JP2002045667A - Circulating flow generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circulating flow generator capable of efficiently dissolving oxygen in a liquid with a small amount of energy, generating a stable circulating flow, and purifying the liquid effectively. SOLUTION: A pipe 1 installed in water is provided with a flow path 3 surrounded by a cylindrical wall surface 11, and a gas blowing hole 5 is formed at an acute angle with respect to the traveling direction of water (arrow a). It is provided obliquely and in a horizontal section in a tangential direction of the wall surface 11. Liquid outlet 7
Are provided so as to extend. Compressor 2
3 generates high-pressure air and passes through the gas blowing holes 5
Blow into channel 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circulating flow generator capable of making a gas fine, mixing and dispersing the same in a liquid, dissolving the liquid efficiently, and forcibly circulating the upper and lower layers of the liquid over a wide range. It is about.

[0002]

2. Description of the Related Art For purifying closed water areas such as dams, lakes, inland seas, etc., methods such as removal of basic nutrients, ultraviolet sterilization, fountain type, and underwater aeration type are used. Requires a huge amount of energy.

In such conventional equipment, purification has not always been successful. The cause is that, in the case of conventional underwater aeration, purification in closed waters requires
There are very few examples that can be solved simply by increasing dissolved oxygen,
Although it is necessary to lower the surface water temperature by ion activation or ascending flow generated by a strong stirring effect, these measures are insufficient.

[0004] The fact that pollution of dams, lakes, and enclosed sea areas is becoming more and more serious can be said to indicate the deficiencies of conventional purification facilities. In other words, many of the conventional purification facilities are intended for ad hoc measures, and are not drastic or permanent measures.

[0005] Therefore, as another purification method, a spiral plate with a twist is arranged in a pipe, and this spiral plate allows
A method was considered in which the swirling motion was given to the water flowing through the air to mix the blown air with the water.

[0006]

However, the method using the spiral plate is more effective for gas-liquid mixing than the conventional aeration method, but has the following problems.
It was not practical.

(1) The existence of the spiral plate acts as a kind of baffle plate, in which suspended matter in the liquid accumulates and hinders the flow of the liquid (generation of a circulating flow). Here was the biggest problem.

(2) Since the oxygen dissolving efficiency is extremely low, about 0.5% to 2%, and the structure requires a large amount of air injection, it can be used only within the range of the maximum water depth of about 5 m. .

In view of the above points, the present invention provides a circulating flow generator capable of efficiently dissolving oxygen in a liquid with a small amount of energy, generating a stable circulating flow, and effectively purifying the liquid. The purpose is to provide.

[0010]

According to the circulating flow generator of the present invention, a gas-liquid mixing means installed in a liquid for mixing a gas and a liquid, a gas blowing means for blowing a gas into the gas-liquid mixing means, and The gas-liquid mixing means is surrounded by a cylindrical wall surface, a flow path into which gas is blown from the gas blowing means, a liquid discharge port provided at one end of the flow path, and a gas discharge port for blowing gas into the flow path. And a gas discharge hole, wherein the liquid discharge port is provided so as to be divergent, and the gas blow hole is, at a vertical cross section, obliquely inclined at an acute angle with respect to the direction of travel of the liquid in the flow path, and In the horizontal cross section, the gas is provided so as to have a tangential component of the wall surrounding the flow path, and the gas contains at least oxygen.

With this configuration, oxygen can be efficiently dissolved in the liquid with little energy, a stable circulating flow can be generated, and the liquid can be purified effectively.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The circulating flow generator according to the first aspect of the present invention includes a gas-liquid mixing means and a gas blowing means.
The gas-liquid mixing means is provided in the liquid and mixes the gas and the liquid. The gas blowing means blows gas into the gas-liquid mixing means. This gas contains at least oxygen.

This gas-liquid mixing means includes a flow path, a liquid discharge port, and a gas blowing hole. The flow path is surrounded by a cylindrical wall surface, and a gas containing oxygen is blown from a gas blowing means. The liquid discharge port is provided at one end of the channel. The gas blowing hole is for blowing a gas containing oxygen into the flow path.

This liquid discharge port is provided so as to be divergent. The gas blowing hole, in the vertical section,
It is provided so as to be inclined at an acute angle with respect to the traveling direction of the liquid in the flow path, and to have a tangential component of a wall surface surrounding the flow path in a horizontal cross section.

As described above, according to the present invention, the gas blowing hole has a component tangential to the wall surface surrounding the flow path so as to be inclined at an acute angle with respect to the traveling direction of the liquid in the flow path. The gas is blown into the flow channel through the gas blowing hole to generate a swirl flow in the flow channel, thereby simultaneously generating the circulating flow and the gas-liquid mixing.

As described above, instead of separately providing a mechanism for mixing a gas with a liquid and a mechanism for generating a circulating flow, a mechanism for mixing a gas with a liquid also has a mechanism for simultaneously generating a circulating flow. Has become. For this reason, gas-liquid mixing and generation of a circulating flow can be simultaneously realized with little energy. Further, since nothing is provided in the flow path such as a spiral plate as in the conventional case, a stable circulating flow can be generated.

In addition to such an effect, by providing a liquid discharge port so as to spread out, a shear force can be applied.
Promotes dissolution of gas into liquid.

Therefore, in the present invention, generation of a stable circulating flow and efficient dissolution of oxygen in a liquid are simultaneously realized with a small amount of energy. Therefore, the liquid can be effectively purified with a small amount of energy.

In the circulating flow generator according to the second aspect, the opening angle of the liquid discharge port is set to 50 degrees or more and 70 degrees or less.
By doing so, a stronger shearing force can be generated, and the dissolution of oxygen in the liquid can be further promoted.

[0020] In the circulating flow generating device according to the third aspect, the gas blowing hole is provided in the flow direction of the liquid in the flow path.
It is provided so as to be inclined at an angle of 10 degrees or more and 80 degrees or less. By doing so, a stronger swirling flow can be generated, so that a stronger circulating flow can be generated.

According to a fourth aspect of the present invention, the gas blowing hole is provided in a tangential direction of a wall surrounding the flow path. By doing so, a stronger swirling flow can be generated, so that a stronger circulating flow can be generated.

In the circulating flow generator according to the fifth aspect, a plurality of gas blowing holes are provided, and are provided so as to blow gas in a circulating direction along a wall surrounding the flow path. By doing so, a stronger swirling flow can be generated, so that a stronger circulating flow can be generated.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, a characteristic portion of a circulating flow generator according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a vertical sectional view of a characteristic portion of the circulating flow generator according to the present embodiment, and FIG. 2 is a horizontal sectional view of the same. 1 and 2, the same portions are denoted by the same reference numerals.

As shown in FIGS. 1 and 2, a flow path 3 surrounded by a cylindrical wall surface 11 is formed in a pipe 1 which is a characteristic part of the circulating flow generator. And
A liquid discharge port 7 is provided at one end of the flow path 3 so as to be divergent (frustoconical shape), and the other end is a liquid suction port 9.

The pipe 1 has four gas injection holes 5 formed therein. Specifically, the gas injection hole 5
In the vertical cross section of the pipe 1, as shown in FIG. 1, the pipe 1 is provided so as to be inclined at an acute angle (at an angle θ 1) with respect to the traveling direction of the liquid in the flow path 3 (the direction of arrow a). Further, in the horizontal cross section of the pipe 1, the gas blowing hole 5 is formed in the tangential direction of the wall surface 11 as shown in FIG.

Although an "external thread" is formed on the outer surface of the pipe 1 as described later, it is omitted in FIGS. 1 and 2. The pipe 1 corresponds to a gas-liquid mixing unit.

Next, the principle of the circulating flow generator according to the present embodiment will be described. First, the pipe 1 is placed in a liquid (for example, underwater). In this case, the pipe 1 is installed such that the liquid discharge port 7 faces the surface of the liquid (the liquid suction port 9 of the pipe 1 faces the bottom of the liquid).

After the apparatus is installed as described above, when a high-pressure gas containing oxygen is blown into the flow path 3 through the gas blowing hole 5 as shown by an arrow b, the liquid flowing from the liquid suction port 9 is turned on. Flows through the flow path 3, is mixed with the gas blown from the gas blowing hole 5, and is discharged upward from the liquid discharge port 7. As a result, a gas-liquid mixed circulation flow as shown by an arrow c is generated, and the liquid is purified.

Hereinafter, the mechanism of generation of such a gas-liquid mixed circulation flow will be described in detail. The high-pressure gas blown into the flow path 3 from the gas blow-in hole 5 becomes bubbles and rises while turning along the wall surface 11 of the pipe 1. The liquid is entrained in the swirling flow of such bubbles, is sucked from the liquid suction port 9 by the ejector effect, and mixes with the swirling flow and rises.

In this process, the injected gas and the liquid are mixed violently, and the gas (oxygen) is dissolved in the liquid. As a result, a flow in the direction of arrow a is formed in the flow path 3, and a large gas-liquid mixed circulation flow as shown by arrow c is formed.

As described above, in the present embodiment, a mechanism for mixing a gas with a liquid (a mechanism for dissolving oxygen in a liquid),
The mechanism for generating a circulating flow is not provided separately, but a mechanism for mixing a gas with a liquid is also a mechanism for generating a circulating flow. For this reason, gas-liquid mixing (dissolution of oxygen in a liquid) and generation of a circulating flow can be simultaneously realized with little energy.

Further, since nothing is provided in the flow path 3 such as a spiral plate as in the conventional case, a stable circulating flow can be generated.

Now, from the liquid inlet 9 to the liquid outlet 7
Is a cylindrical shape having a constant radius, but the liquid discharge port 7 connected to the flow path 3 has a divergent shape as shown in FIG.

As a result, the pressure of the liquid flowing through the flow path 3 in a high energy state is rapidly reduced, and a strong shearing force is generated, so that the bubbles contained in the liquid are separated by the shearing force. The contact area between the liquid and the bubbles expands explosively,
The dissolution of the blown gas (oxygen) is accelerated at once. Moreover, no external power is required to obtain this effect. As a result, with less energy,
In addition, oxygen can be dissolved in a liquid with high dissolution efficiency.

As described above, in the present invention, the generation of a stable circulation flow and the efficient dissolution of oxygen in a liquid are realized simultaneously with a small amount of energy. Therefore, the liquid can be effectively purified with a small amount of energy.

The generation of the circulating flow and the gas-liquid mixing (dissolution of oxygen in the liquid) both suppress the generation of blue-green algae,
It is indispensable for turbid water purification and large-scale wastewater treatment.

On the other hand, conventionally, a spiral plate is disposed in a pipe in order to give a swirling flow to the liquid, and this has caused a dust to be clogged in the suction port.

However, as described above, in the present invention, the pipe 1 is a straight straight pipe, and the flow path 3 has no obstacle. Then, the gas blowing hole 5 is set at an angle θ1 and the pipe 1
By simply opening the liquid in the tangential direction of the wall surface 11, a mechanism in which the liquid turns violently is realized. For this reason, unlike the related art, there is no clogging of the dust, and the dust is swirled together with the liquid and discharged from the liquid discharge port 7. As a result, labor for maintenance can be reduced as much as possible.

Next, the details of the gas blowing hole 5 will be described. As shown in FIG. 1, the gas blowing hole 5 is provided so as to be inclined at an angle θ1 with respect to the direction of travel of the liquid in the flow path 3 (the direction of the arrow a) in the vertical section of the pipe 1. The angle θ1 is set in a range from 10 degrees to 80 degrees. The swirling flow is the most intense in this range,
If the angle is smaller than 0 degree or larger than 80 degrees, the swirl flow is insufficient. Note that θ2
= 90−θ1.

The gas blowing hole 5 is formed in the horizontal section of the pipe 1 in the tangential direction of the wall surface 11 as shown in FIG. Thus, when formed in the tangential direction of the wall surface 11, the strongest swirling flow can be generated. Note that the gas blowing hole 5 needs to be opened so as to have at least a component in the tangential direction of the wall surface 11 in a horizontal cross section.

The number of the gas blowing holes 5 is about 3 to 8, but may be increased or decreased as needed.

The high-pressure gas blown from the gas blowing hole 5 formed as described above rises while turning as a bubble along the wall surface 11 of the pipe 1, and sucks the liquid from the liquid suction port 9. . The sucked liquid is mixed with the bubbles while swirling, rises, and reaches the liquid discharge port 7 provided so as to be divergent, at which a strong shear stress occurs, and the bubbles are turned into finer bubbles. You will be divided.

Here, the pressure of the high-pressure gas blown into the flow path 3 from the gas blowing hole 5 is approximately 0.1 to 10 kgf / c.
A range of square meters is appropriate. The high pressure gas is
A gas containing at least oxygen, such as air or oxygen, may be used.

Next, the details of the liquid discharge port 7 will be described. FIG. 3 is a vertical sectional view showing details of the liquid discharge port 7 of the pipe 1 of FIG. In FIG. 3, the same parts as those in FIG. 1 are denoted by the same reference numerals.

As shown in FIG. 3, the flow path 3 and the liquid discharge port 7
The angle λ formed by the tangent d contacting the curved surface of the liquid discharge port 7 at the connection point A with the liquid discharge port 7 is defined as the opening angle of the liquid discharge port 7. The opening angle λ of the liquid discharge port 7 is most preferably not less than 50 degrees and not more than 70 degrees. Otherwise, the opening angle λ is 3
0 degree or more is preferable. This is because if it is less than 30 degrees, the bubbles generated by the blown high-pressure gas cannot be miniaturized. Further, it is not preferable that the opening angle λ is larger than 90 degrees. Also in this case, the air bubbles cannot be made finer.

In the above description, the liquid discharge port 7 of the pipe 1 faces the liquid surface (the liquid suction port 9 of the pipe 1).
However, the pipe 1 was used upright in the liquid so that the pipe 1 faced the bottom side of the liquid. It is most preferable to install the pipe 1 in this manner, but if necessary, it can be used lying down (installed so that the length direction of the pipe 1 is parallel to the liquid surface). The liquid to be purified by the circulating flow generator of the present invention may be water or another liquid.

Next, the overall configuration of the circulating flow generator according to the embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a vertical sectional view of the circulating flow generator according to the embodiment of the present invention. As shown in FIG. 4, the circulating flow generator includes a pipe 1, a holder 15, a hose port 21.
And a compressor 23. The compressor 23 corresponds to a gas blowing unit.

Here, FIG. 5 is a view showing the pipe 1 shown in FIG. 4, and FIG. 6 is a view showing the holder 15 shown in FIG. 4 to 6, the same parts as those in FIG. 1 are denoted by the same reference numerals.

As shown in FIG. 5, in the pipe 1, the liquid discharge port 7 is formed such that the opening angle λ is 60 degrees. The gas blowing hole 5 has an angle θ in a vertical section.
1 is 60 degrees, and in a horizontal section,
It is formed in the tangential direction of the wall surface 11 (see FIG. 2).

Eight gas blowing holes 5 under such conditions are formed. A holder 15 is provided on the outer surface of the lower end of the pipe 1.
A male screw 13 is formed for connection with the screw. Note that this pipe 1 is different from the pipe 1 shown in FIG. 1 in the number of the gas blowing holes 5 and the point that the male screw 13 is formed.

As shown in FIG. 6, the holder 15 has a rectangular shape in a vertical section, and a cavity 25 is formed therein. And on the upper part of the holder 15,
An opening conforming to the outer shape of the pipe 1 is formed, and an internal thread 17 for connecting to the pipe 1 is formed in the opening.

A hole corresponding to the outer shape of the pipe 1 is formed in the lower inner surface of the holder 15, and a female screw 17 for connecting to the pipe 1 is formed around the hole. Furthermore, so that it penetrates from the hole to the outside of the holder 15,
A liquid inlet 19 is formed. A hose port 21 for blowing high-pressure air from the compressor 23 into the cavity 25 is provided on a side portion of the holder 15.

The female screw 1 of such a holder 15
7, the pipe 1 and the holder 15 are tightly connected by screwing the male screw 13 of the pipe 1 of FIG. 5 to assemble the circulating flow generator shown in FIG. In addition, it penetrates from the liquid suction port 19 to the liquid discharge port 7.

Next, the operation will be described with reference to FIG. The pipe 1 held by the holder 15 is erected underwater. A hose port 21 provided in the holder 15 is connected to a compressor 23 via a hose (not shown). Then, the high-pressure air generated by the compressor 23 is sent from the hose 21 to the cavity 25,
Through the flow path 3.

The high-pressure air blown becomes bubbles.
The water rises while turning the wall 11 of the pipe 1 while sucking water from the liquid suction ports 9 and 19. At this time, the water and the blown air are mixed.

Such a gas-liquid mixture of air and water generates a shear flow at the liquid discharge port 7 having an opening angle λ of 60 degrees,
Ultrafine bubbles will be generated.

The generated ultrafine bubbles make a swirling motion and spread while expanding their diameter, and the range of the spread of the bubbles is about several hundred thousand times the inner diameter of the pipe 1.

With the high-speed flow of the surface layer of water, the low-level water flows and rises to induce a circulation movement of the low-level → surface → low-level flow, thereby purifying the surface and lower-level water. .

A turbid water purification experiment of a dam was conducted using the above apparatus, and the results are shown below.

(Experiment 1) In Experiment 1, the length of the pipe 1 was 270 mm, and the outer diameter of the pipe 1 was 120 mm. Also, the inner diameter of the pipe 1 is 40 mm, the number of the gas blowing holes 5 is 8, the angle θ1 of the gas blowing holes 5 is 45 degrees, the opening angle λ of the liquid discharge port 7 is 60 degrees, the air pressure is 5 kgf / c square meter, The number of installations was one.

The results are as follows. Power consumption 3
In kw, in the range of water depth 33.5mx50 square meters,
The turbidity of 70 degrees before the start was restored to 2 degrees of turbidity (1 degree based on tap water turbidity) 168 hours after the start of operation. From the results of Experiment 1, it was confirmed that the surface temperature was also effective in suppressing the occurrence of water bloom, because 26 ° C. before the start decreased to 18 ° C. simultaneously with the start of the operation. In addition, it was confirmed that the present apparatus can purify a large amount of water with low power.

(Experiment 2) A purification experiment of a closed dam was performed. The water quality of the dam is as follows. The turbidity of the clay mineral is 70 degrees, the turbid water of the fine clay mineral remains in a large amount at a depth of 2 m to 30 m, and the lower part (water depth of 50 m or less) is anoxic. At the deepest part, elution of harmful methane gas and heavy metals was detected.

As a result of the operation of the present apparatus, the effect of destruction of underwater temperature stratification, the effect of purifying turbid water and blue-green algae, and the effect of increasing dissolved oxygen over a wide range (from 4.5 ppm to 6.5 ppm) were confirmed. By gradually lowering the apparatus, it was confirmed that it was possible to improve the anoxic zone at the deepest part to an aerobic zone, mineralize sludge, and prevent elution of heavy metals.

The present apparatus can be widely used in places where purification of liquids is required, such as lakes and marshes, closed sea areas, and large-scale wastewater treatment, in addition to dams.

[0066]

According to the present invention, the gas blowing hole is inclined at an acute angle with respect to the direction of travel of the liquid in the flow path.
And, it is provided so as to have a tangential component of the wall surface surrounding the flow path, and by blowing gas into the flow path through this gas blowing hole, a swirl flow is generated in the flow path, and generation of a circulating flow and And gas-liquid mixing at the same time.

As described above, instead of separately providing a mechanism for mixing a gas with a liquid and a mechanism for generating a circulating flow, a mechanism for mixing a gas with a liquid also has a mechanism for simultaneously generating a circulating flow. Has become. For this reason, gas-liquid mixing and generation of a circulating flow can be simultaneously realized with little energy. Further, since a member causing a trouble, such as a spiral plate, is not provided in the channel as in the related art, a stable circulating flow can be generated.

In addition to such an effect, by providing a liquid discharge port so as to spread out, a shear force can be applied.
Promotes dissolution of gas into liquid.

Therefore, in the present invention, the generation of a stable circulating flow and the efficient dissolution of oxygen in a liquid are simultaneously realized with little energy. Therefore, the liquid can be effectively purified with a small amount of energy.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a pipe constituting a circulating flow generator according to an embodiment of the present invention.

FIG. 2 is a horizontal sectional view of the pipe.

FIG. 3 is an explanatory view of a liquid discharge port of the pipe.

FIG. 4 is an overall configuration diagram of a circulating flow generator according to an embodiment of the present invention.

FIG. 5 is an explanatory view of the pipe of FIG. 4;

FIG. 6 is an explanatory view of the holder of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe 3 Flow path 5 Gas blow-in hole 7 Liquid discharge port 9, 19 Liquid suction port 11 Wall 13 Male screw 15 Holder 17 Female thread 21 Hose port 23 Compressor 25 Cavity

Continued on the front page F term (reference) 4D029 AA01 AB05 BB11 4G035 AA01 AB27 AC01 AE13

Claims (5)

[Claims] 1. A gas-liquid mixing means installed in a liquid for mixing a gas and a liquid, and a gas blowing means for blowing the gas into the gas-liquid mixing means, wherein the gas-liquid mixing means comprises: A flow path that is surrounded by a cylindrical wall surface and into which the gas is blown from the gas blowing means, a liquid discharge port provided at one end of the flow path, and a gas blowing hole for blowing the gas into the flow path. The liquid discharge port is provided so as to be divergent, and the gas blowing hole is, at a vertical cross section, obliquely inclined at an acute angle with respect to the traveling direction of the liquid in the flow path, and In a horizontal cross section, the circulating flow generator is provided so as to have a tangential component of a wall surrounding the flow path, and the gas contains at least oxygen. 2. An opening angle of the liquid discharge port is 50 degrees or more and 7 degrees or more.
2. The circulating flow generator according to claim 1, wherein the angle is 0 [deg.] Or less. 3. The gas blowing hole is provided so as to be inclined at an angle of 10 degrees or more and 80 degrees or less with respect to a traveling direction of the liquid in the flow path. A circulating flow generator as described. 4. The gas blowing hole is provided in a tangential direction of a wall surrounding the flow path.
The circulating flow generator according to any one of claims 1 to 3. 5. A gas inlet according to claim 1, wherein a plurality of said gas blowing holes are provided and are provided so as to blow said gas in a circulating direction along a wall surrounding said flow path. The circulating flow generator according to any one of the above.