JP2001276589A - Aerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aerator which can continuously supply air bubbles with a uniform bubble size of about several tens of μm to a liquid to be treated at a low energy consumption. SOLUTION: This aerator has a delivery stream formation vessel 3 which has a delivery port 4 opening at the bottom section 3a and is immersed in a liquid 1 to be treated; a gas-liquid mixing means 22 with which a gas-liquid mixture stream is formed since a gas is spontaneously sucked through a gas supply port by the flow of a liquid supplied under pressure to a liquid supply port; and a gas-liquid mixture stream supply means 7 which supplies under pressure the gas-liquid mixture stream from the gas-liquid mixing means 22 to the delivery stream formation vessel 3 in such a jetting direction that a flow revolving along the inner wall of the vessel 3 is formed. A gas-liquid two-phase stream formed by supplying under pressure the gas-liquid mixture stream to the vessel 3 is jetted and diffused through the delivery port 4 into the liquid 1 to be treated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aerator for generating fine bubbles in a liquid.

[0002]

2. Description of the Related Art As a method for purifying water from rivers, lakes and marshes, and purifying sewage such as domestic wastewater, there is known a method utilizing the biological oxidizing action of aerobic microorganisms in a liquid to be treated. Also, in the purification treatment by such a method, it is also known that it is effective to introduce fine air bubbles into the liquid to be treated in order to activate the biological oxidizing action of aerobic microorganisms.

[0003] Various types of bubble generators have been developed for such purification treatment. For example, in a method using a diffuser, the introduced gas is supplied as bubbles in the liquid through the pores. Further, in the mechanical method, the gas introduced by the rotating wings is fragmented to generate bubbles.

In the method using a diffuser, there is a variation in bubble size due to blockage of pores, a reduction in bubble generation rate, and a limit on the amount of bubble generation. In addition, because the stirring action is insufficient,
Although effective for a limited volume of processing solution, it has the drawback that it is impossible to process a large volume of solution for rivers and lakes. Further, the mechanical method has disadvantages in that the energy consumption is large and the variation in bubble size is large.

[0005] In a conventional bubble generator (hereinafter referred to as an aerator), for example, in the case of using a tube having pores arranged in a liquid tank to be treated, the bubble generator generates bubbles. There are problems that the bubble size varies and the bubble generation rate decreases, and that the amount of bubble generation is limited. In addition, there is a possibility that such blockage of the pores may occur in a relatively short time, and there is also a problem that maintenance of the aerator requires a large amount of labor.

In order to increase the degree of contribution to liquid purification, it is necessary that the generated bubbles and the liquid to be treated are well mixed. That is, the liquid containing the gas phase (gas-liquid mixed two-phase flow) discharged from the aerator is vigorously discharged into the liquid to be processed to generate bubbles, and the contact between the liquid to be processed and the bubbles is promoted by mixing. Is preferably performed.

Therefore, the present inventors have studied the above problems and have developed an aerator described in Japanese Patent Application Laid-Open No. 10-230150. With this aerator, it has become possible to increase the generation efficiency of bubbles in the liquid to be treated, and to increase the contact efficiency between the bubbles generated by the stirring action of the discharge flow and the liquid to be treated.

[0008]

As a result of a study conducted by the inventors of the present application, it was found that the bubble size was small between the bubble size of the bubbles supplied into the liquid to be treated by the gas-liquid mixed flow and the actual purification performance. It was recognized that the purification performance was improved as the size became uniform. In particular, when a large number of fine and uniform bubbles of about several tens of μm were generated, the purification performance was significantly improved.

That is, even if the total amount of air sent into the liquid is the same, if the bubble size is reduced, the surface area of the bubbles sent out into the liquid increases accordingly, and the contact area with the liquid increases. In addition, the floating time of the bubbles in the liquid becomes longer, and the contact time between the liquid and the bubbles becomes longer. Thereby, the dissolving efficiency of oxygen in the liquid is improved, and the contribution to the activation of the biological oxidizing action by the aerobic microorganisms is increased. Therefore, it is necessary to reduce the bubble size of the bubbles sent into the liquid to be treated for the purification process while reducing the bubble size in order to improve the purification performance.

The present invention has been made in view of such a problem, and it is possible to continuously supply a large amount of bubbles having a uniform size of about several tens μm into a liquid to be treated with a small amount of energy consumption. An object of the present invention is to provide an aerator that can be used.

[0011]

According to a first aspect of the present invention, a gas-liquid two-phase flow formed by taking a gaseous phase into a liquid is discharged into the liquid to be treated. In the aerator that supplies fine bubbles to the liquid to be processed, the discharge port is opened at the bottom and the discharge flow forming tank immersed in the liquid to be processed, and the flow of the liquid pressurized and supplied to the liquid supply port is used. A gas-liquid mixing unit that forms a gas-liquid mixed flow in which the gas is mixed into the liquid by the natural suction of the gas from the gas supply port, and the gas-liquid mixed flow from the gas-liquid mixing unit, Gas-liquid mixed flow supply means for pressurizing and supplying the discharge flow forming tank with a jetting direction of a swirling flow swirling inside the tank along the peripheral wall of the discharge flow forming tank, The gas-liquid two-phase flow formed by pressurizing the flow is expanded from the discharge port into the liquid to be treated. Characterized by injection.

In this aerator, the gas is spontaneously sucked from the gas supply port by the liquid supplied to the liquid supply port of the gas-liquid mixed flow supply means to form a gas-liquid mixed flow in which the gas is introduced into the liquid. . The swirling flow along the peripheral wall of the discharge flow forming tank obtained by injecting and supplying this gas-liquid mixed flow into the discharge flow forming tank flows toward the discharge port while turning in the tank. Part of the gas contained in the gas-liquid mixed flow is dissolved in the liquid, and the remaining gas is pressed against the center of the discharge flow forming tank by the buoyancy of the gas itself to form an air core. Thus, in the discharge flow forming tank, a gas-liquid two-phase flow is formed by the swirling flow of the liquid and the air core. When the gas-liquid two-phase flow is diffused and ejected from the discharge port of the discharge flow forming tank, a gas mass is formed near the discharge port, and the gas mass is subdivided by a large shear force. In addition, a part of the gas introduced into the discharge flow forming tank from the gas-liquid mixing means dissolves in the liquid, and when the gas is diffused and injected into the liquid to be treated from the discharge port of the discharge flow forming tank, the pressure is reduced. Accordingly, the dissolved gas precipitates in the liquid to generate fine bubbles. Thereby, a large amount of substantially uniform and fine bubbles can be stably supplied into the liquid to be treated.

According to a second aspect of the present invention, the aerator is provided with a control valve for adjusting an amount of gas supplied to the gas supply port.

In this aerator, the amount of gas introduced into the discharge flow forming tank by the suction action of the liquid flow is adjusted by the control valve, so that the amount of air inflow can be appropriately adjusted according to the use environment. As a result, the bubble size can be reliably reduced.

According to a third aspect of the present invention, in the aerator, the discharge flow forming tank has a circular cross section perpendicular to the swirling center axis of the swirling flow, and the gas-liquid mixed flow supply means is connected to the discharge flow forming tank. It is characterized by being connected tangentially to the inner peripheral surface.

In this aerator, the swirling flow is smoothly formed along the inner peripheral surface of the discharge flow forming tank by supplying the liquid from the gas-liquid mixed flow supplying means.

According to a fourth aspect of the present invention, the bottom of the discharge flow forming tank is formed in a conical shape protruding in the direction of jetting the gas-liquid two-phase flow.

In this aerator, by forming the bottom of the discharge flow forming tank into a conical shape, the flow of the swirling flow generated in the discharge flow forming tank can be made smooth, and the pressure loss can be reduced.
For this reason, it is possible to achieve a configuration that consumes less power and has high energy efficiency.

According to a fifth aspect of the present invention, the bottom of the discharge flow forming tank is formed in a flat plate shape.

In this aerator, the discharge flow forming tank can be formed in a simple shape, the production cost can be reduced, and the size of the aerator can be reduced.

According to a sixth aspect of the present invention, in the aerator of the present invention, the gas-liquid mixed flow supply means is connected to a wall of the discharge flow forming tank located at a predetermined height from the bottom of the discharge flow forming tank.

In this aerator, the bias of the swirling flow is reduced by supplying the gas-liquid mixed flow from a position at a predetermined height from the bottom in the discharge flow forming tank and continuing the swirling between the predetermined heights. In addition, it is possible to uniformly diffuse and inject from the discharge port.

According to a seventh aspect of the present invention, in the aerator, the gas is naturally sucked by the swirling flow from a gas introduction port provided in the discharge flow forming tank so as to face the discharge port, so that the gas flows into the discharge flow forming tank. It is characterized by comprising gas supply means for supplying.

In this aerator, by supplying gas from the gas supply means in addition to the gas introduced from the gas-liquid mixing means, the gas supply amount of the entire apparatus is increased, and the gas-liquid mixing rate is reduced. Can be improved.

An aerator according to claim 8 is characterized in that a nozzle for stabilizing the introduction of gas is provided at a gas introduction port of the gas supply means.

In this aerator, the flow of gas newly introduced toward the discharge port of the discharge flow forming tank is stabilized, and the flow of the formed gas-liquid two-phase flow in the liquid to be treated is stabilized. . Thereby, the shear stress at the interface between the gas-liquid mixed two-phase flow diffused and injected from the discharge flow forming tank and the liquid to be treated outside the discharge flow forming tank can be stabilized.

According to a ninth aspect of the present invention, in the aerator of the present invention, a plurality of the gas-liquid mixed flow supply means are connected to different positions of the discharge flow forming tank in a tangential direction with respect to an inner peripheral surface of the discharge flow forming tank. And

In this aerator, by connecting a plurality of gas-liquid mixed flow supply means to the discharge flow forming tank, the supply amount of gas increases, and the swirling flow in the discharge flow forming tank becomes a stronger flow. Thereby, the chance of contact between the gas and the liquid increases, and the efficiency of dissolving the gas in the liquid improves.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a view showing an embodiment of an aerator according to the present invention, FIG. 2 is a configuration diagram of an aerator of the present embodiment, (a) is a longitudinal sectional view, and (b) is A in FIG. 2 (a). FIG.
The aerator 100 of the present embodiment is used in a state where it is immersed in a processing tank 2 in which a liquid 1 to be treated is stored as shown in FIG. 1 and has a uniform size of about several tens μm in the liquid 1 to be treated. It is characterized by supplying a large amount of fine bubbles stably.

As shown in FIGS. 1 and 2, the aerator 100 of the present embodiment has a cylindrical peripheral wall and a bottom portion 3a formed in a conical shape projecting outward, and the conical bottom portion 3a. The liquid is supplied under pressure to the liquid supply port and the liquid is supplied to the liquid supply port under pressure and the gas is naturally sucked from the gas supply port by the flow of the liquid, so that the gas flows into the liquid. Has an aspirator 22 as gas-liquid mixing means for forming a gas-liquid mixed flow in which the gas-liquid mixed flow is mixed. The gas-liquid mixed flow from the aspirator 22 is passed through the pipe 5 along the peripheral wall of the discharge flow forming tank 3 in the tank. And a gas-liquid mixed flow supply means 7 for pressurizing and supplying the discharge flow forming tank 3 with a jetting direction of a swirling flow. The processing tank 2 includes an aerator 1
The capacity is set in accordance with the processing performance by 00, and as the required processing amount increases or decreases, a processing capacity or number of aerators corresponding to the increase or decrease are appropriately used. Alternatively, a processing tank having a volume corresponding to the processing performance of the aerator is appropriately selected.

The gas-liquid mixed flow supply means 7 includes the discharge flow forming tank 3
The outlet side of the aspirator 22 is connected to the pipe line 5 communicating with the aspirator 22, the gas supply pipe on the inlet side of the aspirator 22 is connected to the gas introduction pipe 24, and the liquid supply port is connected to a pump (not shown) to pressurize the liquid W. It is configured by connecting a liquid supply pipe 26 to be supplied. The gas-liquid mixed flow supply means 7 introduces gas by natural suction from the gas introduction pipe 24 into the liquid supplied under pressure from the liquid supply pipe 26, and jets and supplies the gas-liquid mixed flow to the discharge flow forming tank 3. . In the present embodiment, the liquid W supplied to the discharge flow forming tank 3 by the gas-liquid mixed flow supply means 7 is the same as the liquid 1 to be processed stored in the processing tank 2.
The liquid is not limited to this, and may be another liquid.

The connection angle of the pipe 5 to the discharge flow forming tank 3 defines the direction in which the liquid W to be fed to the discharge flow forming tank 3 is jetted. Is set so as to form a swirling flow that swirls in the tank along. That is, in the present embodiment, as shown in FIG. 2B, the pipe 5 is connected to the inner peripheral surface of the discharge flow forming tank 3 in a tangential direction. The pipe 5 is connected to the wall of the discharge flow forming tank 3 at a position separated from the bottom of the discharge flow forming tank 3 by a predetermined height, here, at a position close to the height H of the aerator, so that the pipe 5 The supplied liquid continues to swirl in the discharge flow forming tank 3. Thereby, the bias of the swirling flow is eliminated, and the jet is uniformly diffused from the discharge port.

The bottom 3a of the discharge flow forming tank 3 is shown in FIG.
As shown in (1), it is formed in a conical shape protruding outward in the ejection direction from the discharge port 4 so that the swirling flow smoothly goes to the discharge port 4.

Next, the operation of the aerator 100 will be described. As shown in FIG. 1, the aerator 100 having the above-described structure is swirled into the discharge flow forming tank 3 by pressurizing and supplying the liquid W containing the gas G to the discharge flow forming tank 3 by the gas-liquid mixed flow supplying means 7. A flow is formed. The swirling flow is generated in the discharge flow forming tank 3
After turning on the inner peripheral surface of the nozzle, the flow comes out of the discharge port 4. A part of the gas contained in the gas-liquid mixed flow is dissolved in the liquid, and the remaining gas is pressed against the center of the discharge flow forming tank 3 by the buoyancy of the bubble itself as conceptually shown in FIG. An air core 11 is formed. Thus, the discharge flow forming tank 3
Inside, a gas-liquid two-phase flow is formed by the swirling flow of the liquid in which the gas is dissolved and the air core.

Then, the gas-liquid two-phase flow in the formed discharge flow forming tank 3 is diffused and jetted from the discharge port 4 into the liquid 1 to be treated. At this time, as shown in FIG. 1, an air pocket 12, which is a lump of air injected from the nozzle 10, is formed in the vicinity of the discharge port 4, and is finely formed by a shearing action at a boundary between the air pocket and the liquid 1 to be processed. Bubbles are generated. Further, the gas dissolved in the liquid becomes fine bubbles at the same time as the pressure is released at the discharge port. Then, at a certain distance from the discharge port 4, a gas-liquid mixed flow 16 in which the microbubbles 14 are mixed almost uniformly is formed.

In such an aerator 100,
The gas-liquid interfacial tension in the gas-liquid mixed two-phase flow discharged from the discharge port 4 of the discharge flow forming tank 3 is σ _{w / g} , and the gas-liquid mixed two-phase flow and the liquid 1 to be treated outside the discharge flow forming tank 3 are different from each other. Assuming that the shear stress at the interface 18 between S and S is S, and the diameter of the bubble generated in the gas-liquid mixed flow 16 is d _a , the following equation is established. d _a = 4 (σ _{w / g} ) / S

That is, as the shear stress S increases and the gas-liquid interfacial tension σ _{w / g} decreases, the gas-liquid mixed two-phase flow is discharged from the discharge port 4 of the discharge flow forming tank 3. The bubble size in the mixed gas-liquid flow is reduced, and the variation in bubble size is suppressed. Further, the mixing ratio of bubbles in the generated gas-liquid mixed flow 16 is also increased. Therefore, in order to obtain a large amount of small-sized bubbles, the shear stress S at the interface 18 between the gas-liquid mixed two-phase flow and the liquid 1 to be treated is increased, and the interfacial tension σ _{w / g} of the gas-liquid is reduced. It becomes important. According to the aerator of the present embodiment, the air jetted from the discharge port 4 is forcibly passed through the interface having a large shear stress, thereby achieving the miniaturization of the bubble size and the reduction of the variation in the bubble size. ing.

Hereinafter, the effects of the aerator 100 will be described in detail. According to the configuration of the aerator 100, the gas introduced into the aspirator 22 is turned into bubbles in the liquid and swirls in the discharge flow forming tank 3, thereby increasing the chance of contact with the liquid at a high pressure. In the liquid is promoted. Further, the gas introduced from the gas-liquid mixed flow supply means 7 stays at a position where the discharge force from the discharge port 4 and the buoyancy of the gas itself are balanced, surrounded by the interface 18 having a large shear stress, and accumulates in the air pool. 12 is formed. Since the gas in the air pool 12 passes through the interface 18 having a large shear stress and is dispersed in the liquid to be treated, the air generated by the contact between the introduced gas and the interface 18 causes the air pool 1
The gas in 2 is divided efficiently and finely.

Since the gas is introduced into the liquid at an increased pressure and the chance of contact between the gas and the liquid is increased, the dissolution of the gas into the liquid is promoted. For this reason, when the gas-liquid two-phase flow is diffused and injected from the discharge port 4 of the discharge flow forming tank 3, the decompression action promotes the deposition (bubbling) of the dissolved gas in the liquid.

Further, the swirling force of the gas-liquid mixed flow supplied into the discharge flow forming tank 3 by the gas-liquid mixed flow supply means 7 presses the gas flow toward the center of swirling and is discharged from the discharge flow forming tank 3. It also plays a role of accelerating the deposition and atomization of gas by the depressurizing action at the time, and also has an action of increasing the mixing ratio of bubbles in the gas-liquid mixed flow 16.

By forming the bottom 3a of the discharge flow forming tank 3 in a conical shape, the flow of the swirling flow generated in the discharge flow forming tank becomes smooth, and the pressure loss is reduced. For this reason,
An aerator with a low energy requirement and high energy efficiency can be provided. Further, the axial flow velocity distribution of the liquid in the vicinity of the discharge port 4 becomes gentle and stable.

As described above, the aerator 10 of the present embodiment is
In the case of 0, the above effects act synergistically, so that it is possible to stably supply a large amount of fine bubbles having a diameter of about several tens of μm at a constant size. Further, the energy for flowing the liquid and the gas and dispersing the bubbles is small, so that the energy consumption of the entire apparatus can be reduced and the noise can be reduced. Then, in order to supply the liquid under pressure, the stirring action of the liquid is improved, the relative speed between the liquid and the bubbles is increased, the renewal speed of the surface coating of the bubbles is increased, and oxygen is introduced into the liquid to be treated. The moving speed can be improved.

If this aerator 100 is used for purification processing, excellent purification performance can be obtained, and at the same time, the size and cost of the purification device can be reduced. The aerator 100 can also be operated by combining a plurality of discharge flow forming tanks 3 each having a gas inlet 8a, and branching and connecting a single gas-liquid mixed flow supply means 7. Therefore, it can be easily adapted to large-capacity processing such as purification of rivers and lakes.

In order to increase the reliability of miniaturizing and stabilizing the bubble size, it is preferable to set the dimensions and conditions of each part of the apparatus as follows. V ₂ = 20 to 200 m / sec d ₀ /D=0.05 to 0.5 θ = 30 ° to 180 ° where V ₂ is the flow rate of the gas-liquid two-phase flow discharged from the discharge port 4, and D is the inner diameter of the discharge flow forming tank 3, d ₀ is the inner diameter of the discharge port 4, theta is the apex angle of the bottom 3a.

Further, the shape of the discharge flow forming tank 3 is not limited to the cylindrical shape or the combination of the cylinder and the cone in the present embodiment, but the gas-liquid supplied by the gas-liquid mixed flow supply means is formed along the peripheral wall. For example, the shape may be an ellipsoid or a spherical shape as long as the shape forms a swirling flow swirling in the tank. That is, the shape of the discharge flow forming tank 3 may be any shape as long as the cross section orthogonal to the center axis of the swirling flow is formed in a circular shape. In addition, a control valve (not shown) for adjusting the air flow rate is provided in the middle of the gas introduction pipe 24 connected to the aspirator 22, and by adjusting the amount of air introduced into the aspirator 22, the shape and operating conditions of the aerator can be changed. On the other hand, the bubble size can be kept fine and constant, and the operating conditions can be adjusted according to the use environment so that the aerator can always be operated in an optimal state.

Next, a modified example of the aerator of this embodiment will be described. FIG. 4 is a longitudinal sectional view showing the configuration of the aerator of the present modification. This aerator 200 is also used in a state of being immersed in the processing tank 2 in which the liquid 1 to be treated is stored as in FIG. 1, and fine bubbles of a uniform size having a diameter of about several tens μm are formed in the liquid 1 to be treated. Stable mass supply. Note that members having the same functions as in FIG. 2 are given the same reference numerals, and description thereof is omitted here.

The aerator 200 of this modified example has a discharge flow forming tank 20 having a discharge port 4 opened at the center of a bottomed cylindrical bottom 20a, and the discharge flow forming tank 20 has a flat bottom 20a. Is formed. According to this configuration, the discharge flow forming tank 20 can be formed into a simple shape that can be easily processed, the manufacturing cost can be reduced, and the size of the aerator can be reduced because there is no protrusion.

Next, a second embodiment of the aerator according to the present invention will be described. FIG. 5 shows an aerator 300 of the present embodiment.
A cross-sectional view of FIG. As shown in FIG. 5, an aerator 300 of the present embodiment has a configuration in which another gas supply unit is provided in addition to the configuration of the aerator 100 of the first embodiment.

The gas supply means 9 has a gas inlet 8a disposed so as to face the discharge port 4 of the discharge flow forming tank 3, and supplies air into the tank. The gas inlet 8a is arranged by extending one end of the conduit 8 into the tank so as to be immersed in the liquid in the tank, and a nozzle 10 for stabilizing the introduction of air is provided at the tip thereof. I have. The other end of the pipe 8 is open to the atmosphere, and air at atmospheric pressure is introduced into the discharge flow forming tank 3 by natural suction. Although not shown, it is preferable to provide a control valve for adjusting the air introduction amount in the middle of the pipe 8. Further, in order to simplify the configuration, the gas inlet 8a is provided facing the discharge port 4 at the center of the tank end face opposite to the bottom 3a of the discharge flow forming tank without extending the pipe 8 into the tank. May be adopted.

Further, by providing the nozzle 10 at the gas inlet 8a of the gas supply means 9, the state of introduction of the gas introduced from the inside of the discharge flow forming tank 3 toward the discharge port 4 is stabilized. The discharge speed of the gas-liquid mixed two-phase flow discharged from the discharge port 4 of the discharge flow forming tank 3 can be stabilized. Thus, it is possible to stabilize the shear stress S at the interface 18 between the gas-liquid mixed two-phase flow diffused and injected from the discharge port 4 of the discharge flow forming tank 3 and the liquid 1 to be treated outside the discharge flow forming tank 3. it can.

The shear stress at the interface 18 between the gas-liquid mixed two-phase flow discharged from the aerator 300 and the liquid 1 to be treated outside the discharge flow forming tank 3 is compared between the case where the nozzle 10 is mounted and the case where the nozzle 10 is not mounted. The difference in the stability of S is remarkable, and it is possible to discharge a large amount of fine bubbles stably in a large amount when attached. Further, by stabilizing the shear stress S in a large state, the mixing ratio of the fine bubbles 14 in the gas-liquid mixed flow 16 can be increased. Further, since the bottom 3a of the discharge flow forming tank 3 is formed in a conical shape, the axial flow velocity distribution of the liquid in the vicinity of the gas inlet nozzle becomes gentle, and the suction force is large and stable. Thus, the amount of gas introduced can be increased. In order to increase the reliability of miniaturization and constant bubble size,
It is preferable to set the dimensions and conditions of each part of the apparatus as follows. d ₁ / d ₀ = 0.1 to 1 h / H = 0 to ₁ V ₁ = 0.1 to 100 m / sec where d ₁ is the inner diameter of the nozzle 10, h is the height of the nozzle 10 in the tank, H Is the height of the discharge flow forming tank 3, V ₁ is the nozzle 10
It is the flow velocity of the air injected from.

Next, a third embodiment of the aerator according to the present invention will be described. FIG. 6 is a sectional view of the aerator of the present embodiment. As shown in FIG. 6, a plurality of gas-liquid mixed flow supply means are equally arranged in the circumferential direction of the peripheral wall surface of the discharge flow forming tank 3 with respect to the discharge flow forming tank 3 of the aerator 400. It is connected tangentially to the peripheral surface. In the case of the present embodiment, two gas-liquid mixed flow supply means are provided, and the gas-liquid mixed flow supply means 7 connected to the discharge flow forming tank 3 is provided.
The second gas-liquid mixed flow supply means 13 is connected to the peripheral wall surface facing the connection position of the above. The pipe 28 of the second gas-liquid mixed flow supply means 13 may be a branch of the pipe 5 of the gas-liquid mixed flow supply means 7. May be supplied.

According to the structure of this embodiment, the swirling flow generated in the discharge flow forming tank 3 can be made stronger and more stable, and accordingly, the chance of contact between the gas and the liquid can be increased. To promote the dissolution of the gas into the liquid. In addition, the installation position of the conduit 28 is not limited to the position facing the conduit 5 and may be any position on the inner peripheral surface of the discharge flow forming tank 3. Further, a configuration in which a plurality of conduits are provided. Good.

[0054]

According to the aerator of the present invention, the swirl flow is formed by pressurizing and supplying the gas-liquid mixed flow formed by the gas-liquid mixed flow supply means into the discharge flow forming tank. The gas is suctioned from the gas supply means and introduced into the discharge flow forming tank by natural suction. On the other hand, the bubbles contained in the gas-liquid mixed flow are pressed against the center of the discharge flow forming tank by the buoyancy of the bubbles themselves, and form an air core together with the air introduced from the gas supply means. In this way, a gas-liquid two-phase flow is formed in the discharge flow forming tank by the swirling flow of the liquid and the air core, and the gas-liquid two-phase flow is diffused and injected from the discharge port of the discharge flow forming tank. This makes it possible to continuously supply a large amount of fine and uniform bubbles in the liquid to be treated with low energy consumption. By using this aerator for purification processing, excellent purification performance can be obtained, and the size and cost of the purification device can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration example of a first embodiment of an aerator according to the present invention.

2A and 2B are diagrams showing a configuration of an aerator, wherein FIG. 2A is a longitudinal sectional view, and FIG. 2B is a sectional view taken along the line AA in FIG. 2A.

FIG. 3 is an explanatory view conceptually explaining the operation of the aerator according to the present invention.

FIG. 4 is a longitudinal sectional view showing a configuration of a modified example of the aerator according to the present invention.

FIG. 5 is a diagram showing a configuration example of a second embodiment of an aerator according to the present invention.

FIG. 6 is a diagram showing a configuration example in a third embodiment of the aerator according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 liquid to be processed 2 processing tank 3, 20 discharge flow forming tank 3a, 20a bottom 4 discharge port 7, 13 gas-liquid mixed flow supply means 8a gas introduction port 9 gas supply means 10 nozzle 14 bubble 16 gas-liquid mixed flow 22 aspirator ( Gas-liquid mixing means) 100, 200, 300, 400 Aerator G Air W Liquid

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshio Yoshimi 8-1 Hirai Hinodemachi, Nishitama-gun, Tokyo Nippon Steel Mining Co., Ltd. (72) Inventor Michio Nonaka 1-31-20F Shimotakaido, Suginami-ku, Tokyo Terms (reference) 4D029 AA09 AB03 BB11 CC07 4G035 AB15 AB16 AC15 AC24 AE02 AE13 4G037 AA02 EA01

Claims (9)

[Claims] 1. An aerator that supplies fine gas bubbles to a liquid to be processed by discharging a gas-liquid two-phase flow formed by taking a gas phase into a liquid into the liquid to be processed. And a gas-liquid mixture in which the gas is naturally sucked from the gas supply port by the flow of the liquid pressurized and supplied to the liquid supply port. A gas-liquid mixing unit that forms a mixed flow, and discharges the gas-liquid mixed flow from the gas-liquid mixing unit in a jet direction that forms a swirling flow that swirls inside the tank along the peripheral wall of the discharge flow forming tank. A gas-liquid mixed flow supply means for pressurizing and supplying a gas-liquid mixed flow to the flow forming tank, and forming a gas-liquid two-phase flow formed by pressurizing and supplying the gas-liquid mixed flow to the discharge flow forming tank from the discharge port into the liquid to be treated. An aerator characterized in that it is diffused and jetted. 2. The aerator according to claim 1, further comprising a control valve for adjusting an amount of gas supplied to the gas supply port. 3. The discharge flow forming tank has a circular cross section orthogonal to a swirling center axis of the swirling flow, and the gas-liquid mixed flow supply means is provided with respect to an inner peripheral surface of the discharge flow forming tank. 3. A tangential connection.
Aerator as described. 4. The discharge flow forming tank according to claim 1, wherein a bottom portion of the discharge flow forming tank is formed in a conical shape protruding in a jet direction of the gas-liquid two-phase flow. Aerator. 5. The discharge flow forming tank according to claim 1, wherein a bottom portion of the discharge flow forming tank is formed in a flat plate shape.
The aerator according to the item. 6. The discharge flow forming tank according to claim 1, wherein the gas-liquid mixed flow supply means is connected to a wall of the discharge flow forming tank located at a predetermined height from a bottom of the discharge flow forming tank. An aerator according to any one of the preceding claims. 7. A gas supply means for supplying a gas to the discharge flow forming tank by causing the gas to be naturally sucked by the swirling flow from a gas introduction port provided in the discharge flow forming tank so as to face the discharge port. The aerator according to any one of claims 1 to 6, further comprising: 8. The aerator according to claim 7, wherein a nozzle for stabilizing gas introduction is provided at a gas introduction port of said gas supply means. 9. The discharge flow forming tank, wherein a plurality of the gas-liquid mixed flow supply means are tangentially connected to an inner peripheral surface of the discharge flow forming tank at different positions.
The aerator according to claim 8.