JP2010046648A - Water treatment apparatus and water treatment method - Google Patents

Abstract

A water treatment technique capable of efficiently removing a hardly decomposable compound in an aqueous solution.
A nanobubble generator 16 for generating nanobubbles 30 in water to be treated, a decomposition unit 19 for storing water to be treated containing nanobubbles 30, and a decomposition unit for storing water to be treated containing nanobubbles. , And a space into which gas generated from the decomposition unit 19 is introduced, and a decomposition adsorption tank 20 constituted by the gas adsorption unit 18 in which the fine activated carbon 33 is placed, and a treatment object stored in the decomposition unit 19 Provided is a water treatment device including a diffuser pipe for aeration of water.
[Selection] Figure 1

Description

  The present invention relates to a water treatment apparatus and a water treatment method, and more particularly to a water treatment apparatus and a water treatment method using nanobubbles.

  Dioxins, organic fluorine compounds (eg, perfluorooctane sulfonic acid (PFOS) or perfluorooctanoic acid (PFOA)) are chemically stable substances, and have heat resistance and chemical resistance (eg, acid resistance). Is excellent. Therefore, these hardly decomposable compounds are widely used as surfactants or industrial materials such as antireflection films in semiconductor production.

  However, the more widely used these hardly decomposable compounds are, the more likely they are released to nature.

  As described above, since a hardly decomposable compound is a chemically stable substance, once it is released into nature, it can cause serious environmental pollution. For example, the above-mentioned hardly decomposable compounds have been detected from the polar bears, seals and whales, and environmental pollution due to the hardly decomposable compounds is becoming increasingly serious internationally.

  Therefore, in order to prevent environmental pollution, development of water treatment technology for appropriately treating waste water from factories using these hardly decomposable compounds as industrial materials is being promoted. In water treatment, a water treatment technique for removing these hardly decomposable compounds remaining in river water and the like is also required at the same time.

  For example, conventionally, as a water treatment technique for wastewater containing refractory compounds such as PFOS and PFOA, a combustion method in which a refractory compound is burned in an aqueous solution using fuel, or a high pressure is applied to an aqueous solution. A supercritical method is used in which a compound in an aqueous solution is decomposed by application.

  However, for example, the concentration of the organic fluorine compound in the organic fluorine compound-containing wastewater discharged from a semiconductor factory or the like is on the order of ppb, the concentration is low, and the amount of wastewater is several tens to several hundred tons per day. Many. In this case, in the present situation, the conventional method cannot completely treat the waste water.

  In addition, in the water treatment, the concentration of organic fluorine compounds in river water and lake water is much lower than in the case of drainage, and the amount of water is large, so that treatment is very difficult.

  By the way, in recent years, it is becoming clear that bubbles having a small diameter have various functions and effects. Currently, research on techniques for producing such bubbles and their effects is in progress. Attempts have also been made to decompose various organic substances using bubbles.

  The bubbles can be classified into microbubbles, micronanobubbles and nanobubbles according to their diameters. Specifically, the microbubble is a bubble having a diameter of 10 μm to several tens of μm at the time of its generation, the micro-nano bubble is a bubble having a diameter of several hundred nm to 10 μm at the time of its generation, and the nanobubble is Bubbles having a diameter of several hundred nm or less at the time of generation. Note that a part of the microbubble may be changed to a micro / nanobubble by the contraction movement after the generation. Nanobubbles have the property that they can exist in a liquid for a long period of time.

  For example, conventionally, various utilization methods of nanobubbles and various apparatuses utilizing nanobubbles are known (see, for example, Patent Document 1). More specifically, in Patent Document 1, nanobubbles exhibit surface-active action and bactericidal action by reducing buoyancy, increasing surface area, increasing surface activity, generating a local high-pressure field, or realizing electrostatic polarization. It is described. Furthermore, Patent Document 1 describes a technique for cleaning various objects and a technique for purifying polluted water using the surface active action and bactericidal action of nanobubbles. Furthermore, Patent Literature 1 describes a method for recovering fatigue of a living body using nanobubbles. In Patent Literature 1, nanobubbles are produced by electrolyzing water and applying ultrasonic vibration to the water.

  Conventionally, a method for producing nanobubbles using a liquid as a raw material is known (see, for example, Patent Document 2). In the liquid, the production method includes 1) a step of decomposing and gasifying a part of the liquid, 2) a step of applying ultrasonic waves to the liquid, or 3) a step of decomposing and gasifying a part of the liquid; A step of applying ultrasonic waves to the liquid. It is described that an electrolysis method or a photolysis method can be used as a step of decomposing and gasifying a part of the liquid.

Conventionally, a waste liquid treatment apparatus using microbubbles (ozone microbubbles) made of ozone gas has been used (see, for example, Patent Document 3). In the waste liquid treatment apparatus, microbubbles made of ozone gas are produced by mixing the ozone gas produced by the ozone generator and the waste liquid using a pressure pump. And when the said microbubble reacts with the organic substance in a waste liquid, the organic substance in a waste liquid is oxidized and decomposed | disassembled.
JP 2004-121962 A (published April 22, 2004) JP 2003-334548 A (published on November 25, 2003) JP 2004-321959 A (published November 18, 2004)

  However, the conventional water treatment technology using bubbles has a problem in that the hardly decomposable compound in the aqueous solution cannot be efficiently removed.

  This invention is made | formed in view of the said conventional problem, Comprising: The objective is to provide the water treatment technique which can remove the hardly decomposable compound in aqueous solution efficiently.

As a result of intensive studies to solve the above problems, the present inventors have found the following 1) to 3) and completed the present invention.
1) When decomposing a hardly decomposable compound (for example, an organic fluorine compound) by utilizing the oxidizing power of nanobubbles, when activated carbon is added, decomposition proceeds efficiently due to the adsorption action of activated carbon;
2) When a hardly decomposable compound is decomposed using the oxidizing power of nanobubbles and the adsorption action of activated carbon, decomposed products having a reduced carbon number (for example, C3, C4, C5, C6, C7, etc.) are gasified, The gas is released into the gas phase;
3) The decomposed product of the gasified hardly decomposable compound is to be efficiently adsorbed and decomposed by the finely pulverized activated carbon generated by partially pulverizing the activated carbon.

  That is, the water treatment apparatus according to the present invention introduces nanobubble generating means for generating nanobubbles in the water to be treated, a decomposition part for storing the water to be treated containing the nanobubbles, and a gas generated from the decomposition part. A decomposition adsorption tank constituted by a gas adsorption unit in which fine activated carbon is placed, and an aeration means for aerating the water to be treated stored in the decomposition unit It is said.

  According to said structure, the to-be-decomposed substance in to-be-processed water can be decompose | disassembled efficiently by the oxidizing power of nanobubble and the aeration by an aeration means. In addition, since the decomposed part is aerated, the gasified decomposed product can be efficiently sent to the water surface, and the gas-phase air can be replaced. Can be sent to. Moreover, since fine activated carbon has a larger surface area than ordinary activated carbon and higher adsorption efficiency, the decomposition product gasified in the gas adsorption part is efficiently adsorbed by the fine activated carbon. Therefore, with the above configuration, the hardly decomposable compound in the aqueous solution can be efficiently removed.

  Moreover, in the water treatment apparatus according to the present invention, the water to be treated may contain an organic fluorine compound.

  According to said structure, the strong coupling | bonding between carbon and fluorine of an organic fluorine compound can be decomposed | disassembled by the oxidizing power of nanobubbles, and the adsorption effect of activated carbon.

  In the water treatment apparatus according to the present invention, activated carbon is put in the decomposition section, and the fine activated carbon is fine activated carbon generated by aeration and crushing of the activated carbon by the aeration means. preferable.

  According to said structure, a to-be-decomposed substance can be adsorption-treated in a decomposition | disassembly part by adding activated carbon to a decomposition | disassembly part. Moreover, the fine activated carbon can be reused by transferring the fine activated carbon that has been aerated and crushed from the decomposition section to the gas adsorption section. Moreover, since activated carbon has a certain size and weight, it can be charged more easily than fine activated carbon and is easy to handle.

  Moreover, in the water treatment apparatus according to the present invention, a rapid filter that filters the water to be treated in the decomposition unit, and a fine activated carbon transfer unit that transfers the fine activated carbon separated in the rapid filter to the gas adsorption unit. Is preferably further provided.

  According to said structure, a fine activated carbon and a suspended | floating matter can be removed from to-be-processed water with a rapid filter, and also a fine activated carbon can be reused.

  Moreover, the water treatment apparatus according to the present invention further includes backwashing means for backwashing the rapid filter, and the fine activated carbon transfer means is formed by backwashing water that is flown out by the backwashing means. It is preferable to transfer the fine activated carbon separated in the rapid filter to the gas adsorption unit.

  According to said structure, the backwash pump of the said backwashing means is operated with the rapid filter pump of a rapid filter, and backwash water is made to flow out to a gas adsorption | suction part. Thereby, the fine activated carbon deposited on the rapid filter can be introduced into the gas adsorbing portion to reuse the fine activated carbon, and the rapid filter can be washed.

  In the water treatment apparatus according to the present invention, it is preferable that the fine activated carbon transfer means further includes an automatic valve for removing the broken fine activated carbon contained in the backwash water.

  According to said structure, the adsorption | suction process of a decomposition product can be performed efficiently by removing the said fine activated carbon which broke through and the adsorption | suction capability was lose | eliminated.

  In the water treatment apparatus according to the present invention, it is preferable that the rapid filter has a space for depositing the fine activated carbon.

  According to said structure, a fine activated carbon can be deposited in a filter and a fine activated carbon can be reused successfully.

  Moreover, in the water treatment apparatus according to the present invention, the decomposition unit includes a side surface that is inclined so that a cross-sectional area in the horizontal direction increases toward the top, a discharge port provided in the side surface, and an activated carbon larger than the fine activated carbon. Is preferably provided with an overflow plate provided so as not to flow out of the outlet.

  According to said structure, since the decomposition | disassembly part is provided with the inclined side surface, activated carbon can be efficiently flowed. Moreover, since the discharge port and the overflow plate are installed on the inclined side surface, normal activated carbon does not flow out, only fine activated carbon can flow out, and the fine activated carbon can be successfully reused.

  Moreover, in the water treatment apparatus according to the present invention, it is preferable that the gas adsorption unit includes a filler for attaching the fine activated carbon.

  According to said structure, since a large amount of fine activated carbon can be provided in a gas adsorption | suction part by providing a filler, decomposition product gas can be adsorbed efficiently.

  In the water treatment apparatus according to the present invention, the filler is preferably made of plastic.

  According to said structure, since a filler is a molded article which consists of plastics, it can obtain or manufacture easily.

  In the water treatment apparatus according to the present invention, the filler may be made of ring-type polyvinylidene chloride.

  According to said structure, since ring-type polyvinylidene chloride has many surface areas, a lot of fine activated carbon can be made to adhere and decomposition product gas can be made to adhere efficiently.

  In the water treatment apparatus according to the present invention, the filler may be a mesh sheet.

  According to said structure, since a mesh sheet | seat has many surface areas, a lot of fine activated carbon can be made to adhere and decomposition product gas can be made to adhere efficiently.

  The water treatment apparatus according to the present invention further includes a nanobubble generating water tank for storing the treated water, and a treated water transfer means for transferring the treated water from the nanobubble generating water tank to the decomposition adsorption tank. Preferably, the nanobubble generating means generates the nanobubbles in the water to be treated stored in the nanobubble generating water tank.

  According to the above configuration, by introducing nanobubbles into the water to be treated in a nanobubble generating water tank different from the decomposition adsorption tank, the activated carbon enters the nanobubble generating means even in a configuration in which activated carbon is included in the decomposition part. Therefore, the nanobubble generating means can generate nanobubbles in an ideal state.

  Moreover, in the water treatment apparatus according to the present invention, the nanobubble generating means further shears the microbubble-containing water with a first gas shearing section that mixes and shears a liquid and a gas to produce microbubble-containing water. It is preferable to include a second gas shearing unit that produces nanobubble-containing water and a third gas shearing unit that further shears the nanobubble-containing water to produce nanobubble-containing water containing a large amount of nanobubbles.

  According to said structure, a lot of nanobubbles can be produced | generated efficiently.

  Moreover, in the water treatment apparatus according to the present invention, the cross section inside the first gas shearing portion is an ellipse or a true circle, and two or more grooves are formed on the inner surface of the first gas shearing portion. It is preferable to be provided.

  According to said structure, the rotation turbulent flow of the fluid in a microbubble generation part can be controlled.

  In the water treatment apparatus according to the present invention, the depth of the groove is preferably 0.3 mm to 0.6 mm, and the width of the groove is preferably 0.8 mm or less.

  According to said structure, the rotation turbulent flow of the fluid in a microbubble generation part can be controlled more effectively.

  Moreover, in the water treatment apparatus according to the present invention, in the first gas shearing section, the liquid is supplied through the first pipe, and the microbubble-containing water is discharged through the second pipe, so that the first The area of the cross section of the lumen of the pipe is preferably larger than the area of the cross section of the lumen of the second pipe.

  According to said structure, shearing of air can be performed rationally and stably, and microbubbles can be manufactured in large quantities.

  Moreover, in the water treatment apparatus according to the present invention, the nanobubble generating means supplies a liquid to the first gas shearing part, mixes and circulates the liquid and the gas, and the first gas shearing part. It is preferable to further include a third pipe for supplying gas to the gas and gas amount adjusting means for adjusting the amount of gas supplied to the first gas shearing portion.

  According to said structure, a lot of nanobubbles can be produced | generated.

  In the water treatment apparatus according to the present invention, it is preferable that the gas amount adjusting means supplies the gas at a rate of 1.2 liter / min or less to the first gas shearing portion.

  According to said structure, a lot of nanobubbles can be produced | generated.

  In the water treatment apparatus according to the present invention, it is preferable that the gas is taken into the first gas shearing section after the time when the output of the gas-liquid mixing circulation pump reaches the maximum value.

  According to the above configuration, only the liquid is supplied at first, and the gas is introduced after the pump output reaches the maximum value, so that cavitation does not occur and the pump is not damaged.

  In the water treatment apparatus according to the present invention, it is preferable that the gas is taken into the first gas shearing section after 60 seconds from the start of the operation of the gas-liquid mixing circulation pump.

  According to the above configuration, the pump output reaches the maximum value after 60 seconds from the start of the operation of the gas-liquid mixing circulation pump. Therefore, with the above configuration, cavitation does not occur and the pump is not damaged.

  Moreover, in the water treatment apparatus according to the present invention, the third pipe is connected to the first gas shearing portion so as to form an angle of 18 degrees with respect to the inner surface of the first gas shearing portion. Is preferred.

  According to the above configuration, a large amount of microbubbles can be generated.

  Moreover, in the water treatment apparatus according to the present invention, the thickness of the partition wall of the first gas shearing part is preferably 6 mm to 12 mm.

  According to said structure, a microbubble can be generated stably.

  Moreover, it is preferable that the water treatment apparatus according to the present invention further includes an activated carbon adsorption tower activated carbon adsorption tower that performs adsorption treatment of the water to be treated filtered in the rapid filter.

  According to said structure, a trace amount compound can further be adsorbed.

  Moreover, it is preferable that the water treatment apparatus according to the present invention further includes an ion exchange resin tower that performs adsorption treatment of the water to be treated filtered in the rapid filter.

  According to said structure, a trace amount compound can further be adsorbed.

  In the water treatment apparatus according to the present invention, the fine activated carbon preferably has an average particle size of 0.2 mm or less.

  According to said structure, fine activated carbon can adsorb | suck decomposition-product gas more successfully.

  Moreover, the water treatment method according to the present invention is a water treatment method for treating water to be treated containing an organic fluorine compound, and the nanowater and activated carbon are added to the water to be treated, and the oxidizing power of the nanobubbles, The organic fluorine compound is decomposed and adsorbed by the adsorption action of the activated carbon.

  According to said structure, the strong coupling | bonding of carbon of an organic fluorine compound and fluorine can be decomposed | disassembled by the oxidizing power by the radical which nanobubble has, and the adsorption effect of activated carbon.

  In the water treatment method according to the present invention, the organic fluorine compound is selected from perfluorooctanesulfonic acid, perfluorooctanoic acid, perfluoroalkylsulfonic acid, perfluorooctanesulfonic acid fluoride, and perfluorooctanesulfonic acid fluoride derivatives. One or more organic fluorine compounds selected from the group may be used.

  According to said structure, even if it is a hardly decomposable substance as mentioned above, it can decompose | disassemble successfully.

  According to the water treatment apparatus of the present invention, the hardly decomposable compound in the aqueous solution can be efficiently removed.

[First Embodiment]
An embodiment of a water treatment apparatus according to the present invention will be described below with reference to FIG. FIG. 1 is a diagram showing an embodiment of a water treatment apparatus according to the present invention.

  As shown in FIG. 1, the water treatment apparatus according to this embodiment includes a raw water tank 2, a nanobubble generation water tank 15, a decomposition adsorption tank 20, a first pit water tank 40, a rapid filter 44, and a second pit water tank 56. It is comprised by.

  The raw water tank 2 is a water tank for storing the treated water, and a raw water pump 3 for pumping up the treated water is installed. To-be-treated water is introduced into the raw water tank 2 through the pipe 1.

  The water to be treated is an aqueous solution containing a substance to be decomposed such as an organic fluorine compound, for example, water containing organic fluorine compound discharged from each factory, or general river water or general lake water containing a small amount of organic fluorine compound. Etc. Examples of the organic fluorine compound include perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluoroalkylsulfonic acid, perfluorooctanesulfonic acid fluoride, and perfluorooctanesulfonic acid fluoride derivatives. .

  The nano bubble generating water tank 15 is a water tank for generating nano bubbles in the water to be treated, and includes a nano bubble generator (nano bubble generating means) 16 for generating the nano bubble flow 13 in the water to be treated. The configurations of the nanobubble 30 and the nanobubble generator 16 will be described later. To-be-processed water is introduced into the nanobubble generating water tank 15 from the raw water tank 2 through the pipe 14 by the raw water pump 3. The treated water containing the nanobubbles 30 flows out of the nanobubble generation water tank 15 due to overflow, and flows to the decomposition unit 19 of the decomposition adsorption tank 20 through the overflow water pipe (treated water transfer means) 17.

  Since the nanobubble generator 16 is provided in the nanobubble generator 15, activated carbon 31 or the like added to the decomposition unit 19 described later does not enter the nanobubble generator 16, so that the nanobubbles 30 are generated in the water to be treated in an ideal state. be able to. In the nanobubble generating water tank 15, the time for which the water to be treated stays is as short as several minutes to several tens of minutes, so that it hardly contributes to the decomposition of the substances to be decomposed contained in the water to be treated.

  The decomposition adsorption tank 20 is a water tank for storing the water to be treated, and is a water tank for further decomposing and adsorbing the water to be treated. As shown in FIG. 1, the decomposition adsorption tank 20 includes a decomposition unit 19 and a gas adsorption unit 18 provided on the upper part of the decomposition unit 19. The decomposition unit 19 is filled with the water to be treated, and the gas adsorption unit 18 is a space into which the gas generated in the decomposition unit 19 is introduced, and is formed, for example, above the water to be treated.

  The decomposition unit 19 will be described in detail below.

  As shown in FIG. 1, the decomposition unit 19 includes a rectifying plate 28, an overflow plate 32, a discharge port 64, an air diffuser (aeration means) 36, and an inclined side wall 34. In addition, the water to be treated containing nanobubbles is introduced from the nanobubble generating water tank 15 into the decomposition unit 19 through the overflow water pipe 17. The treated water in the decomposition unit 19 includes nanobubbles 30, activated carbon 31, and fine activated carbon 33.

  The rectifying plate 28 is provided to adjust the flow so that the water to be treated is efficiently stirred in the decomposition unit 19.

  The overflow plate 32 is provided on the inclined side wall 34 and prevents the activated carbon 31 larger than the fine activated carbon 33 from flowing out from the discharge port 64. The fine activated carbon 33 flows out from the discharge port 64 together with the water to be treated by the water flow that overflows the overflow plate 32.

  The discharge port 64 is a hole having a size through which the water to be treated and the fine activated carbon 33 pass, and is connected to the pipe 39. The shape of the hole to be formed is not particularly limited. The discharge port 64 is preferably provided on the side surface of the disassembling part 19, and more preferably provided on the inclined surface. Moreover, it is preferable that the discharge port 64 is provided so that activated carbon 31 or the like larger than the fine activated carbon 33 does not flow out. The water to be treated in the decomposition unit 19 flows out from the discharge port 64 due to overflow together with the fine activated carbon 33, and flows into the first pit water tank 40 through the pipe 39.

  The air diffuser 36 is installed at the lower part of the decomposition unit 19 and is connected to the blower 38 to aerate the air discharged from the blower 38 into the decomposition unit 19. Due to aeration from the air diffuser 36, the inside of the decomposition unit 19 is strongly stirred. The place where the air diffusing pipe 36 is installed is not particularly limited, but is preferably the bottom of the decomposition unit 19. By installing the air diffuser 36 at the bottom, the activated carbon 31 is efficiently stirred.

  The side wall 34 is one of the side walls of the disassembling part 19, and is inclined so that the horizontal sectional area of the disassembling part 19 increases toward the top. The angle formed between the bottom surface 35 and the side wall 34 of the disassembling part 19 is not particularly limited, but is preferably 45 degrees or more and 60 degrees or less, for example. Since at least one of the side walls of the decomposition part 19 is inclined, the inside of the decomposition part 19 is efficiently stirred by aeration. Moreover, since the bottom part is narrow, the activated carbon 31 which settles is collected in the narrow range of a bottom part, and is efficiently flowed by the aeration from the diffuser pipe 36 installed in the lower part.

  The blower 38 is installed outside the decomposition adsorption tank 20 and discharges air to the air diffusion pipe 36 through the air pipe 37. As the electric motor for operating the blower 38, it is preferable to select an electric motor of a type that can control the rotation speed in order to perform inverter operation. By controlling the rotational speed of the electric motor, the total amount of fine activated carbon 33 in the water treatment apparatus according to the present invention can be adjusted.

Air amount for aerating the decomposition section 19 is not particularly limited, but is preferably that amount that causes a aeration intensity activated carbon 31 is agitated, for example, water tank capacity per 50 (m 3 ^/ time / m ³ ) Or more. If the amount of air causes strong aeration, the activated carbon 31 is caused to flow, and a decomposition gas in the decomposition unit 19 such as PFC gas: perfluorocarbon gas, which is a decomposition product of an organic fluorine compound, is moved to the water surface. Further, it can be sent to the gas adsorption unit 18 as a decomposed gas 63.

  The nanobubbles 30 are nanobubbles generated in the water to be treated in the nanobubble generating water tank 15 as described above, and flow into the decomposition unit 19 together with the water to be treated.

  Radicals are generated by the nanobubbles 30, and the hardly decomposable compounds in the water to be treated are oxidatively decomposed by the radicals. For example, although PFOS and PFOA are known to be stable substances, these substances can be oxidatively decomposed by the water treatment apparatus of the present embodiment. The inventors of the present application have found that the decomposition product generated by the oxidative decomposition reaction is gasified from the surface of the water to be treated in the decomposition adsorption tank 20 and released into the atmosphere. That is, as shown in FIG. 1, the decomposition product is released from the water surface as decomposition product gas 63.

The decomposition product gas 63 is gasification of the decomposition product of the decomposition target substance contained in the water to be treated. For example, when the substance to be decomposed is an organic fluorine compound such as PFOS and PFOA, examples of the decomposition gas 63 include CF ₃ (CF ₂ ) _n H (n = 3, 4, 5, 6), CF ₃ (CF ₂ ) _m COOCH ₃ (m = 5, 6).

The activated carbon 31 has a function of adsorbing a substance to be decomposed and is introduced for an adsorption action. A certain amount of the activated carbon 31 is introduced into the decomposition adsorption tank 20 from an activated carbon charging port 62 to be described later, falls into the treated water in the decomposition unit 19, and contributes to the adsorption treatment of the decomposed substances contained in the treated water. To do. Since the specific gravity of the activated carbon 31 is greater than 1, the activated carbon 31 tends to gather at the bottom of the decomposition unit 19, and as a result, the activated carbon 31 flows efficiently in the decomposition unit 19 by aeration from the air diffuser 36 at the lower portion. Can touch. Examples of the activated carbon 31 include granular activated carbon. For example, it is preferable to use “Kuraray Coal (registered trademark)” (manufactured by Kuraray Chemical Co., Ltd.) which is granular activated carbon (for liquid phase). The activated carbon 31 according to the present invention preferably has an average particle size of about 1.0 mm. The amount of activated carbon is added to the water treatment apparatus according to the present invention is preferably a capacity per 0.2 to 0.4 of the decomposition section ^{19 (cm 3 / cm 3)} .

  By adding the activated carbon 31, the substance to be decomposed can be efficiently decomposed by the oxidizing power of the nanobubbles 30 and the catalytic action of the activated carbon 31.

  The fine activated carbon 33 has an adsorption action like the activated carbon 31 and is finer than the activated carbon 31, in other words, activated carbon having a specific surface area (surface area per unit mass) larger than that of the activated carbon 31. Since the adsorption efficiency is higher because the specific surface area is larger than that of the activated carbon 31, the substance to be decomposed can be efficiently decomposed by introducing the fine activated carbon 33. In the present embodiment, as the fine activated carbon 33, the fine activated carbon 33 generated by the activated carbon 31 being crushed by strong aeration in the decomposition unit 19 is used, and the fine activated carbon 33 is further transferred from the decomposition unit 19 to the gas adsorption unit 18. It is transported. In the present embodiment, the fine activated carbon 33 is transferred by alternately performing the filtration step and the backwashing step in the rapid filter 44 described later, but the transfer method is not particularly limited.

  Since the adsorption efficiency of the fine activated carbon 33 increases as the surface area increases, the fine activated carbon 33 according to the present invention is preferably as fine as possible, and the average particle size is more preferably 0.2 mm or less.

  In addition, as the fine activated carbon 33 which concerns on this invention, activated carbon separately crushed, a commercially available fine activated carbon, etc. can also be used. In that case, the fine activated carbon 33 may be transferred from the activated carbon charging port 62 described later into the decomposition unit 19 and then transferred from the decomposition unit 19 to the gas adsorption unit 18, or from the upper part of the gas adsorption unit 18. May be. However, for the reason that the activated carbon 31 is larger than the fine activated carbon 33 and is easy to handle, it is preferable in the present invention to use the fine activated carbon 33 generated by crushing the activated carbon 31 by aeration in the decomposition unit 19. That is, if further refinement of the fine activated carbon 33 is promoted in order to increase the surface area, the fine activated carbon 33 becomes a powder, which causes a problem in handling such as rolling up at the time of charging. Therefore, as in the present embodiment, a method in which a slightly larger size of activated carbon 31 is introduced into the decomposition unit 19 and crushed by strong aeration to form fine activated carbon 33 and then transferred to the gas adsorption unit 18 is more rational. is there.

  Next, the gas adsorption unit 18 will be described in detail.

  The gas adsorbing unit 18 is a space for adsorbing the decomposition product gas 63 described above, and is provided at the upper portion of the decomposition unit 19 as shown in FIG. 1, and includes a perforated base 21, a plastic filler (filler). ) 22, watering pipe 24, fastener 23, watering nozzle 27, exhaust chimney 25, and activated carbon charging port 62. Further, fine activated carbon 33 is attached to the plastic filler 22.

  The perforated base 21 is formed and fixed so as to divide the decomposition adsorption tank 20 horizontally, and has a structure that can support the plastic filler 22. The perforated base 21 is formed with a hole through which gas, liquid, fine activated carbon and the like can pass.

  The plastic filler 22 is a filler for attaching the fine activated carbon 33 and is provided on a perforated base. Examples of the plastic filler 22 include a S-II type made of polyethylene manufactured by Tsukishima Environmental Engineering Co., Ltd. In this embodiment, a plastic filler is used as the filler. However, in the present invention, the material of the filler may not be plastic, and may be a material that easily attaches the fine activated carbon 33. preferable. By providing the filler, a large amount of fine activated carbon 33 can be provided in the gas adsorbing portion 18, so that the decomposition product gas 63 can be adsorbed efficiently.

  The sprinkling pipe 24 is connected to a pipe 46 connected to a rapid filter 44 described later, and is a pipe through which backwash water obtained by backwashing the rapid filter 44 is passed.

  The fastener 23 is a fastener formed so as to close the end of the sprinkling pipe 24.

  The watering nozzle 27 is installed in the watering pipe 24 at regular intervals, and sprays the backwash water flowing through the watering pipe 24 into the gas adsorbing unit 18.

  The exhaust chimney 25 is provided in the upper part of the gas adsorption unit 18 and is a chimney for discharging the air in the gas adsorption unit 18.

  The activated carbon charging port 62 is a charging port for charging the activated carbon 31 into the decomposition adsorption tank 20, and is provided below the perforated base 21. Activated carbon 31 charged from the activated carbon charging port 62 falls into the water to be treated in the decomposition unit 19.

  The decomposition product gas 63 flows from the decomposition unit 19 into the gas adsorption unit 18, and the decomposition product contained in the decomposition product gas 63 is adsorbed by the fine activated carbon 33 attached to the plastic filler 22, so that a new decomposition product is obtained. The gas adsorbing portion 18 is raised by the inflow of the gas 63 and the diffusion effect. Thereafter, the exhaust gas 26 is exhausted from the exhaust chimney 25.

  The exhaust gas 26 is a gas obtained by adsorbing the decomposition product gas 63 in the gas adsorption unit 18, and is exhausted from the exhaust chimney 25 installed in the upper part.

  The first pit water tank 40 is a water tank for storing the water to be treated and fine activated carbon 33 that have flowed out of the decomposition unit 19 of the decomposition adsorption tank 20. The first pit water tank 40 is provided with a rapid filter pump 41 for pumping up water to be treated. The treated water in the first pit water tank 40 is sent to the rapid filter 44 through the pipe 43 by the rapid filter pump 41. The rapid filter pump 41 is electrically connected to a sequencer 49 described later.

  A pressure gauge 42 for measuring the water pressure in the pipe 43 is connected to the pipe 43. The pressure gauge 42 is electrically connected to a sequencer 49 (described later) via a signal line 50.

  The rapid filter 44 is a device for solid-liquid separation of fine activated carbon 33, suspended solids and the like in the water to be treated, and has a filtration layer 65. Moreover, it is preferable that the rapid filter 44 has a space for depositing the fine activated carbon 33. The rapid filter 44 has pipes 43 and 46 connected to the upper part and pipes 51 and 52 connected to the lower part. The pipe 43 communicates with the first pit water tank 40, and the pipes 51 and 52 communicate with the second pit water tank 56.

  In the rapid filter 44, a filtration process for filtering the water to be treated and a backwashing process for backwashing the filtration layer 65 are alternately performed, and these are adjusted by a sequencer 49 described later. The filtration step and backwashing step will be described later.

  The pipe 46 is divided into two parts, and an automatic discharge valve 47 is provided on one side, and an automatic watering valve 48 is provided on the other side. The tip of the automatic discharge valve 47 is connected to the outside. The tip of the watering automatic valve 48 is connected to the watering pipe 24. The automatic discharge valve 47 and the automatic water spray valve 48 are electrically connected to a later-described sequencer 49 via a signal line 50, and the opening / closing thereof is adjusted by a signal from the sequencer 49.

  The second pit water tank 56 is a water tank for storing water to be treated which has been solid-liquid separated by the rapid filter 44. The second pit water tank 56 is provided with a pump 54 for pumping up the water to be treated, and the water to be treated is sent to the next process through the pipe 55 by the pump 54. Examples of the next step include a step of discharging to the natural world, a transfer to an activated carbon adsorption tower, and a transfer to an ion exchange resin tower.

  The second pit water tank 56 is provided with a rapid filter backwash pump (backwash means) 53 for pumping up the water to be treated. The rapid filter backwash pump 53 is a pump that transfers the water to be treated from the second pit water tank 56 to the rapid filter 44. The rapid filter backwash pump 53 is electrically connected to a sequencer 49 (described later) via a signal line 50.

  The sequencer 49 is connected to the pressure gauge 42 via the signal line 50 and periodically receives the water pressure value in the pipe 43. Moreover, it is electrically connected to the rapid filter pump 41, the rapid filter backwash pump 53, the discharge automatic valve 47 and the watering automatic valve 48 via the signal line 50, and by adjusting these, the above-described filtration process is performed. The backwashing step and the fine activated carbon discharge step described later are switched.

  The adjustment method using the sequencer 49 will be described in detail below.

  First, the filtration process will be described. In the filtration step, the sequencer 49 operates the rapid filter pump 41 to transfer the water to be treated from the first pit water tank 40 to the rapid filter 44. On the other hand, the rapid filter backwash pump 53 is stopped, and the automatic discharge valve 47 and the automatic water spray valve 48 are closed.

  As a result, the treated water flows from the first pit water tank 40 through the pipe 43 into the rapid filter 44, and the treated water flows from the upper side to the lower side of the filtration layer, in other words, from the upstream side to the downstream side in the filtration direction. It flows to. As a result, the fine activated carbon 33 contained in the water to be treated is deposited on the upper part of the filtration layer 65, and the fine activated carbon layer 45 is formed. The treated water that has passed through the filtration layer is transferred to the second pit water tank 56 through the pipe 51.

  The sequencer 49 periodically receives the water pressure value in the pipe 43 from the pressure gauge 42 via the signal line 50. When the water pressure value in the pipe 43 shows a certain value or more, the sequencer 49 stops the filtration process and switches to the backwash process.

  The water pressure value in the pipe 43 increases as the fine activated carbon layer 45 in the rapid filter 44 becomes thicker. Therefore, it is preferable to set the constant value to a water pressure value corresponding to the time when an appropriate amount of fine activated carbon 33 is deposited on the fine activated carbon layer 45.

  Next, the backwash process will be described. In the backwashing process, the sequencer 49 stops the rapid filter pump 41, opens the watering automatic valve 48, and operates the rapid filter backwash pump 53. Note that the automatic discharge valve 47 remains closed.

  As a result, the treated water flows from the second pit water tank 56 into the rapid filter 44 through the pipe 52, and the treated water flows from the lower side to the upper side of the filtration layer, in other words, from the downstream side in the filtration direction to the upstream side. To the side, it flows in the opposite direction to the filtration process. As a result, the water to be treated is backwashed by the rapid filter 44, becomes backwashed water containing the fine activated carbon 33 deposited on the fine activated carbon layer 45, and flows out to the pipe (fine activated carbon transfer means) 46.

  The backwash water that has flowed out to the pipe 46 passes through the open watering automatic valve 48 and is led to the watering pipe (fine activated carbon transfer means) 24 in the gas adsorption unit 18, and from the watering nozzle 27 to the gas adsorption unit 18. Water is sprinkled inside. As a result, the fine activated carbon 33 contained in the backwash water is introduced into the gas adsorption unit 18.

  After the rapid filter 44 is sufficiently backwashed, the backwashing process is stopped by the sequencer 49 and the filtration process is started. As a result, the fine activated carbon 33 starts to be newly deposited on the fine activated carbon layer 45 of the rapid filter 44.

  The switching between the filtration step and the backwashing step may be activated by a timer incorporated in the sequencer 49.

  In the present embodiment, the fine activated carbon 33 can be transferred from the decomposition unit 19 to the gas adsorption unit 18 by alternately performing the filtration step and the backwashing step. Moreover, since the rapid filter 44 can be wash | cleaned by performing a backwash process, a filtration process can be performed efficiently.

  The fine activated carbon 33 transferred to the gas adsorption unit 18 adheres to the plastic filler 22 and contributes to the adsorption treatment of the decomposition product gas 63. After the fine activated carbon 33 adheres to the plastic filler 22 for a certain period of time, it is replaced by the newly introduced fine activated carbon 33 and falls to the decomposition section 19 at the lower part.

  In the present embodiment, since the fine activated carbon 33 frequently flows out from the decomposition unit 19 to the first pit water tank 40, a lot of fine activated carbon 33 flows and accumulates in the rapid filter 44. Therefore, compared with the rapid filter in the conventional water treatment apparatus, in the rapid filter 44 of the present embodiment, the deposition rate of the deposit is high, so that the water pressure value in the pipe 43 increases rapidly. As a result, the frequency at which the filtration step and the backwashing step are switched increases. With such a configuration, the water treatment apparatus according to the present embodiment efficiently transfers the fine activated carbon 33 from the decomposition unit 19 to the gas adsorption unit 18, so that the fine activated carbon 33 can be efficiently reused.

  In the present embodiment, the fine activated carbon 33 adsorbs a substance to be decomposed such as an organic fluorine compound in the decomposition unit 19, contributes to the decomposition by nanobubbles, and then flows out together with the water to be treated. Has been deposited. Thereafter, the rapid filter 44 is backwashed to the pipe 46 together with the backwash water, passed through the watering automatic valve 48, led to the watering pipe 24, and sprinkled into the gas adsorbing unit 18. After being sprayed, it adheres to the plastic filler 22 and contributes to the adsorption treatment of the decomposed gas 63 generated from the substance to be decomposed such as an organic fluorine compound. The newly activated fine activated carbon 33 is replaced by the new backwash water sprinkled from the water spray nozzle 27, and the fine activated carbon 33 drops from the plastic filler 22 to the decomposition section 19 and operates as described above. repeat.

  After repeating the above cycle several times, the fine activated carbon 33 breaks through. If the ratio of the fine activated carbon 33 that has passed through increases, the adsorption treatment capacity of the decomposition products in the gas adsorbing portion 18 is significantly reduced, and a large amount of decomposition products that are not processed is contained in the exhaust gas 26.

  When the amount of decomposition products remaining in the exhaust gas 26 increases, the sequencer 49 performs a fine activated carbon discharging step.

  Next, the fine activated carbon discharging step will be described.

  In the fine activated carbon discharging step, the sequencer 49 stops the rapid filter pump 41, closes the watering automatic valve 48, opens the discharge automatic valve 47, and operates the rapid filter backwash pump 53. As a result, the backwash water containing the fine activated carbon 33 passes through the piping 46 and then passes through the automatic discharge valve 47 and is discharged to the outside.

  The fine activated carbon discharging step is preferably performed when the decomposition gas adsorption capacity of the gas adsorption unit 18 is significantly reduced. The frequency is preferably adjusted according to the quality of the water to be treated.

  When the fine activated carbon 33 is discharged to the outside, the total amount of the fine activated carbon 33 in the water treatment apparatus decreases, so that it is preferable to introduce new activated carbon 31 from the activated carbon inlet 62 as appropriate. The newly charged activated carbon 31 is crushed by aeration in the decomposition unit 19 to become fine activated carbon 33.

(Nano bubble generator 16)
The nanobubble generator 16 will be described in detail with reference to FIG.

  As shown in FIG. 1, the nanobubble generator 16 includes a first gas shearing unit 6, a second gas shearing unit 8, a third gas shearing unit 12, an electric needle valve (gas amount adjusting means) 11, a first pipe 4, The second pipe 7, the third pipe 10, and the fourth pipe 9 are configured.

  The first gas shearing part 6 will be described in detail below.

  In the 1st gas shearing part 6, microbubble containing water is created from gas and a liquid.

  In the present specification, the term “microbubble” refers to a bubble having a diameter of 10 μm to several tens of μm at the time of generation, and changes to micro / nanobubble by contraction movement after the generation. Further, “micronano bubbles” are bubbles having a diameter of several hundred nm to 10 μm, and “nano bubbles” are bubbles having a diameter of several hundred nm or less.

  As shown in FIG. 1, a first pipe 4, a second pipe 7, and a third pipe 10 are connected to the first gas shearing section 6. The first gas shearing unit 6 is provided with a gas-liquid mixing circulation pump 5.

  The gas-liquid mixing circulation pump 5 is a pump that supplies liquid to the first gas shearing unit 6 via the first pipe 4.

Although it does not specifically limit as the gas-liquid mixing circulation pump 5, It is preferable that it is a pump with a high head of 40 m or more (pressure of 4 kg / cm < ² >). The gas-liquid mixing circulation pump 5 is preferably a two-pole pump with stable torque. According to the said structure, it is possible to apply a desired pressure with respect to the microbubble containing water in the 1st gas shearing part 6, As a result, the microbubble contained in microbubble containing water is sheared more finely be able to.

  Moreover, in the gas-liquid mixing circulation pump 5, it is preferable that the pressure of the pump is controlled. For example, it is preferable that the rotation speed of the gas-liquid mixing circulation pump 5 is controlled by a rotation control unit (not shown) such as an inverter. The rotation control unit can be further controlled by a sequencer (not shown). According to the said structure, it becomes possible to apply a desired pressure with respect to the microbubble containing water in the said 1st gas shearing part 6, As a result, the microbubble contained in microbubble containing water is made into a desired size. Can be aligned.

  Although it does not specifically limit as a liquid supplied to the 1st gas shearing part 6, For example, it is preferable to use the to-be-processed water in the nanobubble generation water tank 15. FIG. If it is the said structure, the water treatment apparatus of this embodiment can be designed small.

  In addition, gas is supplied to the first gas shearing part 6 through the third pipe 10.

  When connecting the 3rd piping 10 to the 1st gas shearing part 6, the connection position of the 3rd piping 10 on the 1st gas shearing part 6, the connection angle of the 3rd piping 10 to the 1st gas shearing part 6, etc. Is not particularly limited. For example, the third pipe 10 is connected to the side surface of the first gas shearing portion 6 and to the inner side surface of the first gas shearing portion 6 (in other words, tangent to the inner surface of the first gas shearing portion 6). It is preferable that they are connected so as to form an angle of approximately 18 degrees.

  In order to efficiently produce microbubbles in the first gas shearing section, it is necessary to efficiently shear the gas. At this time, the liquid is rotated at an extremely high speed to form a negative pressure portion, and a gas is introduced into the negative pressure portion. The “negative pressure part” means a region where the pressure is smaller than that of the surroundings in the mixture of gas and liquid. The gas is efficiently sheared by the difference in rotational speed between the gas and the liquid. In this case, when the connection angle is 18 degrees, the shearing efficiency of the gas is the highest, so that the largest number of microbubbles can be produced.

  The supply of the gas into the first gas shearing unit 6 and the adjustment of the supply amount of the gas can be adjusted by opening and closing the electric needle valve 11 connected to the tip of the third pipe 10.

  Although it does not specifically limit as gas supplied to the 1st gas shearing part 6, For example, it is preferable that they are air, ozone, or oxygen, and it is more preferable that they are ozone or oxygen. By using ozone or oxygen, a larger amount of radicals can be generated than when air is used, so that the hardly decomposable compound can be oxidatively decomposed more effectively. In addition, when using ozone or oxygen, it is preferable to provide the tank which can store each gas at the terminal of the electric needle valve 11. In addition, it does not specifically limit as a specific structure of the said tank, It is possible to use a well-known tank suitably.

  The timing of the opening / closing operation of the electric needle valve 11 is not particularly limited. For example, first, the operation of the gas-liquid mixing circulation pump 5 is started to introduce the liquid into the first gas shearing section 6 and to stir the liquid. After that, it is preferable to open the electric needle valve 11 after the time when the output of the gas-liquid mixing circulation pump 5 reaches the maximum value, thereby supplying the gas into the first gas shearing section 6. Further, it is more preferable to open the electric needle valve 11 after 60 seconds from the start of the operation of the gas-liquid mixing circulation pump 5, thereby supplying gas into the first gas shearing section 6.

  Although it is possible to open the electric needle valve 11 at the start of operation of the gas-liquid mixing circulation pump 5, in this case, the gas-liquid mixing circulation pump 5 causes a cavitation phenomenon, and as a result, the gas-liquid mixing circulation pump 5 is damaged. There is a fear. However, as described above, if the gas is first introduced after the liquid is introduced, the gas-liquid mixing and circulation pump 5 can be prevented from causing the cavitation phenomenon. It is possible to prevent 5 from being damaged.

  The amount of gas supplied into the first gas shearing part 6 by opening the electric needle valve 11 is not particularly limited. For example, the gas is preferably supplied to the first gas shearing portion 6 at a rate of 1.2 liters / minute or less. If it is the said structure, a lot of nanobubble containing water can be produced finally.

  Thereafter, the liquid and the gas are mixed and sheared in the first gas shearing section 6, and as a result, microbubble-containing water is produced, and the microbubbles are supplied to the second gas shearing section via the second pipe 7. The contained water is discharged.

  Although the material of the 1st gas shearing part 6 is not specifically limited, It is preferable that they are stainless steel, a plastics, or resin. Of the above materials, stainless steel is most preferred. According to the said structure, while being able to prevent an impurity from mixing in microbubble containing water, it can prevent that the 1st gas shearing part 6 vibrates.

  Moreover, although the thickness (thickness of a partition) of the said 1st gas shearing part 6 is not specifically limited, It is preferable that they are 6 mm-12 mm. Generally, if the thickness of the first gas shearing part 6 is thin, the first gas shearing part 6 vibrates due to the movement of the microbubble-containing water in the first gas shearing part 6. That is, since the kinetic energy of the microbubble-containing water propagates to the outside as vibration and is lost, the high-speed flow motion of the microbubble-containing water decreases, and as a result, the shear energy decreases. However, according to the said structure, since the vibration of the 1st gas shearing part 6 can be prevented, a microbubble can be produced efficiently.

  The shape of the cross section of the inner cavity of the first gas shearing part 6 is not particularly limited, but is preferably an ellipse, and most preferably a perfect circle. Moreover, it is preferable that the lumen | bore surface of the said 1st gas shear part 6 is formed by mirror surface finishing. According to the said structure, since the friction of the internal surface of the 1st gas shearing part 6 is small, while being able to rotate the mixture of gas and liquid at high speed, gas can be sheared efficiently. As a result, many fine microbubbles can be generated, and finally many nanobubbles can be generated.

  Moreover, it is preferable that a groove is provided on the inner surface (lumen surface) of the first gas shearing portion 6. Further, the number of the grooves is not particularly limited, but two or more grooves are preferably provided. Moreover, the said groove | channel should just have a concave shape formed on the internal surface of the 1st gas shearing part 6, The shape is not specifically limited. For example, the groove preferably has a depth of approximately 0.3 mm to 0.6 mm and a width of approximately 0.8 mm or less. According to the above configuration, the generation of the swirling turbulent flow of the mixture of the liquid and gas in the first gas shearing section 6 can be controlled, so that many fine microbubbles can be generated and finally Many nanobubbles can be generated.

  Further, liquid is supplied to the first gas shearing section 6 through the first pipe 4, and microbubble-containing water is discharged through the second pipe 7. At this time, the area of the cross section of the lumen of the first pipe 4 for supplying the liquid is preferably larger than the area of the cross section of the lumen of the second pipe 7 for discharging the microbubble-containing water. According to the said structure, since the discharge pressure of microbubble containing water can be raised, a microbubble can be generated stably.

  The mechanism for producing microbubble-containing water in the first gas shearing section 6 will be described in more detail.

  In the first gas shearing unit 6, the pressure of the mixture of gas and liquid is controlled hydrodynamically using the gas-liquid mixing circulation pump 5, and gas is sucked into the negative pressure unit. Then, fine microbubbles are generated by shearing the gas while moving the mixture at high speed to form a negative pressure portion. In other words, the liquid and the gas are effectively self-sufficiently mixed and pumped. Thereby, microbubble-containing water containing finer microbubbles can be formed.

  The mechanism by which the first gas shearing unit 6 having the gas-liquid mixing circulation pump 5 generates microbubbles will be described in more detail.

  First, in the said 1st gas shearing part 6, the mixed phase swirl | flow which consists of the liquid and gas which are the structural components of microbubble containing water is generated. Specifically, a wing called an impeller is rotated at an ultra high speed to generate a mixed phase swirl composed of a liquid and a gas. At this time, a gas cavity that swirls at a high speed is formed at the center of the first gas shearing portion 6.

  Next, the gas cavity is narrowed in a tornado shape by pressure to generate a rotating shear flow that swirls at a higher speed. At this time, gas is automatically supplied to the gas cavity using the negative pressure of the gas cavity. Then, the multiphase swirl is rotated while further cutting and crushing the microbubbles. In addition, the said cutting | disconnection and grinding | pulverization arises by the difference in the rotational speed of the gas-liquid two-phase fluid inside and outside the exit of the 1st gas shearing part 6. The difference in rotational speed is preferably 500 to 600 revolutions / second.

  That is, in the first gas shearing section 6, the gas-liquid mixing circulation pump 5 moves the microbubble-containing water at high speed fluid motion to form a negative pressure section and hydrodynamically control the pressure of the microbubble-containing water. The gas is supplied to the negative pressure part. As a result, the first gas shearing part 6 can generate microbubbles. In other words, the microbubble-containing water can be produced by using the gas-liquid mixing circulation pump 5 to pump the liquid and the gas while effectively self-supplying and mixing them.

  Next, the second gas shearing portion 8 and the third gas shearing portion 12 will be described in detail.

  The second gas shearing part 8 further shears the microbubble-containing water produced in the first gas shearing part 6 to produce nanobubble-containing water.

  Moreover, the 3rd gas shearing part 12 further shears the nanobubble containing water produced in the 2nd gas shearing part 8, and produces the nanobubble containing water containing many nanobubbles.

  The second gas shearing portion 8 and the third gas shearing portion 12 are preferably formed of stainless steel, plastic, or resin.

  Further, the shape of the cross section of the lumen of the second gas shearing portion 8 and the third gas shearing portion 12 is preferably an elliptical shape, and most preferably a perfect circle. According to the said structure, since the resistance (friction) of the internal surface of the 2nd gas shearing part 8 and the 3rd gas shearing part 12 is small, while being able to rotate microbubble containing water at high speed, microbubble containing water is efficient It can shear well and, as a result, many nanobubbles can be generated.

  Moreover, it is preferable that a small hole is opened in the second gas shearing portion 8 and the third gas shearing portion 12. The diameter of the opening of the small hole is not particularly limited, but is preferably 4 mm to 9 mm. According to the above configuration, the swirling motion of the bubble-containing water inside the second gas shearing portion 8 and the third gas shearing portion 12 can be controlled. That is, according to the said structure, generation | occurrence | production of the rotation turbulent flow inside the 2nd gas shear part 8 and the 3rd gas shear part 12 is controllable. As a result, nanobubbles can be stably generated by the second gas shearing portion 8 and the third gas shearing portion 12. The specific size of the small hole can also be determined by the pump maximum suction value, the motor output value, and the pump discharge pressure value.

  Finally, the nanobubble flow 13 is discharged into the water to be treated by the third gas shearing section 12.

  In the nanobubble generator 16 according to the present embodiment, the microbubble-containing water is pumped from the first gas shearing section 6 to the second gas shearing section 8 and further to the third gas shearing section 12 by the gas-liquid mixing circulation pump 5. Is done. When the microbubble-containing water is pumped from the first gas shearing section 6 to the second gas shearing section 8 and further to the third gas shearing section 12 through the pipe, the direction in which the microbubble-containing water is pumped It is preferable that the diameter of the pipe decreases gradually or stepwise. According to the above configuration, the microbubble-containing water can be thinned like a tornado while performing fluid motion at a higher speed. In other words, it is possible to generate a rotating shear flow that swirls at a higher speed. As a result, nanobubbles can be efficiently generated from microbubbles, and an ultra-high temperature extreme reaction field can be formed in nanobubble-containing water.

  When the above-mentioned extreme reaction field is formed, the water containing nanobubbles locally becomes a high-temperature and high-pressure state, and unstable free radicals are generated locally, and at the same time, heat is generated. A free radical is an atom or molecule having an unpaired electron, and attempts to stabilize by taking electrons from other atoms or molecules. Therefore, nanobubble-containing water containing free radicals exhibits a strong oxidizing power. Therefore, according to the said structure, organic substance etc. can be oxidatively decomposed | disassembled by the effect | action of a free radical.

Although it does not specifically limit as specific structures, such as the gas-liquid mixing circulation pump 5 mentioned above, the 1st gas shearing part 6, the 2nd gas shearing part 8, and the 3rd gas shearing part 12, For example, using a commercially available thing is used. Is possible. For example, it is possible to use a Bavidas HYK type manufactured by Kyowa Kikai Co., Ltd., but is not limited to this.
[Second Embodiment]
The following will describe another embodiment (second embodiment) of the present invention with reference to FIG.

  In the water treatment apparatus of the present embodiment, the plastic filler 22 provided in the gas adsorption unit 18 in the water treatment apparatus of the first embodiment is replaced with a ring-type polyvinylidene chloride 57. Only this point is different from the water treatment apparatus of the first embodiment. About the same part as the water treatment apparatus of 1st Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. Only parts different from the water treatment apparatus of the first embodiment will be described below.

  In the water treatment apparatus of this embodiment, the fine activated carbon 33 is attached to the ring-type polyvinylidene chloride 57 in the gas adsorption unit 18. Since the ring-type polyvinylidene chloride 57 is fibrous and has a large surface area, a large amount of fine activated carbon 33 can be attached. As a result, the decomposition product gas 63 can be efficiently adsorbed.

In addition, since the ring-type polyvinylidene chloride 57 is a filler used as a carrier for immobilizing microorganisms, in this embodiment, the microorganisms are propagated in the ring-type polyvinylidene chloride 57 to further decompose the decomposition product gas 63. You can also.
[Third Embodiment]
The following will describe another embodiment (third embodiment) of the present invention with reference to FIG.

  In the water treatment apparatus of this embodiment, the plastic filler 22 provided in the gas adsorption unit 18 in the water treatment apparatus of the first embodiment is replaced with a mesh block (mesh sheet) 61. Only this point is different from the water treatment apparatus of the first embodiment. About the same part as the water treatment apparatus of 1st Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. Only parts different from the water treatment apparatus of the first embodiment will be described below.

In the water treatment apparatus of the present embodiment, the fine activated carbon 33 is attached to the mesh block 61 in the gas adsorption unit 18. Since the mesh block 61 has a large surface area, a large amount of fine activated carbon 33 can be attached. As a result, the decomposition product gas 63 can be efficiently adsorbed. Further, since the mesh block 61 has a mesh structure, even if the fine activated carbon 33 adheres, the passage of the decomposition gas 63 is not blocked, and the blocking phenomenon does not occur. Therefore, the decomposition product gas 63 can be efficiently raised in the gas adsorption unit 18 and exhausted from the exhaust chimney 25 and removed.
[Fourth Embodiment]
The following will describe another embodiment (fourth embodiment) of the present invention with reference to FIG.

  The water treatment apparatus of this embodiment includes an activated carbon adsorption tower 58 connected to the second pit water tank 56 in the water treatment apparatus of the first embodiment by piping. Only this point is different from the water treatment apparatus of the first embodiment. About the same part as the water treatment apparatus of 1st Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. Only parts different from the water treatment apparatus of the first embodiment will be described below.

  In the water treatment apparatus of this embodiment, the water to be treated in the second pit water tank 56 is pumped up by the pump 54 and transferred to the activated carbon adsorption tower 58.

  In the activated carbon adsorption tower 58, the organic fluorine compound remaining in a minute amount in the water to be treated is subjected to an adsorption treatment. Thereby, the organic fluorine compound under treatment can be treated to a high degree. The treated water discharged from the activated carbon adsorption tower 58 is transferred to the water tank 59 and then discharged outside as treated (finished) water.

Although it does not specifically limit as activated carbon with which the activated carbon adsorption tower 58 is filled, For example, Kuraray Coal GW (made by Kuraray Chemical Co., Ltd.) etc. which are activated carbon for water treatment are mentioned.
[Fifth Embodiment]
The following will describe another embodiment (fifth embodiment) of the present invention with reference to FIG.

  The water treatment apparatus of the present embodiment includes an ion exchange resin tower 60 connected to the second pit water tank 56 in the water treatment apparatus of the first embodiment by piping. Only this point is different from the water treatment apparatus of the first embodiment. About the same part as the water treatment apparatus of 1st Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. Only parts different from the water treatment apparatus of the first embodiment will be described below.

  In the water treatment apparatus of this embodiment, the water to be treated in the second pit water tank 56 is pumped up by the pump 54 and transferred to the ion exchange resin tower 60. In the ion exchange resin tower 60, the organic fluorine compound which is ionized in the water to be treated can be selectively ion-exchanged for treatment. Thereby, the organic fluorine compound under treatment can be treated to a high degree. The ion exchange resin tower 60 can easily treat the ionized organic fluorine compound. For example, perfluorooctane sulfonic acid is dissolved in the liquid phase to form ions, and can be easily treated by the water treatment apparatus of this embodiment. The treated water discharged from the ion exchange resin tower 60 is transferred to the water tank 59 and then discharged outside as treated (finished) water.

Although it does not specifically limit as an ion exchange resin with which the ion exchange resin tower 60 is filled, For example, a diamond ion (made by Mitsubishi Chemical Corporation) etc. is mentioned.
[Sixth Embodiment]
The following will describe another embodiment (sixth embodiment) of the present invention with reference to FIG.

  In the water treatment apparatus of the present embodiment, there is no plastic filler 22 provided in the gas adsorption unit 18 in the water treatment apparatus of the first embodiment. Only this point is different from the water treatment apparatus of the first embodiment. About the same part as the water treatment apparatus of 1st Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. Only parts different from the water treatment apparatus of the first embodiment will be described below.

  In the water treatment apparatus of the present embodiment, since the gas adsorbing unit 18 is not provided with a filler, the fine activated carbon 33 sprinkled with the backwash water is decomposed in the gas adsorbing unit 18 in a watered state. The adsorption process of the product gas 63 is performed.

  In the water treatment apparatus of this embodiment, since the gas adsorber 18 is not provided with a filler, the initial cost can be reduced. When the concentration of a substance to be decomposed such as an organic fluorine compound contained in the water to be treated is low, the water treatment apparatus of this embodiment is preferably used.

  Based on 1st Embodiment of this invention, the continuous experiment apparatus used as a water treatment apparatus was produced.

  The water treatment apparatus in the present embodiment will be described below with reference to FIG.

The capacity of the raw water tank 2 is 0.5 m ³ , the capacity of the nanobubble generating water tank 15 is 0.1 m ³ , the capacity of the gas adsorbing part 18 at the upper part of the decomposition adsorption tank 20 is about 1.0 m ³ , and the lower part of the decomposition adsorption tank 20 The capacity of the decomposition unit 19 is about 0.7 m ³ , the capacity of the first pit water tank 40 is 0.1 m ³ , the capacity of the quick filter 44 is 0.2 m ³ , and the capacity of the second pit water tank 56 is 0.1 m. ^{It was set to 3} .

  In the nanobubble generation tank 15, as a nanobubble generator 16, a Bavidas HYK type manufactured by Kyowa Kikai Co., Ltd., in which the gas-liquid mixing circulation pump 5 is configured by an electric motor having an output of 3.7 kW, was used.

In the decomposition unit 19, “Kuraray Coal GW (registered trademark)” (manufactured by Kuraray Chemical Co., Ltd.), which is activated carbon for water treatment (for liquid phase), is used as the activated carbon 31 at 0.3 (cm ³ ) per volume of the decomposition unit 19. / Cm ³ ) was added. The amount of aerated air from the diffuser pipe 36 in the decomposition unit 19 was 50 m ³ / hour / m ³ per tank capacity. Therefore, when the water treatment apparatus in this example was operated, the activated carbon 31 was aerated and crushed in the decomposition unit 19 to become fine activated carbon 33, and the fine activated carbon 33 was supplied to the gas adsorption unit 18.

  The gas adsorbing part 18 was filled with polyethylene S-II type (manufactured by Tsukishima Environmental Engineering Co., Ltd.) as the plastic filler 22. The filling rate of the plastic filler 22 in the capacity of the gas adsorption unit 18 was 40%.

  In the raw water tank 2, organic fluorine compound-containing water containing PFOS having a concentration of 30 ppb was introduced.

  After the water treatment apparatus in this embodiment is operated, the PFOS concentration, the total fluorine concentration, and the sulfate ion concentration of the water to be treated stored in the raw water tank 2 and the second pit water tank 56 on the 12th day, respectively. Was measured. Further, with respect to the exhaust gas 26, the concentration of PFOS was measured, and a qualitative test of the decomposition product was performed.

  In addition, the density | concentration of PFOS which exists in to-be-processed water was measured by LC / MS / MS (liquid chromatograph-tandem type | mold mass spectrometer). Moreover, the concentration measurement of PFOS performed about the exhaust gas 26 and the qualitative test of the decomposition product were performed by GC-MS (gas chromatography mass spectrometry).

  The results of this example are shown in Tables 1 and 2. Table 1 shows the PFOS concentration, total fluorine concentration, and sulfate ion concentration in the treated water stored in the raw water tank 2 and the second pit water tank 56, respectively. Table 2 shows the exhaust gas 26, The PFOS concentration and the result of the qualitative test of the degradation product are shown.

  From Tables 1 and 2, the following a) to e) became clear.

  a) Since the concentration of PFOS in the second pit water tank 56 was clearly lower than that in the raw water tank 2, it became clear that the PFOS in the water to be treated was decomposed. The removal rate of PFOS was 91%.

  b) Since the total fluorine amount in the second pit water tank 56 was clearly lower than that in the raw water tank 2, the decomposition product of PFOS was gasified and transferred from the decomposition unit 19 to the gas adsorption unit 18. It became clear.

  c) Since sulfate ions were detected in the second pit water tank 56, it was revealed that PFOS in the water to be treated was decomposed and sulfate ions were liberated as part of the decomposition product.

  d) Since PFOS was not detected in the exhaust gas 26 at a high concentration, it became clear that the PFOS was not merely mist-like (mist) but scattered in the gas phase.

e) Since no decomposition products such as perfluorocarbon (CF ₃ (CF ₂ ) _n H, n = 3, 4, 5, 6) were detected in the exhaust gas 26, the decomposition product of gasified PFOS was gas It became clear that the fine activated carbon 33 was adsorbed in the adsorption part 18.

  As a comparative example of this example, a water treatment apparatus in which the activated carbon 31 was not added to the decomposition unit 19 was produced. In the water treatment apparatus of this comparative example, since the activated carbon 31 is not added to the decomposition unit 19, the fine activated carbon 33 is not generated, and therefore the fine activated carbon 33 is not supplied to the gas adsorption unit 18. In the water treatment apparatus of this comparative example, the configuration is the same as that of the present embodiment except that the activated carbon 31 is not added to the decomposition unit 19 and that the fine activated carbon 33 is generated from the activated carbon 31 and is not supplied to the gas adsorption unit 18. Therefore, detailed description is omitted.

  The results of this comparative example are shown in Table 3 and Table 4. Table 3 shows the PFOS concentration, total fluorine concentration, and sulfate ion concentration in the treated water stored in the raw water tank 2 and the second pit water tank 56 on the 12th day after the operation of the water treatment apparatus. Table 4 shows the PFOS concentration in the exhaust gas 26 and the result of the qualitative test of the decomposition product.

  From Table 3 and Table 4, the following a) to e) became clear.

  a) Since the concentration of PFOS in the second pit water tank 56 was lower than that in the raw water tank 2, it was clear that the PFOS in the water to be treated was decomposed even without the activated carbon 31, that is, only with nanobubbles. became. The removal rate of PFOS was 76%.

  b) Since the total amount of fluorine in the second pit water tank 56 was clearly lower than that in the raw water tank 2, the decomposition product of PFOS was gasified without the activated carbon 31, that is, only with nanobubbles, and the decomposition part It was revealed that the gas was transferred from 19 to the gas adsorption unit 18.

  c) Since sulfate ions were detected in the second pit water tank 56, it was revealed that PFOS in the water to be treated was decomposed and sulfate ions were liberated as part of the decomposition product.

  d) Since PFOS was not detected in the exhaust gas 26 at a high concentration, it became clear that the PFOS was not merely mist-like (mist) but scattered in the gas phase.

  e) In the exhaust gas 26, since decomposition products such as C5, C6, C7, and C8 perfluorocarbon were detected, it was clear that the gasified PFOS decomposition product was not adsorbed in the gas adsorption unit 18. became.

  From the comparison between the example and the comparative example, it was revealed that the removal rate of PFOS in the water to be treated is increased by adding the activated carbon 31 to the decomposition unit 19 in the water treatment apparatus according to the present embodiment. Further, it is clear that the activated carbon 31 is crushed by aeration to produce fine activated carbon 33 and further the fine activated carbon 33 is supplied to the gas adsorbing unit 18 so that the gasified PFOS decomposition product is efficiently adsorbed. became.

  Note that the present invention is not limited to the configurations described above, and various modifications are possible within the scope of the claims, and technical means disclosed in different embodiments and examples respectively. Embodiments and examples obtained by appropriately combining them are also included in the technical scope of the present invention.

  INDUSTRIAL APPLICABILITY The present invention can be used in the field of manufacturing water treatment apparatuses such as industrial water, agricultural water, and domestic water, and wastewater treatment apparatuses such as industrial wastewater, agricultural wastewater, and domestic wastewater.

It is a schematic diagram which shows one Embodiment (1st Embodiment) of the water treatment apparatus in this invention. It is a schematic diagram which shows one Embodiment (2nd Embodiment) of the water treatment apparatus in this invention. It is a schematic diagram which shows one Embodiment (3rd Embodiment) of the water treatment apparatus in this invention. It is a schematic diagram which shows one Embodiment (4th Embodiment) of the water treatment apparatus in this invention. It is a schematic diagram which shows one Embodiment (5th Embodiment) of the water treatment apparatus in this invention. It is a schematic diagram which shows one Embodiment (6th Embodiment) of the water treatment apparatus in this invention.

Explanation of symbols

2 Raw water tank 4 1st piping 5 Gas-liquid mixing circulation pump 6 1st gas shearing part 7 2nd piping 8 2nd gas shearing part 9 4th piping 10 3rd piping 11 Electric needle valve (gas amount adjustment means)
12 3rd gas shearing part 15 Nano bubble generation water tank 16 Nano bubble generator (nano bubble generation means)
17 Overflow water piping (Treatment water transfer means)
18 Gas adsorption part 19 Decomposition part 20 Decomposition adsorption tank 22 Plastic filler 24 Sprinkling piping (fine activated carbon transfer means)
30 Nano bubble 31 Activated carbon 32 Overflow plate 33 Fine activated carbon 34 Side wall (side surface)
36 Air diffuser (aeration means)
40 First pit tank 44 Rapid filter 46 Piping (fine activated carbon transfer means)
53 Rapid filter backwash pump (backwash means)
56 Second pit water tank 57 Ring-type polyvinylidene chloride 58 Activated carbon adsorption tower 60 Ion exchange resin tower 61 Reticulated block (reticulated sheet)
64 outlet

Claims (28)

Nanobubble generating means for generating nanobubbles in the water to be treated;
A decomposition unit that stores the water to be treated containing the nanobubbles, and a decomposition adsorption tank that is a space into which gas generated from the decomposition unit is introduced and includes a gas adsorption unit in which fine activated carbon is placed; ,
A water treatment apparatus comprising: aeration means for aeration of the treated water stored in the decomposition unit.   The water treatment apparatus according to claim 1, wherein the water to be treated contains an organic fluorine compound. Activated carbon is put in the decomposition part,
The water treatment apparatus according to claim 1 or 2, wherein the fine activated carbon is fine activated carbon produced by aeration and crushing of the activated carbon by the aeration means. A rapid filter for filtering the water to be treated in the decomposition section;
The water treatment apparatus according to claim 3, further comprising fine activated carbon transfer means for transferring the fine activated carbon separated in the rapid filter to the gas adsorption unit. Further equipped with backwashing means for backwashing the rapid filter,
5. The water treatment according to claim 4, wherein the fine activated carbon transfer means transfers the fine activated carbon separated in the rapid filter to a gas adsorbing portion by backwash water discharged from the backwash means. apparatus.   The water treatment apparatus according to claim 5, wherein the fine activated carbon transfer means further includes an automatic valve for removing the broken fine activated carbon contained in the backwash water.   The water treatment apparatus according to any one of claims 4 to 6, wherein the rapid filter has a space for depositing the fine activated carbon. The disassembly part is
A side surface inclined so that the cross-sectional area in the horizontal direction increases toward the top,
An outlet provided in the side surface;
The water treatment apparatus according to any one of claims 3 to 7, further comprising an overflow plate provided so that activated carbon larger than the fine activated carbon does not flow out of the discharge port.   The water treatment apparatus according to any one of claims 1 to 8, wherein the gas adsorption unit includes a filler for adhering the fine activated carbon.   The water treatment apparatus according to claim 9, wherein the filler is made of plastic.   The water treatment apparatus according to claim 10, wherein the filler is made of ring-type polyvinylidene chloride.   The water treatment apparatus according to claim 9 or 10, wherein the filler is a mesh sheet. A nanobubble generation tank for storing the treated water;
A water to be treated transfer means for transferring the water to be treated from the nanobubble generation water tank to the decomposition adsorption tank;
The water treatment device according to any one of claims 1 to 12, wherein the nanobubble generating means generates the nanobubbles in the water to be treated stored in the nanobubble generating water tank. The nanobubble generating means is:
A first gas shearing section that mixes and shears liquid and gas to produce microbubble-containing water;
A second gas shearing section for further shearing the microbubble-containing water to produce nanobubble-containing water;
The water treatment according to any one of claims 1 to 13, further comprising: a third gas shearing unit that further shears the nanobubble-containing water to produce nanobubble-containing water containing a large amount of nanobubbles. apparatus. The cross section inside the first gas shearing part is elliptical or true circular,
The water treatment apparatus according to claim 14, wherein two or more grooves are provided on an inner surface of the first gas shearing part. The depth of the groove is 0.3 mm to 0.6 mm,
The water treatment apparatus according to claim 14, wherein the width of the groove is 0.8 mm or less. In the first gas shearing section, the liquid is supplied through the first pipe and the microbubble-containing water is discharged through the second pipe.
The water treatment device according to any one of claims 14 to 16, wherein an area of a cross section of the lumen of the first pipe is larger than an area of a cross section of the lumen of the second pipe. . The nanobubble generating means is:
A gas-liquid mixing circulation pump for supplying a liquid to the first gas shearing section and mixing and circulating the liquid and the gas;
A third pipe for supplying gas to the first gas shearing section;
The water treatment device according to any one of claims 14 to 17, further comprising: a gas amount adjusting unit that adjusts an amount of gas supplied to the first gas shearing unit.   The water treatment apparatus according to claim 18, wherein the gas amount adjusting means supplies the gas at a rate of 1.2 liter / min or less to the first gas shearing part.   The water treatment device according to claim 18 or 19, wherein the gas is taken into the first gas shearing section after the time when the output of the gas-liquid mixing circulation pump reaches a maximum value.   The water treatment apparatus according to claim 18 or 19, wherein the gas is taken into the first gas shearing section after 60 seconds from the start of the operation of the gas-liquid mixing circulation pump.   The said 3rd piping is connected to the said 1st gas shear part so that the angle of 18 degree | times may be made with respect to the inner surface of the said 1st gas shear part, The any one of Claims 18-21 characterized by the above-mentioned. The water treatment apparatus of Claim 1.   The water treatment device according to any one of claims 14 to 22, wherein a thickness of the partition wall of the first gas shearing portion is 6 mm to 12 mm.   The water treatment apparatus according to any one of claims 1 to 23, further comprising an activated carbon adsorption tower activated carbon adsorption tower that performs adsorption treatment of the water to be treated filtered in the rapid filter.   The water treatment apparatus according to any one of claims 1 to 24, further comprising an ion exchange resin tower that performs adsorption treatment of the water to be treated filtered in the rapid filter.   The water treatment apparatus according to any one of claims 1 to 25, wherein the fine activated carbon has an average particle size of 0.2 mm or less. A water treatment method for treating water to be treated containing an organic fluorine compound,
Nano bubbles and activated carbon are added to the water to be treated,
A water treatment method, wherein the organic fluorine compound is decomposed and adsorbed by the oxidizing power of nanobubbles and the adsorption action of activated carbon.   The organic fluorine compound is one or more organic fluorine compounds selected from the group consisting of perfluorooctanesulfonic acid, perfluorooctanoic acid, perfluoroalkylsulfonic acid, perfluorooctanesulfonic acid fluoride, and perfluorooctanesulfonic acid fluoride derivatives. The water treatment method according to claim 27, wherein:

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