JP3494587B2 - Liquid quality reformer - Google Patents

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid property reforming apparatus which utilizes cavitation to deaerate, mix, stir, sterilize, kill insects, decompose, emulsify liquids and the like. More specifically, liquid is ejected to cause cavitation positively and destruction of biological cells due to the action of the cavitation erosion,
Improve the quality of liquid such as degassing of dissolved gas such as harmful chlorine gas in liquid, mixing / stirring of substances into liquid, sterilization of bacteria in liquid, insecticide of parasites, decomposition of organic matter, emulsification of oil, etc. The present invention relates to a liquid reforming device for improving quality.

[0002]

2. Description of the Related Art A technique for separating and destroying gas and germs in a liquid to reduce the unique effects of the gas and germs, for example, water-bloom in lake water, cells of Legionella spp. In drinking water and bath water. Effective techniques such as elimination of activity and removal of chlorine dissolved in tap water are required. In addition to these soils, Legionella spp. In the natural environment inhabiting freshwater such as ponds, swamps, lakes, rivers, cooling tower water for air conditioning, accumulated water, cutting oil, water in water heaters for domestic and commercial use , Park fountains, water in ultrasonic / distillation humidifiers, circulating whirlpool baths (commonly known as 24-hour baths), dental spray water, and artificial environments that multiply in various types of water in hospitals There is a particular demand for nullification of the physiological and cell activities of Legionella spp.

As of 1996, more than 40 species of such Legionella spp. Are (0.3-0.7).
(2-5) Micron Gram-negative bacteria, which are aerobic and therefore easily proliferate in water that comes into contact with the atmosphere and adversely affect the human body, but also proliferate in ultrapure water for semiconductor manufacturing. Yielding poor semiconductor manufacturing yields. The culture time of Legionella spp. Is extremely longer than that of Escherichia coli, and it is easy to take time to confirm its existence and delay effective countermeasures. Facultative intracellular growth bacteria that coexists with green algae and uses extracellular metabolites as carbon and energy sources, and grows in cells of protozoa such as macrophages in living organisms and amoeba living in the same environment. There is a particular demand for effective extermination of Legionella spp.

On the other hand, it has been proposed to use jet cavitation to destroy water-bloom and the like. With the impact when hitting the jet stream on the impact plate,
A harmful phytoplankton nullification device called freshwater red tide has also been put into practical use, but in general, techniques for nullifying bioactivity have just begun. The physical activity of cavitation has long been known, as shown in a series of physical and technical idioms called cavitation erosion.

[0005] Seawater or water such as squid and fish farming equipment,
It contains gases mainly composed of various components in the air. It contains various components such as oxygen, nitrogen, and carbon dioxide in the air that is a gas at room temperature. Furthermore, the harmful ammonia emitted by fish is changed by the action of microorganisms such as nitrite (HN
It is known to be a component such as O ₂ ), nitrite and nitrate. Further, deep sea water is rich in inorganic nutrients, phosphates and silicates necessary for plant growth. In the case of fresh water such as tap water, it also contains chlorine for disinfection.

Since these substances are generally harmful to the organisms in the water, it is desirable to remove them as much as possible or to change to stable salts which do not affect the organisms. However, it is practically impossible to stabilize or selectively adsorb these harmful substances by neutralizing them with a chemical or the like with a fish farming apparatus having a limited capacity.

That is, even if a trace amount of chemicals for removal remains, the chemicals are concentrated in the living organisms and leave an adverse effect. Due to these problems, land-based aquaculture equipment is abandoned in a short period of time without pumping a large amount of seawater for recycling. For this reason, it is a cause of polluting the seawater near the sea with the consumption of energy.

Cavitation also has the ability to destroy objects, as is known from eroding the metal surfaces of turbine blades. Although the destructive effect of such cavitation is disliked, the technology to utilize it is known only exceptionally,
Not common. Therefore, the research is also delayed. Also, cavitation and eddy currents of high-speed jet fluids are analyzed by the dynamics of complex systems, and are undeveloped academically.Therefore, theoretical results have already been confirmed while incorporating the results of trial and error research. It is preferable to advance engineering and practical development together with the research results that have been obtained.

Techniques based on such research exist in advance. The prior art disclosed in Japanese Patent Application No. 10-316020 related to the same inventor makes air introduction an important technical matter. However, the active introduction of such air
Subsequent verification experiments have revealed that it is rather inappropriate for the purpose of cell destruction and gas-liquid separation. Note that in this specification, cavitation, cavitation bubbles, and cavitation bubbles are used synonymously. Also, cavitation flow and vortex flow are used interchangeably. Furthermore, erosion and erosion are also used synonymously.

[0010]

The present invention has been made based on such a technical background, and achieves the following objects. It is an object of the present invention to provide a liquid quality reforming device that actively utilizes cavitation bubbles to efficiently destroy cells or nullify cell activity. Another object of the present invention is to provide a liquid-quality reforming device that positively utilizes cavitation bubbles to efficiently separate gas dissolved in the liquid.

Still another object of the present invention is to provide a liquid quality reforming apparatus that more effectively achieves the above object by forming a vortex flow of cavitation bubbles. Still another object of the present invention is to provide a liquid quality reforming device that more effectively achieves the above object by moving the vortex flow of cavitation bubbles. Still another object of the present invention is to provide a liquid quality reforming apparatus for efficiently degassing unnecessary gas in a liquid by mixing gas such as air into the liquid after cavitation. .

Still another object of the present invention is to clarify theoretical / experimental mathematical conditions for enhancing the cavitation effect to facilitate the use of the technique, effectively nullify cell activity, remove impurities, It is an object of the present invention to provide a liquid quality reforming device for degassing gas in liquid. Still another object of the present invention is to
Hereinafter, it should be more specifically disclosed through the embodiments.

[0013]

INDUSTRIAL APPLICABILITY The liquid quality reforming apparatus according to the present invention can effectively perform deaeration, mixing, stirring, sterilization, insecticidal, decomposition, emulsification, etc. by cavitation and its vortex flow. Further, the present invention can be formed only by a container and a cavitation nozzle that form a simple closed space, and the cost is extremely low.

The movement of the central region is a geometric movement, but not a physical movement. The water molecules that form the vortex are
Although it has a violent spiral motion, the motion of the central region and the motion of water molecules are virtually unrelated. Such movement in the central area is similar to the movement of a typhoon. In the present invention, the movement in these closed spaces is also referred to as a turbulent flow generating section or a turbulent flow generating means.

The motion of the center of the vortex flow of the cavitation bubble is described by a complicated equation of motion whose boundary condition is the inner surface of a closed space such as a box or a cylinder. Is forming. A myriad of minute bubbles have a boundary surface such as a pressure
The stress gradient is extremely large and it changes rapidly with time. A cell that comes into contact with a liquid having a pressure / stress gradient that exhibits such a temporal change instantaneously loses its cell activity. The pressure gradient also promotes vaporization of the gas in the liquid, thus generating gas-liquid separation, while generating new foaming seeds.

The vortex flow as a whole proceeds from the inlet provided to the container such as the box main body or the cylinder toward the outlet, but the vortex is formed in the course of such progress. This vortex flow is macroscopic in that one is generated at one outlet in principle. Microscopically, innumerable eddies are observed at the beginning of eddy generation,
The sum of the angular momentums of all water molecules appears as one angular momentum. The central region of such an eddy current is also quadratically dynamic, and in a closed system or boundary condition as described above,
Perform a periodic closed movement.

The initial conditions such as the jet velocity of the jet flow causing the vortex motion, the nozzle shape for properly distributing the jet nuclei, and the above-mentioned boundary conditions simultaneously cause shear stress on the vortex flow and cause cavitation. It is also a condition. That is, it can be said that the generation of the vortex of bubbles regulates the generation of cavitation suitable for cell destruction.

It is more effective to generate cavitation if the nozzle is formed as a single nozzle so that only water or a liquid such as seawater is introduced to generate cavitation and air is not positively introduced. ,
Excellent for cell destruction, gas degassing, mixing, etc. However, depending on the purpose, the nozzle may be
Alternatively, it may be formed as a double nozzle having a first nozzle for introducing a liquid such as seawater and a second nozzle for introducing a gas such as air or a liquid.

In this case, in order to give priority to the occurrence of cavitation, in order to make the second nozzle lose its function, it is plugged or a valve capable of controlling the flow rate and completely shutting off is used. Good. By making the plug removable, the box, cylinder, etc. can be used for other purposes. The discharge pressure of the supply to the nozzle is selected and selected from the range of ² kg / mm ² or more depending on the application and effect. Desirably, the degassing of chlorine in tap water is 2 Kg / mm ² or less, and stirring /
Mixing, separation, and sterilization may be 10 kg / mm ² or less, deaeration and sterilization may be 30 kg / mm ² or less, and decomposition of organic substances such as trichlorethylene and dioxin is preferably 100 kg / mm ² or more.

Desirably as a boundary condition of the turbulent flow generation section,
The inner space is flat. Being flat means
It is a condition that does not rotate a vortex with a certain angular momentum in three dimensions (the angular momentum that is a vector has the direction of the central axis of rotation that is orthogonal to the plane), and this condition stabilizes the vortex flow.
In order to make the vortex flow smoothly move, it is effective to provide a curved surface in the space of the turbulent flow generation portion in the direction of motion. Such a vortex has a strong shear stress and promotes the collapse of bubbles, which causes shock waves in the liquid.

If the approximate height of the internal space is H, the approximate width of the internal space is W, and the effective diameter of the nozzle opening is D1, the jet flow is oriented in the longitudinal direction. It is injected in the direction of the approximate center line. Suitable eddy current generation conditions are D1 <H, and W / H> 4. It is expressed by. This is an empirical formula but has theoretical basis.

The nozzle comprises a downstream flow passage and an upstream flow passage. That is, cavitation occurs in the liquid that suddenly goes out of the narrow passage into the wide passage. The effective diameter of the downstream channel is D
When the effective diameter of the upstream flow passage is represented by D2 and the effective length of the downstream flow passage is represented by L, suitable eddy current generation conditions are L / D2 ≧ 5 and D1 / D2 ≧ 2. ． It is expressed by. This is an empirical formula but has theoretical basis. More preferably, it is represented by the following formula. L / D2 ≧ 8, and 4 ≧ D1 / D2 ≧ 3. The injection port of the nozzle forming the outlet preferably has an opening shape or a circular cross section, but it does not necessarily have to be circular, and may be elliptical or polygonal.
The fluid in the present invention does not have to have a so-called streamline in its streamline, that is, it is not for rectification but for generating cavitation.
This is because it is only necessary that the vortex flow is globally synthesized.
The effective diameter D is approximately S = π (D
Squared) / 4.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION [First Embodiment of Liquid Quality Reforming Device]
Next, a first embodiment of the liquid reforming apparatus according to the present invention will be specifically described. FIG. 1 shows an embodiment of a liquid reforming apparatus according to the present invention. The liquid quality reforming apparatus 1 is composed of a turbulent flow generation box 2 and a double nozzle 3. The compound nozzle 3 is composed of a cavitation generating section 5 and a gas-liquid introducing section 6. The cavitation generation part 5 is formed in the turbulent flow generation box 2 itself, as will be described later in detail.

As shown in FIG. 2, the gas / liquid introducing section 6 is composed of a liquid introducing section 7 and a gas introducing section 8. The gas-liquid introducing section 6 is fixed to the turbulent flow generation box 2. The fixing means for fixing is, for example, a bolt hole 11 (see FIG. 1).
And bolts (not shown). The gas introduction part 8 is fixed to the liquid introduction part 7.

The fixing means is composed of, for example, a bolt hole 12 formed in the liquid introduction part 7 and a bolt 13 formed in the gas introduction part 8. A packing or an O-ring 10 is provided between the liquid introduction part 7 and the gas introduction part 8 in order to prevent liquid leakage from between the removable liquid introduction part 7 and the gas introduction part 8. ing.

By removing the gas introduction part 8 and screwing a plug (not shown) into the bolt hole 12 of the liquid introduction part 7 instead of the gas introduction part 8, the multiple nozzle 3 can be easily changed to a single nozzle. The gas-liquid introducing unit 6 as shown in the figure forms the double nozzle 3, but it can be modified to a single nozzle that ejects only the liquid. The gas introduction unit 8 is for introducing not only gas such as air and oxygen at room temperature but also liquid such as surfactant, oil, fine powder such as food, mixture of gas and liquid, and the like. is there. Therefore, the gas introduction unit 8 here does not mean that only gas is introduced.

The internal space V in the turbulent flow generation box 2 is approximately
It is a flat rectangular parallelepiped. The physical and geometric significance of flat is
It will be described in detail later. The turbulent flow generation box 2 whose axial center line is the longitudinal centerline CL passing through the center point of the internal space V has a substantially rectangular parallelepiped appearance, and includes a six-sided wall. The side wall of the turbulent flow generation box 2 is provided with a jet hole 14 having a diameter of D1. The jet hole 14 coincides with the cavitation generation part 5. The axial center line of the jet hole 14 which is the cavitation generating portion 5 coincides with the longitudinal center line CL.

The liquid introducing portion 7 has an axial liquid introducing hole 15 formed therein.
And the radial liquid introducing hole 16 is opened. The axial liquid introduction hole 15 and the radial liquid introduction hole 16 are connected at the axial center. A high-pressure liquid introduction pipe (not shown) is connected to the outer opening of the bolt hole 12. Axial liquid introduction hole 1
The above-described bolt hole 12 is formed in the extension part formed by extending 5 to the rear side. The gas introduction part 8 is inserted in the axial liquid introduction hole 15 and its extension, sharing the longitudinal centerline CL as the axis.

The gas introducing portion 8 has an axial gas introducing hole 18 which shares a longitudinal center line CL as a center line. Axial liquid introduction hole 15 and axial gas introduction hole 18
Has the same opening surface and is opened at the rear end of the jet hole 14 and connected to the jet hole 14. The width of the internal space V is shown in FIG.
Is W, the height is H shown in the figure, and the length is not particularly specified. The length direction of the internal space V is defined as the axial direction of the jet hole 14.

The height H and width W of the internal space V, the diameter D1 of the jet hole 14 and the diameter D2 of the axial liquid introducing hole 18 are shown in FIG.
4 is conceptualized and specified. A nozzle for cavitation is formed by the jet hole 14 and the axial liquid introduction hole 15. The internal space V is partially opened by an inlet corresponding to a nozzle and a discharge port 19 (see FIG. 1), but the internal space into which the high pressure fluid is introduced can be treated as a substantially closed space. it can. That is, the six-sided wall forming the rectangular parallelepiped internal space V defines the boundary condition.

As is generally known, the condition for cavitation is L / D2, especially when the liquid is water.
It can be expressed by ≧ 5. L is the axial length of the jet hole 14. This relationship is less affected by the viscous drag of the liquid. Such a relationship is a relationship (reverse relationship) that has been conventionally studied to suppress the occurrence of cavitation. In order to actively generate cavitation,
Preferably, L / D2 ≧ 8.

Furthermore, the cavitation generation condition must satisfy the following relationship. D1 / D2 ≧ 2. This relationship is also a relationship (reverse relationship) that has been conventionally studied to suppress the occurrence of cavitation. In order to positively generate cavitation, preferably 4 ≧ D1 / D2
≧ 3. Qualitatively speaking, the condition for the occurrence of cavitation is
Rapid high-pressure fluid flows from a narrow place to a wide place. Cavitation naturally does not occur where Bernoulli's theorem holds.

Cavitation flow also occurs in a wide area when the fluid is swirled like a typhoon. The countless bubbles (cavitation) created near the jet nucleus at the exit of the jet hole 14 disappear. If a swirl is generated, the birth of bubbles will continue. The shearing force of the vortex causes the bubbles to seed other bubbles. That is, the bubbles generated from the nozzle become seeds and reproduce the bubbles in the vortex.

As is known, the vortex generation condition is that the size of the space forming the turbulent flow generation section is D1 <H and W is W.
/ H> 4. That is, when the height H is large, the vortex does not continue even if it occurs once and is immediately destroyed and disappears.
This is because the vortex having angular momentum is not stable in the three-dimensional space but stable in the plane. As will be described later, the central region of such a vortex orbits in a plane orthogonal to the height direction along substantially the entire inner space along the four-sided wall excluding the upper and lower two-sided walls. That is, the whole liquid in the inner space has a slow angular angular momentum as compared with the rotational speed of the vortex center, while a part of the liquid is discharged from the discharge port.

It is effective that the internal space forming the turbulent flow generating section is substantially flat. It is also possible to replace the single type nozzle with a double type nozzle, introduce air bubbles into the liquid by the gas introduction unit 8, and mix the air bubbles in the cavitation flow. In situations where cavitation is occurring,
The pressure gradient becomes extremely large spatially in the region around the bubbles, and the decomposition / separation of substances dissolved in the liquid near the cavitation bubbles, mixing / emulsification / agitation, gas separation, and conversely gas such as oxygen Can also be dissolved.

The liquid reforming apparatus according to the present invention is used together with a high pressure pump. A plunger type pump is suitable as the high-pressure pump so that the pressure near the outlet can be increased. The supply pressure to the nozzle is 2 kg / m depending on the application and effect.
Select from the range of m ² or more. Desirably, deaeration of chlorine in tap water is 2 Kg / mm ² or less, and stirring, mixing, separation,
Sterilization should be less than 10 kg / mm ² , degassing and sterilization should be 30 kg / mm ^2.
The following is sufficient, and the decomposition of organic substances such as trichlorethylene and dioxin is preferably 100 Kg / mm ² or more.

The liquid reforming apparatus 1 can form a cavitation vortex by designing the internal space such that its width is about 7 cm, its length is about 15 cm, and its height is about 2 cm. FIG. 21 is an abstract view abstracting a photograph of a spouted bed in which cavitation has occurred in the turbulent flow generation box 2, taken with a high-speed camera. The direction of rotation of the vortex is determined by the initial condition due to the slight asymmetry of the nozzle orientation, and the orientation of its spin axis is preserved by the law of conservation of angular momentum of the whole system. The vortex has a central portion 31. The central portion 31 moves on a closed trajectory line 32 that is oriented in a certain direction. For example, it makes one round on the trajectory line 32 in 2 seconds.

FIG. 22 shows a state in which the central portion 31 of the vortex moves along the locus line 32 shown in FIG. The cavitation bubble is also in its vortex before contracting and expanding and especially expanding and collapsing. The physical activity (pressure fault) of such bubbles performs actions such as destruction of cell membranes of bacteria in the liquid, decomposition of substances, mixing, and miniaturization. In addition, dissolved gas in the liquid, such as methane and other organic solvents, and impure gas such as chlorine, which are induced by rapid expansion of bubbles, spring out to the pressure fault, evaporate into the bubbles, and are discharged from the discharge port 19 to lower the pressure. In the state, it is released into the atmosphere. A violent vortex is generated around the center of the vortex that circulates in the internal space V, and the vortex uniformly stirs the liquid in the space.

Next, in order to facilitate understanding of cell destruction of cavitation, a theoretical background will be described for reference. It has long been known that a jet flow is described by a motion equation based on shear stress (Reynolds stress). The specific theory development has been carried out by the present inventor (published).

FIG. 5 is a plan sectional view for analyzing a free vortex jet discharged from a nozzle into a vacuum. The x-axis is set so as to match the center line of the virtual nozzle 51 (which is formed on the conical surface near the ejection port for virtualization). The y-axis is set in the direction in which the jet flow spreads, that is, in the direction orthogonal to the direction of travel of the jet center. Therefore, the coordinate system xy is a Cartesian coordinate system. The tip of the conical jet core 52 is generated where the conical surface of the nozzle 51 is extended and the surfaces intersect. The spread of the jet flow at a position X sufficiently distant from the jet flow core 52 is shown by b. As an empirical formula, b = k # j · x (1) In this specification, the subscript right subscript is preceded (#) by #. k # j is called a jet flow spread coefficient and is an important basic factor of jet flow characteristics.

In case of having the eddy current characteristic, b = 24k · x (2) The constant k is a coefficient representing the eddy current characteristic. The shear stress τ is expressed by the following expansion formula, that is, a polynomial.

[0042]

[Equation 1] The coefficient C # n is determined from the shear stress for the boundary condition of the equation of motion. Applying Prandtl's assumption regarding Reynolds stress, the velocity distribution is expressed by the following equation in the approximation equations up to the fourth order.

[0043]

[Equation 2] The equation (3-1) derived from the condition of the shear stress can be applied to both two-dimensional and three-dimensional flows of a free jet and a constrained jet. The value of η for which the right side of Expression (3-1) is 0 is 1
Therefore, the jet velocity becomes zero at a position separated from the x axis by a certain distance.

When the liquid is discharged into the infinite space from the nozzle 51 having the finite exit cross-sectional area of the diameter D, the velocity attenuation of the jet flow without a pressure gradient, that is, on the center axis, is

[Equation 3]

Since the velocity at the nozzle outlet is zero on the central axis, the velocity increases sharply after the outlet, and as shown by the arrow in FIG. Velocity vectors at positions distant from appear symmetrically. The jet flow is divided into a range up to the length X # c of the jet nucleus, that is, an initial region 53 and a region on the downstream side thereof, that is, a main region 54. Calculating for reference, the length of the jet nucleus is

[Equation 4]

Equations (4,5) follow Albertson's experimental results. From equation (4, 5), the length of the jet nucleus X #
c is obtained, and the jet spread coefficient k # j of the equation (1) is obtained from the equation (6). Therefore, the coefficient k of the equation (2) can also be obtained. Experimentally, the jet core length X # c is obtained by measuring the jet center velocity u # m, and the jet width b and the jet spread coefficient k # j are obtained.

The cavitation phenomenon in an underwater high-speed water jet can be considered under the above analysis. Rous
From the viewpoint of the eddy current characteristics of the air flow jet due to e, it can be estimated as follows. The eddy viscosity coefficient ε of the free jet is ε = kbu # m .... (7) The coefficient k related to the eddy current characteristics is based on Prandtle's assumption.

[Equation 5]

From equations (8, 9), b is proportional to x and u #
a three-dimensional flow in which m is inversely proportional to x (relationship of equation (4)), and b
Is proportional to x and u # m is inversely proportional to the square root of x (relationship of equation (5)).
1) is obtained. The coefficient k can be calculated from the energy equation.

[0049]

[Equation 6] The Reynolds stress τ closely related to the cavitation phenomenon is

[Equation 7] When the eddy current diffusion coefficient χ is large, energy diffusion that causes a cavitation effect is likely to occur. The jet spread coefficient k # j directly affects the promotion of the cavitation effect so that the jet spread coefficient k # j linearly appears in the equations (10, 11). This means that when the jet flow is constrained by the wall around the nozzle, the magnitude of the jet flow expansion coefficient k # j changes.

A jet model having a horn-shaped side wall is known as a model for causing a constrained jet flow.
As shown in FIG. 6, when the jet flow spread coefficient k # j in the case where the conical surface side wall shown by the dotted line, that is, the constraining wall 55 is calculated, it is three-dimensional and

[Equation 8] This is the same in the two-dimensional case. The significance of the equation (12) is that the relationship between the jet spread coefficient k # j and the side wall angle θ # w can be obtained. For a two-dimensional flow in a flat rectangular box and a three-dimensional flow in a cylindrical box, the maximum jet velocity u
#M has a difference in whether it attenuates at the square root of x or in proportion to x. In the present invention, a two-dimensional flow formed in a flat box is used so that the attenuation is small. There is. Moreover, the two-dimensional flow has good stability as described above.

When the cavitation initiation coefficient σ # i is shown in the graph from the equations (10) and (12), the maximum value is obtained in the vicinity of θ # w of 30 degrees as shown in FIG. This graph is quoted from the experimental report of Numachi (Saiken report, Vol. 16, 1960-1961, No. 158, No. 159). Theoretical analysis quoted as above in this specification ("Basic Characteristics of Jet", Jet Engineering Vol.
12, No. 2, 1995, 23-32) by Yanagida (Mashita), which shows a good agreement between theory and experiment.

FIG. 8 shows the relationship between the ratio of D and d and the cavitation initiation coefficient σ # i shown in the figure. That is, the cavitation initiation coefficient σ # i is the ratio (D / d)
(This is the maximum when D1 / D2 in FIG. 3) is around 3. Therefore, when D1 is 3 times the unit length, L is preferably 8 times the unit length. It is empirically preferable to set the following for the double nozzle.

[0053]

[Equation 9] Here, d1 and d2 are the inner diameter and the outer diameter of the plurality of nozzles (see FIG. 2). If d2 is zero, in such a case, it is preferable to be expressed by the following equation, for example.

[0054]

[Equation 10] Regarding the width B and the height A, naturally,

[Equation 11] Here, A corresponds to W in FIG. These conditions assume that the Reynolds number is 2300 or more. From these equations, the range of absolute values of those values is determined. Considering only the cavitation effect, the values W, B, H may be small, but the volume of the box needs to be large to some extent in consideration of the motion of the vortex flow and the purification efficiency.

The adhering distance X # R of the jet flow is expressed by the following equation using d in FIG. 9, the jet spread coefficient k # j and the side wall angle θ # w.

[Equation 12] For reference, the calculation results are as follows:

[Equation 13]

FIGS. 9 and 10 show experimental results showing "cavitation erosion"("Hydraulics of Pipelines", J.
Paul Tullis, JOHN WILEY & SONS, 1989, P17
It is a quotation from 0). X # cp indicates the x-coordinate in the middle of the cavitation erosion occurrence area, that is, the cavitation pitching zone. Figure 10
The relationship between the coordinates of the maximum ultrasonic wave generation position and the side wall angle θ # w is shown. From these both experimental results, it is supported that the existence of the specific area where cavitation erosion occurs is substantially coincident with the existence of the specific area of ultrasonic wave generation.

9 and 10, the core length X # c obtained by the square study is also shown. As shown in FIG. 10, the maximum position of the cavitation ultrasonic wave substantially matches the square core length. As shown in FIG. 9, the collapse experiment of the orifice cavitation corresponding to the rapid expansion is almost in agreement with the square study. The cavitation effect in which the shear stress τ, the vortex diffusion coefficient χ, and the jet core length are closely related is promoted by giving an appropriate dimension to the nozzle shape and the box shape.

The shape of the nozzle is classified by type as shown in FIGS. 11 to 14, but the present invention is in principle independent of the type of the nozzle type. The nozzle 23 with the smallest diameter shown in FIG. 14 in which the small-diameter jet hole is opened on the side wall surface at right angles to the axis of the cylindrical container, and the wall surface at right angles to the axis of the nozzle 23 of FIG. The nozzle 22 shown in FIG. 11 is a compromise between the nozzle shown in FIG. 13 and the nozzle shown in FIG. 14, and the conical surface is formed following the wall surface perpendicular to the axis. The nozzle shown in FIG. 12 in which the jet hole itself forms the conical surface. It can be classified into four types of 21.

As described above, the cavitation generation region, the degree thereof, etc. can be globally analyzed from the equation of motion of shear stress based on the momentum distribution described on the coordinate system with the core nucleus as a unit, and the analysis is simple. Was shown. Next, a local study on one cavitation bubble is also necessary.

There is also a noteworthy report on the relationship between the air content rate and the cavitation initiation coefficient. 12th International Towing
According to the experimental report presented at the Tank Conference (ITTC),
This means that if the state of cavitation nuclei contained in experimental water is different, the state of cavitation generation changes significantly. Fig. 15 (Cavitation-Nuclei Me, R. Oba et al.
asurements by a Newly Made Coulter-Counter without
Adding Salt in Water, Rep. Inst. High Speed Mech.,
Tohoku University, Sendai, 43-340 (1981), 173)
Shows the relationship between the diameter of the underwater nuclei in tap water (air nuclei, chlorine nuclei, etc.) and the number of nuclei. The distribution of the nuclear diameter and the number 24 hours after the collection has changed greatly. Thus, the existence of cavitation nuclei in tap water is not stable.

FIG. 16 (Numachi's study) shows the relationship between the number of air nuclei in water (number density distribution), the air content related to the nucleus diameter, and the initiation cavitation coefficient K. Regardless of temperature change, air content can significantly affect the primary cavitation coefficient (the definition is detailed in Ryoji Kobayashi: Cavitation, Water Jet, 1-2 (1984, 1-13)). Clearly shown. The molecule of air content α / α # s is the actual air content,
α # s represents the saturated air content.

Cavitation looks like a white cloud when observed with the naked eye, but it can be seen from high-speed photographs and instantaneous photographs that it is formed of moving bubbles and cavities fixed on the solid surface. Looking at the time variation of the bubbles, the bubbles have a lifetime, have a growth period and an extinction period, and sometimes have a rebound process after the extinction. Rayleigh's theory (1
According to 917), if one spherical vapor bubble exists in a sufficiently wide static space, the maximum pressure generated in the vicinity of the bubble when the bubble disappears from the initial radius R # 0 to the radius R. The value p # max is expressed by the following equation.

[0063]

[Equation 14] p # ∞ is the pressure of the surrounding space. If the bubble radius R becomes 1/20 of the initial radius, the maximum pressure is 1280 times the pressure in the surrounding space. The theoretical value of the radial pressure distribution p (r) and its change over time when one vapor bubble containing a small amount of gas disappears and rebounds, and a sudden pressure rise that appears to be a shock wave appears during the rebound period. .

This has been confirmed by schlieren photography. The impact pressure generated during the bubble disappearance / rebound period has been recognized as an important cause of the mechanism describing cavitation erosion. One of the causes is the microjet theory that the microjet is formed inside the disappearing cavitation bubble.

FIG. 17 shows a numerical simulation of the extinction process of a spherical bubble on the surface of a solid, showing how a microjet formed in the bubble hits the surface of the solid. Such a phenomenon has also been confirmed by experiments.

The study of cavitation has been conducted from the viewpoint of material damage, cleaning of solid surface, etc., but it is effective by combining the shock pressure fluctuation at the time of cavitation collapse with the cavitation effect by the positive introduction of air. It has never been done for the technical means of destructive purification and separation. The impact pressure of the cavitation bubbles uniformly dispersed and diffused can effectively destroy cells and effectively separate gas and liquid.

The jet nuclei are also generated by the rotation of the rotor blades.
In this case, the air can draw the air into the jet stream generated from the surface of the rotor blade through the hole formed in a part of the hollow rotor blade. The effectiveness of cell disruption is less affected by air introduction. Spatial and temporal pressure gradient (dP / dx.
・ Depends heavily on dP / dt). Cavitation occurs around the core described above, which is formed on the downstream side from the nozzle ejection port. The amount of cavitation and the shape and distribution of the core are not directly related. The amount of cavitation increases when a fluid flows out at a high speed from a small-diameter opening to an ejection hole having a diameter larger than the diameter of the opening.

FIG. 18 shows a known representative example of a stationary water jet nozzle. This is a nozzle designed with attention to the angle (10 ° to 14 °) of the nozzle constriction part and the ratio (4 times) of the length of the circular pipe part of the outlet to the diameter of the outlet (d0), and to prevent the occurrence of cavitation. Is taken into consideration. On the contrary, FIGS. 19 and 20 show a nozzle designed to promote the occurrence of cavitation.

FIG. 19 shows a nozzle which produces a large amount of cavitation when it suddenly goes out to a wide area from an ejection port narrowed by a rod 81 and an opening 82.
FIG. 20 shows a state in which the flow is restricted by a narrow jet and a ring-shaped (torus-shaped) cavitation bubble is generated. Rather, as shown in the nozzles of FIGS.
It is advantageous for the occurrence of cavitation that there is no obvious jet core.

As for the cavitation, in addition to the nozzle dependent type generated behind the jet core seen in the mathematical analysis described above, both the vortex dependent type generated by the shear stress in the vortex flow are considered. Need to Deaeration,
Experiments have shown that the latter is effective for mixing, sterilization, decomposition and the like. It is presumed that the former greatly affects the occurrence of the latter. The shear stress of eddy current may have a great influence on cell destruction independently of cavitation. As described above, it cannot be denied that the jet nucleus-dependent cavitation and the vortex-dependent cavitation occur, or the conditions that cause them are important factors for cell destruction.

[Second Embodiment of Liquid Quality Reforming Device] In the first embodiment, the turbulent flow generation box 2 of the liquid quality reforming device 1 is flat and box-shaped, and the internal space is a rectangular parallelepiped. It had a hollow space. Although this shape efficiently generates cavitation as described above, it does not necessarily have to be this shape. 23 shows the second embodiment of the liquid quality reforming apparatus, and is an example in which the internal space of the turbulent flow generation section is formed into a cylindrical shape. Disc-shaped flanges 29 are arranged at both ends of the cylindrical main body 30, and the cylindrical main body 30 is inserted into a groove 33 formed in this end surface.

The two flanges 29 and the cylindrical body 30 are connected to each other by bolts 34 and nuts 35 and fixed to each other. The double nozzle 3 having the same shape as that of the first embodiment is arranged and fixed on the side surface of the one flange 29. On one of the flanges 29, a cavitation generating part 5 which is a cylindrical through hole is formed. As shown in FIG. 23, the gas-liquid introducing section 6 is composed of a liquid introducing section 7 and a gas introducing section 8, but the principles and functions of these are substantially the same as those in the first embodiment. Therefore, the description thereof is omitted. However, as in the case of the above-described first embodiment, the gas introduction part 8 does not have to be closed and used.

A discharge port 36, which is a through hole, is formed at the center of the other flange 29. Furthermore, another flange 2
One end of the discharge guide tube 36a is fixed to the side surface of the sheet 9. The turbulent flow generation chamber 37, which is a cylindrical space in the cylindrical body 30.
Forms a space for collapse of cavitation bubbles and turbulent flow such as vortex flow. The turbulent flow generation chamber 37 performs physical and chemical actions such as sterilization, insecticide, deaeration, emulsification and mixing.

[Third Embodiment of Liquid Quality Reforming Device] FIG. 24
Shows the third embodiment of the liquid reforming apparatus, in which the turbulent flow generation chamber 3
7 is the same as the third embodiment, but the mechanism for generating cavitation is different. This is an example in which an axial liquid introduction hole for conducting liquid and a cavitation generating portion are arranged in the turbulent flow generating chamber 37. The axial liquid introduction hole 38 allows the pressurized liquid to pass therethrough, and ejects the liquid to the cavitation generating portion 39 formed concentrically to generate cavitation. This type of cavitation nozzle 40
Unlike the first and second embodiments, the single nozzle type is used, and gas cannot be mixed. Cavitation nozzle 4
Since 0 projects inward, there is a feature that the whole becomes compact.

[Fourth Embodiment of Liquid Reformer] FIG. 25
Shows the fourth embodiment of the liquid quality reforming apparatus, and the cavitation nozzle 40 and the turbulent flow generation chamber 37 are the same as those of the third embodiment, except that the cavitation nozzle 40 can be moved to any position. Cavitation nozzle 40
Is fixed by being screwed into one end of the connecting fitting 41, and the other end of the connecting fitting 41 is connected to the position adjusting tube 42. The position adjusting tube 42 is a fixing screw 4 screwed into the flange 29.
It is fixed to the flange 29 by 3.

The position adjusting tube 42 is slidably arranged in an insertion hole 44 formed at the center of the flange 29. Therefore, by loosening the fixing screw 43, the position adjusting tube 4
2 can be moved to fix the cavitation nozzle 40 at an arbitrary position of the cavitation generating section 39. In the turbulent flow generation chamber 37, the cavitation bubbles collapse,
And a space for generating a turbulent flow such as a vortex. The turbulent flow is for adjusting the position of the cavitation nozzle 40 on site because the efficiency of cavitation generation differs depending on the position of the cavitation nozzle 40.

[Fifth Embodiment of Liquid Quality Reforming Device] FIG.
Shows a fifth embodiment of a liquid quality reforming apparatus, and is a liquid quality reforming apparatus 60 when applied to reforming seawater of a land fish farming apparatus.
Is. The turbulent flow generation box 61 has a flat rectangular parallelepiped shape similar to that of the first embodiment. A turbulent flow generation chamber 62 is formed inside the turbulent flow generation box 61. The turbulent flow generation box 61 has the outline described above, but the inside of the curved portion 6 is formed in order to cause cavitation and smooth vortex flow.
3 is formed.

A flange 64 is provided on the end surface of the turbulent flow generation box 61.
Are fixed by bolts 65. One surface of the turbulent flow generation box 61 is covered with a cover member (not shown) as in the first embodiment. An injection nozzle 66 for injecting pressurized seawater is fixed to the flange 64. In the turbulent flow generation box 61 in the injection direction of the injection nozzle 66, a cavitation generation part 67 having a cylindrical space in cross section is formed.

A discharge port 68 communicating with the turbulent flow generation chamber 62 is formed in the turbulent flow generation box 61 on the opposite side where the injection nozzle 66 is arranged. The discharge nozzle 6 is provided at the discharge port 68.
One end of 9 is screwed in and fixedly arranged. One end of the connector 70 is fixed to the other end of the discharge nozzle 69.
One end of an air pipe 71 is screwed into the connector 70 in a direction orthogonal to the discharge direction of seawater discharged from the discharge nozzle 69.

The air pipe 71 is for drawing in air by the negative pressure of seawater discharged from the discharge nozzle 69. A pipe joint 72 is screwed into the other end of the connector 70. Therefore, seawater containing air is discharged from the tip of the pipe joint 72. With the structure as described above, the liquid quality reforming device 60 has the following functions. The cavitation is generated in the cavitation generation part 67, and the seawater injected from the injection nozzle 66 enters the turbulent flow generation chamber 62.

The seawater that has entered the turbulent flow generation chamber 62 generates turbulent flows such as cavitation bubbles and vortexes as described above. Ammonia, nitrogen nitrate, carbon dioxide, chlorine, oxygen, etc. in seawater are degassed by the cavitation action. Further, it destroys, sterilizes and kills fish parasites, parasite eggs, larvae, Escherichia coli, etc. in seawater. The cavitation-processed seawater is discharged from the discharge nozzle 69, and the negative pressure due to this discharge sucks the air in the atmosphere from the air pipe 71 and mixes it with the seawater.

The cavitation-treated seawater mixed with air is discharged from the pipe joint 72 to a seawater tank (not shown). At this time, the fine bubbles that have been degassed by the cavitation process and are discharged are discharged into the air together with the air sucked from a large amount of the air pipe 71. For this purpose, the ammonia, nitrogen nitrate, carbon dioxide, chlorine, oxygen, etc. in the seawater described above are degassed. However, since a large amount of air is sucked in at the same time, the dissolved oxygen amount useful for fish farming does not balance and decrease.

Further, there is also an effect of slightly cooling the seawater that has risen due to the inclusion of air. By mixing this air with seawater, a gas harmful to the fish deaerated in the turbulent flow generation chamber 62 can be effectively released into the atmosphere. as a result,
The PH value of seawater was close to that of natural seawater (8.3). Table 1 below shows a representative example of these data.

[0084]

[Table 1]

INDUSTRIAL APPLICABILITY The liquid quality reforming apparatus according to the present invention can effectively perform deaeration, mixing, stirring, sterilization, insecticidal, decomposition, emulsification, etc. by cavitation and its vortex flow. Further, the present invention can be formed only by a container and a cavitation nozzle that form a simple closed space, and the cost is extremely low.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an embodiment of a liquid quality reforming apparatus of the present invention.

FIG. 2 is a front sectional view of FIG.

FIG. 3 is a plan view abstracted and traced from a high-speed photograph of an eddy current at a certain moment.

FIG. 4 is a plan view abstracted and traced from a high-speed photograph of a vortex flow one second after the instant of FIG.

FIG. 5 is a cross-sectional view showing a coordinate system for jet flow analysis.

FIG. 6 is a cross-sectional view showing a coordinate system for jet analysis with respect to a restrained jet model.

FIG. 7 is a graph showing the relationship between the nozzle opening shape and the cavitation initiation coefficient.

FIG. 8 is a graph showing a relationship between a sudden expansion nozzle and a cavitation initiation coefficient.

FIG. 9 is a graph showing the relationship between cavitation erosion and jet core length.

FIG. 10 is a graph showing the relationship between the cavitation ultrasonic maximum value position and the jet core length.

FIG. 11 is a cross-sectional view showing an example of a nozzle shape.

FIG. 12 is a cross-sectional view showing another example of the nozzle shape.

FIG. 13 is a cross-sectional view showing still another example of the nozzle shape.

FIG. 14 is a cross-sectional view showing still another example of the nozzle shape.

FIG. 15 is a graph showing the relationship between the diameter of the nucleus and the number thereof.

FIG. 16 is a graph showing the relationship between the air content rate and the initiation cavitation coefficient.

FIG. 17 is a graph showing the occurrence and disappearance of cavitation.

FIG. 18 is a cross-sectional view showing a known nozzle for generating a stationary jet.

FIG. 19 is a cross-sectional view showing a known nozzle for generating an unsteady jet.

FIG. 20 is a cross-sectional view showing another known nozzle for generating an unsteady jet.

FIG. 21 is a plan view showing one dynamic of vortex flow.

FIG. 22 is a plan view showing another dynamic state of the vortex flow.

FIG. 23 shows a second embodiment of the liquid quality reforming apparatus, and is an example in which the internal space of the turbulent flow generation portion is formed into a cylindrical shape.

FIG. 24 shows Embodiment 3 of the liquid quality reforming apparatus, and is an example in which the shape of the nozzle of Embodiment 2 of the liquid quality reforming apparatus is changed.

FIG. 25 shows Embodiment 4 of the liquid quality reforming apparatus, and is an example in which the shape of the nozzle of Embodiment 3 of the liquid quality reforming apparatus is changed.

FIG. 26 shows Embodiment 5 of a liquid quality reforming apparatus, which is a liquid quality reforming apparatus when applied to reforming seawater of a land fish farming apparatus.

[Explanation of symbols]

1. Liquid quality reformer 2 ... Turbulence box 3 ... Compound nozzle 5 ... Cavitation generation part 6 ... Gas-liquid introduction section 7 ... Liquid introduction part 8 ... Gas introduction section 14 ... Jet hole 15 ... Axial liquid introduction hole CL ... longitudinal center line 62, 37 ... Turbulent flow generation chamber 40 ... Cavitation nozzle 67 ... Cavitation generation part 69 ... Discharge nozzle 71 ... Air tube

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hidenori Okuma 1534, Karatsu Ichihara, Saga Prefecture, WIBM Co., Ltd. (72) Inventor, Mamoru Tanaka 1534, Karatsu Ichihara, Saga Prefecture (56) Reference, JP 11-47785 (JP, A) JP-A 5-212317 (JP, A) JP-A 8-257998 (JP, A) JP-A 2-56296 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) B01J 19/08-19/10 C02F 1/34 C02F 1/20 B01D 19/00 B05B 1/02

Claims (6)

(57) [Claims] 1. Cavitation generating means for injecting a pressurized liquid to generate cavitation, said liquid ejected from said cavitation generating means is formed as a jet flow, and said jet flow becomes a dynamic vortex flow. A turbulent flow generating means having a substantially closed space, an outlet for discharging the liquid from the turbulent flow generating means, and a central region of the dynamic vortex that moves in the space. The motion is a periodic motion in the space, the turbulent flow generating means is flat in a three-dimensional space, the approximate height of the space is represented by H, and the approximate width thereof is represented by W, When the effective diameter of the opening of the nozzle is represented by D1, the jet flow is ejected in the direction of the approximate centerline of the space in the longitudinal direction, and the vortex generation condition is D1 <H and W / H> 4 Liquid reformation and wherein the door. 2. The liquid reforming apparatus according to claim 1, wherein the cavitation generating means is formed as a nozzle for ejecting only the liquid. 3. The nozzle according to claim 1 or 2, wherein the nozzle comprises a downstream channel and an upstream channel, the effective diameter of the downstream channel is D1, and the effective diameter of the upstream channel is D2. When the effective length of the downstream side flow path is represented by L, the eddy current generation condition is L / D2 ≧ 5 and D1 / D2 ≧ 2. 4. The nozzle according to claim 3, wherein the nozzle comprises a downstream channel and an upstream channel, the effective diameter of the downstream channel is D1, and the effective diameter of the upstream channel is D2. When the effective length of the downstream side flow path is represented by L, the eddy current generation condition is L / D2 ≧ 8 and 4 ≧ D1 / D2 ≧ 3. 5. The nozzle according to claim 4, wherein the nozzle comprises a downstream flow passage and an upstream flow passage, the height of the space is represented by H, and the width of the space is represented by W. the effective diameter of the passage effective diameter of the upstream passage expressed by D1 in D2 Table strike, the jet stream is injected in the direction of the approximate center line of the space facing in a longitudinal direction, of the vortex The liquid-quality reforming apparatus, wherein generation conditions are D1 <H and W / H> 4 and L / D2 ≧ 5 and D1 / D2 ≧ 2. 6. The liquid-quality reformer according to claim 1, which is used to degas the dissolved gas in the liquid.