JP7565411B2 - Air diffusion system, air diffusion system operation method, and fan renewal method - Google Patents

Description

The present invention relates to an aeration system including an aeration device for dispersing fine air bubbles in a liquid, and a method for operating the aeration system. More specifically, the present invention relates to an aeration system including an aeration device used in an aeration tank for treating wastewater or the like, and a method for operating the aeration system.
The present invention also relates to a method for updating a blower used in an aeration system.

One known water treatment method is to provide an aeration tank in a water treatment device, install an aeration device in the aeration tank, and disperse gases such as air into the water being treated as fine bubbles using the aeration device. The aeration device converts gas supplied by a blower into fine bubbles via an aeration section and supplies them into the aeration tank. When the gas is air or oxygen, it can increase the amount of dissolved oxygen in the water being treated.

In water treatment using an aeration device, the power consumption for driving the aeration device accounts for a large proportion of the power consumption in the entire treatment. In addition, the amount of gas supplied by the aeration device affects the treatment efficiency of the water treatment. In particular, in biological treatment using aerobic microorganisms, it is known that the amount of air (oxygen supply) supplied by the aeration device greatly affects the activity of the microorganisms.
Therefore, in water treatment using an aeration device, it is required to keep the amount of gas supplied to the aeration tank by the aeration device within an appropriate range from the viewpoints of energy saving and maintaining and improving treatment efficiency.

For example, Patent Document 1 describes a wastewater treatment system that includes an aeration tank (aeration tank) that performs aerobic biological treatment by supplying air as the treated water is introduced, and an air flow controller that controls a blower (air blowing equipment) that supplies air to the aeration tank based on four measurements from a nitrate meter, an ammonia meter, a dissolved oxygen meter, and a water temperature meter. Patent Document 1 also describes using a blower equipped with an inlet vane to control the air flow rate, and providing multiple blowers to control the number of units.

JP 2014-133202 A

As described in Patent Document 1, in water treatment using an aeration device, it is known to use a blower equipped with an inlet vane, or to provide multiple blowers and control the number of blowers to control the blower's airflow, thereby controlling the amount of gas supplied from the aeration device.

On the other hand, since the aeration device in water treatment is placed underwater, in order to supply gas from the aeration device to the aeration tank, it is necessary to blow air at a pressure higher than the water pressure. In other words, in the aeration device in water treatment, it is necessary to maintain the pressure from the blower (hereinafter referred to as "air blowing pressure") and further adjust the air volume.
However, although Patent Document 1 describes setting the airflow rate taking into consideration the range of decrease in airflow pressure, it does not describe controlling the airflow rate while maintaining the airflow pressure. As described in Patent Document 1, when controlling the airflow rate taking into consideration the range of decrease in airflow pressure, there is a problem in that the range of the airflow rate that can be substantially controlled becomes narrow.

In addition, when installing an aeration device for multiple water treatment systems, if the range of air volume that can be controlled by the blower is narrow, it becomes difficult to supply the appropriate amount of gas from the blower to each aeration section, which creates the problem that it is not possible to achieve energy savings and maintain or improve treatment efficiency.

Furthermore, in recent years, the efficiency of the air diffusion section of the air diffusion device has been improved. However, when the range of air volume that can be controlled on the blower side is narrow, even if a highly efficient air diffusion section is used, the appropriate amount of gas cannot be supplied from the blower, and there is a problem that energy savings cannot necessarily be achieved.

Therefore, in water treatment using an aeration device, from the viewpoint of energy conservation and maintaining and improving treatment efficiency, it is required that the necessary amount of gas is appropriately supplied from the blower to keep the amount of gas supplied to the aeration tank within an appropriate range. Also, from the viewpoint of energy conservation and maintaining and improving treatment efficiency in water treatment using an aeration device, when updating the aeration device, it is necessary to also update the blower side so that it can send the necessary amount of gas to the aeration section.

The objective of the present invention is to provide an aeration system, an operating method for the aeration system, and a method for updating the blower that can save energy and maintain and improve treatment efficiency by enabling the blower to supply the required amount of gas to the aeration section within an appropriate range in a water treatment process in which aeration is performed for each of multiple water treatment systems.

As a result of extensive research into the above-mentioned problems, the inventors have discovered that in an aeration system in which an aeration section is provided for each water treatment system, by providing a main blower that blows air to multiple water treatment systems collectively, and a sub-blower that blows air to each water treatment system, it is possible to control the air blowing volume in accordance with the amount of gas required by the aeration section in each water treatment system, and have completed the present invention.
That is, the present invention relates to the following air diffusion system, an operating method of the air diffusion system, and a method of updating a blower.

The aeration system of the present invention, which aims to solve the above problems, is characterized by comprising an aeration section provided for each of a plurality of water treatment systems, a main blower that supplies gas to the aeration section, a main flow path connected to the main blower, a sub-flow path that branches off from the main flow path and is connected to the aeration section, and a sub-blower that supplies gas to the sub-flow path at a variable air volume.

According to the aeration system of the present invention, by connecting a sub-blower to each aeration section in parallel with a main blower that supplies gas to the entire aeration section, gas is supplied to the aeration section from the main blower and sub-blower. In other words, while the main blower maintains the necessary air pressure for air blowing, the sub-blower can control the air volume, widening the range of air volume controllable by the blower and enabling fine adjustment of the air volume. This allows the blower to supply the necessary amount of gas to the aeration section within an appropriate range, making it possible to save energy and maintain and improve the processing efficiency of the aeration system.

In addition, one embodiment of the air diffusion system of the present invention is characterized in that the maximum air volume of the sub-blower is lower than the maximum air volume of the main blower.
According to this feature, the sub-fan can be made smaller in size relative to the main fan, which makes it possible to further reduce the energy consumption of the air diffusion system.

In addition, one embodiment of the aeration system of the present invention is characterized in that the air volume required in the aeration section is greater than the air volume supplied from the main blower and less than the air volume supplied from the main blower and the sub-blower.
According to this feature, the air volume required by the air diffusion unit is not satisfied by the main blower alone, but is set within a range of air volume controllable by the sub-blower, thereby further improving the accuracy of fine adjustment of the air volume. Also, since the air volume required by the air diffusion unit is satisfied by the main blower and the sub-blower, the main blower and the sub-blower can each be made smaller. This makes it possible to further reduce energy consumption of the air diffusion system and maintain and improve the processing efficiency.

The method of operating an aeration system of the present invention for solving the above problems is a method of operating an aeration system having an aeration section provided for each of a plurality of water treatment systems, and is characterized in that it includes a main air blowing process for supplying gas to the entire aeration section, and a sub-air blowing process for supplying gas to each aeration section at a variable air volume.
According to the operating method of the air diffusion system of the present invention, by adding a sub-air blowing process with variable air volume for each air diffusion section to the main air blowing process that supplies gas to the entire air diffusion section, the air volume can be controlled by the sub-air blowing process while maintaining the air pressure required for air blowing by the main air blowing process, widening the range of air volume that can be controlled during air blowing and enabling fine adjustment of the air volume. This makes it possible to supply the necessary amount of gas to the air diffusion section within an appropriate range, making it possible to save energy and maintain and improve the processing efficiency of the air diffusion system.

The blower renewal method of the present invention for solving the above problems is characterized by comprising a merging step of merging the flow path of the sub-blower into a sub-flow path that branches off from the main flow path and is between an aeration section provided for each of a plurality of water treatment systems and the existing main blower, and a replacement step of replacing the existing main blower with a main blower having a maximum air volume smaller than that of the existing main blower.
According to the method for updating a blower of the present invention, by using a sub-blower, it is possible to effectively replace the existing main blower with a main blower having a smaller maximum air volume than the existing main blower without stopping the entire aeration system and without reducing the processing capacity of the aeration system. In addition, it is easy to adjust the maximum air volume of the blowers (main blower and sub-blower) of the entire aeration system after updating to match the amount of gas required by the aeration section. This makes it possible to further maintain and improve the energy saving and processing efficiency of the aeration system.

According to the present invention, in a water treatment process in which aeration is performed for each of a number of water treatment systems, it is possible to provide an aeration system, an operating method for the aeration system, and a method for updating the blower that can save energy and maintain and improve treatment efficiency by enabling the blower to supply the required amount of gas to the aeration section within an appropriate range.

FIG. 1 is a schematic diagram showing an aeration system according to an embodiment of the present invention. FIG. 2 is a schematic explanatory diagram showing the structure of an aeration section in an aeration system according to an embodiment of the present invention. FIG. 2 is a flow chart showing the operation control of the aeration system according to an embodiment of the present invention. FIG. 1 is a flow diagram showing one step of a method for updating a main blower according to an embodiment of the present invention. FIG. 1 is a flow diagram showing one step of a method for updating a main blower according to an embodiment of the present invention. FIG. 1 is a flow diagram showing one step of a method for updating a main blower according to an embodiment of the present invention. FIG. 1 is a flow diagram showing one step of a method for updating a main blower according to an embodiment of the present invention.

Below, the embodiments of the air diffusion system, the method of operating the air diffusion system, and the method of updating the blower according to the present invention will be described in detail with reference to the drawings. Note that the structure of the air diffusion system described in the embodiments is merely an example for explaining the air diffusion system according to the present invention, and is not limited thereto. Also, the method of operating the air diffusion system and the method of updating the blower described in the embodiments are merely an example for explaining the method of operating the air diffusion system and the method of updating the blower according to the present invention, and are not limited thereto.

The aeration system, the operating method of the aeration system, and the updating method of the blower of the present invention relate to water treatment involving aeration to disperse fine air bubbles in a liquid. Water treatment involving aeration is not particularly limited, but examples include drinking water treatment for improving the water quality of raw water such as river water, groundwater, and rainwater, as well as wastewater treatment such as industrial wastewater and domestic wastewater (sewage). In particular, the present invention can be suitably used for water treatment in which the treated water, such as wastewater, is biologically treated with activated sludge.

[Embodiments]
(Aeration system)
FIG. 1 is a schematic diagram showing the structure of an aeration system according to an embodiment of the present invention.
1, an aeration system 1 according to this embodiment includes a plurality of aeration tanks 2, an aeration section 3 provided for each aeration tank 2, a main blower 4, a main flow path 5 connected to the main blower 4, a sub-flow path 6 branching off from the main flow path 5 and connected to the aeration section 3, and a sub-blower 7 provided on the sub-flow path 6. The main blower 4 supplies gas to the aeration section 3 of each aeration tank 2 via the main flow path 5 and the sub-flow path 6. The sub-blower 7 supplies gas to the aeration section 3 of each aeration tank 2 via the sub-flow path 6.
In the aeration system 1 of this embodiment, one water treatment system S is formed for each sub-flow path 6, and Fig. 1 shows an aeration system 1 having two water treatment systems S1 and S2. The following description will be given of an aeration system 1 having two water treatment systems S1 and S2. Note that the number of water treatment systems S is not limited to this, and can be appropriately selected based on the treatment volume of the water W to be treated, etc.

The aeration tank 2 is for storing and diffusing the water to be treated W. Note that two aeration tanks (aeration tank 2A and aeration tank 2B) are shown in Fig. 1 .
The aeration tank 2 is not particularly limited as long as it is provided with an aeration unit 3 inside the aeration tank 2 and diffuses aeration into the water to be treated W. For example, the aeration tank 2 may be used as a biological treatment tank that contains various microorganisms or activated sludge used in biological treatment, or as a pH adjustment tank for the water to be treated W.
The aeration tank 2 may be composed of only one compartment, or the inside of the aeration tank 2 may be divided into a plurality of compartments.

The aeration section 3 is for supplying gas to the water to be treated W, and is provided in each aeration tank 2 (aeration tank 2A and aeration tank 2B). In Fig. 1, the aeration section 3A is shown provided for the aeration tank 2A, and the aeration section 3B is shown provided for the aeration tank 2B.
The aeration unit 3 is not particularly limited as long as it can generate fine bubbles and supply gas to the water to be treated W. For example, it may be equipped with an aeration body made of an aeration plate or an aeration tube.

The size, location, and installation method of the aeration unit 3 are not particularly limited. The size and location of the aeration unit 3 can be determined, for example, according to the size of the aeration tank 2 and the processing efficiency required for the aeration system 1. The installation method of the aeration unit 3 can be, for example, provided with a structure on the aeration unit 3 itself that allows it to be installed on the bottom or side of the aeration tank 2, or provided with a structure for fixing the aeration unit 3 to the bottom or side of the aeration tank 2.

An example of the aeration section 3 of this embodiment will be described with reference to FIG.
FIG. 2 shows a schematic explanatory diagram of the air diffusion section in the air diffusion system of this embodiment.
As shown in FIG. 2 , the aeration section 3 includes a header pipe 32 to which gas is supplied via a riser pipe 31 branching off from the secondary flow path 6, and an aeration unit 34 that is arranged along the axial direction of the header pipe 32 and has a plurality of aeration diffusers 33 to which gas is supplied from the header pipe 32.

The gas diffuser 33 has a structure for converting the gas supplied from the header pipe 32 into fine bubbles and diffusing them into the water W to be treated.
As shown in Fig. 2, the diffuser 33 may be, but is not limited to, an ultra-fine bubble diffuser tube, which is made of a tubular member wrapped with a membrane having fine pores through which gas passes and can generate fine bubbles. Other examples of the diffuser 33 include a diffuser cylinder made of porous synthetic resin or ceramic, and a diffuser tube made of a tubular member such as a flexible tube with many slits. The diffuser 33 is not limited to a tubular member, and may be, for example, a diffuser plate made of a square, round, or other plate-like member.

The number of aeration units 34 in the aeration section 3 is not particularly limited, and can be selected appropriately depending on the size of the aeration tank 2 and the processing efficiency required for the aeration system 1. For example, the aeration section 3 may be made up of one aeration unit 34, or may include multiple aeration units 34. Note that while FIG. 1 shows an aeration section 3 having two aeration units 34 in the aeration tank 2, this is not limiting.

The main blower 4 is for supplying gas to the multiple aeration tanks 2, and as shown in FIG. 1, supplies gas to each of the aeration tanks 2A and 2B via the main flow path 5.

The gas supplied from the main blower 4 can be selected depending on the type of aeration to be applied to the water W to be treated, and examples of such gas include air, oxygen, and nitrogen.

There are no particular limitations on the main blower 4 as long as it can compress and send gas. In the present invention, the term "blower" includes a blower and a compressor.
The main blower 4 in this embodiment is preferably capable of increasing pressure to the same extent as the water pressure in the aeration tank 2 or more. For example, a blower with a discharge pressure of 10 kPa or more (pressure ratio of 1.1 or more) can be used.

The main blower 4 may consist of a single blower, or may consist of multiple blowers arranged in parallel.

In order to reduce the number of control objects within the aeration system 1 and to facilitate air volume control, it is preferable to keep the air volume supplied from the main blower 4 constant. Therefore, the main blower 4 is not particularly limited as long as it is capable of continuous operation at least with a constant air volume, and may be one whose air volume is fixed at a constant value or one whose air volume is variable.

The auxiliary blower 7 is for supplying gas to the aeration section 3, and as shown in FIG. 1, is provided for each aeration tank 2 (for each water treatment system S) via a sub-flow path 6 branching off from the main flow path 5. Note that in FIG. 1, the auxiliary blower 7A is shown provided for the aeration tank 2A via the sub-flow path 6A, and the auxiliary blower 7B is shown provided for the aeration tank 2B via the sub-flow path 6B.

The gas supplied from the sub-blower 7 is usually the same as the gas supplied from the main blower 4, but is not limited to this and may be different from the gas supplied from the main blower 4. For example, if the supply of gas with a higher oxygen content than air is required in the aeration tank 2, it is possible to supply gas with the required oxygen content in the aeration tank 2 by supplying air from the main blower 4 and oxygen from the sub-blower 7, while suppressing the amount of oxygen used and reducing costs.

The sub-blower 7 is not particularly limited as long as it can compress and send gas, similar to the main blower 4. The sub-blower 7 is one with a variable air volume, and can vary the volume of air supplied to the air diffusion section 3. This makes it possible to adjust the air volume with the sub-blower 7 based on the air volume supplied from the main blower 4, and to supply gas according to the air volume required by the air diffusion section 3.

The means for varying the air volume of the sub-blower 7 is not particularly limited. For example, a control unit 71 may be provided to control the opening adjustment of the discharge valve of the sub-blower 7 and the opening adjustment of the inlet vane. The control unit 71 may directly receive data related to the air volume supplied from the sub-blower 7, or may calculate the air volume supplied from the sub-blower 7 by inputting parameters related to the air volume supplied from the sub-blower 7. The control unit 71 may also adjust the opening of the discharge valve and the opening of the inlet vane using an open/close switch or an inverter, etc., based on the input results or the calculation results.

The amount of air supplied to the air diffusion section 3 is the sum of the amount of air from the main blower 4 and the amount of air from the sub-blower 7. Therefore, as long as a certain amount of air is supplied by the main blower 4, the sub-blower 7 only needs to have the ability to fine-tune the amount of air supplied to the air diffusion section 3, and does not need to have the same capacity as the main blower 4. Therefore, it is preferable that the maximum air volume of the sub-blower 7 is lower than the maximum air volume of the main blower 4. This reduces the running costs of the sub-blower 7 and saves energy, which enables energy savings in the entire air diffusion system 1a.

It is preferable that a certain amount of air is supplied from the main blower 4. However, if the amount of air required by the air diffusion unit 3 can be supplied only by the main blower 4, the amount of air supplied from the main blower 4 must be adjusted, which complicates air volume control. Therefore, it is preferable that the amount of air required by the air diffusion unit 3 is greater than the amount of air supplied from the main blower 4 and less than the amount of air supplied from the main blower 4 and the sub-blower 7. This makes it possible to keep the amount of air supplied from the main blower 4 constant and adjust the amount of air by the sub-blower 7, which makes air volume control easier and further improves the accuracy of fine adjustment of the amount of air volume. In addition, since the amount of air required by the air diffusion unit 3 is satisfied by the main blower 4 and the sub-blower 7, the main blower 4 and the sub-blower 7 can each be made smaller, which enables energy saving for the entire air diffusion system 1a.

The air volume required by the aeration section 3 may be determined in advance in terms of the design of the aeration tank 2 and the aeration section 3, or may be set each time depending on the treatment efficiency within the aeration tank 2, etc.
The aeration system 1 of this embodiment may be provided with an air volume setting means (not shown) for setting the air volume required by the aeration section 3. Examples of the air volume setting means include providing various detectors in the aeration tank 2 for detecting parameters related to the treatment efficiency of the water W to be treated in the aeration tank 2, and providing a calculation section for calculating the air volume required by the aeration section 3 based on the detection results of the various detectors. Examples of the various detectors include a DO meter, an ammonia meter, a pH meter, and a water temperature meter.
Furthermore, the calculation results of the air volume setting means may be automatically or manually input to the control unit 71 provided in the sub-blower 7, and the sub-blower 7 may be automatically controlled or manually controlled by an operator.

(Operation method of the aeration system)
An example of operation control of the aeration system will be described with reference to FIG.
Fig. 3 is a flow diagram relating to the operation control of the aeration system in this embodiment. The device configuration and explanation of the aeration system in Fig. 3 are the same as those in Fig. 1. The thick arrows in Fig. 3 indicate the flow of gas.

First, the air volumes _QRA and _QRB required by the air diffusion units 3A and 3B provided in the air diffusion tanks 2A and 2B (hereinafter referred to as "required air volume _QRA " and "required air volume _QRB ") are determined. The required air volumes _QRA and _QRB may be values determined by design or may be values set by an air volume setting means.

Next, gas is supplied to each of the aeration tanks 2A and 2B from the main blower 4 through the main flow passage 5 (main blowing step). At this time, the air volume Q1 supplied from the main blower is smaller than the required air volumes _QRA and _QRB .
At the same time, gas is supplied from the sub-blower 7 through the sub-flow passage 6 to the air diffusion sections 3A and 3B provided in the air diffusion tanks 2A and 2B (sub-blower process-1). At this time, in the air diffusion tank 2A, the air volume Q2A obtained by subtracting Q1 from the required air volume _QRA of the air diffusion section 3A is set to the air volume supplied from the sub-blower 7A provided in the air diffusion tank 2A. In addition, in the air diffusion tank 2B, the air volume Q2B obtained by subtracting Q1 from the required air volume _QRB of the air diffusion section 3B is set to the air volume supplied from the sub-blower 7B provided in the air diffusion tank 2B. This makes it possible to supply an appropriate air volume for each required air volume _QRA , _QRB of the air diffusion sections 3A and 3B.
Furthermore, when the required air volumes _QRA and _QRB of the aeration sections 3A and 3B change with a change in the treatment conditions in the aeration tanks 2A and 2B, the required air volumes _QRA and QRB are satisfied by changing the air volumes Q2A and Q2B of the sub-blower 7A or 7B, respectively, while keeping the air volume _Q1 supplied from the main blower constant (sub-blower process-2). This makes it possible to always supply an appropriate air volume for the required air volumes _QRA and _QRB .

The aeration system and the operating method of the aeration system of this embodiment expand the range of air volume controllable by the blower in water treatment involving aeration, and enable the blower to appropriately supply the required amount of gas to the aeration section, thereby making it possible to reduce energy consumption of the entire aeration system and maintain and improve the treatment efficiency.

(How to update a blower)
The method for updating the blower in this embodiment effectively updates the blower 4 to supply an appropriate amount of air without stopping the entire air diffusion system, in accordance with the increased efficiency of the air diffusion unit 3. After updating the blower 4, an air diffusion system that exerts the same effect as the air diffusion system 1 in this embodiment is constructed.

The method for updating the fan in this embodiment will be described below with reference to FIGS.
Figures 4 to 7 are flow charts showing the steps involved in the main blower renewal method. The numbers in boxes in Figures 4 to 7 indicate the maximum airflow of the blower or the airflow required by the air diffuser, assumed for the purpose of explanation.
Note that the same structures and explanations as those of the aeration system shown in Fig. 1 will be omitted. Also, in Figs. 5 to 7, some of the configurations explained in Fig. 4 are omitted.

As shown in FIG. 4, the aeration system 10a before the update includes aeration tanks 2C-2E and existing main blowers 4A-4C, which are provided for each of a plurality of treatment systems S3-S5. The existing main blowers 4A-4C are arranged in parallel and supply gas to the aeration sections 3C-3E in the aeration tanks 2C-2E through the main flow path 5. The aeration sections 3C-3E are connected to sub-flow paths 6C-6E branched from the main flow path 5. Here, the maximum air volume of the existing main blowers 4A-4C is set to 150 (m ³ /min), and the required air volume of the aeration sections 3C-3E is set to 100 (m ³ /min). Note that in FIG. 5 to FIG. 7 described below, the treatment systems S3-S5 and the aeration tanks 2C-2E are omitted from the illustration.

First, in the first step, as shown in Fig. 4, the existing main blower 4C is removed, and the flow path of the sub-blower 7C is merged into the sub-flow path 6C connected to the air diffusion unit 3C (merging step-1). At this time, the maximum air volume of the sub-blower 7C is set to 50 ( ^m3 /min). Then, the air diffusion unit 3C is replaced with a high-efficiency air diffusion unit 3F with a required air volume of 70 ( ^m3 /min).
Here, in order to continue stable air diffusion, it is generally preferable that the total maximum air volume of the blowers exceeds the total required air volume of the air diffusion section. However, for example, if the existing main blower 4C is simply removed, the total maximum air volume of the existing main blowers 4A and 4B does not exceed the total required air volume of the air diffusion sections 3C to 3E, so the entire air diffusion system 10a must be stopped once. On the other hand, as shown in FIG. 4, by providing the auxiliary blower 7C, the total maximum air volume of the blowers exceeds the total required air volume of the air diffusion section, so that the removal of the existing main blower 4C and the renewal of the air diffusion section 3C can be performed smoothly. In addition, by providing the auxiliary blower 7C, which has a smaller maximum air volume than the removed main blower 4E, the entire air diffusion system 10a can save energy.

In the second stage, as shown in Fig. 5, the existing main blower 4B is removed and replaced with a main blower 4D having a smaller maximum air volume than the existing main blower 4B (replacement step-1). At this time, the maximum air volume of the main blower 4D is set to 75 ( ^m3 /min). The flow path of the sub-blower 7D is merged with the sub-flow path 6D connected to the air diffusion unit 3D (merging step-2). At this time, the maximum air volume of the sub-blower 7D is set to 50 ( ^m3 /min). Then, the air diffusion unit 3D is replaced with a highly efficient air diffusion unit 3G with a required air volume of 70 ( ^m3 /min).

Then, in the third step, as shown in Fig. 6, the existing main blower 4A is removed and replaced with a main blower 4E having a smaller maximum air volume than the existing main blower 4A (replacement step-2). At this time, the maximum air volume of the main blower 4E is set to 75 ( ^m3 /min). Also, the flow path of the sub-blower 7E is merged with the sub-flow path 6E connected to the air diffusion unit 3E (merging step-3). At this time, the maximum air volume of the sub-blower 7E is set to 50 ( ^m3 /min). Then, the air diffusion unit 3E is replaced with a highly efficient air diffusion unit 3H having a required air volume of 70 ( ^m3 /min).

Finally, as shown in Figure 7, by removing the main blower 4D, the aeration sections 3C-3E are updated to the highly efficient aeration sections 3F-3H, and the existing main blowers 4C-4E are updated to the main blower 4E and the sub-blowers 7C-7E. This significantly reduces the total required air volume on the aeration section side and the total maximum air volume on the blower side, making it possible to save energy on both the aeration section side and the blower side.

As described above, by gradually updating the main blowers 4C-4E and the aeration units 3C-3E, it is possible to update the blowers without shutting down the entire aeration system 10a and without reducing the processing efficiency of the aeration system 10a. Furthermore, the updated aeration system 10b can be a combination of blowers (main blower 4E and sub-blowers 7C-7E) that have a range of blowing volumes suitable for the required air volume of the highly efficient aeration units 3F-3H.

The above-mentioned stages of updating the blowers are merely examples of implementation, and are not intended to be limiting. For example, in each stage, it is sufficient that the confluence step and replacement step are performed so that the total maximum air volume of the blowers (main blower and sub blower) exceeds the total required air volume of the air diffusion section.

According to the blower renewal method of this embodiment, as the efficiency of the air diffuser increases, a method of updating a blower can be provided that can maintain and improve the energy saving and processing efficiency of the air diffusion system by updating to a blower that can perform air volume control suitable for a highly efficient air diffuser. In particular, by carrying out the blower renewal method of this embodiment in conjunction with an update to increase the efficiency of the air diffusion section, it becomes possible to fully utilize the performance of the highly efficient air diffusion section.

The above-mentioned embodiment shows an example of an aeration system, an operating method of an aeration system, and a method for updating a blower. The aeration system, operating method of an aeration system, and updating method of a blower according to the present invention are not limited to the above-mentioned embodiment, and the aeration system, operating method of an aeration system, and updating method of a blower according to the above-mentioned embodiment may be modified as long as the gist of the system is not changed.

For example, in the aeration system and the operating method of the aeration system of this embodiment, the amount and quality of the water W to be treated introduced into the aeration tank 2 may be measured, and the air volume required by the aeration section 3 may be determined based on the measurement results. This improves the accuracy of data related to the amount of gas required for the aeration section, making it possible to improve the treatment efficiency of the aeration system.
Furthermore, if the amount and quality of the water W to be treated introduced into the aeration tank 2 change depending on the time of day or the calendar, such as the human life cycle, the air volumes supplied from the main blower and the sub blower may be estimated based on data on the time of day and the calendar from past performance, etc. This makes it possible to improve the treatment efficiency of the aeration system without increasing the number of measurement points for parameters related to the amount and quality of the water W to be treated.

The aeration system, the control method for the aeration system, and the method for updating the blower of the present invention can be used in water treatment that involves aeration to disperse fine air bubbles in a liquid. In particular, the present invention can be suitably used in water treatment in which the treated water, such as wastewater, is biologically treated with activated sludge.

1 Aeration system, 10a Aeration system before renewal, 10b Aeration system after renewal, 2A to 2E Aeration tank, 3A, 3B Aeration section, 3C to 3E Aeration section before renewal, 3F to 3H Aeration section after renewal, 31 Riser pipe, 32 Header pipe, 33 Aeration pipe, 34 Aeration unit, 4 Main blower, 4A to 4C Main blower before renewal, 4D, 4E Main blower after renewal, 5 Main flow path, 6A to 6E Sub-flow path, 7A to 7E Sub-blower, 71 Control unit, Q1 Gas supply amount from main blower, Q2A, Q2B Gas supply amount from sub-blower, Q _RA , Q _RB Required air volume of aeration section, S1 to S5 Water treatment system, W Water to be treated

Claims (3)

A method for updating an aeration system having at least one existing main blower, comprising:
a confluence step of confluence a flow path of the sub-blower with a sub-flow path that is branched from a main flow path connected to the existing main blower and is connected to an aeration unit provided in a plurality of water treatment systems;
and a replacement step of replacing at least one of the existing main blowers with a new main blower ,
A method for updating an aeration system, comprising: performing a merging step and an exchange step so that the sum of the maximum air volumes of the main blower and the sub-blowers exceeds the sum of the required air volume of the aeration section at each stage of the update. The method for updating an air diffusion system according to claim 1, wherein the maximum air volume of the new main blower is smaller than the maximum air volume of the existing main blower. 3. The method for updating an air diffusion system according to claim 1, wherein a maximum air volume of the sub-blower is smaller than a maximum air volume of the existing main blower or the new main blower.