JP2001225060A - Water treatment method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water treatment method and a device therefor, capable of reducing the load of a biological treatment means in a post-process and of easily performing coagulative separation of dissolved substances, to which constrained water is bonded by intermolecular force, without using a coagulating agent causing an environmental problem. SOLUTION: Wastewater treatment is carried out in a state adding two means to an aqueous solution, wherein one of means breaks or separates the constrained water bonded to water-soluble dissolved substances by the intermolecular force, and the other of means prevents the constrained water from being reconstrained. The means for preventing the reconstraint of the constrained water consists of fine air bubbles having a diameter of 10 μm or less. The means for breaking or separating the constrained water consists of a high frequency of 10 MHz to 1 GHz, ultrasonic waves having peak values in plural frequency bands or 0.1 mol/l or more of chloride ions, fine air bubbles having a diameter of 10 μm or less, or their combination.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to solid matter, microorganisms,
Organic compounds dissolved in aqueous solutions as well as organic compounds,
The present invention relates to a water treatment method and a water treatment method capable of positively removing or concentrating phosphorus-based and nitrogen-based solutes, and in particular, sewerage treatment equipment, human waste treatment equipment, livestock wastewater treatment equipment, fishery processing wastewater treatment equipment, Applicable to food processing wastewater treatment equipment, washing wastewater treatment equipment, factory wastewater treatment equipment, lake water purification equipment, etc., a processing method for positively removing the dissolved substances contained in wastewater and purifying water, The present invention relates to a water treatment method applied to a process for concentrating and purifying dissolved substances from an aqueous solution and an apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, as a sewage wastewater treatment method, a pressurized flotation separation method and an activated sludge treatment method using microorganisms have been dominant. FIG. 13 shows such a conventional pressure-flotation / separation apparatus, in which 101 denotes a wastewater treatment tank by a pressure-flotation method. In the pressurized flotation method, a part of the water extracted from the wastewater treatment tank 101 is supplied to the pressurized tank 103 by the pump 104,
Air is pressurized and dissolved by the compressor 202 in the pressurized tank 103 to generate pressurized water, and the pressurized water is supplied from the lower part of the wastewater treatment tank 101. At this time, when the pressure of the pressurized water is released in the wastewater treatment tank 101, the air dissolved in the pressurized water is generated as fine bubbles. A method of purifying the wastewater by utilizing the fact that the air bubbles adsorb with the suspended suspended matter present in the wastewater and the suspended suspended matter floats together with the air bubbles on the upper part of the wastewater treatment tank 101 by the buoyancy of the air bubbles. is there. The suspended material that has floated is sent to a sludge treatment step.

However, in the pressure flotation method, only bubbles larger than 10 μm can be formed at present, and so-called solid-liquid separation is possible, but solute dissolved in water cannot be separated. That is, when air is dissolved in water under pressure and then released to the atmosphere, fine bubbles are generated. Since the bubbles are larger than 10 μm, they tend to be generated at a discontinuous interface between a liquid and a solid. . That is, the adhesive force between a suspended substance in water and air bubbles depends on the interfacial tension acting on the contact interface between the substance and water and air. In general, a hydrophobic interface is more likely to adhere to air than a hydrophilic interface. Power is great. For this reason, in the pressure flotation method, the hydrophilic substance dissolved in water, in other words, the solute substance to which bound water is bound by intermolecular force cannot be removed, and the state in which the substance is simply mixed in water cannot be removed. Only suspended suspended solids could be removed.

Therefore, according to the prior art, the treatment of fine particles, organic compounds, solutes, etc., which could not be removed by the pressure flotation method or the like, as shown in FIG. Activated sludge treatment tank 102
And activated sludge treatment by microorganisms is used.

[0005]

As described above, the current pressurized flotation method can only remove large suspended solids, and BOD (biochemical oxygen consumption), COD (chemical The amount of fine particles, organic compounds, solutes, etc., which are the causes of oxygen consumption) and SS (floating suspended solids). For this reason, the pressure flotation method may be used after adding a flocculant in advance and solidifying to a large suspended substance, but from the viewpoint of environmental conservation, it is desirable that the flocculant is not used as much as possible, and management is troublesome. .

For this reason, the pressurized flotation method and the activated sludge method are currently combined, but the activated sludge method uses microorganisms, so that the treatment capacity is slow and the apparatus must be enlarged. In addition, there is a problem that it takes time and effort for maintenance because microorganisms are targets. Furthermore, disposal of residual activated sludge discharged after treatment has become a social problem due to shortage of final disposal sites and the like, and development of a treatment method that generates as little excess activated sludge as possible is desired.

In view of the above technical problems, the present invention reduces the load on biological treatment means in the post-process, and binds bound water by intermolecular force without using an environmentally problematic flocculant. An object of the present invention is to provide a water treatment method and a water treatment method capable of easily coagulating and separating a solute substance. The present invention also provides a water treatment method and apparatus capable of positively removing not only solids, microorganisms, organic compounds, but also organic, phosphorus, and nitrogen-based solutes dissolved in an aqueous solution. To provide, especially, sewage treatment equipment, human waste treatment equipment,
Water that can be applied to livestock wastewater treatment equipment, marine processing wastewater treatment equipment, food processing wastewater treatment equipment, washing wastewater treatment equipment, factory wastewater treatment equipment, lake water purification equipment, etc., and also to the process of concentrating and purifying dissolved substances from aqueous solutions An object of the present invention is to provide a processing method and an apparatus therefor.

[0008]

The process leading to the present invention will be described step by step. For example, in a wastewater treatment method, fine solids, microorganisms, and substances such as organic, phosphoric, and solute substances that are present in the wastewater and are to be removed have a lower dielectric constant than water. And, since an attractive force acts in the aqueous solution between the dielectric substances smaller than water, if bubbles having a small dielectric constant are formed in the wastewater, the solids and the like present in the wastewater are adsorbed by the bubbles. The same applies to the pressure flotation method in which solids can be separated by removing the bubbles by coagulation.

Next, the mechanism by which a substance having a dielectric constant smaller than that of water is adsorbed on the bubbles will be described. The substance dissolved in the aqueous solution is referred to as particles 1 and the bubbles are referred to as particles 2. er is the relative dielectric constant of the aqueous solution, er1 is the relative dielectric constant of particle 1, er2 is the relative dielectric constant of particle 2, a1 is the radius of particle 1, a2 is the radius of particle 2, and r is the distance between particles 1 and 2. , K is the Boltzmann constant and T is the temperature of the aqueous solution, it is known as a known fact that the polarization interaction energy W (r) between the particles 1 and 2 can be expressed by the following equation (1). Intermediate force and surface force (second edition), by Israeli Avili, Asakura Shoten, 1986.

(Equation 1)

The relative permittivity er of water is 78.3 (25 ° C.),
The relative permittivity er2 of the bubbles of the particles 2 is about 1. on the other hand,
The relative dielectric constant of an organic compound to be treated for wastewater is er1 of 10 or less (edited by The Chemical Society of Japan: Basic Handbook of Chemical Handbook)
II, p. 506). Therefore, for a substance such as an organic compound, the polarization interaction energy W
The sign of (r) is negative, indicating that an attractive force acts between the organic compound and the bubbles. On the other hand, not only organic compounds but also nitrogen compounds such as ammonia and phosphorus-based compounds are generally hydrated and often dissolved in an aqueous solution, and around these solutes, water molecules called bound water are present. Are connected by an intermolecular force.

[0011] Therefore, simply bubbling bubbles in the wastewater does not allow coagulation and separation of solutes and organic substances to which bound water is bound. That is, the bound water, unlike free water, is restricted in movement by a solute substance, and therefore cannot bind without first breaking or separating bound water bound to the solute, and further bound to the solute. After the constrained water is broken or separated, it is difficult to coagulate and separate the solute from the aqueous solution unless the solute is provided with a means for inhibiting the reconstraint of the constrained water.

Therefore, the present invention has found that the means for inhibiting the re-constraint of the confined water is a group of microbubbles having a diameter of 10 μm or less. Further, as means for destroying or separating the confined water, a frequency of 10 MHz to 1 GHz is used. It has been found that they are high-frequency waves, ultrasonic waves having peak values in a plurality of frequency ranges, chloride ions of 0.1 mol / liter or more, a group of fine bubbles having a diameter of 10 μm or less, or a combination thereof.

[0013] The invention of claim 1 focuses on this point, and in the water treatment method for separating the solute from an aqueous solution containing the solute bound to the bound water by an intermolecular force, A water treatment method characterized by destroying or separating the bound water bound to the solute and coagulating and separating the solute from the aqueous solution while providing the solute with a means for inhibiting the rebound of the bound water. I do.

The invention according to claim 2 is particularly applied to a wastewater treatment method for coagulating and separating nitrogen, phosphorus or an organic water-soluble solution from an aqueous solution, and is bonded to the water-soluble solution by an intermolecular force. The method is characterized in that the dissolved substance is coagulated and separated from the aqueous solution while providing means for breaking or separating the bound water and inhibiting re-binding of the bound water.

The invention is also applied to a method for concentrating a solute. That is, the invention according to claim 3 is a water treatment method for concentrating a dissolved substance from an aqueous solution, in which the bound water bound to the water-soluble dissolved substance by an intermolecular force is destroyed or separated, and the bound water is separated. The solution is concentrated while providing a means for inhibiting re-restraint in the aqueous solution.

The present invention will be specifically described. As shown in the above formula (1), the smaller the radius a2 of the bubbles in the drainage water,
It can also be seen that the attraction increases. When comparing the case of the bubble having a bubble diameter of 100 μm, the bubble of 10 μm, and the bubble of 1 μm, the bubble of 10 μm has 1000 times stronger adsorption power than the bubble of 100 μm, and in the case of the bubble of 1 μm A million times stronger adsorption power. From this, if fine bubbles are formed in the aqueous solution that destroy the bound water and hinder the re-bound of the bound water, a substance having a relative dielectric constant smaller than water, such as an organic compound, is formed around the bubbles. It is possible to aggregate in the state of being attracted to and adsorbed. Therefore, if fine bubbles of 10 μm or less can be formed in the aqueous solution, it is possible in principle to cause the bubbles to aggregate the organic compound and the like while adsorbing them. In the present invention, paying attention to this point, if a group of fine bubbles of 10 μm or less is adsorbed with the dissolved substance and the dissolved substance adsorbed together with the group of bubbles is coagulated and separated, it can be removed by the conventional pressure flotation method. Instead, fine solids that had been treated by the activated sludge treatment method in the subsequent process,
It has been found that microorganisms, organic compounds and solutes can be removed.

That is, according to the present invention, if fine bubbles are formed in wastewater, not only microorganisms existing in the wastewater but which could not be removed by the conventional pressure flotation method, but also organic compounds, nitrogen, phosphoric acid and the like can be used. The solute substance can be adsorbed against the confined water and removed by aggregation.

Along with a bubble group containing fine bubbles having a diameter of 10 μm or less, a high frequency of 10 MHz to 1 GHz, ultrasonic waves having peak values in a plurality of frequency ranges, or chloride ions of 0.1 mol / liter or more, or a combination thereof. And effective.

The reason for this is that fine bubbles of 10 μm or less adsorb to fine solids, microorganisms, organic compounds, and solutes in the wastewater, but because of the small size of the bubbles, the bubbles have a small buoyancy and float. Although it takes time, the bubbles are moved by sound pressure using compression waves or high frequencies of ultrasonic waves, whereby the dissolved substance adsorbed on the bubbles can be efficiently concentrated and separated. And in this case, the high frequency is
A high frequency in the frequency range of 10 MHz to 1 GHz is preferable, and the ultrasonic wave is preferably an ultrasonic wave which combines a standing wave and a traveling wave and has peak values in a plurality of frequency ranges. Even without using such physical means, fine bubbles may be generated in a state containing 0.1 mol / liter or more of chloride ions.

According to a sixth aspect of the present invention, as means for generating a bubble group including fine bubbles having a diameter of 10 μm or less,
It is characterized in that fine bubbles are generated by cavitation caused by application of ultrasonic waves. That is, very fine bubbles are formed by cavitation, and the bubbles are collected and aggregated by the sound pressure of the ultrasonic wave.

Further, as means for generating fine bubbles in a state containing chloride ions of 0.1 mol / liter or more, the inventions according to claims 7 to 9 are proposed. In other words, the invention according to claim 7 is a method of generating a bubble group containing fine bubbles having a diameter of 10 μm or less, by treating an aqueous solution containing 0.1 mol / L or more of chloride ions with the aqueous solution. Air is blown into the aqueous solution containing chloride ions through a filter plate while supplying the solution into the inside of the water treatment section to form bubbles in the water treatment section.

According to the present invention, as means for generating a bubble group including fine bubbles having a diameter of 10 μm or less,
An electrode plate was provided in the water treatment section of the aqueous solution, and 0.1 mol /
While supplying an aqueous solution containing liters or more of chloride ions between the electrode plates, a voltage is applied to the electrode plates to cause electrolysis to form bubbles.

Further, the invention according to claim 9 has a diameter of 10 μm.
As means for generating a bubble group containing the following fine bubbles, pressurized water obtained by pressurizing and dissolving air in an aqueous solution containing 0.1 mol / L or more of chloride ions is supplied into a water treatment section of the aqueous solution. In addition, a bubble group is formed by a pressure flotation method.

Each of the above-mentioned inventions is based on the fact that fine bubbles containing a large amount of bubbles of 10 μm or less are contained in an aqueous solution in which chloride ions of 0.1 mol / liter or more coexist, by utilizing the fact that fine bubbles are easily formed. It was confirmed by experiments that a group could be generated.

In the case where such chloride ions are used, a desalting section is provided at a stage subsequent to the water treating section of the aqueous solution, and the chloride ion is provided in the desalting section. The aqueous solution from which the ions have been concentrated and discharged is preferably used as an aqueous solution containing chloride ions.

According to this invention, chloride ions can be circulated in the system and reused by reusing them as an aqueous solution containing chloride ions. As the desalting device, a device capable of coagulating the salt concentration by a reverse osmosis membrane method or an electrodialysis method may be used. The purified water after the desalination apparatus is discharged or reused as purified water.

The invention according to claim 11 is that, by applying a high frequency of 10 MHz to 1 GHz together with a bubble group including fine bubbles having a diameter of 10 μm or less to the aqueous solution, the bubble group and the solute substance in the aqueous solution are reduced. It is characterized by improving the adsorbing action.

According to the invention, by applying a high frequency of 10 MHz to 1 GHz to the water treatment section, water molecules (bound water) of hydration existing around the dissolved substance in the aqueous solution are broken, and By exposing the electric dipole to the relaxed melt, the adsorption power with bubbles is increased and the separation efficiency is increased.

The invention according to claims 12 to 16 relates to an apparatus for suitably carrying out the invention, and is described in claim 12.
In the invention described in the above, in a water treatment apparatus for separating or concentrating the solute from an aqueous solution containing a solute such as nitrogen, phosphorus, or an organic water-soluble dissolved substance bound to bound water by an intermolecular force, In the storage tank in which the aqueous solution is stored, the bound water bound to the solute is destroyed or separated, and the solute is added to the solute with means for inhibiting the bound water from re-binding. From the aqueous solution by coagulation or concentration of a dissolved substance containing the solute.

In this case, it is preferable that the means for inhibiting the re-constraint of the confined water is a group of fine bubbles having a diameter of 10 μm or less.
It is also mentioned that a high frequency of 10 MHz to 1 GHz, an ultrasonic wave having a peak value in a plurality of frequency ranges, a chloride ion of 0.1 mol / liter or more, a group of fine bubbles having a diameter of 10 μm or less, or a combination thereof is preferable. Has already been done.

Further, means for generating a bubble group including fine bubbles having a diameter of 10 μm or less include means for generating fine bubbles by cavitation generated by application of ultrasonic waves, and chloride ions of 0.1 mol / liter or more. While supplying the aqueous solution containing
A means for blowing air into the aqueous solution containing the chloride ions through a filter plate to form bubbles in the water treatment unit, and providing an electrode plate in the water treatment unit for the aqueous solution, and providing at least 0.1 mol / liter or more. Means for applying a voltage to the electrode plates to cause electrolysis while forming an aqueous solution containing chloride ions between the electrode plates to form a bubble group; Pressurized water in which air is dissolved in the aqueous solution under pressure is supplied into a water treatment section of the aqueous solution, and any one of means for forming a bubble group by a pressurized levitation method;
Or a combination of a plurality of bubbles, and as described in claim 16, the means for generating a bubble group including fine bubbles having a diameter of 10 μm or less is 0.1.
An aqueous solution containing 1 mol / liter or more of chloride ions is supplied to the lower part of the storage tank, and the chloride ion aqueous solution storage section is provided with physical means for generating air bubbles. It has already been described that a desalination treatment tank is provided in the subsequent stage, and the aqueous solution in which chloride ions are concentrated and discharged in the desalination treatment tank is resupplied to the lower part of the storage tank.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to an embodiment shown in the drawings. However, unless otherwise specified, dimensions, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the invention, but are merely illustrative examples.

An experiment performed to demonstrate the present invention will be described with reference to FIGS. Fig. 1 shows an experimental device that demonstrates that microbubbles are formed using cavitation by ultrasonic waves, and that a dissolved substance can be aggregated together with the bubbles by the sound pressure of ultrasonic waves by forming standing waves. FIG. In the figure, reference numeral 1 denotes a cylindrical glass tube into which an aqueous solution 2 to be tested is injected. The upper end of the glass tube 1 is open, and the lower end is sealed with glass or a rubber film so that the aqueous solution 2 to be tested is not spilled. Is closed. Reference numeral 4 denotes a petri dish-like container which is filled with water 3 for transmitting ultrasonic waves, and the glass tube bottom is immersed in the water 3. Reference numeral 5 denotes an ultrasonic vibrator, which is disposed in contact with the bottom of the container. Reference numeral 6 denotes an ultrasonic oscillation power supply, and reference numeral 7 denotes an ultrasonic sensor provided on the upper side surface of the glass tube 1.

The following experiment was conducted using such an apparatus. Water 3 for transmitting ultrasonic waves is placed in a container 4 having an ultrasonic transducer 5 attached to the bottom, and a glass tube 1 containing an aqueous solution 2 to be tested is placed therein. The inner diameter of the glass tube 1 used in the experiment was 20 mmφ, and the ultrasonic oscillation power source 6 was used.
A sine wave with a frequency of 38 kHz from the
Supplied at an output of 0W. As the aqueous solution 2 to be tested, 10% by weight of sugar water, which is one of the organic compounds, was added and ultrasonic waves were applied. Simultaneously with the application, a portion having a different refractive index was generated in the aqueous solution, and a difference in concentration was visually observed as a difference in refractive index. The separated portion was relatively stable and maintained its shape even when the ultrasonic wave was stopped.

FIG. 2 shows an example of the experimental results. In FIG.
It can be seen that the sugar molecules are concentrated at the nodes of the standing wave formed in the glass tube 1 by the application of the ultrasonic wave (at approximately 4/5 and approximately 2/5 of the height of the aqueous solution). The solution was collected from the portion corresponding to the node of the standing wave and the portion corresponding to the antinode, and the amount of carbon contained in the solution was measured using an organic carbon meter (TOC-500 manufactured by Shimadzu Corporation). The carbon content was increased by about 30% compared to the minute. This result means that the sugar in the solution was concentrated in the nodes.
Immediately after the ultrasonic wave was stopped, very fine bubbles were observed to rise from the nodes. Since such a cohesive separation phenomenon cannot be observed in the degassed aqueous solution,
It can be seen that very fine bubbles were formed by cavitation, and the bubbles were collected and aggregated by the sound pressure of the ultrasonic wave.

FIG. 3 shows a spectrum diagram of the ultrasonic frequency measured by the ultrasonic sensor provided on the side of the glass tube 1 of FIG. The oscillation frequency is 38 kHz, but the oscillation frequency is 3 kHz.
In addition to 8 kHz, 57 kHz which is a harmonic with a small intensity
It can be seen that peak waveform signals of z, 76 kHz and 95 kHz appear. It is presumed that peak waveform signals of 57 kHz, 76 kHz, and 95 kHz appear due to a combination of a standing wave of 38 kHz and a traveling wave generated by reflection resonance of the standing wave. Also, it has been confirmed by a known experiment that the separation phenomenon does not easily occur in the spectrum of only 38 kHz.

From the above experimental facts, when cavitation occurs at a frequency component higher than the frequency at which a standing wave is formed to generate microbubbles containing a large number of bubbles having a diameter of 10 μm or less, the bubbles are dissolved in an aqueous solution. In this experiment, the mass was adsorbed with sugar molecules, so that the mass was a solute substance dissolved in the aqueous solution by agglomerating the nodes with sound pressure that forms a standing wave, and in this experiment, 38 kHz ultrasonic waves. It was also found that aggregation separation was possible.
In this experimental example, sugar water was used, but it has been confirmed that alcohol water such as ethanol or a saline solution has a similar coagulation / separation effect. In addition, it has been confirmed that the same phenomenon occurs at a frequency of 100 kHz as a frequency for forming a standing wave, and there is no limit to the frequency band. Therefore, a frequency range of 20 kHz to 500 kHz which is usually used as an ultrasonic wave is used. It is desirable to do.

FIG. 4 is a schematic diagram of an ultrasonic wastewater treatment apparatus to which the above principle is applied. In the figure, reference numeral 11 denotes a wastewater treatment tank, and reference numeral 12 denotes an aggregation part extraction port provided at the bottom of the treatment tank 11, and an aggregation part extraction port 12 is preferably provided at a position corresponding to a node of a standing wave. Reference numeral 13 denotes a drain port provided at the lower part of the side wall of the processing tank 11, 5 denotes a pair of ultrasonic vibrators provided on both sides of the side wall of the processing tank 11, and 6 denotes an ultrasonic oscillation power supply. A high frequency having a plurality of frequencies as shown in FIG. 3 is generated, amplified and applied to the ultrasonic vibrator 5 by an ultrasonic oscillation power supply.
The ultrasonic transducers 5 may be arranged facing each other as shown in the figure, or may be provided alone. However, the ultrasonic transducers 5 are generated not only by standing waves but also by beats in the processing tank 11. It is good to mix the wave progression.

In such a configuration, the ultrasonic oscillator 5 is vibrated by the ultrasonic oscillation power supply 6 in a state where the raw water to be treated is supplied to the wastewater treatment tank 11 having the ultrasonic oscillator 5 attached to the side and is filled with water. In the wastewater treatment tank 11, fine bubbles and standing waves due to cavitation based on ultrasonic waves, and progressive components generated by beats are formed. As a result, the dissolved substance agglomerated in the standing node is extracted from the aggregating section extraction port 12 and fed to the sludge treatment step.

On the other hand, the aqueous solution from which the dissolved substances have been removed is discharged to the outside of the apparatus through the drain port 13 and the waste water is purified by a downstream purifier. In addition, the purification performance of raw water can be improved by using this apparatus in multiple stages, which leads to a reduction in the burden on the downstream side.

FIG. 5 shows an apparatus diagram for forming bubbles by cavitation by applying ultrasonic waves, concentrating the solution and separating the dissolved matter. (A) is a case where the ultrasonic vibrator 5 is attached to the bottom of the processing tower 23, and (b) is a case where the ultrasonic vibrator 5 is attached to the processing tower 23.
FIG. 3 is a schematic view showing a case where the camera is attached to both side surfaces. In the figure, 24 is a tank, 22 is a reflector, and in the case of (a) in which the ultrasonic oscillator 5 is attached to the bottom of the processing tower 23, the ultrasonic oscillator 5 is disposed downward at the top of the tower to oppose the ultrasonic oscillator 5. In the case of (b) in which the vibrators 5 are attached to both sides of the side of the processing tower 23, the vibrators 5 are vertically arranged vertically in the center of the tower and opposed to the ultrasonic vibrator 5.

In such a configuration, after a part of the processing liquid supplied to the tank is guided to the processing tower 23, the ultrasonic vibrator 5 is installed at the bottom or one side of the processing tower 23,
Vibration is performed using the ultrasonic oscillation power supply 6 to apply ultrasonic waves 21. By applying ultrasonic waves to the aqueous solution, fine bubbles are generated by cavitation in the aqueous solution, and the ultrasonic waves are repeatedly reflected by the reflectors arranged opposite to each other. Further, the pressure sparse portion is amplified, and bubbles are easily generated. The reflection plate 22 is not always an essential requirement as long as a situation where cavitation occurs is created.

Since bubbles generated by cavitation and the like float by adsorbing the dissolved matter, the bubbles and solutes floating on the upper part of the treatment tower 23 are collected in an overflow type storage part and sent to a sludge treatment step. On the other hand, the purified processing liquid is drained from the discharge port 25 at the lower part of the processing tower 23 as drainage, so that drainage can be purified.

Further, the present inventors have noticed that fine bubbles are formed in an aqueous solution having a high ion concentration, particularly when the chloride ion concentration is high. It is a known fact that fine bubbles are formed in seawater as compared to freshwater. Actually, it can be seen that when the salt concentration is increased while bubbling air, fine bubbles are formed and the aqueous solution becomes cloudy. Since the formation of bubbles of 10 μm or less cannot be visually confirmed, the experiment was performed according to the experimental procedure shown in FIGS. 6 (A) and 6 (B).

In the experiment, first, as shown in FIG. 6A, distilled water 32 of which chloride ion concentration was adjusted was placed in a container 31, air was bubbled from an air cylinder 34 with a ball filter 33, and thereafter, As shown in FIG. 6B, the dissolved oxygen concentration of the aqueous solution was measured while flowing a nitrogen gas 36 above the liquid surface, and the deoxygenation process was observed. If very fine bubbles are formed and dissolved by air bubbling, the oxygen removal rate decreases due to the re-dissolution of oxygen from the fine bubbles remaining in the aqueous solution as the concentration of dissolved oxygen decreases. Should be.

More specifically, as shown in FIG. 6 (A), 250 cc of distilled water whose salt concentration was previously adjusted using NaCl as the salt was stirred with a stirrer 35 while stirring.
Kinoshita Ball Filter G4 (Kinoshita Chemical Co., Ltd.)
300cc air from the air cylinder 34 through the
Bubbling at / min. Thereafter, bubbling was stopped, and nitrogen gas 36 was supplied at 300 CC / m as shown in FIG.
The liquid oxygen is supplied to the liquid surface at "in", and the decreasing tendency of the dissolved oxygen concentration over time is measured.

FIG. 6C shows the result of measurement on an aqueous solution having a NaCl concentration of 0 to 1.0 mol / l. As is clear from this graph, the deoxygenation rate from the aqueous solution has been slowed from the time when the NaCl concentration exceeded 0.2 mol / l, and it became clear that the salt concentration became more pronounced. This is because fine bubbles that are invisible are formed in the aqueous solution by air bubbling, and oxygen is redissolved from the bubbles to the aqueous solution side during the deoxygenation process. It depends. Therefore, when an aqueous solution having a chloride ion concentration of 0.2 mol / l or more is used, fine bubbles can be formed.

FIG. 7 shows that the diameter is 10 μm by bubbling.
FIG. 1 is a schematic view of an apparatus for forming the following fine bubbles. A storage section 210 for the chloride ion-containing water 203 is provided in the lower portion of the wastewater treatment tank 101, and the storage section 210 has a capacity of 0.1%.
At least mol / liter of chloride ion-containing water 203 is supplied, and air from the compressor 202 is supplied to the storage unit 2.
By supplying the fine bubbles through a filter plate 201 provided on the bottom face 10, a group of fine bubbles containing many bubbles with a diameter of 10 μm or less is formed.

FIG. 8 is a schematic view of an apparatus for forming a group of fine bubbles having a diameter of 10 μm or less by electrolysis. Chloride ion-containing water 2
03 is provided, a chloride ion-containing water 203 of 0.1 mol / L or more is supplied to the storage unit 210, and a pair of electrodes 205 are arranged in the storage unit 210 to face each other. Alternatively, by applying an AC voltage, electrolysis is caused to form a fine bubble group containing many bubbles having a diameter of 10 μm or less.

FIG. 9 is a schematic view of an apparatus for forming fine bubbles having a diameter of 10 μm or less by a pressurizing method.
Water 203 containing 0.1 mol / L or more of chloride ions is supplied to the pressurized tank 103,
The pressurized water obtained by pressurizing and dissolving the air in 2 is discharged into a wastewater treatment tank 101.
By supplying it to the lower part, a fine bubble group containing a large number of bubbles having a diameter of 10 μm or less is formed.

The air bubbles formed in the wastewater treatment tank 101 in FIGS. 7, 8 and 9 combine with fine solids, microorganisms, organic compounds, solutes and the like dissolved in the treated water and rise. The separation and purification is performed by the
Through to the sludge treatment process.

FIG. 10 is a schematic diagram of an apparatus obtained by adding a desalination apparatus to the apparatus of FIG. The aqueous solution treated by the wastewater treatment device 101 is guided to the desalination device 207, the salt in the aqueous solution is separated by the desalination device 207, the aqueous solution from which the salt has been removed is drained, and the aqueous solution in which the salt is concentrated is converted into a chloride solution. The substance is reused in the system as water 203 containing 0.1 mol / l or more of substance ions. The chloride ion-containing water 203 is pressurized by air from a compressor 202 in a pressurized tank 103 and supplied to the wastewater treatment tank 101 as pressurized water.
Since the pressure of the pressurized water containing chloride ions is released in the wastewater treatment tank 101, a group of fine bubbles containing a large number of bubbles having a diameter of 10 μm or less is formed, and organic substances and solute molecules adsorbed by the fine bubbles are removed. can do.

As the desalting device, a device capable of coagulating the salt concentration by a reverse osmosis membrane method, an electrodialysis method or the like may be used. The purified water after the desalination apparatus is discharged or reused as purified water. The apparatus to which the desalination apparatus of FIG. 10 is added is shown by the pressurization method, but it is needless to say that the same can be applied to the bubbling method of FIG. 7 and the electrolysis method of FIG.
In addition, the salt concentration in the wastewater from the desalination unit 207 that goes out of the apparatus and the salt concentration in the treated water that enters the treatment tank 101 are set to be substantially the same, and 0.1 mol / mol in the desalination unit 207 is used.
By controlling the chloride ion concentration of the chloride ion-containing water 203 of 1 liter or more, the salt concentration can be kept high in the system without supplying salt from the outside except when the apparatus is started up, so that the processing capacity can be kept constant. Can be maintained.

It should be noted that seawater can also be used for the chloride ion-containing water 203 of 0.1 mol / liter or more, and in places where discharge is permitted, seawater is used without providing a desalination device 207. It is also possible. In this case, the device configuration shown in FIGS. 7, 8 and 9 can be directly applied.

Next, water molecules called bound water are adsorbed around the solute substance dissolved in the aqueous solution, and the movement of this bound water is restricted by the solute substance unlike free water. As described above, the present inventors have found that in the case of an organic compound, 10 MHz to 1 GHz
It was found that the high frequency was absorbed by the confined water.

FIG. 12 shows a configuration diagram in the case of using the pressurizing method of FIG. 10 and applying high-frequency application together. In the present embodiment, a pair of high-frequency electrodes 208 are installed facing each other in the wastewater treatment tank 101, and a high-frequency power supply 209 is used to supply a high frequency of 10 MHz to 1 GHz to the wastewater treatment tank 10.
1 Irradiates the solute material inside, destroys the structure of the bound water around the solute material, and reveals the electric dipole of the solute material itself, thereby accelerating the adsorption with bubbles and accelerating the separation efficiency. .

As a simulation experiment based on such an apparatus, an aqueous glucose solution was used as one of the organic compounds. For the measurement, a coaxial probe was put into the sample solution, a high frequency was applied from there, and the absorption of the high frequency applied by the sample solution was measured. The applied frequency is 400 MH
The experiment was performed by changing the incident power from 1 W to 100 W using z. The experimental results show that as shown in FIG. 11, the absorption amount increases as the glucose concentration increases. Also, the reason why the absorption amount decreased with the increase in the incident power is that the bound water around glucose was destroyed. Since the absorption of free water is at about 18 GHz,
The high frequency of 00 MHz is not so much absorbed by the large amount of free water, and can target only the restricted water of the solute substance with small electric power.

[0058]

As described above, according to the present invention, the load of the biological treatment means in the post-process can be reduced, and the bound water can be bound by the intermolecular force without using any flocculant which is environmentally problematic. It is possible to provide a water treatment method and a water treatment method capable of easily coagulating and separating a solute substance contained therein, and in particular, an organic system, a phosphorus system, and a nitrogen system dissolved in an aqueous solution as well as solids, microorganisms, and organic compounds. And a water treatment method capable of positively removing solute substances including the solute substance.

As a result, only wastewater treatment facilities such as sewage treatment facilities, human waste treatment facilities, livestock wastewater treatment facilities, marine processing wastewater treatment facilities, food processing wastewater treatment facilities, washing wastewater treatment facilities, factory wastewater treatment facilities, lake water purification facilities, etc. However, the present invention is also applicable to a process for concentrating and purifying dissolved substances from an aqueous solution. When the present invention is applied to a wastewater treatment facility, not only can a wastewater purification method be replaced by an apparatus such as an activated sludge method, but also the apparatus is compact and the amount of solid waste of residual activated sludge is reduced, and in the case of excreta treatment, etc. It can be reused for fertilizers.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an experimental apparatus illustrating the principle of the present invention.

FIG. 2 is a schematic diagram showing the state of concentration and separation of the aqueous sugar solution performed in FIG.

FIG. 3 is a frequency spectrum diagram of an ultrasonic sensor output attached to the experimental apparatus of FIG.

FIG. 4 is a schematic diagram of an ultrasonic wastewater treatment apparatus according to the first embodiment of the present invention.

FIG. 5 is a schematic diagram of an ultrasonic wastewater treatment apparatus according to a second embodiment of the present invention.

FIG. 6 is a schematic diagram of a degassing test based on a difference in salt concentration.
(A) and (B) are experimental devices, and FIG. 6 (C) is a graph showing the experimental results.

FIG. 7 is a schematic diagram of a wastewater treatment apparatus using a bubbling method according to a second embodiment of the present invention.

FIG. 8 is a schematic diagram of a wastewater treatment apparatus using an electrolysis method according to a second embodiment of the present invention.

FIG. 9 is a schematic view of a wastewater treatment apparatus using pressurized water according to a second embodiment of the present invention.

FIG. 10 is a schematic diagram of a wastewater treatment apparatus using pressurized water to which a desalination apparatus according to a second embodiment of the present invention is added.

FIG. 11 is a graph showing the results of a high-frequency absorption test for glucose and distilled water.

FIG. 12 is a schematic diagram of a pressurized water wastewater treatment apparatus according to a second embodiment of the present invention.

FIG. 13 is a schematic diagram of a wastewater treatment apparatus according to the related art, which employs a pressurized flotation method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass tube 2 Experimental aqueous solution 3 Water for ultrasonic transmission 4 Container 5 Ultrasonic vibrator 6 Ultrasonic oscillation power supply 7 Ultrasonic sensor 11 Drainage treatment device 12 Aggregation part extraction port 21 Ultrasonic traveling direction 22 Reflection plate 23 Processing Tower 24 Tank 101 Wastewater treatment tank 102 Activated sludge treatment tank 103 Pressurized tank 201 Filter plate 202 Compressor 203 Chloride ion-containing water 205 Electrolysis electrode 206 Power supply 207 Desalination device 208 High-frequency electrode 209 High-frequency power supply

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoshi Tatsuhara 1-8-1 Koura, Kanazawa-ku, Yokohama-shi Mitsubishi Heavy Industries, Ltd. Basic Technology Research Laboratory (72) Inventor Kiyoshi Sugata 1-8-8 Koura, Kanazawa-ku, Yokohama-shi 1 Mitsubishi Heavy Industries, Ltd. Yokohama Research Laboratory (72) Inventor Ichiro Yamashita 1-8-1, Koura, Kanazawa-ku, Yokohama-shi F-term, Mitsubishi Heavy Industries, Ltd. Yokohama Research Laboratory 4D037 AA05 AA11 AB02 AB03 AB11 AB12 AB15 BA02 BA03 BA26 BB04 BB05 BB09 CA04 CA07 CA08

Claims (16)

[Claims] 1. A water treatment method for separating a solute from an aqueous solution containing a solute bound to bound water by an intermolecular force, wherein the bound water bound to the solute is destroyed or separated; A water treatment method, wherein the solute is aggregated and separated from an aqueous solution while providing the solute with a means for inhibiting re-constraint of bound water. 2. A water treatment method for coagulating and separating nitrogen, phosphorus or an organic water-soluble solution from an aqueous solution, wherein the water-soluble solution is destroyed or separated from bound water bound to the water-soluble solution by an intermolecular force. A water treatment method, wherein the dissolved substance is aggregated and separated from the aqueous solution while providing a means for inhibiting re-restraint of the bound water in the aqueous solution. 3. A water treatment method for concentrating a dissolved substance from an aqueous solution, the method comprising destroying or separating bound water bound to a water-soluble dissolved substance by an intermolecular force and inhibiting rebinding of the bound water. A water treatment method, wherein the dissolving substance is concentrated while applying means to the aqueous solution. 4. The means for inhibiting re-constraint of the confined water,
4. The water treatment method according to claim 1, wherein the group of microbubbles has a diameter of 10 μm or less. 5. The means for destroying or separating the confined water includes high-frequency waves of 10 MHz to 1 GHz, ultrasonic waves having peak values in a plurality of frequency ranges or chloride ions of 0.1 mol / liter or more, and a diameter of 10 μm or less. 4. The water treatment method according to claim 1, wherein the water treatment method is a group of fine bubbles or a combination thereof. 6. The water treatment method according to claim 4, wherein, as means for generating a bubble group containing fine bubbles having a diameter of 10 μm or less, fine bubbles are generated by cavitation generated by applying ultrasonic waves. 7. As a means for generating a bubble group containing fine bubbles having a diameter of 10 μm or less, an aqueous solution containing 0.1 mol / liter or more of chloride ions is supplied into a water treatment section of the aqueous solution. 5. The water treatment method according to claim 4, wherein air is blown into said aqueous solution containing chloride ions through a filter plate to form bubbles in said water treatment section. 8. An aqueous solution containing 0.1 mol / liter or more of chloride ions, wherein an electrode plate is provided in a water treatment part of the aqueous solution as means for generating a bubble group containing fine bubbles having a diameter of 10 μm or less. While supplying between the electrode plates,
The water treatment method according to claim 4, wherein a voltage is applied to the electrode plate to cause electrolysis to form a bubble group. 9. As means for generating a bubble group containing fine bubbles having a diameter of 10 μm or less, pressurized water obtained by pressurizing and dissolving air in an aqueous solution containing 0.1 mol / L or more of chloride ions is used. An aqueous solution is supplied into a water treatment section, and bubbles are formed by a pressure flotation method.
Water treatment method as described. 10. A desalination treatment section is provided at a stage subsequent to the water treatment section for the aqueous solution, and an aqueous solution in which chloride ions are concentrated and discharged in the desalination treatment section is used as an aqueous solution containing chloride ions. 10. The water treatment method according to claim 7, 8.9. 11. An aqueous solution containing a group of fine bubbles having a diameter of 10 μm or less, together with a group of bubbles of 10 MHz to 1 MHz.
The water treatment method according to any one of claims 1 to 3, wherein a high frequency of GHz is applied to improve a function of adsorbing bubbles and a solute substance in an aqueous solution. 12. A water treatment apparatus for separating or concentrating a solute from an aqueous solution containing a solute such as nitrogen, phosphorus, or an organic water-soluble dissolved substance bound to bound water by an intermolecular force. In the storage tank in which the aqueous solution is stored, the bound water bound to the solute is destroyed or separated, and the solute is added to the solute with means for inhibiting the bound water from re-binding. A water treatment apparatus, wherein coagulation is separated from an aqueous solution or a solution containing the solute is concentrated. 13. The water treatment apparatus according to claim 12, wherein the means for inhibiting the re-constraint of the confined water is a group of fine bubbles having a diameter of 10 μm or less. 14. The means for destroying or separating the confined water includes a high frequency of 10 MHz to 1 GHz, an ultrasonic wave having a peak value in a plurality of frequency ranges or a chloride ion of 0.1 mol / liter or more, and a diameter of 10 μm or less. The water treatment apparatus according to claim 12, wherein the water treatment apparatus is a group of fine bubbles or a combination thereof. 15. A means for generating a bubble group including fine bubbles having a diameter of 10 μm or less, comprising: means for generating fine bubbles by cavitation generated by application of ultrasonic waves;
While supplying an aqueous solution containing 0.1 mol / L or more of chloride ions into the water treatment section of the aqueous solution, air is blown into the aqueous solution containing the chloride ions through a filter plate, and the air is blown into the water treatment section. Means for forming a group of bubbles in an electrode plate, an electrode plate is provided in a water treatment part of the aqueous solution, and an aqueous solution containing 0.1 mol / l or more of chloride ions is supplied between the electrode plates while a voltage is applied to the electrode plate. Is applied to cause electrolysis to form bubbles, and pressurized water obtained by pressurizing and dissolving air in an aqueous solution containing 0.1 mol / L or more of chloride ions is supplied to the water treatment section of the aqueous solution. The water treatment apparatus according to claim 13, wherein the water treatment apparatus is any one or a combination of a plurality of means for forming a bubble group by a pressure flotation method. 16. A means for generating a bubble group containing fine bubbles having a diameter of 10 μm or less supplies an aqueous solution containing 0.1 mol / liter or more of chloride ions to a lower portion of the storage tank, and An aqueous solution in which chloride ions are concentrated and discharged in the desalting treatment tank is provided while providing a physical means for generating bubbles in the storage section of the target ion aqueous solution, and providing a desalting treatment tank at a stage subsequent to the storage tank. The water treatment apparatus according to claim 13, wherein the water is resupplied to a lower portion of the storage tank.