JP2010022961A - Water treatment apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water treatment apparatus and method which enables the economical and efficient detoxification of hardly decomposable compounds such as organofluorine compounds. <P>SOLUTION: In the water treatment apparatus, organofluorine compounds in inflow water can be decomposed and gasified by two step nanobubble treatment using the oxidizing power of nanobubbles, comprising nanobubble treatment by a first nanobubble generator 2 in an upstream decomposition portion water tank 42 and nanobubble treatment by a second nanobubble generator 86 in a downstream decomposition portion water tank 43, and the decomposed and gasified products can be adsorbed away by activated carbon 76-78. The gas as a decomposition product obtained by the decomposition of the organofluorine compounds using the oxidizing power of the nanobubbles is always removed from the water surface 25 by ventilation using a fan 17, thereby enabling making the decomposition more efficient. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention treats water containing a hardly decomposable organic or inorganic compound (for example, water containing a hardly decomposable organic fluorine compound such as PFOS (perfluorooctane sulfonic acid), PFOA (perfluorooctanoic acid)). The present invention relates to a water treatment apparatus and a water treatment method.

  Conventionally, methods for treating water containing refractory organic fluorine compounds such as PFOS and PFOA include (1) a combustion method that consumes fuel and promotes global warming, and (2) a high-pressure supercritical method. Existed. This conventional technique is suitable when the organic fluorine compound concentration is high and the amount of waste water is small. The specific amount of wastewater is suitable at most several tons per day.

  On the other hand, the organic fluorine compound concentration in the organic fluorine compound-containing wastewater discharged from the semiconductor factory is low at the ppb level, and the amount of wastewater is several tens to hundreds of tons per day, and the amount of wastewater is large.

  In addition, in the water treatment, the concentration of organic fluorine compounds in river water and lake water is actually lower than in the case of drainage, and the amount of water is actually larger.

  As with dioxins, environmental pollution of perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) as organic fluorine compounds is becoming a problem internationally.

  The organic fluorine compound is a chemically stable water-soluble substance. In particular, the organic fluorine compounds have excellent properties from the viewpoints of heat resistance and chemical resistance, and thus are widely used as industrial materials such as various surfactants and antireflection films in semiconductor production.

  However, since the organic fluorine compound is a chemically stable substance, microbial degradation is difficult. Therefore, since it is difficult to decompose microorganisms, it is a problem of environmental pollution because it exists in the environment for a long time when it is released into the environment. For example, perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) as the organic fluorine compounds are concerned about the influence on the ecosystem because the decomposition in the ecosystem does not proceed. That is, the above-mentioned perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are chemically stable, and therefore require a high temperature of about 1000 ° C. or higher for reliable thermal decomposition.

  On the other hand, PFOS and PFOA are extremely difficult to decompose by treatment with conventional microorganisms or conventional photocatalysts.

  By the way, the utilization method and apparatus of the nanobubble as a prior art are described in patent document 1 (Unexamined-Japanese-Patent No. 2004-121962). This prior art utilizes characteristics such as a reduction in buoyancy, an increase in surface area, an increase in surface activity, generation of a local high-pressure field, and a surface active action and a bactericidal action by realizing electrostatic polarization. More specifically, by interlinking them, various objects can be washed with high functionality and low environmental load by the adsorption function of dirt components, the high-speed washing function of the object surface, and the sterilization function. It discloses that purification can be performed.

  As another conventional technique, a method for generating nanobubbles is described in Patent Document 2 (Japanese Patent Laid-Open No. 2003-334548). In this conventional technique, in a liquid, (1) a step of cracking and gasifying a part of the liquid, (2) a step of applying ultrasonic waves in the liquid, or (3) a step of cracking and gasifying a part of the liquid And a process of applying ultrasonic waves.

  As another conventional technique, a waste liquid treatment apparatus using ozone microbubbles is described in Patent Document 3 (Japanese Patent Laid-Open No. 2004-321959). In this prior art, ozone gas generated from the ozone generator and waste liquid extracted from the lower part of the treatment tank are supplied to the microbubble generator via a pressure pump. It also discloses that the generated ozone microbubbles are vented into the waste liquid in the treatment tank through the opening of the gas blowing pipe.

  By the way, the concentration of organic fluorine compounds in organic fluorine compound-containing wastewater, river water, and lake water discharged from each factory is low and exists in large quantities.

  As mentioned above, there are (1) combustion treatment method that consumes fuel and promotes global warming, and (2) high-pressure supercritical treatment technology as conventional technologies. However, in a method corresponding to the case of high concentration and a small amount of water, when processing with these conventional techniques, there is a problem that the running cost cannot be kept low and cannot be economically processed. In addition, these conventional technologies (1) a combustion method that consumes fuel and promotes global warming, and (2) a high-pressure supercritical method have high construction costs.

  In addition, there is an activated carbon adsorption method different from the above (1) and (2) in wastewater treatment and water treatment, but activated carbon adsorbs all organic matter and breakthrough if there is organic matter in the treated water. However, there is also a problem that the activated carbon needs to be replaced frequently. That is, there is a problem that the running cost related to replacement of activated carbon is high.

  Moreover, as a general knowledge, the bond between carbon and fluorine, which is a chemical structural formula in organic fluorine compounds, is stable and does not decompose even in strong acids, so it is released into the environment and travels around the world. It has been concentrated in all living organisms around the world. For example, organic fluorine compounds have been detected in polar bears, seals, and whales, which has become a problem as an international environmental pollution.

In this way, in order to avoid bioconcentration of organic fluorine compounds including humans, which is an international environmental problem, there is a processing technology that can economically and highly efficiently detoxify refractory compounds such as organic fluorine compounds. There is a problem that does not.
JP 2004-121962 A JP 2003-334548 A JP 2004-321959 A

  Therefore, an object of the present invention is to provide a water treatment apparatus and a water treatment method capable of economically and efficiently detoxifying a hardly decomposable compound such as an organic fluorine compound.

In order to solve the above problems, the water treatment apparatus of the present invention includes a water tank into which water containing a hardly decomposable compound is introduced,
A gas-liquid mixed gas shearing nanobubble generator for discharging nanobubbles into the hardly decomposable compound-containing water in the water tank;
The water tank includes a gas removal unit that removes a decomposition product of the hardly decomposable compound that has been decomposed and gasified by oxidizing power of radicals of the nanobubbles.

  According to the water treatment apparatus of the present invention, the nanobubbles are discharged from the gas-liquid mixed gas shearing nanobubble generator into the hardly decomposable compound-containing water introduced into the water tank, so that the oxidizing power by radicals of the nanobubbles is increased. By utilizing this, it is possible to decompose a strong bond of a hardly decomposable compound and to gasify and remove a low molecular decomposition product.

  In one embodiment, the hardly decomposable compound is an organic compound.

  According to the water treatment apparatus of this embodiment, it is possible to decompose strong bonds of hardly decomposable organic compounds and gasify and remove low molecular decomposition products by utilizing the oxidizing power of radicals possessed by nanobubbles. .

In one embodiment of the water treatment apparatus, the hardly decomposable compound is an organic fluorine compound,
A pre-stage water tank into which the organic fluorine compound-containing water is introduced;
A first nanobubble generator of a gas-liquid mixed gas shearing system that discharges nanobubbles to the organic fluorine compound-containing water in the front stage water tank;
A rear water tank into which treated water from the front water tank is introduced;
A second nanobubble generator of a gas-liquid mixed gas shearing system that discharges nanobubbles to the organic fluorine compound-containing water in the rear water tank;
A gas removal unit that adsorbs and removes the gasified decomposition product of the organic fluorine compound decomposed by the oxidizing power of radicals of the nanobubbles in the rear water tank.

  According to the water treatment apparatus of this embodiment, the organic fluorine compound in the water containing the organic fluorine compound in which carbon and fluorine are firmly bonded can be reliably obtained by the two-stage nanobubble treatment of the front water tank and the rear water tank. It can be decomposed and adsorbed and removed.

  In one embodiment, the organic fluorine compound-containing water contains at least one of PFOS (perfluorooctane sulfonic acid) or PFOA (perfluorooctanoic acid).

  According to the water treatment apparatus of this embodiment, the non-decomposable organic fluorine compound such as PFOS (perfluorooctane sulfonic acid) and PFOA (perfluorooctanoic acid) in which carbon and fluorine are firmly bonded is decomposed and harmless. Can be

  Moreover, in the water treatment apparatus of one Embodiment, the said nano bubble generator has a three-stage gas-liquid mixed-gas shearing part.

  According to the water treatment apparatus of this embodiment, since the nanobubble generator is composed of a three-stage gas-liquid mixed gas shearing section, a large amount of nanobubbles can be produced by further shearing the microbubbles.

Moreover, in the water treatment apparatus of one embodiment, a calcium ion elution part that is disposed on the front stage water tank and nanobubbles from the front stage water tank are introduced to cause calcium ions to drip into the front stage water tank,
A settling tank in which treated water is introduced from the front water tank and the treated water is introduced into the rear water tank;
And a gas adsorbing part that is disposed on the rear water tank and that adsorbs a gas generated by decomposing the organic fluorine compound with the nanobubbles using an adsorbent.

  According to the water treatment apparatus of this embodiment, the fluoride ions and sulfate ions contained in the decomposition product decomposed by the nanobubbles in the preceding stage water tank are reacted with the calcium ions dropped from the calcium ion elution portion to fluorinate. Calcium and calcium sulfate can be precipitated and removed in the next settling tank. Moreover, the low-molecular decomposition products decomposed and gasified by the nanobubbles in the latter-stage water tank can be adsorbed and removed by the gas adsorption unit.

  Moreover, in the water treatment apparatus of one Embodiment, the air supply part which supplies air between the said front part water tank and the said calcium ion elution part was provided.

  According to the water treatment device of this embodiment, saturated steam generated near the liquid surface of the front-stage water tank by supplying air from the air supply section between the front-stage water tank and the calcium ion elution section. It is possible to eliminate the saturation state by always supplying fresh air to (saturated steam generated by decomposition). Thereby, the decomposition | disassembly by the said nano bubble can be accelerated | stimulated.

  Moreover, in the water treatment apparatus of one Embodiment, the adsorbent of the said gas adsorption part is activated carbon.

  According to the water treatment apparatus of this embodiment, the gas generated by the decomposition by the nanobubbles in the rear water tank can be efficiently adsorbed with the activated carbon as the adsorbent.

Moreover, in the water treatment apparatus of one embodiment, the nanobubble generator is
A gas-liquid mixing circulation pump having a first gas shearing part capable of introducing gas by an electric needle valve;
A second gas shearing part into which microbubbles are introduced from the first gas shearing part;
A third gas shearing part into which nanobubbles are introduced from the second gas shearing part.

  According to the water treatment device of this embodiment, a part of the microbubbles manufactured in the first gas shearing part can be turned into nanobubbles in the second gas shearing part, and finally a large amount of nanobubbles are produced in the third gas shearing part. Can be manufactured.

  Moreover, in the water treatment apparatus of one Embodiment, air is introduce | transduced into the said 1st gas shear part from the said electric needle valve at 1.2 liter / min or less.

  According to the water treatment apparatus of this embodiment, a large amount of nanobubbles can be produced from the third gas shearing portion by setting the amount of air introduced into the first gas shearing portion to 1.2 liters / minute or less. . If the amount of air introduced into the first gas shearing portion exceeds 1.2 liters / minute, the proportion of microbubbles discharged from the third gas shearing portion increases as a result.

  Moreover, in the water treatment apparatus of one Embodiment, the said 1st gas shearing part is an ellipse or a perfect circle shape, and the 2 or more groove | channel is formed in the inside.

  According to the water treatment apparatus of this embodiment, the air shearing by the first gas shearing portion can be rationally and stably performed, and a large amount of microbubbles can be produced.

  Moreover, in the water treatment apparatus of one Embodiment, the depth of the said groove | channel is 0.3 mm-0.6 mm, and a groove width is less than 0.8 mm.

  According to the water treatment apparatus of this embodiment, the air shearing by the first gas shearing portion can be rationally and stably performed, and a large amount of microbubbles can be produced.

  Moreover, in the water treatment apparatus of one Embodiment, the said gas-liquid mixing circulation pump has the internal diameter of discharge piping smaller than the internal diameter of suction piping.

  According to the water treatment apparatus of this embodiment, the air shearing by the first gas shearing portion can be rationally and stably performed, and a large amount of microbubbles can be produced.

  Moreover, in the water treatment apparatus of one Embodiment, the said gas-liquid mixing circulating pump starts gas intake after the pump output of the said gas-liquid mixing circulating pump reaches the maximum value.

  According to the water treatment apparatus of this embodiment, damage due to cavitation of the gas-liquid mixing circulation pump can be prevented. That is, if the pump is operated in a state where gas (air) is present in the liquid, cavitation may occur and the pump may be damaged.

  Moreover, in the water treatment apparatus of one Embodiment, the said gas-liquid mixing circulation pump starts gas intake after 60 second or more has passed since the operation start.

  According to the water treatment apparatus of this embodiment, damage due to cavitation of the gas-liquid mixing circulation pump can be prevented by starting gas uptake after 60 seconds or more have elapsed from the start of operation.

  Moreover, in the water treatment apparatus of one embodiment, the gas inflow pipe for flowing gas from the electric needle valve to the first gas shearing portion has an incident angle of 18 ° with respect to the side surface of the microbubble generating portion of the first gas shearing portion. It is arranged to become.

  According to the water treatment apparatus of this embodiment, the air shearing by the first gas shearing portion can be rationally and stably performed, and a large amount of microbubbles can be produced.

  Moreover, in the water treatment apparatus of one Embodiment, the thickness of the material which comprises the said 1st gas shearing part was 6 mm to 12 mm.

  According to the water treatment apparatus of this embodiment, by setting the material thickness of the first gas shearing part to 6 mm to 12 mm, kinetic energy is not released to the outside, and as a result, shearing of air is rational. In addition, it is possible to stably produce a large amount of microbubbles.

  Moreover, in the water treatment apparatus of one Embodiment, the gas supplied to the said nano bubble generator was made into ozone.

  According to the water treatment apparatus of this embodiment, since the gas supplied to the nanobubble generator is ozone, ozone nanobubbles can be produced, and refractory organic fluorine compounds can be oxidatively decomposed with a strong oxidizing action.

  In one embodiment, the gas supplied to the nanobubble generator is oxygen gas.

  According to the water treatment apparatus of this embodiment, the nanobubble generator can generate nanobubbles by oxygen gas that has an oxidizing power than air, and can oxidize and decompose hardly decomposable organic fluorine compounds by oxidation action with oxygen gas nanobubbles. .

Moreover, in the water treatment method of one embodiment, nanobubbles are discharged and mixed in the hardly decomposable compound-containing water,
Utilizing the oxidizing power of the radicals possessed by the nanobubbles, the strong bonds of the hardly decomposable compound are decomposed, and the decomposition products by the decomposition are gasified and removed.

  According to the water treatment method of this embodiment, the strong bond of a hardly decomposable compound can be decomposed using the oxidizing power of radicals possessed by nanobubbles, and the low molecular decomposition product can be gasified and removed.

  In one embodiment of the water treatment method, the hardly decomposable compound is an organic compound.

  According to the water treatment method of this embodiment, the strong bond of the hardly decomposable organic compound can be decomposed using the oxidizing power of radicals possessed by the nanobubbles, and the low molecular decomposition product can be gasified and removed.

In one embodiment of the water treatment method, the hardly decomposable compound is an organic fluorine compound,
Nanobubbles are discharged and mixed into the organic fluorine compound-containing water, and the strong bond between carbon and fluorine of the organic fluorine compound is decomposed using the oxidizing power of the radicals of the nanobubbles, A first process for gasification and removal;
The nanobubbles are discharged and mixed in the treated water after the first treatment, and the strong bond between carbon and fluorine of the organic fluorine compound is decomposed using the oxidizing power of the radicals of the nanobubbles. A second treatment for removing the decomposition product by gasification is performed.

  According to the water treatment method of this embodiment, the organic fluorine compound in the organic fluorine compound-containing water in which carbon and fluorine are firmly bonded is decomposed by the decomposition treatment using the first and second nanobubbles. Can be detoxified.

  Moreover, in the water treatment method of one embodiment, in the first treatment, sulfate ions of the decomposition product are reacted with calcium ions and removed.

  According to the water treatment method of this embodiment, the sulfate ions of the decomposition product can be reacted with calcium ions to be removed as calcium sulfate.

  In one embodiment of the water treatment method, a water droplet containing nanobubbles is dropped on a calcium carbonate mineral to elute the calcium ions.

  According to the water treatment method of this embodiment, a small amount of calcium ions can be eluted from the calcium carbonate mineral with the oxidizing power of nanobubbles.

  Moreover, in the water treatment method of one embodiment, water droplets containing nanobubbles are dropped on the calcium carbonate mineral, and the gasified low-molecular organic fluorine compound is further decomposed into low molecules on the surface of the calcium carbonate mineral.

  According to the water treatment method of this embodiment, a low molecular organic fluorine compound such as PFC (perfluorocarbon) can be further decomposed into low molecules on the surface of the calcium carbonate mineral and rendered harmless.

  In one embodiment of the water treatment method, calcium ions eluted from the calcium carbonate mineral are reacted with fluorine ions generated by decomposition of the low molecular organic fluorine compound to form a precipitate of calcium fluoride. .

  According to the water treatment method of this embodiment, fluorine ions produced by decomposition of the low molecular organic fluorine compound are reacted with calcium ions eluted from the calcium carbonate mineral to render them harmless as calcium fluoride precipitates. it can.

  In one embodiment of the water treatment method, calcium fluoride eluted from the calcium carbonate mineral is reacted with fluorine ions generated by the decomposition of the low-molecular organic fluorine compound in the presence of nanobubbles to produce calcium fluoride. The floc of calcium fluoride is precipitated in a settling tank.

  According to the water treatment method of this embodiment, fluorine ions generated by decomposing the low-molecular-weight organic fluorine compound in the presence of nanobubbles are reacted with the calcium ions to form calcium fluoride flocs and precipitate. It can be detoxified as a precipitate in the tank.

  According to the water treatment apparatus of the present invention, the nanobubbles are discharged from the gas-liquid mixed gas shearing nanobubble generator into the hardly decomposable compound-containing water introduced into the water tank, so that the oxidizing power by radicals of the nanobubbles is increased. By utilizing this, it is possible to decompose a strong bond of a hardly decomposable compound and to gasify and remove a low molecular decomposition product.

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

(First embodiment)
Drawing 1 is a figure showing typically a 1st embodiment of a water treatment equipment of the present invention.

  In FIG. 1, reference numeral 1 denotes an inflow pipe, and the organic fluorine compound-containing water flows into the pre-stage decomposition section water tank 42 through the inflow pipe 1. Examples of the organic fluorine compound-containing water include organic fluorine compound-containing wastewater discharged from each factory, general river water and general lake water containing a small amount of organic fluorine compound, and the like.

  The nanobubble treatment apparatus 3 included in the water treatment apparatus of the first embodiment is roughly composed of a calcium ion elution part 21 that forms the upper part of the nanobubble treatment apparatus 3, a decomposition product gas adsorption part 66, a lower front decomposition part water tank 42, and a rear decomposition. It consists of a partial water tank 43.

  And when inflow water is pumped with a pump etc., the water stream 15 is generated in the front | former decomposition | disassembly part water tank 42, this water stream 15 merges with the nano bubble stream 13 discharged from the 1st nano bubble generator 2, and a front | former stage decomposition | disassembly Since the inclined wall 40 is installed in the lower part of the partial water tank 42, the flow of water for stirring the inside of the preceding decomposition part water tank 42 is obtained.

  A first nanobubble generator 2 and a second nanobubble generator 86 are installed outside the front-stage decomposition unit water tank 42 and the rear-stage decomposition unit water tank 43 that form the lower part of the nanobubble treatment apparatus 3. A fan 17 for constantly taking in fresh air is installed at the lower part of the calcium ion elution part 21 that forms the upper part of the nanobubble treatment apparatus 3.

  The calcium ion elution part 21 is filled with calcium carbonate mineral as a calcium ion supply source in three stages as a lower calcium carbonate mineral 32, an intermediate calcium carbonate mineral 33, and an upper calcium carbonate mineral 34. An upper outlet 24, an intermediate outlet 23, and a lower outlet 22 for taking out and putting in these calcium carbonate minerals 32, 33, and 34 are installed in the upper calcium ion elution portion 21. The lower calcium carbonate mineral 32, the intermediate calcium carbonate mineral 33, and the upper calcium carbonate mineral 34 are accommodated in the lower accommodation container 29, the intermediate accommodation container 30, and the upper accommodation container 31, which are the respective accommodation containers. The storage containers 29, 30, and 31 are respectively installed on the lower fixed hole base 26, the intermediate part hole base 27, and the upper hole base 28.

  Since each container 29-31 and the perforated bases 26-28 have innumerable holes, the mixed gas of the primary decomposition product gas 38 and the fresh air flow 39 smoothly flows into the calcium ion elution part 21. Will be introduced into the duct 47. Then, the primary decomposition product gas 38 is introduced into the decomposition gas adsorption unit 66.

  Further, on the upper part of the calcium ion elution part 21, a sprinkling water pipe 46 to which a sprinkling nozzle 45 is attached is installed, and by operating the sprinkling pump 80 for washing water containing nanobubbles in the latter decomposition part water tank 43, the calcium ion Water is sprayed as nanobubble-containing water drops 82 in the elution part 21. The end of the sprinkling water pipe 46 is fixed in the elution part 21 with a flange 44.

  Since nanobubbles have an oxidizing power and a detergency as a characteristic, calcium ions are eluted from calcium carbonate minerals 32, 33, and 34 installed and packed in three stages in the calcium ion elution part 21, and the pre-stage decomposition part It is dripped in the water tank 42. The calcium ions react with sulfate ions generated by the decomposition of PFOS (perfluorooctane sulfonic acid) to form calcium sulfate floc 53. The calcium sulfate floc 53 formed in the front-stage decomposition unit water tank 42 flows into the precipitation tank 51 from the partition plate 50 together with the water flow 65, and the supernatant and the precipitate are separated into solid and liquid. It flows into the decomposition part water tank 43.

  On the other hand, the calcium sulfate floc 53 settles on the lower part of the sedimentation tank 51 by its specific gravity and by the inclination of the sedimentation tank inclined wall 64, and is drained outside the system by opening the drain valve 52 after a certain time. .

  On the other hand, since nanobubbles have an oxidizing power and a cleaning power as characteristics, PFC (perfluorocarbon) as a low molecular weight organic fluorine compound is further decomposed to partially decompose into fluorine ions. This fluoride ion reacts with the eluted calcium ion to form a precipitate of calcium fluoride. Thereby, PFC processing is also possible.

  The formed calcium fluoride precipitate is precipitated in the precipitation tank 51 and discharged from the drain valve 52 in the same manner as the calcium sulfate precipitate. In the sedimentation tank 51, the water to be treated as a supernatant liquid that has been subjected to solid-liquid separation and from which calcium sulfate and calcium fluoride have been removed flows into the rear decomposition unit water tank 43. A second nanobubble generator 86 is installed in the latter decomposition unit water tank 43. The second nanobubble generator 86 discharges nanobubbles to the water to be treated to form nanobubble-containing water.

  Next, the processing state in the front | former stage decomposition | disassembly part water tank 42 and the back | latter stage decomposition part water tank 43 is demonstrated in detail. PFOS, PFOA, etc. in the organic fluorine compound-containing water introduced into the pre-stage decomposition section water tank 42 are oxidatively decomposed by nanobubbles discharged from the first nanobubble generator 2. These PFOS, PFOA, and the like are chemically stable substances, and the structure of carbon and fluorine is considered to be a compound that cannot be decomposed by conventional methods.

  However, it has been found that the nanobubbles can be decomposed over time by the oxidizing action of the radicals generated by the nanobubbles. Since radicals are usually highly reactive, as soon as they are generated, they undergo an oxidation reaction with other atoms and molecules to become stable molecules and ions.

  Next, the mechanism of the first nanobubble generator 2 will be described in detail.

  The first nanobubble generator 2 includes a gas-liquid mixing / circulation pump 5, a first gas shearing unit 6, a second gas shearing unit 8, a third gas shearing unit 12, an electric needle valve 11 and pipes 7, 9, 10 and a suction pipe 4. Nanobubbles are generally manufactured in a third stage through a first stage and a second stage.

  This first stage will be briefly described. In the first gas shearing section 6, the pressure is controlled hydrodynamically, the gas is sucked from the negative pressure forming part, and the fluid is moved at a high speed to form the negative pressure part, and microbubbles are generated. To make it easier to understand, the first step is to produce microbubble cloudy water by effectively self-sufficiency, mixing, dissolving and pumping water and air.

  Next, the second stage will be briefly described. In the 2nd gas shear part 8 and the 3rd gas shear part 12, it is made to make high-speed fluid motion, a negative pressure part is formed, and a microbubble is generated. In addition, microbubble cloudy water is introduced into the second gas shearing portion 8 and the third gas shearing portion 12 from the first gas shearing portion 6 through the water pipe 7 and sheared as a fluid motion to generate nanobubbles from the microbubbles. It will be.

  Further, the first stage and the second stage will be described in more detail.

(First stage)
The gas-liquid mixing circulation pump 5 used in the first nanobubble generator 2 is a high-lift pump having a lift of 40 m or higher (that is, a high pressure of 4 kg / cm ² ). Here, the gas-liquid mixing circulation pump 5 having the first gas shearing section 6 is a high-lift pump, and it is necessary to select a two-pole pump having a stable torque. There are two-pole and four-pole pumps, and the torque of the 2-pole pump is more stable.

  Further, the gas-liquid mixing circulation pump 5 needs to control the pressure, and the rotational speed of this high-lift pump is set to a desired pressure by a rotational speed controller (generally called an inverter). By setting the pressure to this purpose, microbubbles with a combined bubble size can be manufactured.

  Here, the mechanism of microbubble generation in the gas-liquid mixing circulation pump 5 having the first gas shearing part 6 will be described. In order to generate microbubbles in the first gas shearing section 6, a mixed-phase swirling flow of liquid and gas is generated, and a gas cavity that is swirled at a high speed is formed at the center of the first gas shearing section 6. Next, the hollow portion is thinned into a tornado shape with pressure to generate a rotating shear flow that swirls at a higher speed. Air as a gas is automatically supplied to the cavity using a negative pressure (negative pressure), and the mixed phase flow is rotated while being cut and pulverized. Note that ozone, carbon dioxide gas, nitrogen gas, and oxygen gas may be used instead of the gas, but in the present invention, it is simply air. Other gases may be selected depending on the purpose.

  The above air cutting and pulverization occurs due to the difference in swirling speed between the inner and outer gas-liquid two-phase fluids near the outlet of the apparatus. The rotation speed at that time is 500 to 600 rotations / second. That is, in the first gas shearing section 6, the pressure is hydrodynamically controlled so that the gas is sucked from the negative pressure forming portion and is moved at high speed by the high lift pump to form the negative pressure portion. Contain microbubbles. To explain more easily and simply, the first step is to produce micro-bubble cloudy water by effectively self-suppliing, mixing, dissolving and pumping water and air with a high head pump.

  The operation of the gas-liquid mixing circulation pump 5 is set and controlled by a signal from a sequencer (not shown). In addition, the internal shape of the first gas shearing portion 6 is an oval as an example, but the shape that produces the maximum effect is a perfect circle, and in order to further reduce the internal friction, a mirror finish is used here. Further, a groove having a groove depth of 0.3 mm to 0.6 mm and a groove width of 0.8 mm or less is provided in the first gas shearing part 6 in order to control the swirling turbulent flow of the fluid.

(Second stage)
Next, the second stage in the first nanobubble generator 2 will be described. In the second stage, the microbubbles generated by the gas-liquid mixing circulation pump 5 having the first gas shearing part 6 are pumped to the second gas shearing part 8 through a water pipe. At this time, in the second gas shearing portion 8 and the third gas shearing portion 12, after the first stage described above, the pipe size is further reduced and the fluid is moved at high speed to make the gas cavity portion narrower in a tornado shape. Generate a rotating shear flow that swirls at a higher speed. As a result, nanobubbles are generated from the microbubbles, and at the same time, an extremely high temperature extreme reaction field is formed. Here, the reason why the second gas shearing part 8 and the third gas shearing part 12 are configured is that, in order to generate a larger amount of nanobubbles, the three-stage gas than the one-stage gas shearing part is configured. This is because the amount of nanobubble generation can be increased by configuring the shearing portion.

  When the above-described ultra-high temperature extreme reaction field is formed, a local high-temperature and high-pressure state is created, unstable free radicals (also called radicals) are generated, and heat is generated at the same time as it exhibits an oxidizing action. The second gas shearing portion 8 and the third gas shearing portion 12 are generally made of stainless steel, and the shape thereof is an ellipse, preferably a perfect circle. Moreover, although the small hole is opened in the 2nd gas shearing part 8 and the 3rd gas shearing part 12, the discharge port diameters are 4 mm-9 mm optimal.

  Next, the high speed fluid motion in the first stage will be described. That is, in order to generate microbubbles in the first gas shearing section 6, first, as “high-speed fluid motion”, a wing called an impeller of a pump is rotated at an ultrahigh speed, and a mixed phase swirl flow of liquid and gas And a gas cavity is formed in the central portion of the first gas shearing portion 6 to rotate at high speed. Next, the hollow portion is thinned into a tornado shape with pressure to generate a rotating shear flow that swirls at a higher speed. Air (gas, ozone, carbon dioxide, nitrogen gas, oxygen gas in some cases) as a gas is self-supplied in the cavity. Furthermore, the multiphase flow is rotated while cutting and crushing. This cutting and pulverization occurs due to the difference in the swirling speed of the gas-liquid two-phase fluid inside and outside the vicinity of the apparatus outlet. It has been found that the rotational speed is 500 to 600 revolutions / second.

  Further, if the metal constituting the first gas shearing portion 6 is thin, vibration is generated by operating the gas-liquid mixing circulation pump 5, and fluid kinetic energy propagates outside as vibration and escapes. This reduces the required high velocity flow motion, i.e., high speed swirl and shear energy. For this reason, the thickness of the metal which comprises the 1st gas shearing part 6 has the preferable range of 6 mm-12 mm.

  Next, “shearing as a fluid motion” will be described. That is, when the microbubbles generated by the gas-liquid mixing circulation pump 5 having the first gas shearing part 6 are pumped to the second gas shearing part 8 and the third gas shearing part 12 through the water pipe, the second gas shearing part. In 8 and the third gas shearing part 12, after the first stage, the pipe size is further reduced and the fluid is moved at high speed to make the gas cavity narrower in a tornado shape and rotate at a higher rotational speed. generate.

  Next, the “negative pressure forming portion” will be described. This negative pressure forming portion is generated by the difference in the swirling speed of the gas-liquid two-phase fluid inside and outside in the vicinity of the apparatus outlet. As described above, the rotation speed is 500 to 600 rotations / second. Next, the “negative pressure part” will be described. The “negative pressure part” means a region in the gas and liquid mixture where the pressure is smaller than the surroundings.

  The above is the mechanism of operation in the first nanobubble generator 2. The operation mechanism of the second nanobubble generator 86 is exactly the same as the operation mechanism of the first nanobubble generator 2.

  In addition, the set of the gas-liquid mixing circulation pump 5, the 1st gas shearing part 6, the 2nd gas shearing part 8, and the 3rd gas shearing part 12 which comprises the said 1st nanobubble generator 2 fundamentally is marketed. Can be used, but the manufacturer is not limited. Here, as a specific example, a product manufactured by Kyowa Kikai Co., Ltd. (specific product name Babidas HYK type) was adopted.

  Here, four types of bubbles will be described.

  (1) A normal bubble (bubble) rises in the water and finally disappears by popping on the surface.

  (2) Microbubbles have a bubble diameter of 10 to several tens of microns (μm) at the time of generation, and become micronanobubbles by contraction movement after generation.

  (3) Micro-nano bubbles are bubbles having a diameter of about 10 μm to several 100 nm.

  (4) Nanobubbles are bubbles having a diameter of several hundred nm or less.

  Next, as described above, the first nanobubble generator 2 discharges the nanobubbles into the upstream decomposition unit water tank 42 to form the nanobubble flow 13. The formed nanobubble flow 13 and the water flow 15 which is the discharge water from the pump or the like merge to form a large water flow, and the inside of the front decomposition unit water tank 42 is agitated.

Then, the inside of the pre-stage decomposition unit water tank 42 is agitated, whereby the organic fluorine compounds (PFOS, PFOA, etc.) in the water to be treated are decomposed by the oxidation action of the nanobubbles, and low molecular organic fluorine compounds (CF ₃ (CF ₂₎ ) becomes ₃ H, etc. many). As a result, the low molecular weight organic fluorine compound (CF ₃ (CF ₂ ) ₃ H and many others) is gasified and rises to the vicinity of the water surface 25 of the decomposition unit water tank 42.

In addition, if the state of the gas phase near the water surface 25 of the front decomposition unit water tank 42 is a saturated vapor state (a state in which both phases of gas and liquid coexist or a state in which saturated vapor exists), an organic fluorine compound (PFOS) in the water to be treated , PFOA, etc.) are not easily decomposed even in the presence of nanobubbles, and a phenomenon occurs that it is difficult to change to a low molecular weight organic fluorine compound (such as CF ₃ (CF ₂ ) ₃ H). This phenomenon was found by experiments conducted several times. That is, the decomposition product gas 38 is hardly generated. This is a rare phenomenon but could be confirmed by experiments.

On the contrary, by the operation of the fan 17, fresh air is continuously introduced from the suction port 16 via the discharge duct 18 and the flange portion 19, and the state of the gas phase near the water surface 25 of the front-stage decomposition section water tank 42 is changed to the front-stage decomposition. If it is not in a saturated vapor state (a state in which both phases of gas and liquid coexist) near the water surface 25 of the partial water tank 42 (that is, a state in which ventilation is performed with fresh air), the decomposed gas 38 is often generated. That is, the organic fluorine compound (PFOS, PFOA, etc.) in the water to be treated is oxidized and decomposed in the presence of the nanobubbles to be changed to low molecular weight organic fluorine compounds (CF ₃ (CF ₂ ) ₃ H, etc.). A large number of low-molecular organic fluorine compounds such as CF ₃ (CF ₂ ) ₃ H are continuously gasified to become a primary decomposition product gas 38.

Further, on the upper calcium carbonate mineral 34, the intermediate calcium carbonate mineral 33, and the lower calcium carbonate mineral 32, which are calcium carbonate minerals, a low-molecular organic fluorine compound (CF ₃ (CF ₂ ) ₃ ) in the presence of nanobubbles. H, etc.) are oxidatively decomposed by the oxidizing action of radicals of nanobubbles and partially become fluorine ions. The fluorine ions react with calcium ions eluted from the calcium carbonate minerals 32, 33, and 34 to become calcium fluoride. This phenomenon of becoming calcium fluoride is a reaction that occurs also in the water tank of the pre-stage decomposition section water tank 42.

  Further, a second nanobubble generator 86 is installed in the rear decomposition unit water tank 43, and nanobubbles are discharged into the water to be treated to form a nanobubble flow 63, and nanobubble-containing water is produced. The second nanobubble generator 86 has the same structure as that of the first nanobubble generator 2 described above, and the gas-liquid mixing circulation pump 55, the first gas shearing part 56, the second gas shearing part 58, and the third gas shearing part. 62, an electric needle valve 61, pipes 57, 59, 60 for connecting them, and a suction pipe 54.

  Next, the situation of the rear decomposition unit water tank 43 will be described in detail. Trace amounts of PFOS, PFOA, etc. in the organic fluorine compound-containing water remaining in the treated water introduced into the post-stage decomposition section water tank 43 from the pre-stage decomposition section water tank 42 are discharged from the second nanobubble generator 86. It is oxidatively decomposed by nanobubbles. These PFOS, PFOA, and the like are chemically stable substances, and the structure of carbon and fluorine is considered to be a compound that cannot be decomposed by conventional methods.

  However, it has been found that even such a hardly decomposable compound can be decomposed with nanobubbles over time due to the oxidizing action of radicals generated by nanobubbles. Since radicals are usually highly reactive, as soon as they are generated, they undergo an oxidation reaction with other atoms and molecules to become stable molecules and ions. Therefore, the trace amount PFOS, PFOA, and the like in the rear decomposition unit water tank 43 are also oxidatively decomposed by the nanobubbles discharged from the second nanobubble generator 86 to generate the secondary decomposition product gas 85. The generated secondary decomposition product gas 85 merges with the primary decomposition product gas 38 introduced from the duct 47, so that the lower fixing hole base 70, the intermediate fixing hole base 71, and the upper fixing hole base 72. Adsorption treatment is performed in three stages on the lower activated carbon 76 in the lower activated carbon container 73 installed above, the lower activated carbon 76 in the intermediate activated carbon container 74, and the upper activated carbon 78 in the upper activated carbon container 75. Become. Then, the generated secondary decomposition product gas 85 is reliably decomposed and discharged from the exhaust chimney 35 as the processing gas 84.

  As described above, according to this embodiment, the organic fluorine compound is decomposed in two stages in the liquid by using the oxidizing power of the nanobubble in the first decomposition unit water tank 42 and the second decomposition unit water tank 43. A compound can be decomposed more reliably, and a decomposed product with a reduced number of carbon atoms can be gasified. Further, the decomposition can be made more efficient by constantly removing the gas as a decomposition product obtained by decomposing the organic fluorine compound using the oxidizing power of nanobubbles from the surface of the liquid phase (water surface) by blowing with the fan 17. I was able to. In addition, sulfate ions as decomposition products in the liquid phase can be reacted with calcium ions to precipitate and remove calcium sulfate floc 53, and various gases as decomposition products can be efficiently adsorbed and removed by activated carbon 76-78. it can. Moreover, in this embodiment, when processing a very small amount of sulfate ions, water containing nanobubbles is sprayed from the water spray nozzle 45 to the calcium carbonate minerals 32 to 34 so that calcium ions are efficiently eluted from the calcium carbonate minerals, and sulfate ions and It is effectively used for the reaction.

  As described above, the lower activated carbon 76, the intermediate activated carbon 77, and the upper activated carbon 78 are accommodated and installed in the lower activated carbon accommodating container 73, the intermediate activated carbon accommodating container 74, and the upper activated carbon accommodating container 75, which are the respective accommodating containers. Yes. Here, as a specific example of the lower activated carbon 76, the intermediate activated carbon 77, and the upper activated carbon 78, spherical activated carbon Kuraray Coal (trade name) manufactured by Kuraray Chemical Co., Ltd. was employed.

  The lower activated carbon storage container 73, the intermediate activated carbon storage container 74, and the upper activated carbon storage container 75, which are the respective storage containers, are the lower fixed hole base 70 and the intermediate fixed hole base 71 that are the respective fixed hole bases. The upper fixing hole base 72 is installed. In each of the fixed hole bases 70 to 72, the gas generated in the lower part of each of the fixed hole bases 70 to 72 passes through each of the fixed hole bases 70 to 72 and is easily adsorbed by a large number of activated carbons 76 to 78 in the upper part. Structure. That is, each activated carbon storage container 73 to 75 and each fixed hole base 70 to 72 have a large number of small holes so that the generated gas efficiently contacts each activated carbon 76 to 78.

  The activated carbons 76, 77, and 78 whose breakthrough state, that is, the lifespan, can be easily made from the lower outlet 67, the intermediate outlet 68, and the upper outlet 69 that are the respective outlets together with the respective containers 73, 74, and 75. To be replaced with new activated carbon. The lower outlet 67, the intermediate outlet 68, and the upper outlet 69 have a structure in which a flange lid is fastened with a bolt. By loosening the bolt and removing the flange lid, the activated carbon containing containers 73 to 75 can be easily made. It can be taken out. The used activated carbon is brought into a cement factory and is effectively used as fuel sludge.

  In the above embodiment, the hardly decomposable compound-containing water to be treated water is an organic fluorine compound-containing water containing PFOS, PFOA, etc., but may be other organic compound-containing water or inorganic compound-containing water.

(Second embodiment)
Next, FIG. 2 shows a second embodiment of the water treatment apparatus of the present invention. The water treatment apparatus according to the second embodiment shown in FIG. 2 is different from the first embodiment described above only in that the gas automatically sucked into the first nanobubble generator 2 is replaced with air to make ozone gas. However, this is different from the first embodiment described above. Therefore, in the second embodiment, the same parts as those in the first embodiment described above are denoted by the same reference numerals and detailed description thereof will be omitted, and parts different from those in the first embodiment will be described.

  In this second embodiment, since ozone gas has an oxidizing power rather than air in which the gas automatically sucked into the first nanobubble generator 2 is ozone gas, ozone nanobubbles are discharged from the first nanobubble generator 2. The object to be treated in the water to be treated can be oxidatively decomposed. This ozone nanobubble can maintain the oxidizing power for a long period of one month or more in water. On the other hand, in other ozone bubbles, the duration of staying in water is shorter. According to the second embodiment, ozone having an oxidizing power is further converted into nanobubbles having a oxidizing power by radicals, and the oxidizing power is synergistically enhanced to oxidatively decompose the object to be treated in the water to be treated. can do.

(Third embodiment)
Next, FIG. 3 shows a third embodiment of the water treatment apparatus of the present invention. The third embodiment is different from the first embodiment described above only in that the gas automatically sucked into the first nanobubble generator 2 is changed to air and used as oxygen gas. Therefore, in the third embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and parts different from those in the first embodiment will be described.

  In the third embodiment, the gas automatically sucked by the first nanobubble generator 2 is oxygen gas. Since oxygen gas has an oxidizing power rather than air, by discharging oxygen nanobubbles from the first nanobubble generator 2, it is possible to more effectively oxidize and decompose the object to be treated in the water to be treated. In addition, oxygen gas alone is more effective than air when breeding microorganisms such as microorganisms or seafood.

  In addition, oxygen is less harmful to living organisms, unlike ozone, and oxygen nanobubbles are effective when breeding microorganism cultures, seafood, and the like. In conclusion, oxygen nanobubbles are more effective for living organisms than air nanobubbles or ozone nanobubbles.

(Fourth embodiment)
Next, FIG. 4 shows a fourth embodiment of the water treatment apparatus of the present invention. This fourth embodiment is different from the first embodiment described above only in that the gas automatically sucked by the first nanobubble generator 2 and the second nanobubble generator 86 is replaced with ozone gas. Therefore, in the fourth embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and parts different from those in the first embodiment will be described.

  In the fourth embodiment, the gas automatically sucked into the first nanobubble generator 2 and the second nanobubble generator 86 is both ozone gas. Since ozone gas has an oxidizing power rather than air, by discharging ozone nanobubbles from both the first nanobubble generator 2 and the second nanobubble generator 86, the treatment object in the water to be treated is more effectively oxidized. Can be disassembled. This ozone nanobubble can maintain the oxidizing power for a long period of one month or more in water. On the other hand, in other ozone bubbles, the duration of staying in water is shorter. According to the fourth embodiment, ozone having an oxidizing power is further converted into nanobubbles having a oxidizing power by radicals, and the oxidizing power is synergistically enhanced to oxidatively decompose the object to be treated in the water to be treated. can do.

(Experimental example)
A batch-type experimental apparatus was manufactured as the nanobubble treatment apparatus 3 of the organic fluorine compound PFOS corresponding to the water treatment apparatus of the first embodiment of FIG. In this experimental apparatus, the capacity of the front decomposition unit water tank 42 in the nanobubble treatment apparatus 3 is about 1 m ³ , the capacity of the rear decomposition unit water tank 43 including the precipitation tank 51 is about 1 m ^3, and the capacity of the calcium elution part 21 is about 1 m ^3. and .5m ^3, and the capacity of the decomposition gas adsorption unit 66 about 1.5 m ^3.

The batch system of this experimental apparatus is a system in which the water treatment is not performed continuously, but is performed batchwise for each unit amount of water. Specifically, since the total capacity of the front-stage decomposition unit water tank 42 and the rear-stage decomposition unit water tank 43 is about 2 m ³ , the content of processing the PFOS-containing water to be treated is every 2 m ³ .

  The first nanobubble generator 2 and the second nanobubble generator 86 in which the motors of the gas-liquid mixing and circulation pump 5 and the gas-liquid mixing and circulation pump 55 are each configured with 3.7 KW are HYK type of Kyowa Kikai Co., Ltd. Were selected.

Moreover, in order to always supply fresh air to the calcium ion elution part 21, sirocco fan CLF5-RS type 0.75KW of Teral Co., Ltd. was selected as the fan 17. Then, industrial water was added as inflow water to the front-stage decomposition unit water tank 42 and subsequently to the rear-stage decomposition unit water tank 43 of this experimental apparatus, and then a PFOS reagent was added. As a result, after introducing 2 m ³ of industrial water for each capacity 1 m ³ of the front-stage decomposition section water tank 42 and the rear-stage decomposition section water tank 43, that is, a total capacity 2 m ³ , the introduction is stopped, and the front-stage decomposition section water tank 42 and the rear stage water tank 42 The watering pump 80 was operated and stirred and adjusted so that the PFOS concentration in the decomposition unit water tank 43 was 6000 ppb.

For the total capacity of about 2 m ³ of the rear decomposition unit water tank 43 including the front decomposition unit water tank 42 and the precipitation tank 51, 2 m ³ × 6000 ppb = 12 g of PFOS was added in total and stirred for an average PFOS concentration of 6000 ppb. It will be. As a matter of course, the industrial water charged is 2 m ³ .

  And it processed by the batch type. That is, the first nanobubble generator 2 and the second nanobubble generator 86 were operated, and the measurement data immediately after the introduction and after 6 days were compared. More specifically, the concentration of each item in the rear decomposition unit water tank 43 as the liquid phase was compared with the concentration of each item in the exhaust chimney 35 of the decomposition gas adsorption unit 66 as the gas phase.

  In addition, under the conditions in the cracked gas adsorption unit 66, measurement was performed when activated carbon was filled and when activated carbon was not filled at all. The results are shown below.

(1) Analysis results in the latter stage decomposition unit water tank 43 as a liquid phase Immediately after the PFOS was charged, the PFOS concentration was 5700 ppb, the total fluorine amount was 4600 ppb, and the free sulfate ion was 1 ppb. On the other hand, 6 days after the introduction, the PFOS concentration was 240 ppb, the total fluorine amount was 580 ppb, and the free sulfate ion was 22 ppb.

(2) Analysis result of the exhaust chimney 35 of the cracked gas adsorption unit 66 as a gas phase (when the activated gas is not filled in the cracked gas adsorption unit 66)
In this case, immediately after the introduction of PFOS, the atmospheric (gas phase) PFOS concentration was 0.02 ppb, and as a result of advanced decomposition analysis (GC-MS (gas chromatograph-mass spectrometry) measurement), the decomposition product was 0. . On the other hand, after 6 days from the introduction, the atmospheric (gas phase) PFOS concentration was 0.02 ppb, and as a result of the advanced decomposition analysis (GC-MS measurement), CF ₃ (CF ₂ ) ₃ H as a decomposition product was obtained. , CF ₃ (CF ₂ ) ₄ H and many others were confirmed.

(3) Analysis result of the exhaust chimney 35 of the cracked gas adsorption part 66 as a gas phase (when activated carbon is filled in the cracked gas adsorption part 66)
In this case, immediately after the introduction of PFOS, the atmospheric (gas phase) PFOS concentration was 0.04 ppb, and as a result of the decomposition product qualitative test, the decomposition product was 0. On the other hand, after 6 days from the introduction, the atmospheric (gas phase) PFOS concentration was 0.01 ppb, and as a result of the decomposition product qualitative test, no decomposition product could be confirmed.

  Judging from the experimental data of (1) above, the following (a) and (b) were found.

  (a) The organic fluorine compound PFOS is decomposed because it decreases as judged from the PFOS concentration in the liquid phase and the total fluorine amount.

(b) Since the free sulfate ion was detected as a decomposition product of the organic fluorine compound PFOS, the decomposition of the organic fluorine compound PFOS was proved. That is, the organic fluorine compound PFOS (C ₈ F ₁₇ SO ₃ H) was decomposed into free sulfate ions (SO ₄ ions).

  Judging from the experimental data when the activated carbon of (2) is not filled, the following (c) was found.

(c) The organic fluorine compound PFOS was decomposed, and a large number of decomposition products CF ₃ (CF ₂ ) ₃ H, CF ₃ (CF ₂ ) ₄ H, and the like were detected from the gas phase.

  Further, the following (d) and (e) were found from the experimental data when the activated carbon of (3) was filled.

  (d) The organic fluorine compound PFOS is not scattered as a PFOS mist because a high concentration PFOS is not detected from the gas phase.

(e) Since the decomposition products CF ₃ (CF ₂ ) ₃ H, CF ₃ (CF ₂ ) 4 H, and the like were not detected from the exhaust chimney 35, the decomposition products were adsorbed on the activated carbon.

It is sectional drawing which shows 1st Embodiment of the water treatment apparatus of this invention. It is sectional drawing which shows 2nd Embodiment of the water treatment apparatus of this invention. It is sectional drawing which shows 3rd Embodiment of the water treatment apparatus of this invention. It is sectional drawing which shows 4th Embodiment of the water treatment apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inflow piping 2 1st nano bubble generator 3 Nano bubble processing apparatus 4 Suction piping 5 Gas-liquid mixing circulation pump 6 1st gas shearing part 7 Water piping 8 2nd gas shearing part 9 Water piping 10 Air piping 11 Electric needle valve 12 3rd Gas shear part 13 Nano bubble flow 14 Water pipe 15 Water flow 16 Suction port 17 Fan 18 Discharge duct 19 Duct flange 20 Decomposition unit 21 Calcium ion elution unit 22 Lower outlet 23 Middle outlet 24 Upper outlet 25 Water surface 26 Lower fixed hole Table 27 Middle fixed hole perforated base 28 Upper fixed hole perforated base 29 Lower charcoal storage container 30 Middle charcoal storage container 31 Upper charcoal storage container 32 Lower calcium carbonate mineral 33 Intermediate calcium carbonate mineral 34 Upper calcium carbonate mineral 35 Exhaust chimney 36 Outflow water piping 37 Process gas 38 Primary decomposition product gas 39 Fresh Airflow 40 Inclined wall 41 Adsorption box 42 Front decomposition unit water tank 43 Rear decomposition unit water tank 44 Flange 45 Sprinkling nozzle 46 Sprinkling water pipe 47 Duct 48 Inclined plate 49 Decomposed gas 50 Partition plate 51 Precipitation tank 52 Drain valve 53 Calcium sulfate flock 54 Suction pipe 55 Gas-liquid mixing circulation pump 56 First gas shearing part 57 Water pipe 58 Second gas shearing part 59 Water pipe 60 Air pipe 61 Electric needle valve 62 Third gas shearing part 63 Nano bubble flow 64 Sedimentation tank inclined wall 65 Water flow 66 Decomposition gas Suction part 67 Lower outlet 68 Middle outlet 69 Upper outlet 70 Lower fixed hole base 71 Intermediate fixed hole base 72 Upper fixed hole base 73 Lower activated carbon storage container 74 Intermediate activated carbon storage container 75 Upper activated carbon storage container 76 Lower activated carbon 77 Middle activated carbon 78 Upper activated carbon 79 Inclined wall 80 Sprinkling Pump 81 Suction piping 82 Water droplets 83 containing nano bubbles 83 Water flow 84 Process gas 85 Secondary decomposition product gas 86 Second nano bubble generator

Claims (27)

A water tank into which water containing a hardly decomposable compound is introduced;
A gas-liquid mixed gas shearing nanobubble generator for discharging nanobubbles into the hardly decomposable compound-containing water in the water tank;
A water treatment apparatus comprising: a gas removal unit that removes a decomposition product of the hardly decomposable compound that has been decomposed and gasified by oxidizing power of radicals of the nanobubbles in the water tank. The water treatment apparatus according to claim 1,
The water treatment apparatus, wherein the hardly decomposable compound is an organic compound. The water treatment device according to claim 2,
The hardly decomposable compound is an organic fluorine compound,
A pre-stage water tank into which the organic fluorine compound-containing water is introduced;
A first nanobubble generator of a gas-liquid mixed gas shearing system that discharges nanobubbles to the organic fluorine compound-containing water in the front stage water tank;
A rear water tank into which treated water from the front water tank is introduced;
A second nanobubble generator of a gas-liquid mixed gas shearing system that discharges nanobubbles to the organic fluorine compound-containing water in the rear water tank;
A water treatment apparatus comprising: a gas removing unit that adsorbs and removes the gasified decomposition product of the organic fluorine compound decomposed by the oxidizing power of radicals of the nanobubbles in the rear water tank. The water treatment apparatus according to claim 3,
The organic fluorine compound-containing water is
A water treatment apparatus comprising at least one of PFOS and PFOA. In the water treatment apparatus according to any one of claims 1 to 4,
The nano-bubble generator has a three-stage gas-liquid mixed gas shearing section. In the water treatment equipment according to any one of claims 3 to 5,
A calcium ion elution part that is arranged on the front stage water tank and into which nanobubbles from the front stage water tank are introduced to drop calcium ions into the front stage water tank,
A settling tank in which treated water is introduced from the front water tank and the treated water is introduced into the rear water tank;
A water treatment apparatus, comprising: a gas adsorbing portion that is disposed on the rear water tank and that adsorbs a gas generated by decomposing an organic fluorine compound with the nanobubbles using an adsorbent. The water treatment device according to claim 6,
A water treatment apparatus comprising an air supply unit for supplying air between the front-stage water tank and the calcium ion elution unit. The water treatment apparatus according to claim 6 or 7,
A water treatment apparatus, wherein the adsorbent of the gas adsorption unit is activated carbon. In the water treatment equipment according to any one of claims 1 to 8,
The nano bubble generator is
A gas-liquid mixing circulation pump having a first gas shearing part capable of introducing gas by an electric needle valve;
A second gas shearing part into which microbubbles are introduced from the first gas shearing part;
A water treatment apparatus comprising: a third gas shearing part into which nanobubbles are introduced from the second gas shearing part. The water treatment device according to claim 9,
A water treatment apparatus, wherein air is introduced from the electric needle valve to the first gas shearing portion at a rate of 1.2 liters / minute or less. The water treatment device according to claim 9,
The said 1st gas shearing part is an elliptical shape or a perfect circle shape, and the 2 or more groove | channel is formed in the inside, The water treatment apparatus characterized by the above-mentioned. The water treatment device according to claim 11,
A water treatment apparatus having a nanobubble generator, wherein the groove has a depth of 0.3 mm to 0.6 mm and a groove width of 0.8 mm or less. In the water treatment equipment according to any one of claims 9 to 12,
In the gas-liquid mixing circulation pump, the inner diameter of the discharge pipe is smaller than the inner diameter of the suction pipe. In the water treatment equipment according to any one of claims 9 to 13,
The water treatment apparatus, wherein the gas / liquid mixing / circulation pump starts gas intake after the pump output of the gas / liquid mixing / circulation pump reaches a maximum value. In the water treatment equipment according to any one of claims 9 to 13,
The gas-liquid mixing / circulation pump starts to take in gas after 60 seconds or more have elapsed from the start of operation. In the water treatment equipment according to any one of claims 9 to 15,
The gas inflow pipe for allowing the gas to flow from the electric needle valve to the first gas shearing portion is arranged so that an incident angle with respect to the side surface of the microbubble generating portion of the first gas shearing portion is 18 °. Water treatment equipment. In the water treatment equipment according to any one of claims 9 to 15,
A water treatment apparatus characterized in that the thickness of the material constituting the first gas shearing section is 6 mm to 12 mm. In the water treatment equipment according to any one of claims 1 to 17,
A water treatment apparatus characterized in that the gas supplied to the nanobubble generator is ozone. In the water treatment equipment according to any one of claims 1 to 17,
A water treatment apparatus characterized in that the gas supplied to the nanobubble generator is oxygen gas. The nanobubbles are discharged into the water containing the hardly decomposable compound and mixed.
A water treatment method characterized by decomposing a strong bond of the hardly decomposable compound by utilizing the oxidizing power of radicals possessed by the nanobubble, and gasifying and removing a decomposition product by the decomposition. The water treatment method according to claim 20,
The water treatment method, wherein the hardly decomposable compound is an organic compound. The water treatment method according to claim 21, wherein
The hardly decomposable compound is an organic fluorine compound,
Nanobubbles are discharged and mixed into the organic fluorine compound-containing water, and the strong bond between carbon and fluorine of the organic fluorine compound is decomposed using the oxidizing power of the radicals of the nanobubbles, A first process for gasification and removal;
The nanobubbles are discharged and mixed in the treated water after the first treatment, and the strong bond between carbon and fluorine of the organic fluorine compound is decomposed using the oxidizing power of the radicals of the nanobubbles. The water treatment method characterized by performing the 2nd process which gasifies and removes a decomposition product. The water treatment method according to claim 22,
In the first treatment, a sulfate treatment ion of the decomposition product is removed by reacting with calcium ions. The water treatment method according to claim 23,
A water treatment method, wherein a water droplet containing nanobubbles is dropped on a calcium carbonate mineral to elute the calcium ions. The water treatment method according to claim 24,
A water treatment method, wherein water droplets containing nanobubbles are dropped on the calcium carbonate mineral, and the gasified low molecular organic fluorine compound is further decomposed into low molecules on the surface of the calcium carbonate mineral. The water treatment method according to claim 25,
A water treatment method characterized by reacting calcium ions eluted from the calcium carbonate mineral with fluorine ions generated by decomposition of the low-molecular-weight organic fluorine compound to form a precipitate of calcium fluoride. The water treatment method according to claim 25,
Calcium fluoride flocs are produced by reacting calcium ions eluted from the calcium carbonate mineral with fluorine ions generated by the decomposition of the low molecular weight organic fluorine compound in the presence of nanobubbles to form calcium fluoride flocs. A water treatment method characterized by precipitating water in a precipitation tank.

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