JPH08257383A - Gas-liquid dissolving and mixing apparatus - Google Patents

Abstract

PURPOSE: To easily separate excessive air while facilitating air treatment by simple constitution. CONSTITUTION: A liquid passage is branched into a plurality of parallel passages on the wag thereof and suction devices 6 each having a throttled part 30, an air inflow part 32, an air inflow port 40 and an expanded part 34 formed thereto are respectively provided to two or more passages among the branched passages 28. An air and liquid mixing part 8 is provided on the downstream side of the suction devices 6 and an upwardly protruding excessive air vent 10 and a passage are provided on the downstream side of the mixing part 8 and a flow rate regulating valve 21 is provided to the leading end of the passage of the excessive air vent 10 and a tank 18 is provided on the downstream side of this passage. Pipings 52, 54 discharging air are arranged to the tank 18 so as to be respectively shallowly and deeply inserted from above and the piping 52 deeply inserted in the tank 18 is connected to one of a plurality of air inflow ports 40 and the shallowly inserted piping 54 is connected to an exhaust pipeline 20 discharging excessive air to the outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-liquid dissolving / mixing apparatus for mixing and dispersing gas in a liquid or efficiently dissolving the gas in the liquid.

[0002]

2. Description of the Related Art A conventional gas-liquid dissolving and mixing apparatus is provided with a branched flow path which is branched upward, on the downstream side of a gas-liquid mixer, as disclosed in JP-A-6-269651, for example.
A gas-liquid mixing device has been proposed in which excess gas is allowed to escape upward. A flow rate control valve is provided at the tip of the surplus gas vent passage protruding above this, and its pipe is connected to an exhaust pipe line, and a predetermined process or the like is performed as necessary to exhaust the air.

[0003]

In the case of the above-mentioned conventional technique, it is impossible to reliably separate and discharge only the gas from the branched excess gas release passage, and a small amount of liquid is also discharged together with the exhausted gas. Had been discharged. However, it is very difficult to handle this mixed flow of gas and liquid, and when the exhaust gas is ozone, it cannot be released as it is to the outside air and must be treated when exhausted. Moreover, the ozone treatment device
Since the conventional excess gas venting channel is applied to a mixed flow of ozone and liquid because it dislikes water, it is not possible to directly attach the ozone treatment device to the exhaust pipe line.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a gas-liquid dissolving and mixing apparatus having a simple structure and capable of easily separating an excess gas. .

[0005]

SUMMARY OF THE INVENTION According to the present invention, a plurality of flow channels are branched in parallel on the way to a liquid flow channel, and a narrowed portion is formed in each of two or more flow channels of the plurality of parallel flow channels. A plurality of gas inflow portions each having a slightly larger inner diameter than each throttle portion and a constant cross-sectional area of a predetermined length, and a plurality of gases for sucking gas from the outside to each gas inflow portion. A structure having an inflow port and a widening part that expands the flow path toward the downstream side following each of the gas inflow parts, and joins again the plural parallel branched flow paths downstream of this widening part. In order to divide this flow path into a main flow path and a branch flow path downstream of the mixing section, the mixing section for mixing the gas and the liquid flowing in from the gas inlet is provided downstream of the suction section A surplus gas vent channel protruding above the A flow rate control valve is provided at the end of the surplus gas venting channel, and a tank with a structure that allows liquid to accumulate in the lower portion is provided downstream of the surplus gas venting channel, and a pipe for discharging gas is shallow from the top of this tank. Place one or more of each of the inserted one and the deeply inserted one, connect the pipe deeply inserted into the tank to one of the multiple gas inlets, and exhaust the extraly inserted pipe to the outside with the shallowly inserted pipe. It is a gas-liquid dissolving and mixing apparatus which is connected to a pipe and has a nozzle portion attached to a main flow channel downstream of a branch point of the surplus gas venting flow channel.

A mesh-like cover material containing sponge or mesh is attached to the inlet of the tank to which the surplus gas vent passage is connected and the bottom of the tank to prevent the liquid flowing in along with the surplus gas from scattering. It is what The suction device is integrally formed, and the plurality of branched flow paths are provided in parallel with each other. Further, between the suction device and the excess gas flow passage, there is provided a flow passage having a shape that gradually flows downward from the top. Also, an elongated pipe may be used instead of the flow rate control valve.

[0007]

In the gas-liquid dissolving and mixing apparatus of the present invention, the flow paths are branched in parallel, and the static pressure of the liquid in the flow paths is reduced by the throttle portion provided in the middle of the branched flow paths. A gas is made to flow in from a gas inflow part slightly downstream to form a gas-liquid mixed flow. Then, in the downstream mixing section, the flow is slowed to increase the static pressure again, and the inflowing gas and liquid are dissolved under pressure,
The excess gas that could not be dissolved in the mixing section is branched upward in the excess gas release channel after the mixing section. On the other hand, the liquid flowing through the main flow path is accelerated when passing through the nozzle portion and the static pressure becomes low again, and the gas dissolved from the liquid is deposited as fine bubbles. In addition, the gas and a small amount of liquid flow into the surplus gas vent passage branched upward, and flow into the tank through the flow rate control valve. In this tank, the structure is such that the liquid accumulates downward, and the gas and the liquid that have flowed in from the surplus gas removal channel are separated, and the liquid accumulates downward. From the pipe that is deeply inserted in the tank,
The liquid and a small amount of gas flow out to the gas suction port of the suction device, and are mixed with the gas-liquid mixed flow again. On the other hand, only the excess gas is discharged from the pipe that is shallowly inserted into the tank.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the gas-liquid dissolving and mixing apparatus of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment of the present invention. In a gas-liquid dissolving and mixing apparatus of this embodiment, a water tank 2 which is a liquid supply section and a pump 4 for pumping a liquid are connected by a pipe 3. There is. A suction device 6 is connected to the discharge side of the pump 4 via a pipe 5. A pipe 8 also serving as a mixing portion is connected to the downstream side of the aspirator 6 in a meandering state, and a surplus gas vent 10 that divides the flow passage into a main flow passage and a branched flow passage is provided at the downstream end of the pipe 8. It is connected. A pipe 13 having a nozzle portion 12 provided on the way is connected to the main flow path side from the surplus gas vent 10. The tip of the pipe 13 provided with the nozzle portion 12 is connected to the vicinity of the bottom of the foaming liquid tank 14 and opens.

As shown in FIG. 2, the suction device 6 is integrally formed in a cylindrical shape, and has a branch point 26 inside the liquid inflow portion 24 side.
The liquid flow paths parallel to each other are branched into two. In addition,
In the aspirator 6 of this example, the bifurcation is performed at the branch point 26, but it may be branched into three or more flow paths. In each of the flow paths after branching, a venturi-shaped flow path 28 having a throat portion 30 forming a narrowed portion provided in the center is formed. Downstream of the throat portion 30, a gas inflow portion 32 having a cylindrical shape in the flow direction is provided.
Is provided, and a gas inlet 40 communicating with the side of the suction device 6 is vertically formed in the gas inflow portion 32.
Then, the branched flow paths 28 merge after the gas inflow portion 32, through the respective widening portions 34, at a confluence point 36, and continue to the liquid outflow portion 38 of the aspirator 6. The gas pipeline 7 is connected to one gas inlet 40 of the suction device 6, and the gas pipeline 7 is connected to the gas pipeline 7.
Is connected to a gas supply source 9 such as a cylinder for supplying a gas such as ozone to be mixed.

As shown in FIG. 3, the excess gas venting 10 is
Inside the surplus gas vent 10, a channel 48 protruding upward is formed between the inlet 42 and the main channel side outlet 44. A surplus gas outlet 46 is attached to the tip of the flow path 48.

In the excess gas vent 10, the flow path 48 on the branched side is connected to the tank 18 via the flow rate adjusting valve 16 and the pipe 17, and the pipe 18 and the exhaust pipe 20 are connected from the tank 18. It is connected. A pressure adjusting valve 21 for adjusting the pressure inside the tank 18 is attached in the middle of the exhaust pipe 20, and the ozone treatment device 2 is provided on the downstream side thereof.
3 is attached.

As shown in FIG. 4, the tank 18 includes a gas-liquid mixture inlet pipe 50 and a pipe 5 into which a tip portion is deeply inserted.
2. A pipe 54 having a shallow tip is provided, and a sponge 56 is attached to the bottom of the tank 18.
A cylindrical sponge 58 is also attached to the tip of the gas-liquid mixture inlet pipe 50. Gas-liquid mixture inlet pipe 50
Is connected to the pipe 17 from the excess gas vent 10, and the pipe 5
A pipe 22 connected to the suction device 6 is connected to 2. Further, the exhaust pipe 20 is connected to the pipe 54.

Next, the operation of the gas-liquid dissolving and mixing apparatus of this embodiment will be described below. The liquid in the aquarium 2 is pump 4
Is sent under pressure to the suction device 6 and flows into the liquid inflow portion 24 of the suction device 6. The inflowing liquid is branched into two flow passages at a branch point 26, is accelerated in the throat portion 30 of the Venturi pipe in each flow passage 28, and the static pressure is once reduced, and the cylindrical gas inflow portion 3
At 2, the gas flows in and is mixed, and the static pressure increases again through the spreading portion 34. After passing through the widening portion 34, the gas-liquid mixed flow merges again into one at the merging point of the branched flow paths. At this time, since the gas inlet 40 is slightly downstream of the throat 30 and the cross-sectional area of the gas inlet 32 is also slightly larger than that of the throat 30, the static pressure of this portion is relatively low, Gas flows into the flow path. This gas inlet 40
The throat portion 30 is not provided in the throat portion 30 where the static pressure is the lowest, but if the throat portion 30 is provided with a gas inlet,
This is because the suction of gas is not good.

The gas flowing in from the gas inlet 40 becomes bubbles together with the liquid in the flow path through the outlet 38 of the aspirator 6 and flows into the pipe 8 which also serves as a mixing portion. Since the static pressure of the pipe 8 is higher than that of the gas inflow portion 32, the gas that has become bubbles dissolves in the liquid. Then, the liquid is removed from the gas which has not been completely dissolved in the liquid by the excess gas release 10 from the pipe 8. On the other hand, when the liquid flowing through the main flow path passes through the nozzle portion 12, the liquid is accelerated again, so that the static pressure becomes low and the gas dissolved in the liquid is deposited as fine bubbles. The liquid flowing through the main flow channel is the liquid to be foamed tank 1
It is ejected together with the bubbles that have precipitated in 4.

In the gas-liquid dissolving and mixing apparatus of this embodiment, the sum of the cross-sectional area of the throat portion 30, the gas inflow portion 32, the cross-sectional area of the throttle of the nozzle portion 12 and the throat portion 30 in each flow path.
The relation of the total sum of the cross-sectional areas of the above may be any as long as the following formula is satisfied. PAn = PGn (1) PGn is the pressure of the gas flowing from the gas inlet 40 (n is a natural number and corresponds to each gas inlet). PAn is the static pressure of the gas inflow part 32 given by the following equation according to the continuity equation in fluid dynamics and Bernoulli's theorem. ^{PAn = {1- (SAn 2 SC} 2) / (SA 2 SBn 2)} P1 + (δP + PB) {(SAn 2 SC 2) / (SA 2 SBn 2)} (2) where, SA throat section 30 Of cross-sectional area of S, SAn is throat 3
0, the cross-sectional area of SBn is the cross-sectional area of the gas inflow portion 32, SC is the total cross-sectional area of the throttle of the nozzle portion 12, and P1 is the gas inflow portion 3
2 is the total pressure, δP is the pressure loss from the suction device 6 to the nozzle portion 12, and PB is the static pressure at the outlet of the nozzle portion 12.

Therefore, by setting the sizes of the throttles of the gas inflow portion 32 and the nozzle portion 12 so as to satisfy the above equations (1) and (2), it is optimal to efficiently mix and dissolve them in the liquid. It is possible to obtain various conditions. Also,
It is more preferable that the pipe 8 also serving as the mixing section is one that can obtain the gas-liquid contact time until the gas is dissolved and saturated in the liquid under pressure, and the gas-liquid contact time depends on the volume of the pipe. , The gas dissolves up to the saturation point when the length of the pipe is longer to some extent. If it is not necessary to dissolve the gas to the saturation point, the pipe 8 may be short. Further, the shape of the pipe 8 can be arbitrarily set, such as a meandering shape, a spiral shape or a coil shape.

The excess gas outlet 4 for removing the excess gas 10
From 6, a gas-liquid mixed flow consisting of a gas containing a small amount of liquid flows out. This is because it is impossible to separate only the excess gas, and the total amount of the excess gas and a small amount of liquid in the gas-liquid mixed flow are separated. The gas-liquid mixed flow leaving the surplus gas outlet 46 flows into the tank 18 through the flow rate control valve 16 and the pipes 17 and 50. The flow rate control valve 16 is adjusted so that an appropriate amount of gas-liquid mixed flow flows out.

The gas-liquid mixed flow that has flowed into the tank 18 is separated into a gas layer and a liquid layer because the structure of the tank 18 allows liquid to be accumulated below. At this time, sponges 56 and 58 are attached to the gas-liquid mixture inlet pipe 50 and the lower part of the tank so that the water droplets of the gas-liquid mixed flow that have flowed into the tank 18 do not scatter and enter the exhaust pipe 20 from the pipe 54. is there. The sponge 58 may be a mesh having a sufficiently fine mesh capable of preventing water droplets from scattering, and any sponge or mesh-like cover material including the mesh may be used. Note that the sponge may be appropriately omitted when water droplets may be scattered. Then, the liquid and a small amount of gas accumulated below the tank are discharged from the pipe 52 that is deeply inserted into the tank 18, and the liquid and the small amount of gas are one of the plurality of gas inlets 40 of the aspirator 6. It is sucked by the suction device 6 through the pipe 22 connected to. Further, only the gas is exhausted from the pipe 54 through the exhaust pipe 20. The pressure in the tank 18 can be adjusted by the pressure adjusting valve 21. If the pressure adjustment in the tank 18 is unnecessary, the pressure adjustment valve 21 may be omitted as appropriate. Further, when the excess gas may be released under the atmospheric pressure, the exhaust pipe 20 may be opened under the atmospheric pressure without providing a device such as the ozone processing device 23.

According to the gas-liquid dissolving and mixing apparatus of this embodiment,
When the gas is ozone, the exhaust pipe 20 is connected to the ozone treatment device 2
By connecting to 3, the ozone in the excess gas can be surely treated, the liquid is not mixed in the exhaust pipe 20, and it is safe and has no adverse effect by the liquid.

Next, a gas-liquid dissolving and mixing apparatus according to the second embodiment of the present invention will be described with reference to FIGS. here,
The same members as those in the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, instead of the pipe 8 which also serves as the mixing portion of the first embodiment, a gas-liquid mixing tank 60 is provided as a mixing portion, in which a flow path 66 is formed in which the flow is gradually and repeatedly repeated. Therefore, the suction device 6 is attached on the upstream side of the gas-liquid mixing tank 60, and the excess gas vent 10 and the nozzle portion 12 are provided on the downstream side of the mixing tank 60.

The gas-liquid mixing tank 60 has a flow path 66 that gradually and gradually drops and flows downward. When a gas-liquid mixed flow is flown through this flow path 66, gas is generated in the upper portion and liquid is generated in the lower portion in the flow path 66. It becomes a flowing state, and a gas-liquid mixed flow having a wide contact area of gas-liquid can be obtained. Further, since the position of the outlet 64 is lower than the position of the inlet 62 of the gas-liquid mixed flow, the gas with low density becomes stagnant in the flow path 66, and the ratio of the gas of the gas-liquid mixed flow is relatively large at the inflow stage. Even if it is low, the gas ratio inside the mixing tank 60 is high. Therefore, highly efficient gas dissolution is performed inside the gas-liquid mixing tank 60.

Next, a gas-liquid dissolving and mixing apparatus according to the third embodiment of the present invention will be described with reference to FIG. Here, the same members as those in the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, instead of the valve 16 of the first embodiment, a pipe 68 having a small inner diameter is used. In this case, the proper adjustment of the flow rate is performed by changing the length of the pipe. Actually, in the experiment, 7m pipe with 3mm inner diameter
Showed the same effect as the flow control valve. By using the pipe 68 of this embodiment, since the minimum flow path width can be made large, the structure is resistant to the clogging of the pipe. Further, in this embodiment, the pipe is wound into a coil,
Any shape may be used as long as a predetermined pipe length can be obtained.

[0023]

According to the gas-liquid dissolving and mixing apparatus of the present invention,
Even if some liquid is mixed with the excess gas branched by removing the excess gas, only the gas can be reliably separated and discharged in the tank. In particular, when handling a gas that needs to be exhausted, the gas is not mixed into the exhaust, the device is easy to handle, and the gas can be reliably processed.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a gas-liquid dissolving and mixing apparatus according to a first embodiment of the present invention.

FIG. 2 is a front view (A) and a vertical sectional view (B) of an aspirator of a gas-liquid dissolving and mixing apparatus according to the first embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view of the gas-liquid dissolving and mixing apparatus according to the first embodiment of the present invention with excess gas removed.

FIG. 4 is a vertical cross-sectional view of the tank of the gas-liquid dissolving and mixing apparatus according to the first embodiment of the present invention.

FIG. 5 is a schematic view showing a gas-liquid dissolving / mixing apparatus according to a second embodiment of the present invention.

FIG. 6 is a vertical cross-sectional view of a mixing tank of a gas-liquid dissolution mixing device according to a second embodiment of the present invention.

FIG. 7 is a schematic view showing a gas-liquid dissolving / mixing device of a third embodiment of the present invention.

[Explanation of symbols]

 6 Suction device 8 Piping (mixing part) 10 Excess gas removal 12 Nozzle part 16 Flow rate control valve 18 Tank

Claims (5)

[Claims] 1. A branch point at which a plurality of flow channels are branched in parallel in the liquid flow channel, a throttle portion formed in each of two or more flow channels of the plurality of parallel flow channels, and each throttle. A plurality of gas inlets each having a slightly larger inner diameter than each throttle portion and a constant cross-sectional area for a predetermined length, and a plurality of gas inlets for sucking gas from the outside to each gas inlet, An aspirator provided with a widening portion in which the flow passage is widened toward the downstream side following each gas inflow portion, and a confluence point where the flow passages that have been branched in parallel are joined again downstream of the widening portion. Provided downstream of the aspirator, a mixing section for mixing the gas and the liquid flowing in from the gas inlet, and projecting upward to divide the flow path into a main flow path and a branch flow path, downstream of the mixing section. The excess gas release channel is provided to allow the excess gas release channel to protrude upward. A flow rate control valve was installed first, and a tank with a structure for collecting liquid below was installed downstream of this excess gas release channel, and a pipe for discharging gas was inserted deeply into this tank, with a pipe inserted shallowly from above. However, one or more of each of them is arranged, the pipe deeply inserted into the tank is connected to one of the plurality of gas inlets, and the shallowly inserted pipe is connected to an exhaust pipe for discharging the surplus gas to the outside, A gas-liquid dissolving and mixing device having a nozzle portion in a main flow path downstream of a branch point of the surplus gas venting flow path. 2. A mesh-like cover material for preventing scattering of a liquid flowing in together with the surplus gas is attached to at least one of an inlet portion of the tank to which the surplus gas vent passage is connected and a bottom portion of the tank. The gas-liquid dissolution mixing device according to claim 1. 3. The gas-liquid dissolving and mixing apparatus according to claim 1, wherein the suction device is integrally formed, and the plurality of branched flow paths are provided in parallel with each other. 4. The gas-liquid dissolving / mixing apparatus according to claim 1, wherein a flow passage having a shape that gradually flows downward is provided between the suction device and the flow passage for the excess gas. 5. The gas-liquid dissolving and mixing apparatus according to claim 1, wherein an elongated pipe is provided in place of the flow rate control valve downstream of the surplus gas vent channel, and the pipe is connected to the tank.