JP2002346356A - Gas/liquid mixing dissolving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas/liquid mixing dissolving device capable of enhancing the dissolution efficiency of the gas and reducing cost and noise. SOLUTION: A cylindrical body 23 is inserted into the liquid of a liquid tank 21 and the liquid and the gas are suctioned from an upper part of this cylindrical body 23. The liquid and the gas in the cylindrical body 23 are suctioned to a lower part of the cylindrical body 23 while they are stirred and mixed and a pump 24 for discharging them to the periphery is provided on the lower part of the cylindrical body 23. The dissolution efficiency of gas is enhanced by continuously carrying out gas dissolving treatments at three stages, i.e., the dissolution of the gas by a gas/liquid stirring mixing action in the cylindrical body 23 generated by the suction force of the pump; the dissolution of the gas by a gas/liquid stirring mixing action in the pump 24; and the dissolution of the gas when bubbles 59 discharged from the pump 24 into the liquid are floated up in the liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a gas-liquid mixing and dissolving apparatus for dissolving a gas in a liquid.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 7, when oxygen is dissolved in a liquid 12 in a liquid tank 11 for aeration treatment, a forced air supply device 13 such as a compressor or a blower is used to pressurize the oxygen. The air thus supplied is supplied to a nozzle 14 provided at the bottom of the liquid tank 11, and countless air bubbles 15 are generated by forcibly blowing air from the nozzle 14 into the liquid in the liquid tank 11, thereby generating air bubbles 15 The oxygen inside is dissolved in the liquid in the liquid tank 11. In addition,
The liquid before the treatment flows into the liquid tank 11 through the inlet pipe 16, and the liquid after the treatment flows out of the liquid tank 11 through the outlet pipe 17.

[0003]

The oxygen in the bubbles is dissolved in the liquid in the liquid tank 11 only while the bubbles 15 ejected from the nozzle 14 float up to the liquid surface in the liquid tank 11. Dissolution efficiency is not good.

Further, the forced air supply device 13 such as a compressor or a blower consumes a large amount of electric power. In particular, the deeper the liquid tank 11, the more it is necessary to forcibly blow the pressurized air to the bottom of the liquid tank 11 against the water pressure. The noise generated from the ventilation device 13 also increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a gas-liquid mixing and dissolving apparatus capable of improving gas dissolving efficiency and reducing cost and noise.

[0006]

According to the present invention, a cylinder inserted into a liquid and sucking the liquid and gas from the upper part, and a liquid and a gas provided in the lower part of the cylinder are agitated. A gas-liquid mixing and dissolving device including a pump that sucks while mixing and discharges the gas to the surroundings. By performing gas dissolution processing in three stages, that is, gas dissolution due to the above and gas dissolution when bubbles discharged into the liquid from the pump float in the liquid, high gas dissolution efficiency can be obtained.

According to a second aspect of the present invention, there is provided a gas-liquid mixing and dissolving apparatus according to the first aspect, wherein the cylinder has a liquid suction port opened in the liquid and the liquid sucked into the inside from the liquid suction port. Is a gas-liquid mixing and dissolving device equipped with a straight cylinder part that allows the liquid to fall in a waterfall shape.The liquid level in the straight cylinder part decreases due to the suction action of the pump, and the liquid sucked into the straight cylinder part from the liquid suction port is Since gas flows down like a waterfall while entraining gas, gas can be efficiently sucked at atmospheric pressure without using a forced air supply device such as a conventional compressor or blower, and the cost of energy required to drive the pump is reduced. Noise can be reduced as well as reduced.

According to a third aspect of the present invention, there is provided a gas-liquid mixing and dissolving apparatus in which the liquid suction port of the gas-liquid mixing and dissolving apparatus according to the second aspect is provided in a tangential direction of the straight cylindrical portion. The liquid sucked from the liquid suction port becomes a swirling flow inside the straight cylindrical part and flows down so that the central part is concave, so the gas is efficiently caught in the concave part of the central part and a forced air supply device is used It can be efficiently sucked under atmospheric pressure without any.

According to a fourth aspect of the present invention, in the gas-liquid mixing and dissolving apparatus according to the second or third aspect, the cylindrical body is provided at a lower portion of the straight cylindrical portion and has a tapered cylindrical portion having a gradually decreasing diameter toward the lower side. The liquid and gas flowed into the straight cylinder part from the liquid suction port as a waterfall by the suction action of the pump, generating a strong cyclone-like turbulent flow inside the tapered cylinder part. Therefore, the gas-liquid can be efficiently stirred and mixed in the tapered cylindrical portion, and the gas dissolving efficiency can be improved.

According to a fifth aspect of the present invention, there is provided a gas-liquid mixing / dissolving apparatus according to any one of the first to fourth aspects, wherein the pump is rotatably provided inside the casing fixed to the lower end of the cylindrical body. A gas-liquid mixing and dissolving device including a pump blade provided, a main shaft connected to the center of the pump blade, and a driving device for rotating the main shaft, in a casing of the pump inserted into the liquid together with the cylinder. In this case, the gas and liquid are stirred and mixed while rotating by the pump blades under pressure, so that the gas can be dissolved in the liquid at a high concentration, and the liquid pressure corresponding to the liquid depth is provided on both the suction side and the discharge side of the casing. The pump load is not easily influenced by the depth in the liquid, so the energy required to drive the pump is not required when gas is blown into the liquid using a forced air supply device such as a compressor or blower. It is possible to reduce strike and noise. Also,
The three-stage gas dissolution process can be efficiently performed by only one driving device.

According to a sixth aspect of the present invention, there is provided a gas-liquid mixing and dissolving apparatus according to the fifth aspect, wherein the casing is formed in a cylindrical shape and includes a plurality of discharge nozzles protruding from the cylindrical peripheral surface of the casing. A liquid mixing and dissolving device that continuously disperses a gas dissolved liquid and a large amount of microbubbles generated by stirring and mixing by a pump blade in a casing over a wide area around the casing from a plurality of discharge nozzles protruding from the cylindrical peripheral surface of the casing. Can be dispersed and discharged. The dispersed gas discharge liquid is mixed with the liquid around the pump to increase the dissolved oxygen value of the liquid, and the small bubbles dissolve the gas in the bubbles in the contacted liquid while floating to the liquid surface. Can be.

According to a seventh aspect of the present invention, in the gas-liquid mixing and dissolving apparatus according to the fifth or sixth aspect, the pump blade comprises:
A gas-liquid mixing and dissolving apparatus comprising: a plurality of dish-shaped rotors attached at right angles to a main shaft; and a resistance increasing unit provided on at least a facing surface of the rotors to increase surface resistance of the rotors. A plurality of dish-shaped rotors mounted at right angles to the main shaft are capable of high-speed rotation, and agitating the liquid at high speed by means of resistance increase between them to create fine turbulence on the surface of the rotor. By generating an infinite number of fine bubbles efficiently, the gas dissolution ratio in the liquid can be significantly increased, and the gas-liquid mixture with a high gas dissolution ratio does not cause performance degradation, It can be transferred by centrifugal force by high-speed rotation and discharged into the liquid around the pump. Further, since only the surface resistance of the dish-shaped rotor attached to the main shaft at right angles is increased by the resistance increasing means, clogging in the pump and entanglement of impurities can be prevented.

According to an eighth aspect of the present invention, there is provided a gas-liquid mixing and dissolving apparatus according to the seventh aspect, wherein the plurality of dish-shaped rotating blades comprises:
It is a gas-liquid mixing and dissolving apparatus having a bent peripheral part bent obliquely downward, and a resistance increasing means provided radially in the bent peripheral part. Due to the centrifugal force given by the radial resistance increasing means, the gas-liquid mixture directed diagonally downward is once discharged diagonally downward from the pump, and then turns into floating, so the time required for floating is saved, Dissolution of gas dissolved when floating in liquid can be more effectively performed.

According to a ninth aspect of the present invention, in the gas-liquid mixing and dissolving apparatus according to any one of the first to eighth aspects, the cylinder is fixed at an upper portion of the liquid tank, and the pump is provided near a bottom of the liquid tank. This is a gas-liquid mixing and dissolving device that is installed in the existing liquid tank, and can be installed by inserting this device from the top of the liquid tank. The dissolution efficiency can be improved, and the cost and noise of the energy required for driving the pump can be reduced as compared with the case where gas is blown into the liquid using a conventional forced air supply device such as a compressor or a blower.

The invention described in claim 10 is the fifth invention.
10. The driving device in the gas-liquid mixing and dissolving device according to any one of the above items 1 to 9, wherein the driving device is a gas-liquid mixing and dissolving device integrally provided below the pump, and the length of the main shaft of the pump blade is independent of the liquid depth. The size and diameter of the main shaft and the bearing structure that suppresses shaft run-out vibration can be made small and inexpensive, and the gas is sucked and mixed into the liquid by the cyclone phenomenon in the cylinder. At this time, it is not necessary to penetrate the main shaft, which is an obstacle, into the cylinder, so that the cyclone effect becomes larger and the amount of gas suction by the cyclone effect can be increased.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to one embodiment shown in FIGS. 1 to 3 and other embodiments shown in FIGS.

First, an embodiment shown in FIGS. 1 to 3 will be described.

FIG. 1 shows the entire gas-liquid mixing and dissolving apparatus.
A cylinder 23 inserted into the liquid is fixed to the upper edge of the liquid tank 21 via a mounting plate 22. The cylinder 23 sucks liquid and gas from above. At the lower part of the cylindrical body 23, there is provided a pump 24 which sucks in the liquid and gas in the cylindrical body 23 while stirring and mixing and discharges the liquid and gas to the surroundings. Pump 24
Is arranged near the bottom of the liquid tank 21.

An intake port 26 is provided above the liquid level 25 in the tank of the cylindrical body 23, and an intake pipe 27 is connected to the intake port 26. The tip of the intake pipe 27 is open to the atmosphere. A gas supply source may be connected to the intake pipe 27.

At a position below the liquid surface 25 in the tank of the cylindrical body 23, a plurality of liquid suction ports 28 opened in the liquid in the liquid tank 21 are provided in two stages. Note that the lower liquid suction port 28 may not be provided.

The cylindrical body 23 has a straight cylindrical portion 31 for dropping the liquid sucked into the inside from the liquid suction port 28 in a waterfall shape, and a downwardly extending portion provided continuously below the straight cylindrical portion 31. And a tapered cylindrical portion 32 having a progressively smaller diameter.

The lower end of the straight tubular portion 31 and the upper end of the tapered tubular portion 32 are connected by an integral flange portion 33. However, the straight tubular portion 31 and the tapered tubular portion 32 may be integrally formed. .

As shown in FIG. 2, the straight cylindrical portion 31
The liquid suction port 28 that is opened at the bottom is provided in the tangential direction of the straight cylindrical portion 31.

Also, as shown in FIG.
A bottomed cylindrical casing 36 having a suction port 34 and a discharge port 35 is fixed to the lower end of the tapered tubular section 32 of the tubular body 23, and inside the casing 36, gas-liquid mixing and stirring are performed. And a pump blade 37 for liquid supply is provided rotatably,
Further, a main shaft 38 penetrating through the cylinder 23 is connected to the center of the pump blade 37, and an electric motor 39 as a driving device for rotating the main shaft 38 is provided.
Are arranged above the cylindrical body 23.

The motor 39 has a motor main body 42 fixed to the upper side of the mounting plate 22 via a mounting base 41, and a motor rotating shaft 43 protruding from the motor main body 42 is connected to a main shaft 38 via a coupling 44.
It is connected to the.

The main shaft 38 has a bearing 45 provided on the mounting plate 22.
And a bearing portion 46 provided on a flange portion 33 between the straight tubular portion 31 and the tapered tubular portion 32, the bearing being rotatably supported by a bearing.For example, the lower end of the main shaft 38 is supported by a casing 36 of the pump 24. If the bearing can be supported or the length of the main shaft 38 is short, it is preferable that the intermediate bearing 46 is not provided.

In the intermediate portion, a through hole 47 as large as possible is provided in order to facilitate the flow of the liquid from the straight tubular portion 31 to the tapered tubular portion 32.

The discharge port 35 of the pump 24 is provided inside a plurality of discharge nozzles 48 protruding from the cylindrical peripheral surface of the casing 36. The discharge nozzles 48 may be arranged at regular intervals on the cylindrical peripheral surface of the casing 36, or may be arranged at irregular intervals depending on the installation environment such as the wall surface of the liquid tank 21.

The pump blade 37 disposed inside the casing 36 has a plurality of dish-shaped rotating blades 51 mounted on the main shaft 38 at a right angle, and at least facing the rotating blades 51 to the rotating blades 51.
Convex member as resistance increasing means for increasing surface resistance of 51
52 are provided.

The plurality of dish-shaped rotating blades 51 have a bent peripheral edge 53 bent obliquely downward, and the discharge nozzle 48 similarly projects obliquely downward.

As shown in FIG. 3, a convex member 52 as a resistance increasing means is provided at a bent peripheral portion 53 in a radial direction.

Next, the operation of the embodiment shown in FIGS. 1 to 3 will be described.

Due to the suction action of the pump 24, the liquid level of the liquid surface 56 in the straight tube portion 31 drops, and the liquid sucked into the straight tube portion 31 from the liquid suction port 28 causes the water to fall while entraining gas. As a result, the gas is efficiently sucked from the intake pipe 27 under the atmospheric pressure without using a conventional forced air supply device such as a compressor or a blower.

At this time, as shown in FIG.
Since the liquid is sucked into the straight cylindrical portion 31 from the tangential liquid suction port 28 and becomes a swirling flow inside the straight cylindrical portion 31, as shown in FIG. The gas is wound around the concave portion 57 at the center, and a large amount of gas can be efficiently sucked even under the atmospheric pressure (cyclone effect).

The liquid and the gas which flow into the straight tube portion 31 from the liquid suction port 28 as a waterfall are subjected to a mixing action in the straight tube portion 31 while passing through the through hole 47 from the straight tube portion 31.
Through the inside of the tapered tube portion 32,
A strong cyclone-like turbulent flow 58 is generated inside the gas turbine, so that the turbulent flow 58 efficiently agitates and mixes gas and liquid in the tapered tubular portion 32, and dissolves gas efficiently in the liquid.

The gas-liquid mixture processed in the tapered cylindrical portion 32 is sucked into the casing 36 from the suction port 34 of the pump 24, and is pumped by the pump blades 37 under pressure by the liquid pressure at the bottom of the liquid tank 21.
Since the gas is stirred and mixed while rotating, the gas is further dissolved in the liquid in the casing 36 at a high concentration.

At this time, a plurality of dish-shaped rotating blades 51 mounted at right angles to the main shaft 38 can rotate at a high speed, and the liquid is stirred and rotated by a convex member 52 therebetween so as to cut the liquid at a high speed. By generating fine turbulence on the surface of the wing 51 and efficiently generating countless fine bubbles, the gas dissolution ratio in the liquid is significantly increased.

The gas solution produced by the stirring and mixing by the pump blades 37 in the casing 36 and a large amount of microbubbles are supplied from a plurality of discharge nozzles 48 projecting from the cylindrical peripheral surface of the casing 36 to the liquid tank 21 around the pump. Dispersed and discharged over a wide range into the liquid inside.

At this time, the pump 24 transfers the gas-liquid mixture having a high gas dissolution ratio by centrifugal force generated by high-speed rotation and discharges the mixture into the liquid around the pump without deteriorating the performance.

The gas solution dispersed and discharged from each discharge nozzle 48 of the pump 24 is mixed with the liquid around the pump to increase the dissolved oxygen value of the liquid. Also, a large amount of fine bubbles 59
It floats from the pump area to the liquid level 25 in the tank.
The oxygen in the bubbles is dissolved in the contacted liquid.

The gas-liquid mixture directed obliquely downward by the centrifugal force applied from the convex member 52 of the bent peripheral portion 53 bent obliquely downward of the pump 24 once obliquely flows downward from the discharge nozzle 48. After being discharged to the surface of the liquid, the gas is turned into a floating state, so that the time required for the floating is increased, so that the gas is dissolved more effectively when floating in the liquid.

As described above, the gas dissolution by the gas-liquid stirring and mixing action in the cylinder 23 generated by the suction force of the pump 24
Gas dissolution by the gas-liquid stirring and mixing action in 24 and pump 24
By performing the gas dissolution processing in three stages of gas dissolution when the bubbles 59 discharged into the liquid in the liquid tank 21 from the liquid float in the liquid, high gas dissolution efficiency can be obtained.

Next, effects obtained by the present apparatus will be listed.

In the cylinder 23, the pump is driven by the rotation of the main shaft 38.
Due to the suction action of 24, the liquid level of the liquid level 56 in the straight tube portion 31 decreases, and the liquid becomes like a waterfall from the liquid suction port 28 opened in the straight tube portion 31 while entraining air. As it flows down, air can be efficiently sucked and mixed into the liquid under atmospheric pressure without using a compressor or a blower.

Further, inside the tapered tubular portion 32 of the tubular body 23, the liquid and the air that flow as a waterfall as a result of the rotation of the pump blade 37 due to the rotation of the main shaft 38 are removed.
A strong cyclone-like turbulent flow 58 is generated inside and the gas is passed while being stirred, so that the gas can be efficiently mixed and dissolved in the liquid.

In the pump 24, the gas and liquid are stirred and mixed while rotating under pressure, so that the gas can be dissolved in the liquid at a high concentration.

At this time, the pump 24 uses a plurality of specially shaped pump blades 37 to stir and mix the gas and liquid at a high speed, so that the liquid having a gas mixing ratio of 50% or more does not cause performance deterioration. Can be transferred, and a large amount of air can be injected into the liquid. In the ordinary pump 24, the mixing ratio of gas to liquid is limited to 5%.

Further, since the pump 24 merely increases the surface resistance of the dish-shaped rotary blade 51 mounted at right angles to the main shaft 38 by the convex member 52, clogging or contamination of the pump 24 due to sludge liquid or the like. Entanglement of the object can be prevented.

The pump 24 uses a high-speed rotation force of the pump blade 37 to discharge a gas-liquid mixture such as a gas solution and a large amount of fine bubbles 59 from a plurality of discharge nozzles 48 at a wide bottom in the liquid tank 21. It can be continuously dispersed and released in a range of liquids.

Since the gas solution is dispersed and mixed with the liquid in the liquid tank 21, the dissolved oxygen value of the liquid in the liquid tank 21, that is, the DО value can be increased. Also small bubbles 59
Rises up to the liquid level 25 while being in contact with the liquid in the liquid tank 21, and during this time, oxygen in the bubbles 59 moves to the liquid in the liquid tank 21, so that high oxygen dissolving efficiency can be obtained.

Further, only one motor 39 can efficiently perform the three-stage gas dissolving process. Further, the main shaft 38 penetrating the cylinder 23 allows the motor 39 to be placed above the liquid with respect to the pump blade 37 in the liquid. Since it is separated, maintenance of the electric motor 39 can be facilitated.

Next, another embodiment shown in FIGS. 4 to 6 will be described. The same parts as those in the embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 4, an electric motor 39 having a liquid-tight structure as a driving device of the pump 24 is integrally provided below the casing 36 of the pump 24.

On the side of the motor body 42 of the electric motor 39,
Legs 62 installed on the bottom surface 61 of the liquid tank 21 are integrally protruded downward, and a bearing 63
The mounting flange 64 is formed integrally with the motor main body 42, and is fixed to the bottom plate 65 of the casing 36 of the pump 24 via a packing 66 in a liquid-tight manner.

The main shaft 38 projecting upward from a bearing 63 provided at the center of the mounting flange 64 is connected to the center of the pump blade 37 through a shaft hole 67 formed in a bottom plate 65 of the casing 36. ing.

For this reason, as shown in FIG.
Does not have a main shaft 38 or the like, and there is nothing obstructing the swirling flow in the cylindrical body 23.

The pump blade 37 has a lower rotating blade 51 attached to the main shaft 38.
Are mounted at right angles, and above the rotor 51, upper rotors 51 are mounted in parallel via a plurality of coupling members 68 arranged as shown in FIG. A convex member 52 as a resistance increasing means for increasing the surface resistance of the rotary wing 51 is provided on the facing surface of the rotating blade 51.

The submerged motor-type gas-liquid mixing and dissolving apparatus can make the length and thickness of the main shaft 38 of the pump blade 37 constant irrespective of the depth of the liquid tank 21 (ie, the liquid depth). As a result, the structure related to the spindle can be greatly shortened and reduced in diameter.

That is, the main shaft 38 and the bearing 63 for suppressing the shaft runout vibration of the main shaft 38 can be downsized, the production cost of the main shaft 38 and the bearing 63 can be reduced, the manufacturing cost of the apparatus can be reduced, and Damage to the part 63 is reduced, and maintenance costs can be reduced.

Further, since it is not necessary to penetrate the main shaft 38 in the cylindrical body 23, when the gas is sucked and mixed into the liquid by the cyclone phenomenon in the cylindrical body 23, the main shaft 38 may be in the cylindrical body 23. As compared with the above, the cyclone phenomenon effect becomes more remarkable, and the gas suction amount due to the cyclone phenomenon effect increases.

As described above, in each embodiment, the process of mixing and dissolving air into the liquid is performed in three stages: inside the tapered tube portion 32 of the tube 23, inside the pump 24, and inside the liquid tank 21. As a result, high gas dissolving efficiency can be obtained, and the oxygen concentration in the liquid in the liquid tank 21 can be increased.

Further, the present apparatus is also used in the existing liquid tank 21.
Since it can be installed so as to be inserted from above the liquid tank 21, the initial cost can be reduced.

Further, the electric motor 39 can drive the pump 24 in the liquid under a light load state, and is capable of driving a gas into the liquid using a conventional forced air supply device such as a compressor or a blower.
The running cost required for driving the pump can be reduced, and the noise generated from the electric motor 39 and the like is quiet, and the noise can be reduced.

That is, since the hydraulic pressure corresponding to the submerged depth acts on both the suction side and the discharge side of the casing 36, the load of the pump 24 is hardly affected by the submerged depth.
The energy cost and noise of the electric motor 39 required for driving the pump 24 are lower than when gas is blown into the liquid using a forced air supply device such as a compressor or a blower.

The present apparatus is generally used in an aeration tank for water treatment for dissolving oxygen in air in water, but only gas or oxygen other than air is supplied from a suction pipe 27 to a cylindrical body.
By supplying the gas into the liquid 23, the gas can be dissolved in the liquid. Further, the present apparatus is not limited to being installed in the liquid tank 21, but includes a form used for a naturally formed liquid pool such as a pond.

[0066]

According to the first aspect of the present invention, gas dissolution by the gas-liquid stirring and mixing action in the cylinder caused by the suction force of the pump, gas dissolution by the gas-liquid stirring and mixing action in the pump, and High gas dissolution efficiency can be obtained by continuously performing the three-stage gas dissolution treatment with gas dissolution when bubbles discharged into the liquid float in the liquid.

According to the second aspect of the present invention, the liquid level in the straight cylindrical portion is reduced by the suction action of the pump,
The liquid sucked into the straight cylinder from the suction port flows down like a waterfall while entraining the gas, so the gas can be removed at atmospheric pressure without using a forced air supply device such as a conventional compressor or blower. Efficient suction can be performed, the cost of energy required for driving the pump can be reduced, and noise can be reduced.

According to the third aspect of the present invention, the liquid sucked from the liquid suction port in the tangential direction forms a swirling flow inside the straight cylindrical portion and flows down so that the central portion is depressed. The air can be efficiently wrapped in the concave portion of the portion, and can be efficiently sucked under the atmospheric pressure without using a forced air supply device.

According to the fourth aspect of the present invention, the liquid and the gas which flow into the straight cylindrical portion from the liquid suction port as a waterfall by the suction action of the pump are intensely cyclone-like inside the tapered cylindrical portion. Since the turbulent flow is generated, the gas-liquid can be efficiently stirred and mixed in the tapered cylindrical portion, and the gas dissolving efficiency can be improved.

According to the fifth aspect of the present invention, in the pump casing inserted into the liquid together with the cylinder, the gas and liquid are stirred and mixed while being rotated by the pump blades under pressure. The pump load is hardly affected by the depth of the liquid, and the pump load is hardly affected by the depth of the liquid. In contrast to the case where gas is blown into the liquid using the air supply device, the cost and noise of energy required for driving the pump can be reduced. Further, the three-stage gas dissolving process can be efficiently performed by only one driving device.

According to the sixth aspect of the present invention, the gas solution and a large amount of microbubbles generated by stirring and mixing by the pump blades in the casing are separated from the casing by a plurality of discharge nozzles projecting from the cylindrical peripheral surface of the casing. Dispersion can be continuously performed over a wide area around the device. The gas solution dispersed and discharged is mixed with the liquid around the pump to increase the dissolved oxygen value of the liquid,
While the small bubbles float to the liquid surface, the gas in the bubbles can be dissolved in the contacted liquid.

According to the seventh aspect of the present invention, the plurality of dish-shaped rotors mounted at right angles to the main shaft can rotate at a high speed, and the means for increasing the resistance between them allows the liquid to be cut at a high speed. By generating fine turbulence on the surface of the rotor blades by stirring to generate innumerable fine bubbles efficiently, the gas dissolution ratio in the liquid can be significantly increased and the gas dissolution ratio The high gas-liquid mixture can be transferred by centrifugal force due to high speed rotation and discharged into the liquid around the pump without deteriorating the performance. Further, since only the surface resistance of the dish-shaped rotor attached to the main shaft at right angles is increased by the resistance increasing means, clogging in the pump and entanglement of impurities can be prevented.

According to the eighth aspect of the present invention, the gas-liquid mixture directed obliquely downward by the centrifugal force applied from the radial resistance increasing means of the bent peripheral portion bent obliquely downward. Is discharged from a pump once obliquely downward, and then turns to float, so that the time required for floating is saved, and gas dissolved during floating in liquid can be more effectively dissolved.

According to the ninth aspect of the present invention, the present apparatus can be installed in an existing liquid tank so as to be inserted from the upper part of the liquid tank, and can be installed in the liquid tank by three-stage gas dissolution processing. The gas dissolving efficiency can be improved, and the cost and noise of energy required for driving the pump can be reduced as compared with the case where gas is blown into liquid using a conventional forced air supply device such as a compressor or a blower.

According to the tenth aspect of the present invention, since the driving device is provided integrally below the pump, the length and thickness of the main shaft of the pump blade can be greatly increased regardless of the depth of the liquid. The main shaft and the bearing structure for suppressing shaft run-out vibration of the main shaft can be made small and inexpensive because it can be made shorter and smaller in diameter, and when the gas is sucked and mixed into the liquid by the cyclone phenomenon in the cylinder, Since there is no need to penetrate the main shaft, which is an obstacle in the body, the cyclone effect is increased and the amount of gas suction by the cyclone effect can be increased.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a gas-liquid mixing and dissolving apparatus according to the present invention.

FIG. 2 is a sectional view of a liquid suction part of the gas-liquid mixing and dissolving apparatus.

FIG. 3 is a plan view of a pump blade of the gas-liquid mixing and dissolving apparatus.

FIG. 4 is a sectional view showing another embodiment of the gas-liquid mixing and dissolving apparatus according to the present invention.

FIG. 5 is a sectional view of a liquid suction portion of the gas-liquid mixing and dissolving apparatus.

FIG. 6 is a plan view of a pump blade of the gas-liquid mixing and dissolving apparatus.

FIG. 7 is a sectional view showing an example of a conventional gas-liquid mixing and dissolving apparatus.

[Explanation of symbols]

 21 Liquid tank 23 Cylinder 24 Pump 28 Liquid suction port 31 Straight cylinder 32 Tapered cylinder 36 Casing 37 Pump blade 38 Main shaft 39 Electric motor as drive unit 48 Discharge nozzle 51 Rotary blade 52 Convex member as resistance increasing means 53 Bend Perimeter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) F04D 29/22 F04D 29/22 B 29/44 29/44 D 31/00 31/00 F-term (reference) 3H022 AA01 AA06 BA01 BA04 3H033 AA07 AA20 BB01 BB06 BB12 BB16 BB17 CC01 CC03 DD03 EE19 3H034 AA07 AA20 BB01 BB06 BB12 BB16 BB17 CC01 CC03 DD12 EE18 4D029 AA09 AB02 4G035 AAAB

Claims (10)

[Claims] 1. A cylinder inserted into a liquid and sucking liquid and gas from above, and a pump provided at the lower part of the cylinder and sucking the liquid and gas inside the cylinder while stirring and mixing and discharging the liquid and gas to the surroundings. A gas-liquid mixing and dissolving apparatus characterized by the above-mentioned. 2. The cylinder according to claim 1, wherein the cylinder has a liquid suction port opened in the liquid, and has a straight cylindrical portion for causing the liquid sucked into the liquid suction port to fall in a waterfall shape. 2. The gas-liquid mixing and dissolving apparatus according to 1. 3. The gas-liquid mixing and dissolving apparatus according to claim 2, wherein the liquid suction port is provided in a tangential direction of the straight cylindrical portion. 4. The gas-liquid mixing and dissolving apparatus according to claim 2, wherein the cylindrical body has a tapered cylindrical portion provided at a lower portion of the straight cylindrical portion and having a gradually decreasing diameter toward the lower side. 5. A pump fixed to a lower end of a cylindrical body, a pump blade rotatably provided inside the casing, a main shaft connected to the center of the pump blade, and a drive for rotating the main shaft. The gas-liquid mixing and dissolving apparatus according to any one of claims 1 to 4, further comprising an apparatus. 6. The gas-liquid mixing and dissolving apparatus according to claim 5, wherein the casing is formed in a cylindrical shape and includes a plurality of discharge nozzles protruding from a cylindrical peripheral surface of the casing. 7. The pump blade includes a plurality of dish-shaped rotors mounted at right angles to the main shaft, and resistance increasing means provided on at least the opposing surfaces of the rotors to increase the surface resistance of the rotors. The gas-liquid mixing and dissolving apparatus according to claim 5 or 6, wherein: 8. A plurality of dish-shaped rotors having a bent peripheral edge bent obliquely downward, and a resistance increasing means provided radially on the bent peripheral edge. Item 7. A gas-liquid mixing / dissolving apparatus according to Item 7. 9. The gas-liquid mixing and dissolving apparatus according to claim 1, wherein the cylinder is fixed at an upper part of the liquid tank, and the pump is arranged near a bottom part of the liquid tank. . 10. The gas-liquid mixing and dissolving apparatus according to claim 5, wherein the driving device is integrally provided below the pump.