JPH0148831B2 - - Google Patents

Description

[Detailed description of the invention] (a) Purpose of the invention [Field of industrial application] This invention relates to a liquid purification device using sound waves, and is used to improve the pollution of drinking water and industrial water, and to improve the quality of other liquids. Used for improvement.

[Conventional technology] Looking at the current state of water pollution in Japan, there has been considerable improvement in harmful substances such as cadmium, cyanide, and alkyl mercury as a result of stricter wastewater regulations. The current situation is that rivers, lakes, and other areas related to conservation have become quite serious problems. In other words, this is a water quality indicator of organic pollution in rivers and lakes.
Looking at the achievement rate for environmental standards regarding BOD and COD, the level remains low at 65.3% for rivers and 41.7% for lakes. The reality is that the ocean remains at a low level in closed water areas with major sources of pollution, such as Tokyo Bay and Ise Bay. In addition, since tap water is provided for human consumption, it is not only safe but also unsuitable for drinking if it has an abnormal odor.
The raw water used to make tap water needs to be as clean as possible, but the rivers and lakes from which it is sourced have become contaminated, making it difficult to obtain high-quality raw water. In particular, in recent years, eutrophication in natural lakes and reservoirs has resulted in abnormal growth of algae, which has caused damage to water that tastes and smells strange.
In addition, industrial water is generally treated by chemical precipitation, but this only removes colloidal pollutants, and it is difficult to sufficiently remove dissolved inorganic and organic substances. In addition, regarding damage to fisheries due to marine pollution, oil pollution,
Damages such as the death, poor growth, or inability of aquatic organisms to grow due to occurrences of red tide, etc. are occurring. To overcome these problems, new and effective technologies for water purification are needed.

Conventionally, techniques for removing pollutants from water and liquids to improve water and liquid quality include:
There are chemical methods such as chemical precipitation as described above, and physical methods such as filtration.

[Problems to be Solved by the Invention] However, these chemical and physical methods require large-sized equipment, short replacement cycles, and are expensive.

This invention was made in view of the above-mentioned circumstances, and it is possible to easily and reliably remove pollutants in water or liquids with a simple device without the need for chemicals, and to prevent clogging. It is an object of the present invention to provide a liquid purification device that does not require conversion of parts due to the above.

(B) Structure of the Invention [Means for Solving the Problem] Corresponding to this object, the liquid purification device using sound waves of the present invention includes a vibrator capable of emitting sound waves into a container containing a liquid to be treated, and the above-mentioned vibrator. Reflection plates capable of reflecting sound waves are arranged oppositely and at variable relative intervals, and an extraction device capable of extracting the liquid to be treated at an arbitrary position between the vibrator and the reflection plate is provided. It is a feature.

Hereinafter, details of the present invention will be explained with reference to the drawings showing one embodiment.

In FIG. 1, reference numeral 1 denotes a purification device, and the purification device 1 has a pipe-shaped closed container 3 having a cylindrical or rectangular cross section that can contain a liquid to be treated 2 at one end.
A piston-shaped reflecting plate 4 is attached to the other end, and a vibrator 5 made of piezoelectric ceramic or the like is attached to the other end. The vibrator 5 serves as a sound wave radiator and can radiate sound waves into the inside of the sealed container 3. The piston-shaped reflector 4 has a structure in which the distance L between the reflector 4 and the vibrator 5 can be changed, and the airtight container 3
Adjust so that the sound waves radiated into the space create standing waves. That is, the distance L between the reflector 4 and the vibrator 5
to generate a standing wave. The conditions for this are shown below. That is, when the wavelength of the radiated sound wave is λ, L is set to the following value.

L = (2m + 1) * (λ/4) ... (1) m = 0, 1, 2, 3, ... However, here, we will explain the correction terms, etc. in order to explain in more detail using equation (1). has been omitted.

Figure 2 shows the reflector 4 and the vibrator 5 based on equation (1).
This figure shows the results of calculating the value of the distance L between the two for pure water and air. In FIG. 2, the line marked C=1430 m/s is for pure water, and the line marked C=331 m/s is for air. In either case,
Three cases of m=0, 1, and 2 are shown. According to FIG. 2, how should we set the distance L between the reflection plate 4 and the vibrator 5 in relation to the frequency of the sound wave generated by the vibrator 5? It becomes clear whether this will occur.

A pipe 7 is erected at the center of the upper surface of the reflecting plate 4, and the pipe 7 projects onto a frame plate 8 supporting the closed container 3. A rack 11 is formed on the outer surface of the upper end of the pipe 7.
1 is meshed with pinion 12. Frame board 8
When the motor 13 supported by the motor 13 is driven, its rotation is transmitted to the rack 11 via the pinion 12, and the reflector 4 moves up and down, thereby adjusting the distance L.

A plurality of small holes 6 are made in the wall of the closed container 3. The liquid 2 to be treated, such as water to be purified, passes through this hole 6 and enters the inside of the closed container 3, so that the inside of the closed container 3 is always filled with liquid.

Furthermore, an extraction device 14 for extracting the liquid to be treated is disposed within the closed container 3. Extraction device 14
comprises a block 15 supported on a frame 21. The block 15 is driven by a motor 16 and a pulley 17 directly connected to the motor 16, and can smoothly move along a guide rail 18.

Frame 2 fixed to support pipe 22
1 rotates at the same angle as the stay 23 due to splines etched on the outer surface of the support pipe 22, but can slide vertically in a sliding state. A gear 24 is attached to the stay 23, and a gear 26 is attached to the motor 25.
By the rotation of the motor 25,
The frame 21 can be rotated to any angle. Further, a motor 29 is attached to the stay 23, and a pinion 30 is attached to the shaft of the motor 29. The pinion 30 is fitted into a rack 35 provided on the support pipe 22, and drives the support pipe 22 up and down.

A suction port 27 for suctioning the liquid to be treated is attached to the block 15 and is open. The suction port 27 is connected to a pipe 28 to transport liquid with high contamination concentration from the closed container 3 to the outside. This pipe 28 is highly flexible, and the position of the suction port 27 can be moved to any position inside the closed container 3, as will be described later. The pipe 28 passes through the support pipe 22 and is connected to the pump 31.
This pump 31 is used to suction pollutants.

Near the suction port 27, as shown in FIG. 4, a light emitting fiber 32 and a light receiving fiber 33 are located facing each other. A light emitting fiber 32 and a light receiving fiber 33 are located facing each other. The light emitting fiber 32 and the light receiving fiber 33 are connected to the outside of the closed container 3 by an optical fiber 34 through the support pipe 22, making it possible to perform measurements using optical applications.

That is, in order to measure the concentration of pollutants, the fluid filling the airtight container 3 from the light emitting fiber 32 (in the present invention, it is not limited to liquid, but can be considered to include gas and mixed fluid). The light is emitted into the light-receiving fiber 33 and received by the light-receiving fiber 33.

As the light to be irradiated, semiconductor laser light, argon laser light, etc. are used, but depending on the case, light from a light emitting diode, xenon lamp light, etc. may be used. For light reception by the light receiving fiber 33, a light receiving element, a photodiode, etc. are used.

Depending on the type of pollutant, it may absorb the irradiated light and emit part of the absorbed light as light with a wavelength different from that of the incident light, which may be fluorescence. In such cases, methods such as analyzing fluorescence spectra may be considered. However, it may be sufficient to simply measure the amount of light attenuation to determine the difference in contaminant concentration depending on location. Further, a circuit configuration for removing disturbance light such as sunlight may also be considered. In any case, in the present invention,
In order to achieve the highly efficient removal of contaminants, which is the objective of the present invention, it is natural that a systematic configuration will be desired as a means of automated measurement in a better manner will be taken.

The material of the optical fiber 34 for transmitting optical signals may be quartz, multi-component glass, plastic, polycrystalline, or the like.

Note that since FIG. 1 shows an example, the meters 38, pump 31, etc. are arranged near the closed container 3, but of course they may be arranged at remote locations.

Alternatively, a water suction pipe network consisting of a large number of suction ports may be installed to efficiently collect only liquid with a high concentration of contamination.

[Function] The function of the purifying device 1 configured as described above is as follows.

In a sound field that generates standing waves, the sound pressure distribution or particle velocity is such that the traveling wave and the reflected wave interfere with each other, so the antinode of the overlapping part with the same phase and the node of the overlapping part with the opposite phase , the state is alternately distributed.

By the way, force is applied to pollutants floating in a sound field using a liquid as a medium due to the radiation pressure of sound waves. That is, the relationship between the sound pressure radiated from the vibrator 5 and the radiation pressure in the medium is expressed mathematically as follows, where Pr is the radiation pressure per unit area.

Pr='n+ρ()...(2) Here, V is the particle velocity, ρ is the density of the medium, n is the normal vector to the surface of the pollutant, and ' is the time-average value of the sound pressure P, taking into account quadratic effects. It is.

When the acoustic medium has an infinite extent, the average value P' of the sound pressure P, taking into account the second-order effects, is P'=P ² /-/2ρC ² -ρv ² /-/2...(3) It is expressed as However, in the case of a plane wave, the relationship P=ρCv holds between the sound pressure P and the particle velocity V.

Now, when the normal vector n is 1, the results calculated using the above equations (2) and (3) are shown in FIG. 3. In FIG. 3, the sound pressure (N/m ² ) P shown on the horizontal axis is the sound pressure of the sound wave radiated from the vibrator 5 into the sealed container 3, and the radiation pressure (N/m ² ) shown on the vertical axis Pr is the pressure acting on the medium inside the closed container 3. Pollutants suspended in the sound field are subjected to radiation pressure. In Figure 3, ρ
The line shown as = 1.21Kg/m ³ and C = 343m/s is for air, and the line marked as "perfectly reflecting surface" is the pressure at the antinode of the standing wave, and the line marked as "perfectly absorbing surface" is the pressure at the antinode of the standing wave. A line is the pressure at a node in a standing wave. The line written ρ=1000Kg/m ³ and C=1430m/s is for water.

From this equation, it can be seen that the force per unit area Pr acting on the pollutant is considerably smaller than the sound pressure of the sound wave radiated from the vibrator 5 into the sealed container 3. If a sound wave is emitted from the vibrator 5 into the inside of the air, there is no doubt that a force will act on the pollutant. Therefore, in general, a force from the antinode of the sound pressure toward the node acts on the contaminant, which is smaller than the wavelength, and the contaminant eventually moves to the node. As a result, a large amount of pollutants will remain at the nodes. The reason why I say "generally" is that for some pollutants, it is conceivable that movement occurs not from the antinode of the sound pressure toward the node, but conversely from the node of the sound pressure toward the antinode. . If we consider the conditions that govern this, we can say the following.

The pollutants vibrate in the sound field in the direction of sound wave propagation as a result of the radiation pressure. It goes without saying that the radiation pressure acting on a pollutant is proportional to the energy density of the sound wave, but it also depends on the size of the pollutant (here, the size of the target pollutant is naturally much smaller than the wavelength of the sound). ), the density of the medium, the density of the contaminant, the compressibility of the contaminant,
Wave number k of sound wave (k=2π/λ, where λ: wavelength),
This is because it cannot be definitively determined that pollutants move to the node position and remain there.

It is thought that when the specific gravity of the pollutant is relatively heavy, the sound pressure receives a force from the nodes toward the antinode, and when the specific gravity of the pollutant is relatively light, the sound pressure receives a force from the antinode toward the node. In any case, there is no doubt that sound waves cause pollutants to move and stay in specific locations.

As mentioned above, it is clear that sound waves cause pollutants to move to specific places and stay there, but as is clear from Figure 2, it is not simple to accurately determine where they stop. . As mentioned above, it is natural that the radiation pressure acting on a pollutant is proportional to the energy density of the sound wave, but the size of the pollutant (here, the size of the target pollutant is naturally proportional to the sound wave energy density). density of the medium, density of the contaminant, compressibility of the contaminant, wave number k of the sound wave (k
= 2π/λ, where λ is the wavelength), etc., and it cannot be absolutely determined that the pollutants move to the node position and stay there. Therefore, in the present invention, in order to dramatically improve the collection efficiency of pollutants, the following method is adopted.

That is, as shown in FIG. 4 described above, the suction port 27, the light emitting fiber 32, and the light receiving fiber 33 are close to each other, and these remain as one body, preventing pollutants from staying anywhere in the closed container 3. While accurately tracking the location, it smoothly moves and collects polluted substances by applying automatic control techniques.

Therefore, the suction port 27, the light emitting fiber 32, and the light receiving fiber 33 are moved to any location in the closed container 3 according to the command issued based on the CPU of the computer shown in FIG. The explanation of FIG. 5 is as follows. The four motors shown in Figure 1, namely 13, 16, 25,
29 each has an internal sensor using a rotary encoder or a tachometer, and a Claude system consisting of a microprocessor and controller ensures the rotation angle as instructed. In addition to this, information from external sensors is input to the CPU and combined with the above system,
The suction port 27, the light emitting fiber 32, and the light receiving fiber 33 move to an arbitrary position in the closed container 3 as instructed and stop there. Then, it enters the state of waiting for the next command from the CPU, and by the next command,
It moves to any location in the closed container 3 as instructed and stops.

A non-contact type position sensor array 36 is attached to the wall surface of the closed container 3, and has a function as an external sensor, and transmits a signal indicating the position to the CPU.

The instructions from the CPU are as follows.

(1) The distance L between the reflector 4 and the vibrator 5 is changed, and the reflector 4 is moved so as to generate a standing wave.
The value of the interval L uses the value stored in the register of the CPU or the floppy disk. Furthermore, since a microcomputer is used as the CPU, calculations may be performed immediately and a command for the interval L may be output based on the calculation results. (2) Move the suction port 27, the light emitting fiber 32, and the light receiving fiber 33 according to a predetermined program. (3) The CPU outputs a command to measure the concentration of pollutants at each position of the suction port 27, the light emitting fiber 32, and the light receiving fiber 33. (4) When the computer confirms that the concentration of the pollutant exceeds a specified value, the suction port 27 opens or the pump 31 starts to start, and the pollutant is sucked out. (5) If the concentration of pollutants is below the specified level, suction of pollutants is not performed, and movement to the next position is started based on instructions from the CPU. (6)
Programming to track the location with the highest concentration of pollutants can be easily set up in software, so based on that software, the system can be operated with the highest pollutant collection efficiency.

Further, a sensor 37 for detecting the pollution concentration is provided in the middle of the pipe 28, and the pollution concentration is displayed on the meters 38 that display the pollution concentration, and when the concentration exceeds the set value, the relay 41 is activated to turn off the pump 31. It is also possible to start and stop the operation.

There is a filter 42 between the sensor 37 that detects the pollution concentration and the pump 31.
2, the pollutants are filtered out. Filter 42 may be of the cyclone type.

The airtight container 3 is attached to a frame plate 8, as shown in FIG. It can also be set floating near the surface of the water. Figure 1 shows an example of this.
Although the frame plate 8 is shown vertically, it may be possible to attach the frame plate 8 to the side of the closed container 3 and set the closed container 3 parallel to the water surface.

In the above explanation, the case of one is described, but of course the number is not limited to one, and it is more practical to arrange a large number of them in order to improve the efficiency of pollution treatment. In addition, in this processing method, it is possible to remove the sensor 37 that detects the pollution concentration, the meters 38 that display the pollution concentration, the relay 41, etc., and create a simplified system that is operated by a human. These methods are common in that they use sound waves to separate the contaminant concentration into areas with high and low concentrations, and then actively suck and filter only the areas with high contamination concentration, and are therefore included in the scope of this method. It is something that will be done.

(c) Effects of the invention According to this invention, water pollution, etc. can be purified extremely effectively. That is, the present invention uses sound waves to separate liquid, etc. into areas with a high concentration of contaminants and areas with a low concentration of contaminants, and filters only the concentrated areas, so that the purification efficiency of contaminants is extremely excellent. Therefore, it is extremely effective in cleaning water pollution caused by abnormal growth of algae due to eutrophication in lakes and reservoirs. Furthermore, the present invention is excellent in the following points in the purification of industrial water, etc. That is, industrial water is generally treated by chemical precipitation, but this only removes colloidal pollutants, and it is difficult to completely remove dissolved inorganic and organic substances. However, according to the present invention, dissolved inorganic and organic substances can be completely removed. Therefore, the present invention is extremely useful for purifying industrial water and the like. Furthermore, the present invention automatically measures the contaminant concentration using a laser beam or the like, automatically tracks the position of the maximum contaminant concentration under computer control, and only removes liquid with high contamination concentration according to instructions from the computer. Therefore, it can be efficiently collected and purified.

As described above, according to the present invention, pollutants in water or liquid can be easily and reliably removed with a simple device without the need for chemicals, and there is no need to replace parts due to clogging, etc. It is possible to obtain a liquid purification device without having to do so.

[Brief explanation of drawings]

Fig. 1 is an explanatory longitudinal cross-sectional configuration diagram showing a purifying device according to an embodiment of the present invention, Fig. 2 is a graph showing the relationship between the frequency of sound waves and the distance L between the vibrator and the reflector, and Fig. 3 is a graph showing the relationship between the sound wave frequency and the distance L between the vibrator and the reflector. A graph showing the relationship between pressure and radiation pressure,
FIG. 4 is a perspective explanatory view showing the extraction device, and FIG. 5 is a block diagram showing a control device for controlling the operation of the purification device. DESCRIPTION OF SYMBOLS 1...Extraction device, 2...Liquid to be processed, 3...Airtight container, 4...Reflector, 5...Vibrator, 6...
Hole, 7...Pipe, 8...Frame plate, 11...
Rack, 12...Pinion, 13...Motor, 1
4...Extraction device, 15...Block, 16...Motor, 17...Pulley, 18...Guide rail,
21... Frame, 22... Support pipe, 23
... Stay, 24 ... Gear, 25 ... Motor, 2
6...Gear, 27...Suction port, 28...Pipe,
29... Motor, 30... Pinion, 31... Pump, 32... Light emitting fiber, 33... Light receiving fiber, 34... Optical fiber, 35...
Rack, 36...Sensor row, 37...Sensor, 3
8...meters, 41...relay, 42...filter.

Claims (1)

[Claims] 1 A vibrator capable of emitting sound waves and a reflection plate capable of reflecting the sound waves are disposed facing each other at variable relative intervals in a container containing a liquid to be treated, and between the vibrator and the reflection plate. A liquid purification device using sound waves, comprising an extraction device capable of extracting the liquid to be treated at an arbitrary position.