JP5296565B2 - Stirrer - Google Patents

Description

  The present invention relates to a stirrer provided with an air lift pump, and more particularly to a stirrer that is optimal for stirring the waste water in a building drainage tank.

  The building drainage tank is installed in the basement of the building to temporarily store sewage generated in the building and drain it into the sewer. In this building drainage tank, sludge and organic matter contained in the sewage rot and generate malodorous substances such as methyl mercabtan and hydrogen sulfide. In order to prevent this harmful effect, the Tokyo Metropolitan Government has been implementing the “Guidelines on the Structure and Maintenance of Drainage Tanks in Buildings (Billpit Countermeasure Guidance Guidelines)”. Based on these guidelines, devices have been developed to prevent the odor of sewage. As a stirring device used for this purpose, a device that rotates a screw with a submersible motor, sucks sewage from above, and injects it in a horizontal direction is used. Further, in order to aerate and replenish oxygen in the sewage, this apparatus supplies pressurized air to the screw portion and agitates and blows out the air and sewage. Since this agitator uses a submersible motor, there are disadvantages that the equipment cost is high, the service life is short, and the power consumption is large, so that the running cost is also high.

  An apparatus for aeration while stirring sewage has been developed (see Patent Document 1). As shown in FIG. 1, the apparatus described in this publication raises and stirs the liquid with the rising force of the bubbles while injecting the bubbles into the water and aeration, thereby reducing the equipment cost as a simple structure. .

JP-A-8-103790

  However, the stirrer shown in FIG. 1 has a drawback that the liquid cannot be stirred efficiently. In particular, in a state where the liquid level of the stirring tank fluctuates, there is a drawback that the liquid stored in the stirring tank cannot be stirred efficiently and it is difficult to aerate effectively.

The present invention has been developed for the purpose of solving the above-mentioned drawbacks. An important object of the present invention is to provide an agitation device provided with an air lift pump that can aeration while efficiently agitating a liquid even when the liquid level changes, while significantly reducing equipment costs and running costs.
Another important object of the present invention is to provide a stirring device that has a simple structure, has no failure portion, is durable, and can reduce failure.

Means for Solving the Problems and Effects of the Invention

  The stirring device of the present invention includes a stirring tank 1 that stores a predetermined amount of liquid, and an air lift pump 2 that sucks the liquid in the stirring tank 1 from the bottom, discharges it to the top, and stirs it. The air lift pump 2 is disposed in the agitation tank 1 so as to extend from the bottom to the liquid level, and has a rising pipe 3 having a suction port 7 at the bottom and a discharge port 6 at the top. And an air pump 4 for supplying air to the bottom. In the air lift pump 2, a plurality of discharge ports 6 are branched between the upper end and the bottom of the ascending pipe 3, and the discharge ports 6 are changed depending on the water depth of the stirring tank 1.

  The agitator described above has the feature that it can aerate while stirring the liquid efficiently even if the liquid level changes, while significantly reducing the equipment cost and running cost. This is because the above stirring device is provided with a plurality of discharge ports between the bottom and the upper end of the riser. The riser pipe provided with a plurality of discharge ports is the discharge port at the same level as the liquid level even if the liquid level changes, or is lower than the liquid level and closest to the liquid level This is because the liquid is discharged from the discharge port. That is, the liquid is discharged from the discharge port opened at the top closest to the liquid level and is not discharged from the intermediate discharge port below the discharge port. Is inhaled and discharged from the outlet near the liquid level. That is, the stirring device of the present invention is provided with a plurality of discharge ports in the riser pipe of the air lift pump, but it is variable without providing a mechanism for detecting the liquid level and selecting the discharge port for discharging the liquid. The liquid can be efficiently stirred with the riser pipe by discharging from the uppermost discharge port closest to the liquid level, which is optimum for the liquid level. The air lift pump can increase the liquid transfer efficiency by increasing the lift from the bottom portion for sucking the liquid to the discharge port. The above ascending pipe is provided with a plurality of discharge ports and has a simple structure that does not include a mechanism for specifying a discharge port for discharging liquid, but the discharge port for discharging liquid is most at the liquid level. The closest top one is automatically selected. For this reason, even if the liquid level changes, the discharge port is automatically selected so as to always have the highest head, and the riser can efficiently raise and stir the liquid. The ascending pipe that transfers the liquid in the state where the lift is the highest with respect to the fluctuating liquid level, sucks the liquid from the bottom of the stirring tank and discharges it in the horizontal direction in the vicinity of the liquid level. As shown in FIG. 4, the liquid is forced to stir by flowing in a convection manner inside the stirring tank. In addition, the liquid inside the ascending pipe is raised with a substantially reduced specific gravity by the supplied bubbles, so that it does not rise together with the bubbles, and the bubbles rise faster than the liquid. Thus, the bubbles and the liquid can move relative to each other for efficient aeration. Further, since the discharge port is selected so as to achieve a high head, the bubbles rising up the riser are in contact with the liquid for the longest with respect to the changing liquid level and are efficiently aerated.

  Furthermore, the above stirring device does not require complicated parts such as submersible motors and screws, and is a simple cylinder, so it has an extremely simple structure, no faults, durability, and easy maintenance. Features that can be realized.

  Furthermore, the agitator described above does not require the use of a large blower or the like for aeration, and realizes a feature that the power consumption can be reduced and the noise level can be extremely reduced. In addition, the above stirring device can be aerated while efficiently stirring the liquid in the stirring tank with a simple riser pipe and an air pump that supplies air to the rising pipe. However, it can be operated economically and with less energy consumption. Incidentally, according to the experiment of the present inventor, when the liquid in the agitation tank having a water depth of about 1 meter was agitated by the agitator of the present invention and the submersible pump, the agitator of the present invention was comparable to a 400 W submersible pump. It was possible to realize the flow rate to be achieved with an air pump composed of a diaphragm pump of only 50 W. Furthermore, since the stirring device of the present invention forcibly stirs by injecting air to the bottom of the ascending pipe, a feature that enables efficient aeration simultaneously with stirring is also realized.

In the stirring device of the present invention, the discharge port 6 has a branch pipe 8 that is bent or bent in the horizontal direction from the vertical direction, and the discharge port 6 arranged above and below is the same with this branch pipe 8. It opens to face the direction.
In the above stirring device, the liquid transferred upward by the ascending pipe is smoothly changed in the horizontal direction by the branch pipe and discharged in the horizontal direction, so that the liquid sucked from the bottom of the stirring tank is forced in the horizontal direction. The entire liquid can be efficiently stirred by flowing it.

In the stirring device of the present invention, the discharge ports 6 can be opened on both sides of the ascending pipe 3.
The above stirring device discharges the sucked liquid to both sides of the ascending pipe, so that the ascending pipe can be disposed in the middle of the stirring tank and the liquid can be efficiently stirred on both sides.

The stirring device of the present invention is connected to an injector 12 that injects a liquid, powder, gas, or a mixture to be mixed at the bottom of the riser 3 and is supplied from the injector 12. The mixture to be mixed can be mixed with the liquid rising inside the ascending pipe 3.
The above stirring apparatus can efficiently stir the mixture to be supplied here while raising the liquid with the rising pipe. That is, both stirring and mixing can be realized with a simple structure.

The stirring device of the present invention can connect the injector 12 in the middle of the air pipe 5 formed by connecting the air pump 4 and the rising pipe 3.
The above stirrer has a simple structure by sucking the mixture into the air pipe using the ejector effect of the air that flows at high speed through the air pipe and then injecting the mixture from the air pipe into the riser pipe. There is a feature that the mixture can be efficiently supplied to the riser and mixed uniformly.

In the stirring apparatus of the present invention, the injector 12 can include a supply pump 13 for supplying a liquid mixture.
This stirrer supplies the liquid mixture to the ascending pipe with a supply pump, so that the mixture and the liquid can be evenly distributed while controlling the mixing ratio of the mixture to be sure and stable. Can be mixed efficiently.

The agitation apparatus of the present invention can agitate the wastewater from the building drainage tank 21 with the air lift pump 2 using the agitation tank 1 as the building drainage tank 21.
The above agitator has a feature that it can be aerated while efficiently agitating sewage in a building drainage tank. In addition, the structure is simple and does not require maintenance, and the power consumption can be reduced. Thus, a feature that enables aeration while forcibly stirring the building drainage tank is realized.

  In the stirring device of the present invention, the air pump 4 can be a diaphragm pump. Since this stirring device uses a diaphragm pump having a simple structure as an air pump, it has a feature that it is durable and can be made inexpensive.

  Furthermore, the stirring device of the present invention can close or open the upper end of the riser 3.

It is sectional drawing of the conventional stirring apparatus. It is the schematic which shows the usage example of the stirring apparatus concerning one Example of this invention. It is a schematic block diagram of the stirring apparatus concerning one Example of this invention. It is an expanded sectional view of the air lift pump shown in FIG. It is a schematic block diagram of the stirring apparatus concerning the other Example of this invention. It is an expanded sectional view of the air lift pump shown in FIG. It is an expanded sectional view showing other examples of an air lift pump. It is an expanded sectional view showing other examples of an air lift pump. It is an expanded sectional view showing other examples of an air lift pump. It is an expanded sectional view showing other examples of an air lift pump. It is an expanded sectional view showing other examples of an air lift pump.

  Embodiments of the present invention will be described below with reference to the drawings. However, the Example shown below illustrates the stirring apparatus for actualizing the technical idea of this invention, Comprising: This invention does not specify a stirring apparatus to the following.

  Further, in this specification, in order to facilitate understanding of the scope of claims, numbers corresponding to the members shown in the examples are indicated in the “claims” and “means for solving problems” sections. It is added to the members. However, the members shown in the claims are not limited to the members in the embodiments.

  2 and 3 show a specific example in which the stirring device is used in a device for stirring and aeration of sewage in a building drainage tank 21. FIG. This agitator uses the agitation tank 1 as a building drainage tank 21 to agitate and aerate the sewage in the bill pit 20. The building drainage tank 21 which is the building pit 20 prevents sludge accumulation by agitating the sewage with a stirrer, and further aerated to replenish oxygen to the sewage and decompose organic matter by the action of aerobic microorganisms. This prevents the generation of malodorous components such as hydrogen sulfide and methyl mercaptan. Malodorous components such as hydrogen sulfide generated in the building pit 20 leak from the manhole 22 and cause bad odor. Further, when this is drained into the sewer 30, the sewer 30 is corroded. If the sewer 30 is corroded and perforated, a serious problem such as a road sinking occurs. For this reason, it is important for the sewage in the building pit 20 to prevent generation of malodorous components such as hydrogen sulfide.

  As shown in FIG. 2, the building drainage tank 21 drains the sewage stored here from the public basin 24 to the sewer 30 with the drainage pump 23. Since the building drainage tank 21 is supplied with building sewage, the liquid level varies. Therefore, it is important for the building drainage tank 21 to efficiently agitate and aerate the sewage even if the liquid level changes. The agitation tank 1 in FIG. 3 includes an air lift pump 2 including a riser pipe 3 provided in the agitation tank 1 of the building drainage tank 21 and an air pump 4 that supplies air to the riser pipe 3.

  As shown in FIGS. 3 and 4, the air lift pump 2 includes a rising pipe 3 disposed so as to extend from the bottom of the agitation tank 1 to the level of the sewage liquid, and a bottom of the rising pipe 3. And an air pump 4 for supplying air. The air lift pump 2 supplies air to the bottom of the ascending pipe 3 with the air pump 4. The ascending pipe 3 to which air is supplied raises the liquid by reducing the specific gravity of the liquid by countless bubbles mixed with the liquid. The sewage is lifted up the ascending pipe 3 and forcibly stirred inside the building drainage tank 21 which is the stirring tank 1. Furthermore, the sewage is aerated by contacting countless bubbles in an agitated state, and oxygen is replenished.

  The ascending pipe 3 is a pipe that is open at both upper and lower ends, and is arranged vertically. The ascending pipe 3 can raise and stir the sewage most efficiently in a vertical posture. However, since the rising pipe can be arranged to be inclined to raise the sewage, it is not always necessary to arrange the rising pipe in a vertical posture. The ascending pipe separates the lower end from the bottom surface of the stirring tank and sucks the liquid at the bottom of the stirring tank.

  The ascending pipe 3 shown in FIGS. 3 and 4 has a structure in which the lower part is connected to the bottom plate 10 via the connecting arm 11 so that it can stand upright in a vertical posture. The bottom plate 10 is a metal plate, and has a size and a weight that allow the riser 3 to stand by itself inside the stirring tank 1. The bottom plate 10 has a size that can pass through the manhole 22 of the building drainage tank 21. The air lift pump 2 has a feature that it can be easily installed by being inserted into the building drainage tank 21 from the manhole 22. However, since the use of the stirrer of the present invention is not specified for sewage agitation and aeration in a building drainage tank, the size of the bottom plate can be optimized for each use. The ascending pipe 3 is disposed away from the upper surface of the bottom plate 10 via the connecting arm 11, and the lower end is opened as the suction port 7.

  The ascending pipe 3 is provided with a plurality of outlets 6 branched between an upper end and a bottom, and the outlet 6 to be discharged is automatically changed depending on the water depth of the stirring tank 1. The ascending pipe 3 shown in the figure is provided with three discharge ports 6 at the upper end and in the middle. However, the ascending pipe can be provided with two discharge ports or four or more discharge ports. In particular, the riser pipe used in the stirring tank in which the liquid level changes greatly can efficiently stir by increasing the number of discharge ports and discharging the liquid in the vicinity of the liquid level.

  The discharge port 6 has a shape that curves in the horizontal direction from the vertical direction. The discharge port 6 smoothly discharges sewage discharged to the liquid surface from the vertical direction to the horizontal direction. For this reason, sewage can be efficiently discharged in the horizontal direction. The discharge port 6 having this structure can be realized by using “90 ° large bend Y” used for a drain pipe joint in the middle of the ascending pipe 3. The drain pipe joint connects the branch pipes 8 so as to bend with a predetermined radius of curvature so that the discharge flows smoothly. The ascending pipe 3 in FIGS. 3 and 4 is opened toward one side so that the plurality of discharge ports 6 face the same direction. The ascending pipe 3 discharges the liquid sucked from the bottom to one side of the ascending pipe 3. As shown in FIG. 2, the rising pipe 3 is installed on one side of a building drainage tank 21 that is a stirring tank 1, and injects sewage to be sucked toward the center to uniformly stir the whole.

  The ascending pipe 3 shown in FIGS. 5 and 6 is provided with a pair of discharge ports 6 for discharging liquid sewage in different directions, in the drawings, in opposite directions. The ascending pipe 3 has a shape in which each discharge port 6 is curved in the horizontal direction toward opposite sides. The ascending pipe 3 stirs the discharged liquid sewage in the horizontal direction in opposite directions. The ascending pipe 3 is installed in the central portion of the stirring tank 1 to efficiently stir the entire liquid.

  The ascending pipe 3 of FIGS. 3 to 6 has an upper end opened as an air vent 9. The rising pipe 3 discharges the rising liquid together with the air from the discharge port 6 in the horizontal direction while exhausting the rising air at the air vent 9. 7 and FIG. 8, the upper end is curved from the vertical direction to the horizontal direction, and the discharge port 6 is opened in the horizontal direction. The ascending pipe 3 discharges both air and liquid from the upper discharge port 6. The ascending pipe 3 can efficiently agitate the liquid by disposing the upper discharge port 6 at the liquid level. This is because air and liquid are discharged in the same direction, and the liquid can be discharged efficiently and the discharge flow rate can be increased.

  FIGS. 4 and 6 show a state in which the rising pipe 3 having a plurality of discharge ports 6 at the upper end and the middle sucks and discharges liquid sewage. 4 and 6 show a state in which the liquid level is in the vicinity of the upper discharge port 6 by a solid line. In this state, the ascending pipe 3 discharges the sewage of the liquid to be sucked from the discharge port 6 at the upper end. The middle discharge port 6 hardly discharges sewage of the liquid to be sucked. This is because the pressure of the liquid decreases as the flow velocity increases, and the internal pressure decreases as the liquid rises inside the ascending pipe 3. When the internal pressure of the ascending pipe 3 decreases, liquid is sucked from the intermediate discharge port 6. However, since the internal pressure of the ascending pipe 3 varies depending on the flow velocity, the decrease in the internal pressure when the flow velocity is low is small, and the intermediate discharge port 6 in the liquid may slightly discharge the liquid sucked from the bottom. . However, the discharge amount is small, and the ascending pipe 3 discharges most of the liquid sucked from the bottom to the liquid level, and efficiently and forcibly stirs the liquid in the stirring tank 1.

  When the liquid level becomes low, as indicated by a chain line A in FIGS. 4 and 6, the liquid is discharged from the intermediate discharge port 6 located at the liquid level. This is because the raised liquid flows out smoothly from the discharge port 6 at the liquid level, rather than being lifted up to the discharge port 6 at the upper end. However, if the height difference between the upper end and the middle discharge port 6 is small and the flow rate of the liquid rising up the ascending pipe 3 is fast, liquid may be discharged from the discharge port 6 above the liquid level. . In this state, the discharge port 6 in the liquid is in the same state as the solid line in FIG. 4 and FIG. 6, and slightly inhales or discharges the liquid, or hardly inhales or discharges. Therefore, the riser 3 discharges the liquid sucked from the bottom of the stirring tank 1 to the liquid level and stirs.

  The ascending pipe 3 is connected to an air pump 4 via an air pipe 5 at the bottom. The pressurized air supplied from the air pump 4 is supplied to the ascending pipe 3 through the air pipe 5. The air supplied to the ascending pipe 3 becomes innumerable bubbles and is injected into the ascending pipe 3 to increase the specific gravity of the liquid in the ascending pipe 3 with a reduced specific gravity. The air pump 4 is a pump that can supply pressurized air to the bottom of the ascending pipe 3, and a diaphragm pump is used. The air pump 4 pressurizes and supplies air to a high pressure at the bottom of the ascending pipe 3. Since the water depth is 1 m and the water pressure is 10 kPa, the agitation tank 1 having a maximum water depth of 1 m can supply liquid having a pressure higher than 10 kPa to the ascending pipe 3 to raise the liquid to the ascending pipe 3. For example, a diaphragm pump with a power consumption of 50 W has a discharge pressure of 11 kPa and an air flow rate of about 50 liters / minute. Therefore, using this diaphragm pump, the building drainage tank 21 has a maximum water depth of 1 m. The sewage can be efficiently stirred and aerated. However, a blower or a compressor can be used for the air pump. The blower has a feature that the flow rate of supplied air can be increased. Moreover, since a compressor can make discharge pressure high, it can be used conveniently for the stirring tank with a deep maximum water depth.

  The air pump 4 can increase the discharge pressure as the water depth of the agitation tank 1 becomes deeper and inject air into the rising pipe 3 in the form of bubbles. Therefore, the discharge pressure of the air pump 4 is set to an optimum value depending on the water depth of the stirring tank 1. The air lift pump 2 can increase the flow rate of the rising liquid by increasing the discharge flow rate of the air pump 4 and increasing the inner diameter of the ascending pipe 3. Accordingly, the inner diameter of the ascending pipe 3, the discharge flow rate and the discharge pressure of the air pump 4 are set so as to be optimal for the application.

Furthermore, the stirring device can supply the mixture to the riser 3 with an injector and mix the mixture with the liquid. The mixture is one of liquid, powder, gas, or a mixture of these. In the stirring apparatus shown in FIG. 9 , an injector 12 is connected to the riser 3 to supply a liquid mixture to the bottom of the riser 3. The injector 12 is a supply pump 13 that sucks a liquid mixture and sucks it into the ascending pipe 3. The mixture to be supplied from the supply pump 13 to the ascending pipe 3 is forcibly stirred and mixed with the liquid in the process of ascending the ascending pipe 3. This injector 12 is provided with a nozzle 14 upward at the bottom of the riser 3, and this nozzle 14 is connected to a supply pump 13. The injector 12 ejects the mixture from the nozzle 14 upward and mixes it with the liquid through the ascending pipe 3.

As shown in FIG. 10 , the injector 12 can also supply a liquid mixture in the middle of the air pipe 5. The injector 12 connects the supply hose 15 connected to the supply pump 13 to the air pipe 5 and supplies the mixture to the air pipe 5. In this stirring device, since the mixture is added to the air supplied to the riser 3, the air and the mixture are supplied together to the riser 3, and the mixture is mixed with the liquid in the riser 3. . The injector 12 described above supplies the liquid mixture to the riser 3. However, the gas mixture can also be supplied to the riser with the same structure, and can be mixed and dissolved in the liquid.

The stirring device of FIG. 11 is for mixing a powdery mixture into a liquid, and includes an injector 12 that supplies the powdery mixture to the riser 3. The injector 12 is connected to a supply pipe 17 connected to the powder tank 16 in the middle of the air pipe 5. The injector 12 sucks the powder mixture by an air ejector action in which the pressure is reduced by flowing through the air pipe 5 at a high speed, and the sucked powder mixture is supplied to the ascending pipe 3 using air as a carrier gas. Supply. The injector 12 can mix the mixture into a liquid without using a pump or the like that forcibly supplies the mixture to the riser 3. However, the powder mixture can be forcibly supplied to the riser and mixed with the liquid. The powdery mixture to be mixed with the liquid is dissolved in the liquid or uniformly dispersed without being dissolved.

DESCRIPTION OF SYMBOLS 1 ... Stirring tank 2 ... Air lift pump 3 ... Rising pipe 4 ... Air pump 5 ... Air piping 6 ... Discharge port 7 ... Suction port 8 ... Branch pipe 9 ... Air vent part 10 ... Bottom plate 11 ... Connecting arm 12 ... Injector 13 ... Supply pump 14 ... Nozzle 15 ... Supply hose 16 ... Powder tank 17 ... Supply pipe 20 ... Bill pit 21 ... Bill drain 22 ... Manhole 23 ... Drain pump 24 ... Public basin 30 ... Sewer

Claims (8)

A stirring device comprising a stirring tank (1) for storing a predetermined amount of liquid, and an air lift pump (2) for sucking the liquid in the stirring tank (1) from the bottom and discharging it to the top for stirring.
The air lift pump (2) is disposed in the agitation tank (1) so as to extend from the bottom to the liquid level, and the suction port (7) is curved at the bottom so as to face from the top to the bottom in the horizontal direction. A riser pipe (3) opening the discharge port (6), and an air pump (4) for supplying air to the bottom of the riser pipe (3),
The ascending pipe (3) is provided with a plurality of outlets (6) branched between the upper end and the bottom,
The discharge port (6) has a plurality of branch pipes (8) curved in the horizontal direction from the vertical direction so that the discharge port (6) faces in the horizontal direction,
The ascending pipe (3) is a pipe, connecting a drain pipe joint in the middle of the ascending pipe (3), and connecting the branch pipe (8) curved with a predetermined curvature radius,
With this branch pipe (8), the discharge port (6) arranged vertically is opened so as to face the same direction,
A stirring device having an air lift pump (2) configured to change the discharge port (6) to be discharged depending on the water depth of the stirring tank (1).   The stirring device according to claim 1, wherein the discharge port (6) is opened on both sides of the riser pipe (3).   An injector (12) for injecting liquid, powder, gas, or a mixture to be mixed is connected to the bottom of the ascending pipe 3, and supplied from the injector (12). The stirrer according to claim 1, wherein the mixture is mixed with the liquid rising into the riser (3). The stirring device according to claim 3 , wherein the injector (12) is connected in the middle of an air pipe (5) formed by connecting an air pump (4) and a riser pipe (3). The stirring device according to claim 3 , wherein the injector (12) comprises a supply pump (13) for supplying a liquid mixture.   The agitation device according to claim 1, wherein the agitation tank (1) is a building drainage tank (21), and the wastewater of the building drainage tank (21) is agitated by an air lift pump (2).   The stirring device according to claim 1, wherein the air pump (4) is a diaphragm pump.   The stirrer according to claim 1, wherein the rising pipe (3) has its upper end closed or opened.

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