JP2022038889A - Activated sludge treatment apparatus - Google Patents

Abstract

To provide an activated sludge treatment apparatus that improves the efficiency of using energy possessed by the flow of gas not dissolved in to-be-treated water.SOLUTION: An activated sludge treatment apparatus 1 comprises: a treatment tank 2 that can treat to-be-treated water by use of activated sludge; a supply section 4 that can supply oxygen-containing gas to the interior of the treatment tank 2; an air collection section 5 that can collect undissolved gas G that is not dissolved in the to-be-treated water in the supplied gas; an energy conversion section 6 that can convert kinetic energy obtained from the fluid flow accompanying the undissolved gas G into rotational energy; and a power generation section 7 capable of converting the rotational energy into electrical energy.SELECTED DRAWING: Figure 1

Description

The present invention relates to an activated sludge treatment apparatus.

Activated sludge treatment is known as one of the methods for treating wastewater and / or treated water such as sewage. In the activated sludge treatment, first, activated sludge containing aerobic microorganisms that are actively active in an environment with a high oxygen concentration is added to the water to be treated. Then, air is added to the water to be treated to which activated sludge has been added to make the oxygen concentration in the water to be treated a high oxygen concentration suitable for the activity of aerobic microorganisms. This makes it possible to actively activate the aerobic microorganisms contained in the activated sludge to treat the water to be treated.

A part of the air added to the water to be treated dissolves in the water to be treated, but the rest remains as undissolved air. Since the density of air is much smaller than the density of water to be treated, undissolved air flows upward when viewed from the direction of gravity. That is, a gas flow is generated in which the undissolved gas that is not dissolved in the water to be treated among the added gases rises in the water to be treated. In addition, a liquid flow in which the water to be treated flows is generated along with this gas flow. In activated sludge treatment, a blower or the like that sends air to the water to be treated consumes energy such as electric power, but if energy is extracted from these flows and used by generating electricity using these flows, activated sludge treatment is performed. Energy efficiency can be improved.

For example, in a treatment tank that treats water to be treated such as wastewater by adding active sludge and air, the treatment tank is provided with two water channels using a partition wall, and air is added to only one of the water channels to make the water to be treated. A system has been proposed in which a swirling water flow is generated, a water wheel is rotated by the swirling water flow, and power is generated by utilizing the rotation of the water wheel (Patent Document 1).

Japanese Unexamined Patent Publication No. 2005-299427

However, the system described in Patent Document 1 does not utilize the air flow in which the undissolved air rises, but merely rotates the turbine by utilizing the swirling water flow generated by the added air. Therefore, most of the energy of the gas flow in which the undissolved gas rises cannot be used for the rotation of the turbine, and there is room for improvement in power generation efficiency.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an activated sludge treatment apparatus for improving the energy utilization efficiency of a gas flow of an undissolved gas that is not dissolved in the water to be treated. Is.

As a result of diligent studies to solve the above problems, the present inventors have conducted an air collecting portion capable of collecting undissolved gas that is not dissolved in the water to be treated, and kinetic energy obtained from the gas flow of the undissolved gas. It has been found that the above-mentioned problems can be achieved by providing an energy conversion unit capable of converting the gas into rotational energy, and the present invention has been completed. Specifically, the present invention provides the following.

The invention according to the first feature is a treatment tank capable of treating water to be treated using active sludge, a supply unit capable of supplying a gas containing oxygen to the inside of the treatment tank, and the supplied gas. Among them, an air collecting unit capable of collecting undissolved gas not dissolved in the water to be treated, an energy conversion unit capable of converting kinetic energy obtained from a fluid flow accompanying the undissolved gas into rotational energy, and the rotational energy. Provided is an active sludge treatment apparatus comprising a power generation unit capable of converting the gas into electric energy.

According to the invention according to the first feature, the oxygen-containing gas supplied from the supply unit is supplied to the water to be treated, and the oxygen concentration contained in the water to be treated is used for the activity of aerobic microorganisms contained in the activated sludge. Set to a suitable oxygen concentration. As a result, aerobic microorganisms are active and the water to be treated can be treated efficiently. In addition, among the fluid flows associated with the gas flow due to the undissolved gas that is not dissolved in the water to be treated, the liquid flow generated by the gas flow agitates and mixes the water to be treated and the activated sludge, and is contained in the activated sludge. Aerobic microorganisms can treat the entire treated water. Further, the liquid flow creates a wave on the surface of the water to be treated, and when this wave breaks, oxygen in the atmosphere is taken into the water to be treated. Therefore, the oxygen concentration in the water to be treated becomes a more suitable oxygen concentration due to the activity of aerobic microorganisms contained in the activated sludge.

Then, the undissolved gas that is not dissolved in the water to be treated is collected by the air collecting unit to become a fluid flow accompanying the gas flow of the undissolved gas, and the kinetic energy obtained from this fluid flow is converted into rotational energy by the energy conversion unit. To. In order to convert not only the kinetic energy obtained from the liquid flow that is a part of the fluid flow but also the kinetic energy obtained from the gas flow of the undissolved gas into rotational energy, the swirling water flow generated by the added air is used. The kinetic energy obtained from the gas flow of undissolved gas, which is not used in the method of rotating the water wheel, can also be used. That is, according to the invention according to the first feature, it is possible to improve the energy utilization efficiency of the gas flow of the undissolved gas.

According to the invention according to the first feature, since the undissolved gas is collected by the air collecting portion, the flow rate of the fluid flow per fixed time increases. This increases the kinetic energy of the fluid flow. Therefore, the kinetic energy converted into rotational energy by the energy conversion unit increases, and the power generation unit can convert more rotational energy into electrical energy. That is, the energy utilization efficiency of the fluid flow of the undissolved gas can be further improved.

Therefore, according to the invention according to the first feature, it is possible to provide an activated sludge treatment apparatus that improves the energy utilization efficiency of the fluid flow associated with the undissolved gas that is not dissolved in the water to be treated.

The invention according to the second feature is the invention according to the first feature, wherein the supply section can supply the gas from the lower side to the upper side in the direction of gravity, and the air collecting part is the supply part. The first opening, which is located substantially directly above the portion and takes in the undissolved gas from below, and the undissolved gas, which is located above the first opening and is taken in from the first opening, are above the first opening. It has a second opening to be delivered, the second opening is smaller than the first opening, and the energy conversion unit is located above the second opening and is delivered from the second opening. Provided is an apparatus in which the kinetic energy obtained from the fluid flow is arranged in an available position.

According to the invention according to the second feature, the air collecting unit is located substantially directly above the supply unit the undissolved gas that is not dissolved in the water to be treated among the gases supplied upward from the supply unit. It can be taken in without being missed by the opening and sent out from the second opening smaller than the first opening. Since the second opening is smaller than the first opening, the undissolved gas taken in by the first opening is collected and the kinetic energy obtained from the fluid flow increases. As a result, the energy conversion unit arranged at a position where the kinetic energy such as the gas flow sent from the second opening can be used can convert a larger kinetic energy into rotational energy. Therefore, the power generation unit can generate more electric energy.

Therefore, according to the invention according to the second feature, the energy utilization efficiency of the fluid flow associated with the undissolved gas can be further improved.

The invention according to the third feature is the invention according to the second feature, and when the air collecting portion is viewed from above, the center position of the second opening is the center position of the first opening. On the other hand, the present invention provides an apparatus having an eccentric position in a direction close to the outer periphery of the processing tank.

In the treatment of the water to be treated using activated sludge, the treatment efficiency of the water to be treated can be improved by keeping the oxygen concentration in the water to be treated in contact with the outer periphery of the treatment tank to which aerobic microorganisms are attached high. According to the invention according to the third feature, since there is a fluid flow accompanying the undissolved gas sent out from the second opening at a position eccentric toward the outer periphery of the treatment tank with respect to the center position of the first opening, the treatment tank. The oxygen concentration contained in the water to be treated in contact with the outer periphery can be kept higher, and the treatment efficiency of the water to be treated can be further improved.

According to the invention according to the third feature, even if the center position of the second opening is located near the outer periphery of the processing tank, the center position of the first opening is in the direction far from the outer periphery of the processing tank from the center position of the second opening. Due to the eccentric position, the first opening does not interfere with the outer circumference of the processing tank. As a result, the first opening can be made larger than the second opening. Therefore, the undissolved gas is collected by the air collecting portion having the first opening larger than the second opening, and the kinetic energy of the fluid flow increases as compared with the case where the size of the second opening is substantially the same as the size of the first opening. .. Then, the kinetic energy converted into the rotational energy by the energy conversion unit increases, and the power generation unit can generate more electric energy. Therefore, according to the invention according to the third feature, it is possible to simultaneously achieve the improvement of the energy utilization efficiency of the gas flow of the undissolved gas and the improvement of the treatment efficiency of the water to be treated.

The invention according to the fourth feature is the invention according to any one of the first to third features, wherein the energy conversion unit has a receiving part capable of receiving the fluid flow, and the receiving part has a receiving part. Provides a device that is rotatable and convex with respect to the direction of rotation.

According to the invention according to the fourth feature, since the shape of the receiving portion with respect to the rotation direction is a convex shape in which the frictional resistance between the water to be treated and the receiving portion is small, the frictional resistance generated when the receiving portion rotates in the rotational direction. Energy loss due to can be reduced. Further, the receiving portion that is convex with respect to the rotation direction has a concave shape on the opposite side of the rotation direction, that is, the side that receives the fluid flow accompanying the undissolved gas, and can receive the fluid flow without missing it. As a result, the energy conversion unit can convert the kinetic energy obtained from the fluid flow accompanying the undissolved gas received by the receiving unit into rotational energy. Therefore, according to the invention according to the fourth feature, it is possible to provide an activated sludge treatment apparatus capable of further improving the energy utilization efficiency of the fluid flow associated with the undissolved gas that is not dissolved in the water to be treated.

The invention according to the fifth feature is the invention according to the fourth feature, in which the rotation axis of the receiving portion is substantially horizontal, and the receiving portion is located at a position where the rotation direction is from the lower side to the upper side. Provided is an apparatus configured to be capable of receiving the fluid flow.

According to the invention according to the fifth feature, since the receiving portion receives the fluid flow at the position where the rotation direction is from the lower side to the upper side, the undissolved gas received by the receiving portion has a concave receiving portion with respect to the lower side. It is temporarily stored in. Since the density of the undissolved gas stored in the concave receiving portion is significantly smaller than the density of the water to be treated, the stored undissolved gas has buoyancy from the bottom to the top, that is, in the rotation direction of the receiving portion. Causes. Therefore, the energy conversion unit can convert not only the kinetic energy obtained from the fluid flow of the undissolved gas but also the buoyancy of the undissolved gas stored in the concave receiving portion into rotational energy. Therefore, it is possible to provide an activated sludge treatment apparatus capable of further improving the energy utilization efficiency of the gas flow of the undissolved gas that is not dissolved in the water to be treated.

The invention according to the sixth feature is the invention according to the fourth or fifth feature, and provides an apparatus in which the upper end of the receiving portion is lower than the constant water level of the water to be treated in the treatment tank.

When the receiving portion rotates at the boundary surface between the outside air and the water to be treated, wave-making resistance that loses energy occurs due to the receiving portion forming a wave at the boundary surface, and a part of the rotational energy is lost. According to the invention according to the sixth feature, when the water to be treated is filled to a constant water level in the treatment tank, the entire receiving portion including the upper end of the receiving portion is in the water to be treated, so that the receiving portion is outside air. Does not rotate at the interface between the water to be treated and the water to be treated. Therefore, the energy conversion unit can efficiently convert the kinetic energy obtained from the fluid flow accompanying the undissolved gas into the rotational energy without losing the rotational energy due to the wave-forming resistance. Therefore, it is possible to provide an activated sludge treatment apparatus capable of further improving the energy utilization efficiency of the fluid flow associated with the undissolved gas that is not dissolved in the water to be treated.

According to the present invention, it is possible to provide an activated sludge treatment apparatus capable of improving the energy utilization efficiency of the fluid flow associated with the undissolved gas that is not dissolved in the water to be treated.

FIG. 1 is a schematic schematic diagram showing a state of the activated sludge treatment apparatus 1 of the present embodiment when viewed from the direction of the rotating shaft 62.

Hereinafter, an example of a suitable embodiment for carrying out the present invention will be described with reference to FIG. It should be noted that this is only an example, and the technical scope of the present invention is not limited to this.

<Activated sludge treatment device 1>
The active sludge treatment device 1 includes a treatment tank 2 capable of storing water to be treated, an air supply unit 3 that sends gas outside the treatment tank 2 to the bottom of the treatment tank 2, and a gas sent from the air supply unit 3. The supply unit 4 capable of supplying the inside of the treatment tank 2, and the air collecting unit 5 capable of collecting the undissolved gas G that is not dissolved in the water to be treated among the gases supplied by the supply unit 4, and the undissolved gas. It includes an energy conversion unit 6 capable of converting kinetic energy obtained from a fluid flow accompanying G into rotational energy, and a power generation unit 7 capable of converting rotational energy into electrical energy.

[Treatment tank 2]
The treatment tank 2 is configured to be able to treat the water to be treated such as wastewater and sewage supplied from the outside by using activated sludge. As the treatment tank 2, it is known that the upper part of the water surface is closed and the upper part of the water surface is open.

FIG. 1 illustrates a treatment tank 2 having a lid on an opening provided above the water surface, but the present invention is not limited to this. The treatment tank 2 is not particularly limited as long as it is a tank or a container having an opening above the water surface. By having the opening, the undissolved gas G can be released to the outside of the treatment tank 2 through the opening. Therefore, it is possible to prevent the undissolved gas G from filling the inside of the treatment tank 2. The treatment tank 2 may be a tank or container having no lid or structure above the water surface, a tank or container having a lid above the water surface, or a tank or container having a structure such as a beam or a floor above the water surface. But it may be. Since the tank or container has no lid or structure above the water surface, the undissolved gas G can be released to the outside of the treatment tank 2 more efficiently. Since the treatment tank 2 is a tank or a container with a lid above the water surface, even if the water to be treated and / or the activated sludge emits a bad odor, the leakage of the bad odor to the outside is reduced. Further, since the treatment tank 2 is a tank or a container having a lid above the water surface, it is possible to reduce the temperature drop of the water to be treated in a cold region. The lid is not particularly limited as long as it is configured so that the undissolved gas G can escape to the outside when the treatment tank 2 is covered, but it is preferable that the lid has a structure that can be easily opened. .. The lid having a structure that can be easily opened facilitates maintenance of the treatment tank 2. Having a beam above the water surface increases the structural strength of the treatment tank 2. By having the floor above the water surface, the space above the floor can be used for various purposes.

Activated sludge contains a group of aerobic microorganisms that are active in an environment with high oxygen concentration. The aerobic microorganism group actively acts in an environment with a high oxygen concentration, decomposes pollutants such as organic substances in the water to be treated, and propagates and proliferates. Therefore, by storing the liquid containing the water to be treated and the activated sludge in the treatment tank 2 and creating an environment with a high oxygen concentration, it is possible to perform the treatment of decomposing pollutants such as organic substances in the water to be treated. The water to be treated, in which pollutants have been decomposed by aerobic microorganisms, is sent to the outside of the treatment tank 2.

It is preferable to configure the treatment tank 2 so that the water to be treated is supplied from the outside when the water level of the water to be treated in the treatment tank 2 becomes lower than the constant water level W of the treatment tank 2 shown in FIG. Further, it is preferable to configure the treatment tank 2 so that the water to be treated is sent to the outside of the treatment tank 2 when the water level of the water to be treated in the treatment tank 2 exceeds the constant water level W of the treatment tank 2. By configuring the treatment tank 2 as described above, even if the water level of the water to be treated is separated from the constant water level W, the water to be treated can be supplied and / or sent out so that the water level approaches the constant water level W.

[Air supply unit 3]
The air supply unit 3 has a function of sending the gas outside the processing tank 2 to the bottom of the processing tank 2.

In the example shown in FIG. 1, the air supply unit 3 includes a blower 31 that applies pressure to the gas and sends it out, and an air supply pipe 32 that transfers the gas sent out from the blower 31 to the bottom of the processing tank 2. There is. The gas transferred to the bottom of the treatment tank 2 is supplied to the supply unit 4, which will be described later.

[Blower 31]
The blower 31 applies pressure to the gas and sends it out toward the air supply tube 32. The type of the blower 31 is not particularly limited, and various conventional gas delivery means such as an air blower and an air pump can be used. The gas is not particularly limited as long as it contains oxygen, and examples thereof include air.

[Air supply tube 32]
The air supply pipe 32 transfers the oxygen-containing gas delivered from the blower 31 to the bottom of the treatment tank 2. The type of the air supply tube 32 is not particularly limited, and a tube capable of transferring various gases of the prior art can be used.

[Supply unit 4]
The supply unit 4 has a function of supplying the oxygen-containing gas delivered from the air supply unit 3 to the water to be treated stored in the treatment tank 2. In the example shown in FIG. 1, the supply unit 4 arranged inside the treatment tank 2 supplies the oxygen-containing gas delivered from the air supply unit 3 to the water to be treated stored in the treatment tank 2. The supply unit 4 is not particularly limited as long as the gas can be supplied to the water to be treated, and a means for supplying the gas of the prior art into the liquid can be used. The supply unit 4 includes, for example, an air diffuser (also referred to as a diffuser) for delivering gas through openings such as holes and gaps for delivering gas.

By having the supply unit 4 that supplies the gas to the water to be treated, the gas containing oxygen supplied from the supply unit 4 is supplied to the water to be treated, and the oxygen concentration contained in the water to be treated is contained in the activated sludge. The oxygen concentration can be adjusted to be suitable for the activity of aerobic microorganisms. As a result, aerobic microorganisms are active and the water to be treated can be treated efficiently.

As shown in FIG. 1, the position where the supply unit 4 is arranged is below the treatment tank 2 which is the inside of the water to be treated when the water to be treated is filled up to the constant water level W of the treatment tank 2. Is preferable. Since the density of the oxygen-containing gas supplied by the supply unit 4 is significantly smaller than the density of the water to be treated, the gas goes from the bottom to the top. Since the position where the supply unit 4 is arranged is below the treatment tank 2 which is the inside of the water to be treated, the oxygen-containing gas supplied by the supply unit 4 is directed from the lower side to the upper side of the treatment tank 2. It flows. As a result, the oxygen concentration contained in the entire water to be treated including not only the water to be treated below the treatment tank 2 but also the water to be treated above can be increased.

The number of supply units 4 is not particularly limited, but it is more preferable to include a plurality of supply units 4. By providing the plurality of supply units 4, it is possible to reduce the oxygen concentration contained in the water to be treated near the supply unit 4 from becoming high and the oxygen concentration contained in the water to be treated far from the supply unit 4 to be low. Thereby, for a larger amount of water to be treated, the oxygen concentration contained in the water to be treated can be set to an oxygen concentration suitable for the activity of aerobic microorganisms contained in the activated sludge.

[Undissolved gas G]
Of the oxygen-containing gas supplied from the supply unit 4, the undissolved gas G that is not dissolved in the water to be treated rises as bubbles as shown in FIG. A part of the oxygen-containing gas supplied to the water to be treated by the supply unit 4 is dissolved in the water to be treated, and the rest is an undissolved gas G that is not dissolved in the water to be treated. Since the density of the undissolved gas G is significantly smaller than the density of the water to be treated, the undissolved gas G produces a gas flow from the lower side to the upper side. In addition, among the fluid flows associated with the gas flow due to the undissolved gas G that is not dissolved in the water to be treated, the water to be treated and the activated sludge are agitated and mixed by the liquid flow generated by the gas flow, and are contained in the activated sludge. Aerobic microorganisms can treat the entire treated water.

Since the treatment tank 2 is a tank or container having an opening above the water surface, the liquid flow creates a wave on the surface of the water to be treated, and when this wave collapses, oxygen in the atmosphere is taken into the water to be treated. obtain. Therefore, the oxygen concentration contained in the water to be treated can be a more suitable oxygen concentration due to the activity of aerobic microorganisms contained in the activated sludge.

[Air collecting part 5]
The air collecting unit 5 is arranged substantially above the supply unit 4, and is configured to be able to collect the undissolved gas G that is not dissolved in the water to be treated among the gases supplied by the supply unit 4. The air collecting unit 5 is located substantially directly above the supply unit 4 and is located above the first opening 5A and the first opening 5A where the undissolved gas G can be taken in from below, and is taken in from the first opening 5A. It has a second opening 5B that sends out the undissolved gas G upward.

By providing the air collecting unit 5, the undissolved gas G is collected by the air collecting unit 5, so that the flow rate of the fluid flow per fixed time increases. This increases the kinetic energy of the fluid flow. Therefore, the kinetic energy of the fluid flow converted into rotational energy by the energy conversion unit 6 described later increases, and the power generation unit 7 can convert more rotational energy into electrical energy. That is, the energy utilization efficiency of the fluid flow of the undissolved gas G can be further improved.

The number of air collecting portions 5 is not particularly limited, but it is more preferable to include a plurality of air collecting portions 5. By providing the plurality of air collecting portions 5, a space is provided between the plurality of air collecting portions 5. The fluid flow can pass through the provided space. Therefore, the air collecting portion 5 does not stop the fluid flow flowing from the lower side to the upper side, and the water to be treated and the activated sludge can be agitated and mixed even above the air collecting portion 5. Therefore, the aerobic microorganisms contained in the activated sludge can also treat the water to be treated above the air collecting portion 5.

The shape of the air collecting portion 5 is not particularly limited as long as the undissolved gas G taken in from the first opening 5A can be collected, but the shape of the air collecting portion 5 is substantially a frustum that spreads from substantially above to substantially downward in the direction of gravity. It is preferably in the shape. As a result, the gas flow of the undissolved gas G from the lower side to the upper side is taken in by the open bottom surface (first opening 5A), is located substantially above the first opening 5A, and is smaller in size than the first opening 5A. It can be sent from the second opening 5B. The frustum is a three-dimensional figure obtained by removing a cone that shares a vertex and is reduced in a similar manner from the cone.

When the air collecting portion 5 has a substantially frustum shape, the shape may be a substantially frustum shape, a substantially frustum shape such as a substantially frustum shape, or a substantially frustum shape such as a substantially frustum shape. It is more preferable to have. Since it has a substantially quadrangular pyramid shape such as a substantially quadrangular frustum shape, the air collecting portion 5 can be configured by using a procedure for combining flat plate-shaped materials, which is easier than a procedure for forming a curved surface by bending or the like.

[First opening 5A]
As shown in FIG. 1, the air collecting unit 5 has a first opening 5A that takes in the undissolved gas G. By having the first opening 5A, the air collecting unit 5 can take in the undissolved gas G.

The position of the first opening 5A is not particularly limited, but is preferably a position substantially directly above the supply unit 4 and a position where the undissolved gas G can be taken in from below. As a result, the air collecting unit 5 takes the undissolved gas G that is not dissolved in the water to be treated among the gases supplied upward from the supply unit 4 by the first opening 5A located substantially directly above the supply unit 4. Can be taken in without spilling.

[Second opening 5B]
As shown in FIG. 1, the air collecting unit 5 has a second opening 5B that upwardly sends out the undissolved gas G taken in from the first opening 5A. By having the second opening 5B, the undissolved gas G taken in by the first opening 5A can be sent upward from the second opening 5B.

The size of the second opening 5B is not particularly limited, but as shown in FIG. 1, it is preferably smaller than the first opening 5A. The upper limit of the area of the second opening 5B is preferably 1/4 or less, more preferably 1/9 or less, and most preferably 1/16 or less with respect to the area of the first opening 5A. .. Since the area of the second opening 5B is equal to or less than a predetermined ratio with respect to the area of the first opening 5A, the air collecting unit 5 collects the undissolved gas G taken in by the first opening 5A and causes the fluid flow. The kinetic energy obtained from can be increased.

The lower limit of the area of the second opening 5B is preferably 1/400 or more, more preferably 1/100 or more, and most preferably 1/25 or more with respect to the area of the first opening 5A. .. When the area of the second opening 5B is equal to or more than a predetermined ratio with respect to the area of the first opening 5A, the fluid flow of the undissolved gas G becomes larger when the fluid flow of the undissolved gas G passes through the second opening 5B. The kinetic energy lost due to the frictional resistance between the undissolved gas G and the air collecting portion 5 can be reduced.

As shown in FIG. 1, the center position of the second opening 5B is preferably a position eccentric with respect to the center position of the first opening 5A in a direction closer to the outer periphery of the processing tank 2. In the treatment of the water to be treated using activated sludge, the treatment efficiency of the water to be treated can be improved by keeping the oxygen concentration in the water to be treated in contact with the outer periphery of the treatment tank 2 to which the aerobic microorganisms are attached high. By setting the center position of the second opening 5B to an eccentric position, the fluid flow accompanying the undissolved gas G can be arranged at a position closer to the outer periphery of the treatment tank 2 with respect to the center position of the first opening 5A. The oxygen concentration contained in the water to be treated near the outer periphery of the treatment tank 2 can be kept higher than the oxygen concentration contained in the water to be treated near the center of the treatment tank 2, and the treatment efficiency of the water to be treated can be improved. It can be improved even more.

The lower limit of the eccentricity of the center position of the second opening 5B with respect to the center position of the first opening 5A is preferably 50% or more, more preferably 66% or more, and most preferably 75% or more. .. When the eccentricity of the center position of the second opening 5B is equal to or more than a predetermined ratio with respect to the center position of the first opening 5A, the undissolved gas G is generated by the air collecting portion 5 having the first opening 5A larger than the second opening 5B. Collected, the kinetic energy of the fluid flow increases as compared to the case where the size of the second opening 5B is substantially the same as the size of the first opening 5A. As a result, the kinetic energy converted into rotational energy by the energy conversion unit 6 described later increases, and the power generation unit 7 can generate more electric energy. Therefore, it is possible to both improve the energy utilization efficiency of the gas flow of the undissolved gas G and improve the treatment efficiency of the water to be treated.

Further, the upper limit of the eccentricity of the central position of the second opening 5B with respect to the first opening 5A is preferably 95% or less, more preferably 90% or less, and most preferably 80% or less. When the eccentricity is high, the second opening 5B and the outer periphery of the processing tank 2 may interfere with each other. When the eccentricity of the center position of the second opening 5B is equal to or less than a predetermined ratio with respect to the center position of the first opening 5A, interference between the second opening 5B and the outer periphery of the processing tank 2 can be prevented. As a result, the first opening 5A can be made larger than the second opening 5B.

In the present embodiment, the eccentricity of the center position of the second opening 5B with respect to the center position of the first opening 5A is the vertical axis passing through the center position of the first opening 5A and the vertical axis passing through the center position of the second opening 5B. Let X be the distance from the center position of the first opening 5A and Y be the distance between the center position of the first opening 5A and the outer circumference of the first opening 5A located in the direction closest to the center position of the first opening 5A among the outer circumferences of the processing tank 2. At that time, (X / Y) is expressed as a percentage.

[Energy conversion unit 6]
The energy conversion unit 6 has a function of converting kinetic energy obtained from the fluid flow associated with the undissolved gas G into rotational energy.

The energy conversion unit 6 is not particularly limited as long as it can convert the kinetic energy obtained from the fluid flow accompanying the undissolved gas G into rotational energy, but is provided substantially above the second opening 5B as shown in FIG. The receiving portion 61 that can receive the fluid flow, the rotating shaft 62 that rotatably supports the receiving portion 61, and the motion of the fluid flow accompanying the undissolved gas G that rotates with the rotation of the receiving portion 61. It is preferable to have a first transmission unit 63 capable of transmitting rotational energy converted from energy to a power generation unit 7, which will be described later.

By providing the energy conversion unit 6 capable of converting the kinetic energy obtained from the fluid flow associated with the undissolved gas G into rotational energy, the undissolved gas G discharged from the air collecting unit 5 is accompanied by the gas flow and gas flow. The kinetic energy obtained from the fluid flow including the resulting liquid flow is converted into rotational energy by the energy conversion unit 6. Since the energy conversion unit 6 converts not only the kinetic energy obtained from the liquid flow that is a part of the fluid flow but also the kinetic energy obtained from the gas flow of the undissolved gas G into rotational energy, the energy conversion unit 6 The kinetic energy obtained from the gas flow of the undissolved gas G, which is not used in the method of rotating the water wheel by utilizing the swirling water flow generated by the added air, can also be used.

The position where the energy conversion unit 6 is arranged is not particularly limited, but is a position above the second opening 5B, and is arranged at a position where the kinetic energy obtained from the fluid flow sent out from the second opening 5B can be used. Is preferable. Due to the position above the second opening 5B, the gas flow of the undissolved gas G from the lower side to the upper side and the liquid flow generated by the gas flow toward the energy conversion unit 6. Then, by arranging the kinetic energy obtained from the fluid flow sent out from the second opening 5B at an available position, the energy conversion unit 6 moves the fluid flow before being collected by the air collecting unit 5. Kinetic energy larger than energy can be converted into rotational energy. Therefore, the power generation unit 7 can generate more electric energy.

The number of energy conversion units 6 is not particularly limited, but it is more preferable to include the same number of energy conversion units 6 as the number of the second openings 5B. By providing the same number of energy conversion units 6 as the number of the second openings 5B, the energy conversion units 6 can be arranged in just proportion at a position where the fluid flow sent from the second opening 5B can be used. Therefore, the kinetic energy of the fluid flow can be efficiently converted into the rotational energy.

[Receiver 61]
As shown in FIG. 1, the energy conversion unit 6 may have a receiving unit 61 that is capable of receiving a fluid flow, is rotatable with respect to the rotation shaft 62, and is convex with respect to the rotation direction. preferable.

Since the shape of the receiving portion 61 with respect to the rotation direction is a convex shape in which the frictional resistance between the water to be treated and the receiving portion 61 is small, the energy loss due to the frictional resistance generated when the receiving portion 61 rotates in the rotational direction can be reduced. Further, the receiving portion 61 which is convex with respect to the rotation direction has a concave shape on the opposite side of the rotation direction, that is, the side which receives the fluid flow accompanying the undissolved gas G, and can receive the fluid flow without missing it. As a result, the energy conversion unit 6 can convert the kinetic energy obtained from the fluid flow accompanying the undissolved gas G received by the receiving unit 61 into rotational energy without missing. Therefore, it is possible to provide the activated sludge treatment apparatus 1 that can further improve the energy utilization efficiency of the fluid flow associated with the undissolved gas G that is not dissolved in the water to be treated.

The energy conversion unit 6 preferably includes three or more receiving units 61 that rotate in conjunction with each other. By including three or more receiving portions 61 in which the energy conversion unit 6 rotates in conjunction with each other, even if a certain receiving portion 61 rotates and moves from a position where it can receive a fluid flow, it rotates in conjunction with the other. Any of the receiving portions 61 of the above can be moved to a position where it can receive the fluid flow.

As shown in FIG. 1, the receiving portion 61 has a substantially horizontal rotation axis 62, and includes a gas flow of undissolved gas G and a liquid flow generated by the gas flow at a position where the rotation direction is from the lower side to the upper side. It is preferable that it is configured to be able to receive the fluid flow.

Since the receiving portion 61 receives the fluid flow at the position where the rotation direction is from the lower side to the upper side, the undissolved gas G received by the receiving portion 61 is temporarily stored in the receiving portion 61 which is concave with respect to the lower side. Be done. Since the density of the undissolved gas G stored in the concave receiving portion 61 is significantly smaller than the density of the water to be treated, the stored undissolved gas G is from the bottom to the top, that is, in the receiving portion 61. Creates buoyancy in the direction of rotation. Therefore, the energy conversion unit 6 can convert not only the kinetic energy obtained from the fluid flow of the undissolved gas G but also the buoyancy of the undissolved gas G stored in the concave receiving portion 61 into rotational energy. Therefore, it is possible to provide the activated sludge treatment apparatus 1 that can further improve the energy utilization efficiency of the gas flow of the undissolved gas G that is not dissolved in the water to be treated.

As shown in FIG. 1, the upper end of the receiving portion 61 is preferably lower than the constant water level W of the water to be treated in the treatment tank 2.

When the receiving portion 61 rotates at the boundary surface between the outside air and the water to be treated, wave-making resistance that loses energy occurs due to the receiving portion 61 forming a wave at the boundary surface, and a part of the rotational energy is lost. When the upper end of the receiving portion 61 is lower than the constant water level W of the water to be treated in the treatment tank 2 and the water to be treated is filled to the constant water level W in the treatment tank 2, the receiving portion 61 including the upper end of the receiving portion 61 is included. Since the whole is in the water to be treated, the receiving portion 61 does not rotate at the interface between the outside air and the water to be treated. Therefore, the energy conversion unit 6 can efficiently convert the kinetic energy obtained from the fluid flow accompanying the undissolved gas G into the rotational energy without losing the rotational energy due to the wave-forming resistance. Therefore, it is possible to provide the activated sludge treatment apparatus 1 that can further improve the energy utilization efficiency of the fluid flow associated with the undissolved gas G that is not dissolved in the water to be treated.

The shape of the receiving portion 61 is not particularly limited as long as it is convex with respect to the rotation direction, and may be various shapes such as a bowl shape and a curved plate shape that are convex with respect to the rotation direction. When the receiving portion 61 is configured to be able to receive the gas flow of the undissolved gas G and the fluid flow including the liquid flow generated by the gas flow at a position where the rotation direction is from the lower side to the upper side, the shape of the receiving portion 61 is relative to the rotation direction. It is preferably bowl-shaped, which is convex. Due to the bowl shape, more undissolved gas G than the receiving portion 61 having a shape such as a curved plate shape is temporarily stored in the receiving portion 61 having a concave shape downward. Therefore, more buoyancy can be converted into rotational energy.

[Rotating shaft 62]
When the energy conversion unit 6 has the receiving unit 61, it is preferable that the energy conversion unit 6 has a rotating shaft 62 that rotatably supports the receiving unit 61, as shown in FIG. By having the rotating shaft 62 that rotatably supports the receiving portion 61, the receiving portion 61 can convert the kinetic energy obtained from the fluid flow into the rotational energy that rotates the rotating shaft 62.

A fluid flow including a gas flow of undissolved gas G and a liquid flow generated by the gas flow at a position where the energy conversion unit 6 includes three or more receiving portions 61 that rotate in conjunction with each other and the rotation direction is from the bottom to the top. When the receiving portion 61 is configured to be receiveable, it is preferable that the rotating shaft 62 is configured to be substantially horizontal. Since the rotating shaft 62 is configured substantially horizontally, the receiving portion 61 can be configured so that the rotation direction of any of the receiving portions 61 that rotate in conjunction with the rotating shaft 62 is from the lower side to the upper side. Therefore, any of the receiving portions 61 receives the gas flow of the undissolved gas G and the fluid flow including the liquid flow generated by the gas flow at a position where the rotation direction is from the lower side to the upper side.

[Transmission unit 63]
When the energy conversion unit 6 has a rotation shaft 62, the energy conversion unit 6 rotates with the rotation of the receiving unit 61 as shown in FIG. 1, and is a transmission unit capable of transmitting rotational energy to a transmission member 71 described later. It is preferable to have 63. By having a transmission unit 63 that rotates with the rotation of the receiving unit 61 and can transmit rotational energy to the transmission member 71 described later, the generator 72 is connected to the generator 72 via the transmission member 71 of the power generation unit 7, which will be described in detail later. Can transmit rotational energy. The configuration of the transmission unit 63 is not particularly limited, and may be various configurations capable of transmitting rotational energy to the transmission member 71 such as a pulley and a gear.

[Power generation unit 7]
The power generation unit 7 has a function of converting the rotational energy converted by the energy conversion unit 6 into electrical energy. In the example shown in FIG. 1, the power generation unit 7 has a transmission member 71 in which rotational energy is transmitted from the transmission unit 63, and a generator 72 that converts the rotational energy transmitted to the transmission member 71 into electrical energy.

The number of power generation units 7 is not particularly limited, but is preferably the same as the number of energy conversion units 6. Since the number of power generation units 7 is the same as the number of energy conversion units 6, the power generation unit 7 and the energy conversion unit 6 can be associated with each other on a one-to-one basis. Rotational energy can be converted into electrical energy without considering the difference in numbers. In addition, the installation cost of the equipment can be suppressed.

As shown in the example shown in FIG. 1, the power generation unit 7 may be configured separately from the energy conversion unit 6, and the energy conversion unit 7 may be connected to the rotating shaft 62 of the energy conversion unit 6 by connecting the generator 72 to the energy conversion unit 6. It may be integrally configured with 6. By configuring the power generation unit 7 separately from the energy conversion unit 6 and installing the power generation unit 7 at a position away from the water to be treated, it is possible to reduce the wetness of the power generation unit 7 by the water to be treated. By integrally configuring the power generation unit 7 with the energy conversion unit 6, it is possible to reduce the transmission loss of the rotational energy generated when the rotational energy is transmitted from the energy conversion unit 6 to the power generation unit 7.

[Transmission member 71]
When the energy conversion unit 6 has a transmission unit 63, as shown in FIG. 1, the power generation unit 7 transmits rotational energy from the transmission unit 63, and the transmitted rotational energy is transmitted to a generator 72 described later. It is preferable to have 71. As a result, rotational energy can be transmitted from the energy conversion unit 6 to the generator 72 via the transmission unit 63 and the transmission member 71.

The configuration of the transmission member 71 is not particularly limited. When the transmission unit 63 is a pulley, the transmission member 71 is preferably a belt capable of transmitting rotational energy from the transmission unit 63 by friction with the transmission unit 63. When the transmission unit 63 is a gear, the transmission member 71 is a toothed belt capable of transmitting rotational energy from the transmission unit 63 by engaging the tooth mold, or a transmission unit by engaging the tooth mold. It is preferably one of a transmission member that combines a gear that transmits rotational energy from 63, a shaft that transmits rotational energy, and a gear that transmits rotational energy to the generator 72 by engaging a tooth mold.

[Generator 72]
The power generation unit 7 has a generator 72 capable of converting rotational energy into electrical energy. By having a generator 72 capable of converting rotational energy into electrical energy, it is possible to convert rotational energy into electrical energy. Then, the energy efficiency of the activated sludge treatment performed by the activated sludge treatment device 1 is improved. The configuration of the generator 72 is not particularly limited, and can be configured by using various generators capable of converting the rotational energy of the prior art into electrical energy.

<How to use the activated sludge treatment device 1>
Hereinafter, an example of how to use the activated sludge treatment apparatus 1 will be described.

The user of the activated sludge treatment device 1 operates the blower 31 by turning on the switch of the blower 31 or the like. The blower 31 sends out a gas containing oxygen, and the sent out gas is transferred to a supply unit 4 provided at the bottom of the processing tank 2 via an air supply pipe 32. The gas transferred to the supply unit 4 is supplied from the supply unit 4 to the water to be treated stored in the treatment tank 2, and a part of the undissolved gas G is dissolved in the water to be treated. It is a gas flow that flows from the bottom to the top.

The gas flow of the undissolved gas G becomes a fluid flow accompanied by a liquid flow of the water to be treated, and goes to the air collecting unit 5 installed substantially above the supply unit 4. The undissolved gas G is taken into the air collecting unit 5 by the first opening 5A, collected, and sent out from the second opening 5B to the energy conversion unit 6. The energy conversion unit 6 converts the kinetic energy obtained from the fluid flow of the undissolved gas G into rotational energy.

This rotational energy is converted into electrical energy by the power generation unit 7. Therefore, it is possible to provide the activated sludge treatment apparatus 1 that improves the energy utilization efficiency of the gas flow of the undissolved gas G that is not dissolved in the water to be treated.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. Further, the effects described in the above-described embodiment are merely a list of the most preferable effects arising from the present invention, and the effects according to the present invention are not limited to those described in the above-mentioned embodiments. do not have.

Further, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations.

1 Activated sludge treatment device 2 Treatment tank 3 Air supply unit 31 Blower 32 Air supply pipe 4 Supply unit 5 Air collection unit 5A 1st opening 5B 2nd opening 6 Energy conversion unit 61 Receiving unit 62 Rotating shaft 63 Transmission unit 7 Power generation unit 71 Transmission Member 72 Generator G Undissolved gas W Constant water level

Claims (6)

A treatment tank that can treat water to be treated using activated sludge,
A supply unit capable of supplying a gas containing oxygen to the inside of the treatment tank,
Of the supplied gas, an air collecting unit capable of collecting undissolved gas that is not dissolved in the water to be treated, and an air collecting unit.
An energy conversion unit capable of converting kinetic energy obtained from the fluid flow associated with the undissolved gas into rotational energy,
A power generation unit that can convert the rotational energy into electrical energy,
An activated sludge treatment device. The supply unit can supply the gas from the lower side to the upper side in the direction of gravity.
The air collecting part is
A first opening located substantially above the supply section and taking in the undissolved gas from below.
It is located above the first opening and has a second opening that sends the undissolved gas taken in from the first opening upward.
The second opening is smaller than the first opening,
According to claim 1, the energy conversion unit is arranged at a position above the second opening and at a position where the kinetic energy obtained from the fluid flow sent from the second opening can be used. The device described. According to claim 2, when the air collecting portion is viewed from above, the center position of the second opening is eccentric to the center position of the first opening in a direction closer to the outer periphery of the processing tank. The device described. The energy conversion unit has a receiving unit capable of receiving the fluid flow.
The device according to any one of claims 1 to 3, wherein the receiving portion is rotatable and convex with respect to the rotation direction. The axis of rotation of the receiving portion is substantially horizontal.
The device according to claim 4, wherein the receiving portion is configured to be capable of receiving the fluid flow at a position where the rotation direction is from the lower side to the upper side. The device according to claim 4 or 5, wherein the upper end of the receiving portion is lower than the constant water level of the water to be treated in the treatment tank.

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