JPH1033961A - Gas-liquid mixer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen the cost of a liquid-gas mixer and make the apparatus compact and light. SOLUTION: A single step regenerator pump 43 comprises a casing 44 having a water sucking suction inlet 52 and a discharging outlet 53 to discharge the water sucked through the suction inlet 52, an impeller 47 installed in the casing 44 and having a large number of vanes 48b in the circumferential part of a circular disk 47a, and a flow route 48 formed in the casing 44 to lead the water sucked through the inlet 52 to the discharging outlet 53. The surface area in the direction vertical to the water flowing direction in the flow route 48 becomes smaller from the inlet 52 side to the outlet 53 side. In this case, a gas introducing means 34 to send air to pressured water is installed in the middle of the flow route 48 in which the pressure of water is gradually increased from the inlet 52 side to the outlet 53 side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-liquid mixing apparatus for dissolving and dispersing a gas in a liquid under high pressure to produce a liquid which generates a large number of fine bubbles at a low pressure.

[0002]

2. Description of the Related Art FIG. 14 shows a conventional gas-liquid mixing apparatus. In FIG. 14, reference numeral 12 denotes a high-lift pump, and reference numeral 13 denotes an injector. This injector 1
3 is a nozzle 14 and this nozzle 14 as shown in FIG.
And an air intake 16 is formed in the peripheral wall of the air outlet 15.
When water is supplied from an inlet 17 of the nozzle 14, the water is ejected from an outlet 20 through a nozzle hole 18 and a blowing hole 19. When the water passes through the room 21 formed at the entrance of the blowing unit 15, air at atmospheric pressure can be drawn in from the air intake 16 and entrained, whereby the water entrained by the air can be discharged. Exit 20
Can squirt from.

According to this gas-liquid mixing device, when the vortex pump 12 is driven, water 28 passes through the suction pipe 22 and branches off at the outlet of the suction pipe 22.
3 flows into the suction port 24 of the centrifugal pump 12, and the other flows into the suction port 24 through a communication pipe 25 provided with the injector 13. Therefore, the water mixed with air flows into the pump 12, and the pump 12 can dissolve and disperse the air into the water by stirring the water mixed with the air by the rotation of the impeller (impeller). The pressure in the pump 12 is increased by the rotation of the impeller. Then, water obtained by dissolving the air is discharged from the discharge port 26. The water discharged from the discharge port 26 generates bubbles 30 under the atmospheric pressure.

This gas-liquid mixing apparatus is used, for example, in a flotation method in a wastewater treatment process. With the flotation separation method, water containing air bubbles is mixed into sewage containing suspended solids with poor sedimentation properties, and when air bubbles float in the sewage, the air bubbles adhere to the suspended solids to reduce the specific gravity of the suspended solids. In this method, the suspended matter having a small specific gravity is floated on a sewage surface and separated therefrom.

However, in the gas-liquid mixing device shown in FIG.
Since the pressure in the suction port 24 is a low pressure equal to or lower than the atmospheric pressure due to the suction force of the pump 12, the volume of the air sent from the injector 13 to the suction port 24 is relatively large. As a result, the vehicle idles, and the ability of the pump 12 to push out water is reduced. Therefore, there is a problem that the water pressure in the pump 12 cannot be increased to a high pressure. As described above, when the pressure in the pump 12 does not become high, that is, when the pressure is low, the amount of air that can be dissolved in water decreases, and therefore, the air discharged from the discharge port 26 of the pump 12 is discharged. Water has the problem that only small amounts of bubbles can be generated under atmospheric pressure. On the other hand, if the amount of air sent from the injector 13 to the suction port 24 is reduced so that the impeller does not run idle, the amount of air that can be dissolved in water decreases, so that the water discharged from the discharge port 26 There is a problem that only a small amount of bubbles can be generated under atmospheric pressure. As described above, according to the conventional gas-liquid mixing apparatus shown in FIG. 14, for example, in a wastewater treatment step, the chance of attaching air bubbles to the floating substance is reduced, and the amount of the floating substance that can float on the sewage surface is reduced. There is a problem.

In order to solve the above problem, the applicant of the present invention has proposed a gas-liquid mixing apparatus shown in FIG. 15 (Japanese Patent No. 251617).
No. 2, Japanese Patent Application No. 259192). 15, 31 is a first pump, 32 is a second pump, and 13 is an injector. When the gas-liquid mixing device drives the first pump 31 and the second pump 32, the first pump 31 sucks water from the first suction port 35 and discharges water from the first discharge port 37, The second pump 32 sucks water discharged from the first discharge port 37 from the second suction port 38 and discharges the water from the second discharge port 42. The water discharged from the second discharge port 42 is depressurized by the decompression device 33 and sent out. Thereby, the first discharge port 37 and the second discharge port 4
The pressure of the water in the communication pipe 40 between the two
1, it can be raised by the second pump 32. Then, the injector 13 is connected to the second suction port 38.
Air can be caused to flow into the second pump 32. As a result, the second pump 32 can stir the water into which the air is mixed with the impeller under a predetermined high pressure, so that the air can be efficiently dissolved and dispersed in the water.

Thus, according to the device shown in FIG.
The pressure in the second pump 32 that stirs the water mixed with air can be increased mainly by the first pump 31, thereby being higher than the pressure in the pump 12 shown in FIG. . Therefore, the amount (weight) of air dissolved and dispersed in water can be increased as compared with the apparatus shown in FIG. Thereby, water containing a large amount of fine bubbles 30 can be discharged. In addition, 28 shown in FIG. 15 is fresh water, and 29 is sewage containing suspended substances.

[0008]

However, the conventional gas-liquid mixing device shown in FIG. 15 requires the first pump 31 for increasing the pressure in the second pump 32, and accordingly, There is a problem that the cost is high and the bulk of the device is large.

An object of the present invention is to reduce the cost of the apparatus and to provide a small and light gas-liquid mixing apparatus.

[0010]

A gas-liquid mixing apparatus according to a first aspect of the present invention is provided with a casing having a suction port for sucking a liquid, a discharge port for discharging the liquid sucked from the suction port, and a casing provided in the casing. And a flow path for guiding the liquid sucked from the suction port to the discharge port, and an area in a direction perpendicular to the direction of flow of the liquid in the flow path is defined by the discharge port side from the suction port side. In a one-stage pump that becomes narrower toward the outlet side, a gas that feeds gas into the pressured liquid from the middle of the flow path in which the pressure of the liquid is gradually increased from the suction port side toward the discharge port side The inflow means is provided.

According to a second aspect of the present invention, there is provided a gas-liquid mixing apparatus comprising: a casing having a suction port for sucking a liquid; and a discharge port for discharging the liquid sucked from the suction port; an impeller provided in the casing; A single-stage pump provided with a flow path for guiding liquid sucked from the suction port to the discharge port, wherein the area in the direction perpendicular to the direction in which the liquid flows in the flow path provided in the middle of the flow path is narrow. And a gas inflow means for feeding gas into the pressurized liquid in the flow path on the suction port side of the narrowed portion.

A gas-liquid mixing device according to a third aspect of the present invention provides a casing having a suction port for sucking a liquid, a discharge port for discharging the liquid sucked from the suction port, and a casing provided in the casing and provided on an outer peripheral portion of a disk. An impeller formed with a number of blades, and a flow path formed in the casing along the outer periphery of the impeller and guiding liquid sucked from the suction port to the discharge port, the liquid in the flow path In a single-stage regenerating pump, the area in the direction perpendicular to the flowing direction of the pump becomes narrower from the suction port side toward the discharge port side.
A gas inflow means for feeding gas into the pressured liquid from the middle of the flow path in which the pressure of the liquid is sequentially increased from the suction port side toward the discharge port side is provided.

According to a fourth aspect of the present invention, there is provided a gas-liquid mixing apparatus, comprising: a casing; an impeller provided in the casing; and a suction port provided in the casing and adapted to guide the sucked liquid to a center portion of the impeller. A discharge port provided in the casing for discharging liquid sucked from the suction port, and a flow path formed from a center portion of the impeller to an outer peripheral portion and guiding the liquid sucked from the suction port to the discharge port. A single-stage centrifugal pump in which the area in the direction perpendicular to the direction in which the liquid flows in the flow path decreases from the center to the outer periphery of the impeller. A gas inflow means for feeding gas into the pressurized liquid from the middle of the flow path in which the pressure of the liquid is sequentially increased from the center toward the outer periphery is provided.

According to a fifth aspect of the present invention, there is provided a gas-liquid mixing apparatus comprising: a casing; an impeller provided in the casing; and a suction port provided in the casing and adapted to guide the sucked liquid to the center of the impeller. A discharge port provided in the casing for discharging liquid sucked from the suction port, and a flow path formed from a center portion of the impeller to an outer peripheral portion and guiding the liquid sucked from the suction port to the discharge port. , A ring-shaped partition means formed on the inner surface of the casing in a non-contact state with the impeller, and surrounding a center portion of the impeller; and a center of the partition means and the center of the impeller. And a gas inflow means for feeding gas into the pressure liquid in the flow path between the first and second parts.

According to a sixth aspect of the invention, there is provided a gas-liquid mixing apparatus according to the fifth aspect, wherein a plurality of the annular partitioning means are provided.

According to a seventh aspect of the present invention, in the first, second, third, fourth, fifth, or sixth aspect, the gas-liquid mixing device sends the liquid discharged from the discharge port under reduced pressure. A pressure reducing device is provided at the discharge port.

According to an eighth aspect of the present invention, there is provided a gas-liquid mixing apparatus, comprising: a casing; an impeller provided in the casing; and a suction port provided in the casing and adapted to guide the sucked liquid to a center portion of the impeller. A discharge port provided in the casing for discharging liquid sucked from the suction port, and a flow path formed from a center portion of the impeller to an outer peripheral portion and guiding the liquid sucked from the suction port to the discharge port. A one-stage centrifugal pump comprising: a side surface formed on a side opposite to a side surface on which the flow path of the impeller is formed;
Gas inlet means for feeding gas into a gap formed between the inner wall surface of the casing facing the side surface is provided.

According to a ninth aspect of the present invention, there is provided a gas-liquid mixing apparatus comprising: a casing having a suction port for sucking a liquid; and a discharge port for discharging the liquid sucked from the suction port; An impeller formed with a number of blades, and a flow path formed in the casing along the outer periphery of the impeller and guiding liquid sucked from the suction port to the discharge port, the liquid in the flow path The area in the direction perpendicular to the flowing direction of the single-stage regenerating pump is formed substantially constant within the section from the suction port to the discharge port in the liquid flowing direction. A gas inflow means for feeding gas into the pressured liquid from the middle of the flow path in which the pressure of the liquid is gradually increased toward the discharge port side is provided.

According to the first, third and fourth aspects of the present invention, when the impeller of the one-stage pump is driven to rotate, the liquid is sucked from the suction port,
The sucked liquid is sent to the channel and discharged from the discharge port. And although the pressure of the liquid in the suction port is low,
The pressure of the liquid sucked from the suction port gradually increases while passing through the flow path, and the high-pressure liquid is discharged from the discharge port. As described above, the reason why the pressure becomes high when the liquid passes through the flow path is that the width of the flow path (the area in the direction perpendicular to the direction in which the liquid flows in the flow path) is from the suction port side to the discharge port side. It is because it becomes narrow according to. Also, the gas inflow means,
A gas can be fed into the pressure liquid from the middle of the flow path through which the pressure liquid in which the pressure of the liquid is sequentially increased is passed. Thereby, the impeller can stir the liquid mixed with the gas under a high pressure in a section from the middle of the flow path into which the gas is sent to the discharge port, so that the gas is dissolved and dispersed in the liquid. be able to.

According to the second aspect of the present invention, a narrow portion (a portion where the area of the flow channel in a direction perpendicular to the liquid flowing direction is reduced) is provided in the middle of the flow channel. The pressure in the flow path on the mouth side can be increased. Gas can be sent into the pressurized liquid by the gas inflow means. Therefore, the impeller can stir the liquid mixed with the gas under a high pressure in a section from the narrow portion to the discharge port, so that the gas can be dissolved and dispersed in the liquid.

According to a fifth aspect of the present invention, the partitioning means is provided in the middle of the flow path in a non-contact state with the impeller, whereby the pressure in the flow path on the suction port side with respect to the partitioning means can be increased. it can. In other words, the part provided with the partition means of the flow path,
The area in the direction perpendicular to the direction in which the liquid flows is reduced, so that the pressure of the liquid in the flow path on the suction port side of the partition means can be increased. Gas can be sent into the pressurized liquid by the gas inflow means. Therefore, the impeller can stir the liquid mixed with the gas under a high pressure in a section from the rear side of the partitioning means to the discharge port, so that the gas can be dissolved and dispersed in the liquid.

According to the sixth aspect of the present invention, the fluid pressure in the flow path can be set to a desired pressure by providing a suitable number of partition means. According to the seventh aspect, by providing the pressure reducing device, the liquid discharged from the discharge port can be reduced to a desired pressure.

According to the eighth aspect, when the impeller of the one-stage centrifugal pump is driven to rotate, the liquid is sucked from the suction port,
The sucked liquid is sent to the channel and discharged from the discharge port. The liquid sucked from the suction port is subjected to centrifugal force by the impeller and discharged from the discharge port at high pressure. Further, the gas inflow means supplies gas to a gap formed between a side surface formed on the side opposite to the side surface on which the flow path of the impeller is formed, and an inner wall surface of the casing facing the side surface. Can be sent. The gas sent into the gap is sent into the pressurized liquid existing on the outer peripheral portion of the impeller due to the centrifugal force of the impeller along with the liquid present in the gap. Accordingly, the impeller can stir the liquid mixed with the gas under a high pressure, so that the gas can be dissolved and dispersed in the liquid. In addition, since the gas inflow means sends the gas not to the flow path of the liquid but to the gap, the gas does not cause the impeller blades to idle, so that the liquid can be discharged at a high pressure from the discharge port. .

According to the ninth aspect, when the impeller of the single-stage regeneration pump is driven to rotate, the liquid is sucked from the suction port, and the sucked liquid is sent to the flow path and discharged from the discharge port. Although the pressure of the liquid in the suction port is low, the pressure of the liquid sucked from the suction port increases gradually while passing through the flow path, and the high-pressure liquid is discharged from the discharge port.
The reason why the pressure becomes high when the liquid passes through the flow path is that the impeller pushes the liquid into the flow path on the discharge port side by fluid friction. Further, the gas inflow means can feed gas into the pressure liquid from the middle of the flow path through which the pressure liquid in which the pressure of the liquid is sequentially increased. Thereby, the impeller can stir the liquid mixed with the gas under a high pressure in a section from the middle of the flow path into which the gas is sent to the discharge port, so that the gas is dissolved and dispersed in the liquid. be able to.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIG. The gas-liquid mixing device of this embodiment is an example corresponding to the gas-liquid mixing device according to claim 3, and is used, for example, in a flotation separation method in a wastewater treatment process. That is, the gas-liquid mixing device shown in FIG.
(Refer to FIG. 15) The fresh water 28 containing no suspended solids is sucked in, and air is dissolved and dispersed in the fresh water 28 under high pressure, and the fresh water in which the air is dissolved is depressurized. It is supplied into the sewage 29 containing suspended substances (see FIG. 15). Then, as described in the conventional example, when the air bubbles 30 float on the wastewater 29 and adhere to the floating substance, the specific gravity of the floating substance can be reduced, and the floating substance having the reduced specific gravity is transferred to the surface of the wastewater. To separate it.

In FIG. 1, reference numeral 43 denotes a one-stage regeneration pump (cascade pump), and reference numeral 34 denotes a gas inflow means. The one-stage regeneration pump 43 includes a casing 44, an impeller 47, and a flow path 48, and can send out water by fluid friction. As shown in FIG. 1, the casing 44 has a suction port 52 for sucking water and a discharge port 53 for discharging water sucked from the suction port 52. As shown in FIGS. 1 and 2A, one impeller 47 is provided in the casing 44, and a large number of blades 47b are provided on the outer peripheral portion of the disk 47a.
Are formed. A shaft 54 is connected to the center of the impeller 47, and the shaft 54 is rotatably supported by a bearing.

As shown in FIG. 1, the impeller 4
7 is formed in the casing 44 along the outer periphery of
The water drawn from the suction port 52 is guided to the discharge port 53. FIG. 2A is a cross-sectional view of FIG. 1 viewed from the AA direction, and FIG. 2B is a diagram illustrating a flow path 48 in a range from B to C shown in FIG. It is a development view seen from toward the center. Thus, as can be seen from FIG.
The flow path 48 is formed such that the width W of the inner wall surface of the casing 44 forming the flow path 48 becomes narrower as going from the suction port 52 side to the discharge port 53 side.
The area S in the direction perpendicular to the flow direction 55 of the water in the flow path 48 becomes smaller from the suction port 52 side to the discharge port 53 side.

Although not shown, the single-stage regeneration pump 43 has a shaft 54 connected to a motor, and is driven to rotate by this motor. Then, the suction port 52 shown in FIG.
Is connected to one end of a suction pipe 36, and the suction pipe 3
The other end of 6 is immersed in clear water 28 shown in FIG. One end of a T-shaped connection pipe 45 is connected to the discharge port 53, and the other end of the T-shaped connection pipe 45 is connected to another end of the T-shaped connection pipe 45 via a pressure reducing device (pressure reducing valve) 33. The discharge pipe 46 is connected. The decompression device 33 decompresses high-pressure fresh water in which the air flowing in from the inlet is dissolved or the like to approximately atmospheric pressure, and discharges it through the outlet and the discharge pipe 46. The other end of the discharge pipe 46 is immersed in the sewage 29 containing a suspended substance shown in FIG. And still another end of the T-shaped connection pipe 45 is:
It communicates with an injector 13 described later via a communication pipe 56 and the like.

The gas inflow means 34 is a means for sending air into the pressurized water from the middle of the flow path 48 in which the pressure of the water is gradually increased. As shown in FIG.
3 is provided. The injector 13 is shown in FIG. 3 and is the same as the conventional one, so that the detailed description is omitted. In the injector 13, one end of a communication pipe 57 is connected to the inlet 17 of the nozzle 14, and the other end of the communication pipe 57 is connected to one end of the T-shaped connection pipe 45 via the communication pipe 56. I have. One end of a communication pipe 58 is connected to the outlet 20 of the blowing section 15 of the injector 13, and the other end of the communication pipe 58 communicates with the flow path 48 via the communication pipe 59. This communication pipe 59 is, as shown in FIG.
The flow path 4 is located at a substantially intermediate position D of the B to C portions of the flow path 48.
8 and is connected to the casing 44.
Further, a communication pipe 49 is connected to the air intake port 16 of the injector 13, and a valve 50 is connected to the communication pipe 49.
Is provided. The other opening of the valve 50 is open to the atmosphere.

Reference numerals 51 and 51 shown in FIG. 1 denote pressure gauges.
This is for measuring the pressure in the T-shaped connection pipe 45 and the communication pipe 59.

Next, a procedure for producing fresh water in which air is dissolved and dispersed by the gas-liquid mixing apparatus having the above-described structure will be described. First, the one-stage regeneration pump 43 is driven to rotate. Then, the one-stage regeneration pump 43 sucks the fresh water 28 from the suction port 52 and discharges it from the discharge port 53. Part of the fresh water discharged from the discharge port 53 flows into the decompression device 33 through the T-shaped connection pipe 45, is depressurized to approximately atmospheric pressure by the decompression device 33, and is discharged from the discharge pipe 46. On the other hand, a part of the fresh water discharged from the discharge port 53 is branched by the T-shaped connection pipe 45, passes through the injector 13, and the fresh water that has passed through the injector 13 flows into the intermediate position D of the flow path 48 and is sucked. Mouth 5
It merges with the fresh water 28 sucked in from 2 and flows again to the discharge port 53 side to be discharged. Thus, the injector 1
3 and the valve 50 of the injector 13
To release. Then, as described in the conventional example, the fresh water flowing in the injector 13 can draw in the air from the air intake 16 of the injector 13 and can be taken in.
Can squirt from.

The pressure of the fresh water 28 in the suction port 52 is low, but the pressure of the fresh water 28 sucked from the suction port 52 gradually increases while passing through the flow path 48, and the high-pressure fresh water 28 It is discharged from the discharge port 53. in this way,
The reason why the high pressure when the fresh water 28 passes through the flow path 48 is as follows.
This is because the width S (the area in the direction perpendicular to the direction in which the fresh water 28 flows in the flow path 48) S decreases from the suction port 52 side to the discharge port 53 side. In addition, the gas inflow means 34 can feed fresh water containing air into the pressure fresh water 28 from the middle D of the flow path 48 through which the pressure fresh water 28 is gradually increased in pressure. Accordingly, the impeller 47 can stir the high-pressure fresh water 28 mixed with the air in a section from the middle D of the flow path 48 into which the air is sent to the discharge port 53, so that a large amount of air is It can be efficiently dissolved and dispersed in the fresh water 28.

Then, the fresh water in which the air is dissolved or the like under high pressure is decompressed by the decompression device 33 and supplied into the sewage 29 containing the suspended substance under the atmospheric pressure shown in FIG. A large number of ultra-fine bubbles 30 are generated in the water 29, and the large number of bubbles 30 adhere to many floating substances when floating in the wastewater 29, and can reduce the specific gravity of each floating substance, The suspended matter having the reduced specific gravity can be floated on the sewage surface. The suspended matter thus floated can be efficiently separated from water and removed.

Further, according to the gas-liquid mixing apparatus, the regeneration pump 43 is of a single-stage type, so that the first pump 31 of the second conventional apparatus shown in FIG. The cost of the gas-liquid mixing device can be reduced, and the size and weight can be reduced.

The gas-liquid mixing device according to the second embodiment has the following features.
This is an example corresponding to the gas-liquid mixing device described in FIG. 1, and will be described with reference to FIGS. The difference between the gas-liquid mixing device of the first embodiment and the gas-liquid mixing device of the second embodiment is that the present invention is applied to the single-stage regeneration pump 43 in the first embodiment. The second embodiment is applied to a single-stage centrifugal pump 60 having an open impeller 62. 1
The step centrifugal pump 60 includes a casing 61, an impeller 62, a flow path 63, and partitioning means 70. Casing 6
1, as shown in FIG. 4, a suction port 64 that sucks water (fresh water) and guides the sucked water to the center portion 62 c of the impeller 62 and a discharge port 65 that discharges the water sucked from the suction port 64. Have. As shown in FIG. 4, one open impeller 62 is provided in the casing 61.
This is an open type in which eight blades 62b are formed on the side surface of the disk 62a on the side of the suction port 64. Each blade 62b
The disk 62a is formed in a spiral shape from the center to the outer periphery of the disk 62a at intervals. At the center of the impeller 62, a shaft 54 is connected and provided.
6 rotatably supported.

The channel 63 is, as shown in FIGS.
Eight blades 62b provided on the impeller 62 are formed between adjacent ones of the eight blades 62b.
The water that has been sucked in from the nozzle 4 and guided to the central portion 62c of the impeller 62 is guided to the discharge port 65 by centrifugal force. As shown in FIG. 5, each of the eight flow paths 63 has a space W between the inner surfaces of the two blades 62 b forming each flow path 63.
Thus, the area S in the direction perpendicular to the direction 67 of water flow in the flow channel 63 is increased toward the center (toward the suction port 64). ) Toward the outer peripheral side (discharge port 65 side).

The partitioning means 70 (70a, 70b, 70
c) is formed on the inner wall surface facing the blade 62b of the casing 61 in a non-contact state with the impeller 62 as shown in FIGS. 4 and 5, and has a center portion 62c of the impeller 62 concentric. Are three annular ridges different from each other. These three partitioning means 70a, 70b, 70c are provided at an interval from each other, and are arranged in a notch provided on each blade 62b with a gap from the inner edge of the notch. As described above, each flow path 63 is provided with three partitioning means 70a, 70
b, 70c, three first to third rooms 63a to 63c
3c. The spiral chamber 68 is formed outside the third chamber 63c. The space between the tip of each of the partitioning means 70a, 70b, 70c and the disk 62a of the impeller 62 is narrow, and this portion is a narrow portion 71 (71a, 71b, 71c). That is, the area S of the narrow portion 71 in the direction perpendicular to the direction 67 in which the water flows in the flow path 63 is sharply reduced. This narrow part 71
Is a narrow portion according to claim 2.

According to the partitioning means 70a, 70b, 70c, the velocity energy of the water passing through each of the narrow portions 71a, 71b, 71c can be converted into pressure energy. 2, the third room 63
The pressure can be increased in the order of a, 63b, 63c and the spiral chamber 68, and the pressure in the spiral chamber 68 becomes the maximum pressure.
The partitioning means 70 is provided with a large number of
3, the pressure of the water in the room can be increased to a desired pressure. However, the more the partitioning means 70 are provided, the more the discharge flow rate decreases, and in order to suppress the decrease in the discharge flow rate, the distance between the blades 62 is reduced. And the impeller 62
Needs to be increased in diameter. Therefore, the partitioning means 7
It is necessary to determine the number of 0 to be an appropriate number by comparing the water pressure in the room of the flow path 63 with the discharge flow rate of the pump 60.

Although not shown, the single-stage centrifugal pump 60 has a shaft 54 connected to a motor, and is driven to rotate by the motor. Then, the suction port 6 shown in FIG.
Although not shown in the drawing, one end of a suction pipe 36 is connected to 4 similarly to the first embodiment, and the other end of the suction pipe 36 is immersed in fresh water 28 shown in FIG. Although not shown in the figure, the discharge port 46 is connected to the discharge port 65 via a pressure reducing device 33 equivalent to that of the first embodiment via a connection pipe. The other end of the discharge pipe 46 is immersed in the sewage 29 containing floating substances shown in FIG. Then, as shown in FIG. 4, the injector 13 is connected to the spiral chamber 68 communicating with the discharge port 65 via a communication pipe 57 and the like.

The gas inflow means 34 feeds air into the pressurized water in the third chamber 63c among the first to third chambers 63a to 63c formed in the channel 63 in which the pressure of the water is sequentially increased. It is a means for sending. This gas inflow means 3
Reference numeral 4 is equivalent to that of the first embodiment, and a detailed description is omitted. The outlet 20 of the blowing section 15 of the injector 13 of the gas inflow means 34 is connected to communication pipes 58 and 59.
Through the third room 63c.

A pressure gauge 51 shown in FIG. 4 is used to measure the pressure in the communication pipe 59. Although not shown in the figure, a pressure gauge for measuring the pressure in the discharge port 65 is also provided.

Next, a procedure for producing fresh water in which air is dissolved and dispersed by the gas-liquid mixing apparatus having the above structure will be described. First, the one-stage centrifugal pump 60 is rotationally driven. Then, the single-stage centrifugal pump 60 sucks the fresh water 28 from the suction port 64 and passes through the flow path 63 and the spiral chamber 68 to the discharge port 6.
Discharge from 5. The pressure clean water discharged from the discharge port 65 flows into the decompression device 33 through the communication pipe (not shown) as in the first embodiment, and is depressurized to approximately atmospheric pressure by the decompression device 33, and is discharged from the discharge pipe 46. Discharge. On the other hand, the spiral chamber 6
A portion of the pressurized clean water sent to 8 passes through the communication pipe 57 and the injector 13, and the clean water that has passed through the injector 13 flows into the third chamber 63 c of the channel 63 and is sucked through the suction port 64. It merges with the incoming fresh water 28 and flows again to the discharge port 65 side to be discharged. The injector 1
3, as described in the conventional example, the fresh water flowing in the injector 13 can draw in the air from the air intake 16 of the injector 13 and can be drawn in, and discharge the fresh water containing the air from the outlet 20 of the blowing unit 15. be able to.

The pressure of the fresh water 28 in the suction port 64 is low, but the pressure of the fresh water 28 sucked through the suction port 64 is low.
The pressure is increased in the order of 3c and the spiral chamber 68, and the high-pressure fresh water 28 is discharged from the discharge port 65. Thus, Shimizu 2
The reason why the pressure becomes high when the passage 8 passes through the flow path 63 is that the partitioning means 70a to 70c are provided in the middle of the flow path 63 and the narrow portions 71a to
This is because 71c is formed. Further, the gas inflow means 34 can feed the pressure fresh water containing air into the pressure fresh water 28 in the third chamber 63c. As a result, the impeller 62 moves into the third chamber 63c into which the air has been sent.
Vanes 62b located in the spiral chamber 68 inside and outside thereof
Accordingly, the fresh water 28 into which the air is mixed can be stirred under a high pressure, so that a large amount of air can be efficiently dissolved and dispersed in the fresh water 28.

Then, the fresh water in which the air is dissolved or the like under high pressure is depressurized by the decompression device 33 and supplied into the sewage 29 containing the suspended substance under the atmospheric pressure. Similarly, a large number of ultrafine bubbles 30 can be generated in the sewage 29, and floating substances can be floated on the sewage surface. The suspended matter thus floated can be efficiently separated from water and removed.

Further, according to the gas-liquid mixing device, as in the first embodiment, the centrifugal pump 60 is of a single-stage type, so that the first pump 31 of the second conventional device shown in FIG.
Is unnecessary, so that the cost of the gas-liquid mixing device can be reduced, and the size and weight can be reduced.

A gas-liquid mixing device according to a third embodiment will be described with reference to FIGS. The difference between the gas-liquid mixing device of the second embodiment and the gas-liquid mixing device of the third embodiment is that the one-stage centrifugal pump 60 is different from the open-type impeller 6 in the second embodiment.
In contrast to the second embodiment, the third embodiment includes a closed impeller 72. Except for this, the second embodiment is equivalent to the second embodiment, and the same parts are denoted by the same reference numerals.
Detailed description thereof will be omitted. The sealed impeller 72 is
As shown in FIGS. 6 and 7, an annular front enclosing plate 72a is provided at a position facing the open impeller 62 of the second embodiment at an interval from the circular plate 62a. Eight blades 62b are provided between the front surrounding plate 72a and the circular plate 62a.
Is located.

By using the closed impeller 72, the pump efficiency can be improved. Except for this, it operates in the same manner as the gas-liquid mixing device of the second embodiment, and a large amount of air can be efficiently dissolved and dispersed in the fresh water 28.

Next, a fourth embodiment will be described with reference to FIG. The gas-liquid mixing device of this embodiment corresponds to the invention according to claim 8. The difference between the gas-liquid mixing device of the second embodiment and the gas-liquid mixing device of the third embodiment is that the outlet 20 of the blowing section 15 of the injector 13 of the gas inflow means 34 is shown in FIG. 4 in the second embodiment. Communication pipe 5
In the fourth embodiment, the communication pipe 5 communicates with the third chamber 63c via the communication pipes 5 and 59, as shown in FIG.
A side surface formed on the side opposite to the side surface on which the flow path 63 of the disk 62a of the impeller 62 is formed via the 8, 8;
It is in communication with a gap 61a formed between the inner wall surface of the casing 61 facing the side surface. Except for this, the second embodiment is the same as the second embodiment, and the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted.

The gas inflow means 34 can supply high-pressure water into which air is mixed into the gap 61a between the casing 61 and the disk 62a of the impeller 62. The high-pressure water into which the air sent into this gap 61a is mixed Is a spiral chamber 68 formed on the outer periphery of the impeller 62 by the centrifugal force of the impeller 62.
Into the water. Thereby, the impeller 62
Can stir high-pressure water mixed with air under the high pressure, so that air can be efficiently dissolved and dispersed in water. Since the gas inflow means 34 feeds high-pressure water into which air is mixed into the gap 61a instead of the flow path 63, the impeller 6
The second blade 62b does not run idle, so that water can be discharged from the discharge port 65 at a high pressure. In this embodiment, partitioning means 70a to 70c are provided, and the partitioning means 70 prevents the air in the spiral chamber 68 from moving toward the suction port 64 through the flow path 63. However, the number of the partitioning means 70a to 70c
It can be adjusted according to the flow rate of the water flowing inside and the amount of air, and can be omitted in some cases. Except for this, it operates in the same manner as the gas-liquid mixing device of the second embodiment, and a large amount of air can be efficiently dissolved and dispersed in the fresh water 28.

However, the single-stage regeneration pump 4 of the first embodiment
3B, the width W of the channel 48 is formed so as to become narrower from the suction port 52 side to the discharge port 53 side, as shown in the developed view of FIG. Although the water pressure was set to be high, the structure of the flow path 48 was changed as shown in FIG.
Instead of the configuration shown in FIG. 8B, as shown in a development view of FIG. 8A and a partial cross-sectional view shown in FIG. , Its flow path 48
Partitioning means 73a formed of four sets of ridges on both inner wall surfaces of
73b, 73c, and 73d may be provided at a predetermined interval from each other. This partitioning means 73a, 73
b, 73c, 73d have the same function as the partitioning means 70a to 70c of the second and third embodiments, and the suction ports 52 of the respective partitioning means 73a, 73b, 73c, 73d.
First, second, third and fourth chambers 48a formed on the side
The water pressure in 48b, 48c, 48d is sequentially increased in this order, and the water pressure in the fourth room 48d becomes the highest.
Then, the high-pressure water discharged from the discharge port 53 is sent into the third chamber 48c having a lower pressure but relatively high-pressure water flowing therein, and thereby a large amount of air is discharged similarly to the above-described embodiments. It can be efficiently dissolved and dispersed in the fresh water 28.

Further, the single-stage regeneration pump 43 of the first embodiment
The flow path 48 may have another form. That is, FIG.
As shown in FIG. 3, the area in the direction perpendicular to the flowing direction of the fresh water in the flow path 48 is changed from the suction port 52 to the discharge port 53 (B to B).
C) is formed substantially constant, and a partitioning means 79 is provided from the discharge port 53 to the suction port 52 (a section other than BC) so as to be narrower than that. According to the one-stage regeneration pump 43, when the impeller 47 is rotationally driven, fresh water is sucked from the suction port 52 and the sucked fresh water is passed through the flow path 48.
And discharged from the discharge port 53. The pressure of the fresh water in the suction port 52 is low, but the pressure of the fresh water sucked from the suction port 52 gradually increases while passing through the flow path 48, and the high-pressure fresh water is discharged from the discharge port 53. Is done. As described above, the reason why the high pressure is applied when the fresh water passes through the flow path 48 is that the impeller 47 causes the fresh water to flow through the discharge port 53 by the fluid friction.
This is because it can be pushed into the flow path 48 surrounded by the partitioning means 79 on the side. Further, the gas inflow means 34 can send air together with the fresh water into the pressure fresh water from the middle D of the flow passage 48 through which the pressure fresh water is gradually increased in pressure. Thereby, the impeller 47 can stir the high-pressure fresh water mixed with the air in a section from the middle of the flow path 48 into which the air is sent to the discharge port 53, and thus remove a large amount of air. Can be efficiently dissolved and dispersed.

In the second and fourth embodiments, as shown in FIG. 5, each of the eight flow channels 63 has a suction space W between the inner surfaces of the two blades 62b forming each flow channel 63. It is formed so as to become wider as going from the port 64 side to the discharge port 65 side.
7, the area S in the direction perpendicular to the central portion (the suction port 64)
Side) toward the outer peripheral side (discharge port 65 side), but may be configured as shown in FIG. 9 or FIG.

Each of the eight flow paths 75 of the impeller 74 shown in FIG.
The distance W between the inner surfaces of the two blades 74b forming each flow path 75 is substantially the same at each point from the suction port 64 side to the discharge port 65 side. The area S in the direction perpendicular to the flowing direction 67 is substantially the same at each point from the center portion side (the suction port 64 side) to the outer peripheral portion side (the discharge port 65 side). Other than this, it is equivalent to the impeller 62.

Each of the eight flow paths 7 of the impeller 76 shown in FIG.
7 is formed such that the interval W between the inner surfaces of the two blades 76b forming each flow path 77 becomes narrower from the suction port 64 side to the discharge port 65 side. Area S perpendicular to the direction 67 of water flow
From the center portion side (suction port 64 side) to the outer peripheral portion side (discharge port 6).
5). Other than this, it is equivalent to the impeller 62. By making the area S of the flow path 77 narrower toward the water flowing direction 67, the water pressure in the flow path 77 is reduced toward the center (the suction port 64 side).
To the outer peripheral side (discharge port 65 side).

The impeller 74 shown in FIG. 9 and FIG.
Although 76 is an open type, it may be of a closed type in which a front enclosing plate 72a is provided on each of the impellers 74 and 76 as in the third embodiment shown in FIGS.

In the second and fourth embodiments, the partitioning means 70a, 70b, 70c shown in FIGS. 4 and 5 are omitted, and the open impeller 78 shown in FIG. It is good also as a gas-liquid mixing device of the structure provided with.
The impeller 78 shown in FIG. 11 is obtained by omitting notches (three notches formed on concentric circles) for passing the partitioning means 70a, 70b, 70c of the impeller 76 shown in FIG. It is equivalent to the car 76. Of course, FIG.
Instead of providing the open impeller 78 shown in FIG. 7, a gas-liquid mixing device having a configuration in which a closed impeller having the front enclosing plate 72a provided on the impeller 78 may be provided, though not shown.

Further, in the second, third, and fourth embodiments, three partition means 70a to 70c are provided, but one or four or more partition means other than three may be provided. Good. In the second and third embodiments, the outlet 20 of the blow-out portion 15 of the injector 13 of the gas inflow means 34 is connected to the third chamber 63 c via the communication pipe 59.
However, the outlet 20 of the blowing section 15 of the injector 13 is connected to the first or second chamber 63a or 63a.
It may be configured to communicate with b. In the first to fourth embodiments, the decompression device 33 is provided. However, the decompression device 33 may be omitted, and a configuration in which water in which air is dissolved or the like is discharged from the discharge port at a high speed may be used. .

Further, in the first to fourth embodiments, air is mixed into the fresh water 28 using the injectors 13. However, the injectors 13 are not provided, and the air passes through positions corresponding to the injectors 13. It is possible to adopt a configuration in which a predetermined amount of air is forcibly mixed into fresh water. As a device for forcibly supplying air, for example, a compressor can be used. However, it is necessary to provide a flow control valve at the air discharge port of the compressor in order to adjust the amount of supplied air. Of course, the injector 13 and the communication pipe communicating therewith may be omitted, and the compressed air may be directly sent to the position D in the flow path or the pressurized water in the third room, or the compressed air may be introduced into the gap 61a. It is good also as a structure which sends directly.

In the first to fourth embodiments,
The fresh water is sucked in, the air is dissolved and dispersed in the fresh water, and the fresh water in which the air is dissolved is supplied to the sewage containing the floating substance, and the floating substance floats on the surface of the sewage. Instead, the sewage to be purified may be sucked in, the air may be dissolved and dispersed in the sewage, and the sewage in which the air has been dissolved may be returned to the original sewage to float the suspended solids.

Further, in the first to fourth embodiments, the gas-liquid mixing device of the present invention is used in the flotation method in the wastewater treatment step, but may be used for other purposes. For example, the present invention can be applied to a cleaning device using ultrasonic waves generated when air bubbles burst. in this case,
Air may be dissolved and dispersed in the cleaning liquid. By generating air bubbles in the bath water, it can be used for body washing and massage. Furthermore,
It can also be used as a device for purifying lakes and marshes. Further, a gas, for example, carbon dioxide gas or ozone gas, can be mixed and dissolved in a liquid, for example, water to produce carbonated water or ozone water, or a gas can be mixed and dissolved in a liquid,
It can also be used for a process of chemically reacting a gas and a liquid.

[0061]

According to the gas-liquid mixing apparatus of the present invention, the gas is fed into the high-pressure liquid passing through the middle of the flow path of the single-stage pump to mix the gas and the liquid under high pressure.
The first pump 31 of the second conventional apparatus shown in FIG. 5 is unnecessary, so that the cost of the gas-liquid mixing apparatus can be reduced accordingly, and the size and weight can be reduced. Then, since gas is sent into the high-pressure liquid passing through the middle of the flow path and the gas and the liquid are mixed under high pressure, a large amount of gas is efficiently dissolved in the liquid as in the conventional apparatus shown in FIG. There is an effect that it can be dispersed.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a gas-liquid mixing device according to a first embodiment of the present invention.

FIG. 2A is a cross-sectional view of the single-stage regenerating pump of the gas-liquid mixing device according to the first embodiment, viewed from the AA direction in FIG. 1;
(B) is a development view showing a flow path of the single-stage regeneration pump.

FIG. 3 is an enlarged sectional view of the injector according to the first to third embodiments.

FIG. 4 is a front sectional view showing a gas-liquid mixing device according to a second embodiment of the present invention.

FIG. 5 is a front view showing an impeller and partitioning means of the second embodiment.

FIG. 6 is a front sectional view showing a gas-liquid mixing device according to a third embodiment of the present invention.

FIG. 7 is a front view showing an impeller and a partitioning unit of the third embodiment.

FIG. 8 is a diagram showing another example of the single-stage regeneration pump of the gas-liquid mixing device according to the first embodiment, wherein (a) is one of the other examples.
FIG. 2B is a development view showing a flow path of the stage regeneration pump, and FIG. 2B is a partial cross-sectional view of a one-stage regeneration pump of another example.

FIG. 9 is a front view showing another first example of the impeller of the second embodiment.

FIG. 10 is a front view showing another second example of the impeller of the second embodiment.

FIG. 11 is a front view showing another third example of the impeller of the second embodiment.

FIG. 12 is a front sectional view showing a gas-liquid mixing device according to a fourth embodiment of the present invention.

FIG. 13 is a view showing still another example of the single-stage regeneration pump of the gas-liquid mixing device according to the first embodiment, and is a developed view showing a flow path thereof.

FIG. 14 is a front view showing a conventional gas-liquid mixing device.

FIG. 15 is a front view showing another conventional gas-liquid mixing device.

[Explanation of symbols]

 28 Fresh water 29 Sewage water 30 Bubbles 43 One-stage regeneration pump 47, 62, 72 Impeller 48, 63 Channel 52, 64 Suction port 53, 65 Discharge port 60 One-stage centrifugal pump 68 Spiral chamber 70 (70a-70b) Partition Means 71 (71a-71b) Narrow part

Claims (9)

[Claims] 1. A casing having a suction port for sucking liquid, a discharge port for discharging liquid sucked from the suction port, an impeller provided in the casing, and a liquid sucked from the suction port. And a flow path leading to the discharge port, wherein the area of the flow path in a direction perpendicular to the direction in which the liquid flows, the area of the single-stage pump becomes narrower from the suction port side toward the discharge port side. A gas-liquid mixing device, comprising: gas inflow means for feeding gas into the pressured liquid from the middle of the flow path in which the pressure of the liquid is gradually increased from the suction port side toward the discharge port side. 2. A casing having a suction port for sucking liquid, a discharge port for discharging liquid sucked from the suction port, an impeller provided in the casing, and a liquid sucked from the suction port. A flow path leading to the discharge port, wherein the narrow part provided in the middle of the flow path and having a small area in a direction perpendicular to the direction of flow of the liquid in the flow path is narrower than the narrow part. A gas inflow means for feeding gas into the pressure liquid in the flow path on the suction port side. 3. A casing having a suction port for sucking a liquid, a discharge port for discharging the liquid sucked from the suction port, and a plurality of blades formed in an outer peripheral portion of a disk provided in the casing. A car, and a flow path formed in the casing along the outer periphery of the impeller and guiding the liquid sucked from the suction port to the discharge port, a direction perpendicular to a direction in which the liquid flows in the flow path. In the single-stage regeneration pump, the area of which is reduced from the suction port side to the discharge port side, wherein the pressure of the liquid is sequentially increased from the suction port side to the discharge port side. A gas-liquid mixing device comprising a gas inflow means for feeding gas into the pressure liquid from the middle. 4. A casing, an impeller provided in the casing, a suction port provided in the casing to guide a sucked liquid to a center portion of the impeller, and a suction port provided in the casing. A discharge port for discharging the liquid sucked more, and a flow path formed from the center to the outer periphery of the impeller and guiding the liquid sucked from the suction port to the discharge port, the liquid in the flow path In a one-stage centrifugal pump in which the area in the direction perpendicular to the flowing direction of the impeller decreases from the center toward the outer periphery of the impeller, from the center to the outer periphery of the impeller A gas inflow means for feeding gas into the pressured liquid from the middle of the flow path in which the pressure of the liquid is sequentially increased according to the following. 5. A casing, an impeller provided in the casing, a suction port provided in the casing to guide a sucked liquid to a center portion of the impeller, and a suction port provided in the casing. A single-stage centrifugal pump comprising: a discharge port for discharging more sucked liquid; and a flow path formed from a center portion to an outer peripheral portion of the impeller and guiding the liquid sucked from the suction port to the discharge port. An annular partitioning means formed on the inner surface of the casing in a non-contact state with the impeller and surrounding a center of the impeller; and an annular partitioning means between the partitioning means and the center of the impeller. Gas inflow means for sending gas into the pressure liquid of
A gas-liquid mixing device comprising: 6. A gas-liquid mixing apparatus according to claim 5, wherein a plurality of said annular partitioning means are provided. 7. The gas-liquid mixing device according to claim 1, wherein a pressure reducing device for reducing and sending the liquid discharged from the discharge port is provided at the discharge port. A gas-liquid mixing device. 8. A casing, an impeller provided in the casing, a suction port provided in the casing to guide a sucked liquid to a center portion of the impeller, and a suction port provided in the casing. A single-stage centrifugal pump comprising: a discharge port for discharging more sucked liquid; and a flow path formed from a center portion to an outer peripheral portion of the impeller and guiding the liquid sucked from the suction port to the discharge port. Gas inflowing gas into a gap formed between a side surface of the impeller opposite to the side surface on which the flow path is formed, and an inner wall surface of the casing facing the side surface. A gas-liquid mixing device comprising means. 9. A casing having a suction port for sucking a liquid, a discharge port for discharging the liquid sucked from the suction port, and a plurality of blades provided in the casing and formed on an outer peripheral portion of a disk. A car, and a flow path formed in the casing along the outer periphery of the impeller and guiding the liquid sucked from the suction port to the discharge port, a direction perpendicular to a direction in which the liquid flows in the flow path. In a one-stage regenerating pump, the area of which is formed substantially constant within a section from the suction port to the discharge port in the direction in which the liquid flows, the pressure of the liquid increases from the suction port side to the discharge port side. A gas inflow means for feeding gas into the pressured liquid from the middle of the flow path in which the pressure is sequentially increased.