas and liquid. 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 the gas-liquid mixing apparatus 10B (not included in the present invention) , and FIG. 9 is a system configuration diagram of the adjustment 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 guided to the first taper channel 50, whereby the gas-liquid is further rotated in the first taper channel 50. And mix.

  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, the gas is introduced into the orifice channel 52, decompressed by the orifice channel 52, and discharged 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.

  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 in two stages of 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 the 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 apparatus 10C is installed on the upper surface of the water surface near the upstream of the aeration tank 2 as shown in FIG. 10, and as shown in FIG. 11, (1) a cylindrical sealed container 24, (2) A fluid introduction pipe 25 connected to the discharge side 8B of the second 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; and (3) the sealed container 24, a fluid discharge port 26 for discharging gas and liquid from the inside to the outside, (4) a discharge tube 27 attached to the fluid discharge port 26, and (5) a gas introduction tube 15 attached to the discharge tube 27. Composed.

  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 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 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, gas and liquid are mixed, and the amount of dissolved oxygen in the fluid can be further 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 Table 1 of 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 Table 2 in 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 centrifugal separation caused by vortices 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 Table 3 of FIG. From Table 3, according to this device, since the concentration of dissolved oxygen in the water tank has increased before all the tap water stored in the water tank has been processed in this device, the drainage discharge force from this device. 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.

The schematic block diagram of the waste water treatment equipment to which the gas-liquid mixing apparatus of 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 according to the present invention , where (a) is a cross-sectional view of the gas-liquid mixing device, (b) is a view as viewed from arrow B, and (c) is a line cc. It is sectional drawing. 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 a gas-liquid mixing apparatus (it is not included in this invention) . 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 concerns on this invention 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.

Explanation of symbols

S Wastewater treatment facilities S1, S2, S3, S4 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 Water intake conduit 12A, 12B Joint 13 Pipe 14 Throttle portion 15 Gas inlet tube 16 Motor 17 Water supply conduit 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 72A Return sludge outlet 73 Sludge return route 100 Control panel 101 Flow meter 90 Comparison nozzle structure 91 Hole

Claims (4)

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 to the outside ,
The fluid introduction pipe is provided at a central portion in the cylindrical axial direction of the sealed container in a state where the cylindrical sealed container is placed sideways, and a distal end of the fluid introduction pipe passes through a side surface of the cylindrical sealed container. Entered to the back of the sealed container, the tip of the fluid introduction pipe that has entered this back is provided as a fluid introduction port so as to open close to the inner bottom surface of the cylindrical sealed container ,
The fluid discharge port comprises a suction hole penetrating a plate-like member and a plurality of ejection holes,
The suction hole is located at the center of the plate-shaped member,
The plurality of ejection holes are located around the suction hole,
The gas-liquid introduced from the fluid introduction port of the fluid introduction pipe into the sealed container is diffused in a fan-shaped thin layer along the inner circular arc surface of the sealed container toward the left and right inner end surfaces of the sealed container. A thin layer vortex around the cylindrical axis of the container is formed,
By the thin layer vortex, a drawing vortex with a gas column extending from the inside of the closed container into the external gas-liquid through the central suction hole is formed,
The gas in the gas and liquid outside the sealed container is guided into the sealed container through the gas column, whereby the gas and liquid in the sealed container are easily discharged to the outside from the plurality of surrounding ejection holes. A gas-liquid mixing device. The gas-liquid mixing device according to claim 1 , wherein the suction hole has a diameter larger than that of the ejection hole. Gas-liquid mixing apparatus according to claim 1 or 2, characterized in that the discharge tube is attached to a fluid discharge side of the fluid discharge opening. The gas-liquid mixing device according to claim 3 , further comprising a gas introduction pipe communicating from the outside of the discharge cylinder to the fluid discharge side negative pressure portion of the fluid discharge port.

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