CN1640827A - Aeration air-flow control device for sewage treatment plant - Google Patents

Abstract

The invention provides an aeration air volume control device in a sewage treatment plant with multiple series of advanced treatment processes, which can reduce the working cost of aeration, and can also reduce the initial cost and maintenance management cost. The device includes a first target value setting means 41 for setting the target value of the ammoniacal nitrogen concentration of the treated water; based on the measured value of the dissolved oxygen concentration measured by the dissolved oxygen concentration meter of the series of aerobic tanks equipped with an ammonia meter , respectively set the second target value setting means 132, 232 of the dissolved oxygen concentration target value of other series of aerobic tanks that are not provided with ammonia meters; The measured value of the ammoniacal nitrogen concentration is close to the target value of the aeration air volume of the ammoniacal nitrogen concentration target value. For the aeration device of the aerobic tank without the ammonia meter, the measured value of the respective dissolved oxygen concentration is close to the dissolved oxygen concentration. The controllers 40, 130 and 230 for the target value of the aeration air volume of the concentration target value.

Description

Aeration air volume control device for sewage treatment plant

technical field

The present invention relates to an aeration air volume control device for a sewage treatment field including a multi-series sewage treatment process of the same treatment mode including aerobic tanks each equipped with an aeration device.

Background technique

In the past sewage treatment plants, the process called activated sludge method was mainly used to remove organic matter. However, due to the expansion of eutrophication in closed waters such as lakes and bays in recent years, people have increased the requirements for advanced sewage treatment. It is not only required to remove organic matter, but also required to remove substances affecting eutrophication, such as nitrogen and phosphorus.

FIG. 10 is a treatment system diagram of such a sewage treatment plant, and FIG. 11 is a schematic diagram showing the treatment system together with the arrangement of measuring devices of a conventional aeration air volume control device applied to the sewage treatment plant. The sewage treatment plant shown in Figure 10 includes three treatment systems of series 1, series 2 and series 3. The sewage sent in by the water delivery pipe 50 is sent to each series through No. 1 inflow pump 1, No. 2 inflow pump 101 and No. 3 inflow pump 201 respectively. Since series 1, series 2 and series 3 have the same structure, only the detailed structure of series 1 will be described.

The sewage sent by the No. 1 inflow pump 1 flows into the No. 1 initial sedimentation tank 2, where the suspended solids are settled. The outflow side of the No. 1 primary sedimentation tank 2 is connected to the inflow side of the No. 1 anaerobic tank 10 through a water delivery pipe 51 . The No. 1 anaerobic tank 11 and the No. 1 aerobic tank 12 are sequentially connected to the No. 1 anaerobic tank 10 . Then, the outflow side of the No. 1 aerobic tank 12 is connected to the inflow side of the No. 1 final sedimentation tank 13 through the water delivery pipe 52, and the outflow side of the No. 1 final sedimentation tank 13 is connected with a water delivery pipe 60 for discharging treated water. In addition, a water delivery pipe 53 is connected to the outlet of the circulating water pipe of the No. 1 aerobic tank 12 , and the No. 1 circulating pump 14 provides circulating water to the No. 1 anaerobic tank 11 through the water delivery pipe 53 . The No. 1 final sedimentation tank 13 is connected with a water delivery pipe 54 and a water delivery pipe 55, wherein, through the water delivery pipe 54, No. 1 return pump 15 returns a part of the treated water of the No. 1 final sedimentation tank 13 to the No. 1 anaerobic tank 10, Through the water delivery pipe 55, No. 1 remaining pump 17 will discharge the sludge. No. 1 initial sedimentation tank 2 is also connected with No. 1 primary sedimentation pump 18, and the No. 1 primary sedimentation pump 18 will pass the sludge deposited in No. 1 initial sedimentation tank 2 through water delivery pipe 58 and No. 1 remaining pump 17. The sludge is discharged together.

As shown in FIG. 11, the No. 1 aerobic tank 12 includes the No. 1 aeration device 9, and the No. 1 dissolved oxygen concentration meter 25 is provided for its control. Then, the No. 2 dissolved oxygen concentration meter 125 is installed on the No. 2 aerobic tank (not shown) of the series 2 whose detailed structure description is omitted, and the No. 3 dissolved oxygen concentration meter 225 is installed on the No. 3 aerobic tank of the series 3. slot (not shown). In FIG. 10, the process which has an anaerobic tank, an anoxic tank, and an aerobic tank is generally called A20 (Anaerobic-Anoxic-Oxic) process.

12 is a block diagram showing the structure of the conventional aeration rate control device for controlling the aeration device 9 of series 1-3, including setting the dissolved oxygen concentration (hereinafter also referred to as DO) of No. 1 aerobic tank 12 of series 1. ) No. 1 control target value setter 31 for the target value of the target value, No. 2 control target value setter 131 for setting the target value of the dissolved oxygen concentration of No. 2 aerobic tank of series 2, No. 3 for setting series 3 No. 3 control target value setter 231 of the target value of the dissolved oxygen concentration of the aerobic tank; and constitute a group of controllers by the following controllers: it includes No. 1 DO controller 30, and its function is to calculate No. 1 aeration The aeration air volume target value of device 9, so that the measured value of the dissolved oxygen concentration recorded by No. 1 dissolved oxygen concentration meter 25 follows the dissolved oxygen target value of No. 1 control target value setter 31; No. 2 DO controller 130 , its function is to calculate the aeration air volume target value of the No. 2 aeration device 109, so that the measured value of the dissolved oxygen concentration measured by the No. 2 dissolved oxygen concentration meter 125 follows the control target of the No. 2 control target value setter 131 value; No. 3 DO controller 230, its role is to calculate the aeration air volume target value of No. 3 aeration device 209, so that the measured value of the dissolved oxygen concentration measured by No. 3 dissolved oxygen concentration meter 225 follows No. 3 control target The control target value of the value setter 231.

Figure 11 and Figure 12 show the location of the dissolved oxygen concentration meter and the control of the aeration device when controlling the dissolved oxygen concentration in the sewage treatment plant shown in Figure 10, and the control of the dissolved oxygen can also be replaced by controlling the concentration of ammoniacal nitrogen concentration.

FIG. 13 shows the installed state of the ammonia meter at this time, and the same components as those in FIG. 11 are given the same symbols in the figure, so the description of these components will be omitted. Now, No. 1 ammonia meter 26 is set on No. 1 aerobic tank 12, and No. 2 ammonia meter 126 is set on No. 2 aerobic tank (not shown) of series 2 whose detailed structure description is omitted; No. 3 ammonia meter 226 is set on the No. 3 aerobic tank (not shown).

FIG. 14 is a block diagram showing the construction of an aeration amount control device controlling the aeration devices 9 of the series 1-3. Including the No. 1 control target value setter 41 for setting the target value of the ammoniacal nitrogen concentration of the No. 1 aerobic tank 12 of the series 1, and the device for setting the target value of the ammoniacal nitrogen concentration of the No. 2 aerobic tank of the series 2 No. 2 control target value setter 141, No. 3 control target value setter 241 for setting the target value of the ammoniacal nitrogen concentration of No. 3 aerobic tank of series 3; and a group of controllers constituted by the following controllers , it includes No. 1 ammonia controller 40 controlling the aeration rate of No. 1 aeration device 9, so that the measured value of the ammoniacal nitrogen concentration measured by No. 1 ammonia meter 26 follows No. 1 control target value setter 41. Ammonia nitrogen concentration target value; No. 2 ammonia controller 140 controlling the aeration rate of No. 2 aeration device 109, so that the measured value of the ammonia nitrogen concentration recorded by No. 2 ammonia meter 126 follows the value of No. 2 ammonia meter 126 Control target value; No. 3 ammonia controller 240 of the aeration rate of No. 3 aeration device 209, so that the measured value of the dissolved oxygen concentration recorded by No. 3 ammonia meter 226 follows the No. 3 control target value setter 241 control target value.

Here, since the sewage treatment of the series 1, the series 2, and the series 3 are the same, the treatment in the series 1 will be described. The sewage supplied by the No. 1 inflow pump 1 undergoes a part of sludge sedimentation in the No. 1 primary sedimentation tank 2, and the settled sludge passes through the No. 1 primary sedimentation pump 18 and is sent out to the final sludge through the water delivery pipe 58 drain system. The No. 1 anaerobic tank 10, the No. 1 anaerobic tank 11, and the No. 1 aerobic tank 12 are structures of a typical anaerobic-anaerobic-aerobic (A20) process for simultaneously removing organic matter, nitrogen, and phosphorus. The mechanism of nitrogen removal and phosphorus removal in this process will be described respectively below.

(a) Nitrogen removal

In the aerobic tank 12, using the oxygen supplied by the aeration device 9, the nitrifying bacteria oxidize the ammoniacal nitrogen (NH ₄ -N) into nitrite nitrogen (NO ₂ -N) and nitrate nitrogen (NO ₃ -N ). The nitrite nitrogen (NO ₂ -N) and nitrate nitrogen (NO ₃ -N) sent into the anaerobic tank 11 by the circulation pump 14 can convert the organic matter flowing into the sewage into a nutrient source under anaerobic conditions. The nitric acid respiration or nitrous acid respiration of the denitrification bacteria is reduced to nitrogen (N2) and removed to the outside of the system.

Representing the nitrogen removal reaction in terms of chemical formula, the nitrification reaction is:

(1)

NO ₂ ^- +1/2O ₂ →NO ₃ ^- (2)

When the denitrification reaction is recorded as the reaction when methanol is used as the organic matter, it is:

(3)

(b) Phosphorus removal

In the anaerobic tank 10 arranged before the aeration tank, the phosphorus storage bacteria in the activated sludge accumulate organic acids such as acetic acid in the body, and release phosphoric acid (PO ₄ ). Phosphorus in the phosphoric acid state released in excess, in the aerobic tank 12 arranged in the rear stage of the aeration tank, utilizes the excessive phosphorus uptake action of the phosphorus storage bacteria, and the phosphorus in the phosphoric acid state released above in the anaerobic tank 10 is absorbed. Activated sludge absorbs and removes phosphorus.

That is, organic acids such as acetic acid are required to advance this reaction. Because the concentration of organic acids becomes smaller when rainwater flows in, the organic matter available to phosphorus-storing bacteria decreases, and the spit-out reaction of phosphorus cannot be fully carried out, so the subsequent excess phosphorus uptake reaction is not sufficient, and biological phosphorus removal alone may not be able to obtain target water quality.

Therefore, in order to supplement it, there is also a flocculant storage tank for storing flocculants such as polyaluminum chloride, aluminum sulfate, and ferric sulfate. By injecting these flocculants, phosphorus components are precipitated in the form of aluminum phosphate and iron phosphate. And the method of removing phosphorus. The chemical formula at this time is as follows:

...(4)

In the sewage treatment plant, through the proper operation of various series of return pumps, circulation pumps, excess sludge extraction pumps, and aeration devices, the return flow, circulation flow, excess sludge extraction volume, and aeration air volume are managed to appropriate values. Work so that nitrogen, phosphorus and organic matter do not exceed the specified value of the discharge water quality.

Wherein the aeration device 9 provides the dissolved oxygen needed for microorganisms to remove nitrogen, phosphorus and organic matter, so it takes 40-60% of the working cost of the sewage treatment plant. If the supply amount of dissolved oxygen from the aeration device 9 is small, the water quality will deteriorate; on the other hand, if the supply amount increases, the operating cost will increase. That is, maintenance of water quality and reduction of operating costs are achieved by appropriately controlling the aeration device.

The conventional aeration air volume control device shown in Fig. 11 and Fig. 12 has the structure of respectively controlling the aeration devices 9, 109 and 209, and the dissolved oxygen concentration meters 25, 125 and 225 installed on the aerobic tanks of each series The measured value is controlled to the control target value set by the control target value setters 31, 131, and 231 (refer to, for example, Japanese Laid-Open Publication Hei 11-244894). On the other hand, another aeration air volume control device shown in Fig. 13 and Fig. 14 has the structure of respectively controlling the aeration devices 9, 109 and 209, and the No. 1 ammonia meter 26, The measured values of 126 and 226 are controlled to the control target values set by No. 1 control target value setters 41, 141, 142 (refer to, for example, Japanese Patent Laid-Open Publication No. 2003-200190).

Contents of the invention

The aeration air volume control device shown in Figure 11 and Figure 12 uses a dissolved oxygen concentration meter that is cheaper than the ammonia meter and is easier to maintain and manage. The initial cost is low and the maintenance and management are easy, but the control is based on indirect indicators such as dissolved oxygen. , so in order to maintain the discharge water quality at all times, it is necessary to work with a high dissolved oxygen target value, and the work cost required for aeration increases.

On the other hand, compared with the device shown in FIG. 11 and FIG. 12, the aeration air volume control device shown in FIG. 13 and FIG. 14 has high initial cost, and the maintenance and management of the sensor is too complicated. However, compared with the removal of organic matter and the absorption rate of phosphorus, the nitrification rate of nitrifying bacteria is slower. If the oxygen required for nitrification is provided, the air volume required for the removal of organic matter, phosphorus and nitrogen can be ensured. The aeration air volume is controlled by using the nitrogen concentration as an index, so it is possible to realize the operation that maintains the discharge water quality and reduces the work cost for aeration.

Since the present invention is completed in order to solve the above problems, the purpose of the present invention is to provide an aeration air volume control device for a sewage treatment plant, which can aerate The work cost is lower than the cost of the aeration air volume control device using the dissolved oxygen concentration meter to control the dissolved oxygen, and the initial cost and maintenance management cost are suppressed to be lower than the aeration using the ammonia meter of each series to control the concentration of ammoniacal nitrogen Air volume control device lower level.

The 1st invention of this application is:

An aeration air volume control device for a sewage treatment plant, which includes aerobic tanks with aeration devices that work according to their respective aeration air volume target values, multi-series sewage treatment processes with the same treatment method, and is characterized in that it includes The flow control of all inflowing sewage in all series is an equal flow control means; the ammonia meter for measuring the ammoniacal nitrogen concentration of the above-mentioned aerobic tanks in a certain series of multiple series; the ammonia meter for measuring the concentration of all series of aerobic tanks A dissolved oxygen concentration meter for a dissolved oxygen concentration; a first target value setting means for setting a target value of an ammoniacal nitrogen concentration in treated water; measured by a dissolved oxygen concentration meter for a series of aerobic tanks equipped with an ammonia meter Dissolved oxygen concentration measurement value, the second target value setting means for respectively setting the dissolved oxygen concentration target value of other series of aerobic tanks not equipped with ammonia meter; calculation of the aeration device of aerobic tank equipped with ammonia meter , make the measured value of the ammoniacal nitrogen concentration close to the target value of the aeration air volume of the ammoniacal nitrogen concentration target value, calculate the aeration device of the aerobic tank without the ammonia meter, make the respective measured values of the dissolved oxygen concentration close to The controller of the aeration air volume target value based on the dissolved oxygen concentration target value.

The 2nd invention of this application is:

An aeration air volume control device for a sewage treatment plant, which includes aerobic tanks with aeration devices that work according to their respective aeration air volume target values, multi-series sewage treatment processes with the same treatment method, and is characterized in that it includes The flow control of the inflowing sewage in all series is an equal flow control method; the ammonia meter measures the ammoniacal nitrogen concentration of the above-mentioned aerobic tank in a certain series among the multi-series; sets the ammoniacal nitrogen concentration target of the treated water The target value setting means of the value; the air diffusion efficiency input means of inputting the air diffusion efficiency of each of the above-mentioned aeration devices of each series; the aeration devices of other series of aerobic tanks are calculated according to the respectively input gas diffusion efficiency The air-dispersing efficiency ratio calculation means of the air-dispersing efficiency ratio of the air-dispersing efficiency of the aeration device of the series of aerobic tanks equipped with the ammonia meter; A controller whose measured value of the nitric nitrogen concentration is close to the target value of the aeration air volume of the ammoniacal nitrogen concentration target value; multiply the aeration efficiency ratio by the target value of the aeration air volume calculated by the controller, and it is better not to set the ammonia meter for calculation The aeration air volume computing means of the aeration air volume target value of the aeration device of the oxygen tank.

The invention of the 3rd of this application is:

An aeration air volume control device for a sewage treatment plant, which includes aerobic tanks with aeration devices that work according to their respective aeration air volume target values, multi-series sewage treatment processes with the same treatment method, and is characterized in that it includes measuring An inflow flowmeter for the flow rate of each of the above-mentioned multi-series inflowing sewage; an ammonia meter for measuring the ammoniacal nitrogen concentration of a certain series of aerobic tanks among the multi-series; a target value for setting the target value of the ammoniacal nitrogen concentration of the treated water Setting means; the input means for inputting the air diffusion efficiency of each of the above-mentioned aeration devices of each series; according to the respectively input air diffusion efficiency, obtain the respective gas diffusion efficiency of the aeration devices of other series of aerobic tanks Efficiency is provided with the aeration efficiency ratio of a series of aerobic tank aerobic tanks equipped with ammonia meter, the calculation method of the aeration efficiency ratio; calculating the ammoniacal nitrogen concentration of the aeration device of the aerobic tanks equipped with the above-mentioned ammonia meter The measured value is close to the controller of the aeration air volume target value of the ammoniacal nitrogen concentration target value; Calculate the aeration air volume from the flow of the sewage flowing into the series containing the above-mentioned aerobic tank with the ammonia meter and the aeration device The air magnification calculation method of the series air magnification; according to the air magnification multiplied by the aeration air volume target value calculated by the controller, the aeration air volume target value obtained by the multiplication, the air diffusion efficiency ratio multiplied by the input air diffusion efficiency The obtained value and the measured value of the flow rate of the influent sewage are an aeration air volume calculating means for calculating an aeration air volume target value of an aeration device in an aerobic tank not provided with an ammonia meter.

Through the above structure, the present invention can provide an aeration air volume control device for a sewage treatment plant. In a sewage treatment plant with multiple series of advanced treatment processes, it can reduce the working cost of aeration to less than that of using dissolved oxygen concentration The cost of the aeration air volume control device for controlling dissolved oxygen can be controlled, and the initial cost and maintenance management cost can be suppressed to a lower level than the aeration air volume control device for controlling the concentration of ammoniacal nitrogen using each series of ammonia meters.

Description of drawings

Fig. 1 is a system diagram showing a treatment system of a sewage treatment plant to which a first embodiment of the present invention is applied, together with the arrangement of measuring instruments.

Fig. 2 is a block diagram showing the construction of the first embodiment of the present invention.

Fig. 3 is a system diagram showing the arrangement of the treatment system and measuring instruments applied to the sewage treatment plant according to the second embodiment of the present invention.

Fig. 4 is a block diagram showing the construction of a second embodiment of the present invention.

Fig. 5 is a system diagram showing the arrangement of the treatment system and measuring instruments applied to the sewage treatment plant according to the third embodiment of the present invention.

Fig. 6 is a block diagram showing the construction of a third embodiment of the present invention.

Fig. 7 is a system diagram showing the arrangement of the treatment system and measuring instruments applied to the sewage treatment plant according to the fourth embodiment of the present invention.

Fig. 8 is a system diagram showing the arrangement of a treatment system and a measuring instrument applied to a sewage treatment plant according to a fifth embodiment of the present invention.

Fig. 9 is a block diagram showing the construction of a fifth embodiment of the present invention.

Fig. 10 is a system diagram of a sewage treatment plant that removes nitrogen and phosphorus in addition to organic matter.

Fig. 11 is a system diagram showing the arrangement of measuring instruments of the conventional aeration air volume control device applied to the sewage treatment plant shown in Fig. 10 together with the treatment system.

Fig. 12 is a block diagram showing the structure of a conventional aeration air volume control device using the measuring device of Fig. 10 .

Fig. 13 is a system diagram showing the arrangement of measuring instruments of another conventional aeration air volume control device applied to the sewage treatment plant shown in Fig. 10 together with the treatment system.

Fig. 14 is a block diagram showing the structure of another conventional aeration air volume control device using the measuring device of Fig. 13 .

Detailed ways

Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.

Example 1

Fig. 1 is a system diagram showing the treatment system of the sewage treatment plant applicable to the first embodiment of the present invention together with the arrangement of measuring instruments; since it is at the same position as Fig. 11 or Fig. 13 showing the conventional device The same marks are attached, so the description thereof is omitted. Among them, in order to control the aeration devices of each series of aerobic tanks, except that No. 1 dissolved oxygen concentration meter 25 and ammonia meter 26 are provided, it is the same as that in FIG. 11 or FIG. 13 is different in structure, and other structures are the same as those in Fig. 11 or Fig. 13 . The No. 1 dissolved oxygen concentration meter 25, the ammonia meter 26, the No. 2 dissolved oxygen concentration meter 125, and the No. 3 dissolved oxygen concentration meter 225 are all installed at the same position in the sewage flow direction.

Fig. 2 is a block diagram showing the construction of a first embodiment of the present invention applied to the above-mentioned sewage treatment plant. The device includes the No. 1 control target value setter 41 for setting the ammoniacal nitrogen concentration target value of the No. 1 aerobic tank 12 of the series 1; according to the measured value of the No. 1 dissolved oxygen concentration meter 25, the No. 2 of the calculation series 2 No. 2 control target value calculator 132 of the dissolved oxygen concentration target value of the aerobic tank; according to the measured value of the No. 1 dissolved oxygen concentration meter 25, the No. 2 control of the dissolved oxygen concentration target value of the No. 3 aerobic tank of the calculation series 3 The target value computing unit 232; also includes in order to make the measured value measured by the ammonia meter 26 follow the ammoniacal nitrogen concentration target value of the No. 1 control target value setter 41 and control the aeration rate of the No. 1 aeration device 9 No. 1 ammonia controller 40; in order to make the measured value of dissolved oxygen concentration measured by No. 2 dissolved oxygen concentration meter 125 follow the control target value of No. 2 control target value calculator 132 and control the aeration of No. 2 aeration tank 109 No. 2 DO controller 130 of quantity; In order to make the measured value of dissolved oxygen concentration measured by No. 3 dissolved oxygen concentration meter 225 follow the control target value of No. 3 control target value calculator 232 and control No. 3 aeration device 209 The No. 3 DO controller 230 constitutes one controller.

At this time, the No. 1 dissolved oxygen concentration meter 25 is connected to each input terminal of the No. 2 control target value calculator 132 and the No. 3 control target value calculator 232 through the signal line 25a. In addition, each output terminal of No. 1 control target value setter 41, No. 2 control target value calculator 132 and No. 3 control target value calculator 232 is connected to No. 1 ammonia controller 40, No. 2 DO controller 130 is connected to another input end of No. 3 DO controller 230; No. 1 ammonia meter 26, No. 2 dissolved oxygen concentration meter 125 and No. 3 dissolved oxygen concentration meter 225 are passed through signal lines 26a, 125a and 225a are connected with the other input ends of No. 1 ammonia controller 40 , No. 2 DO dissolved oxygen controller 130 and No. 3 DO controller 230 . In addition, each output terminal of No. 1 ammonia controller 40, No. 2 DO dissolved oxygen controller 130 and No. 3 DO controller 230 is connected to No. 1 aeration device 9 and No. 2 aeration device through signal lines 26b, 125b and 225b. 109 links to each other with No. 3 aerator 209.

The operation of the first embodiment configured as described above will be described below, particularly focusing on the structurally different parts from the conventional device. The sewage flowing into the sewage treatment plant comes out from the water delivery pipe 50 through No. 1 inflow pump 1, No. 2 inflow pump 101 and No. 3 inflow pump 201, and is provided to series 1, 2 and 3. In order to make the inflow amounts of each series equal, the first inflow pump 1, the second inflow pump 101, and the third inflow pump 201 are controlled by a control device not shown. The measured value of the No. 1 ammonia meter 26 installed on the No. 1 aerobic tank 12 is transmitted to the No. 1 ammonia controller 40 through the signal line 26a. No. 1 ammonia controller 40, in order to track the target value of ammoniacal nitrogen concentration set by No. 1 control target value setter 41, calculate No. 1 exposure through the PI controller shown in formula (5) and (6) for example The air volume target value of gas device 9:

$\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; Qair</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Qai</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 01</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Kp</span>}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}<span\; class="notranslate">\; \}</span>& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; SV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

Among them, Qair1(t): No. 1 aeration air volume target value at time t (m ³ /min)

Qair ₀₁ : Initial value of No. 1 aeration air volume (m ³ /min)

Kp: proportional gain (m ⁶ /g min)

T _I : Integral constant (min)

Δt: control period (min)

e(t): Deviation (mg/L)

SV _NH41 (t): No. 1 ammoniacal nitrogen concentration target value (mg/L)

PV _NH41 (t): Ammonia meter measurement value (mg/L).

No. 1 aeration device 9, in order to track the air volume target value calculated by (5) and (6), adjust the air volume through the opening adjustment of the air volume regulating valve and the reverse converter control of the aeration device (blower). At this time, the measured value of the dissolved oxygen concentration meter 25 in the No. 1 aerobic tank is transmitted to the No. 2 control target value calculator 132 and the No. 3 control target value calculator 232 through the signal line 25a.

No. 2 control target value computing unit and No. 3 control target value computing unit filter the measured value of dissolved oxygen meter 25 through formula (7) at a certain period (5 minutes to 30 minutes period), and pass the signal Line 132a, signal line 232a are sent to No. 2 DO controller 130 and No. 3 DO controller 230 respectively:

${\mathrm{<span\; class="notranslate">\; PVf</span>}}_{\mathrm{<span\; class="notranslate">\; 02</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; 02</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; 02</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; 02</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; 02</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; n\&Delta;t</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span>$

Among them, PVf ₀₂ (t): Filtration value of No. 1 dissolved oxygen concentration meter at time t

PV ₀₂ (t): Measured value of No. 1 dissolved oxygen concentration meter at time t

n: integer.

No. 2 DO controller 130 and No. 3 DO controller 230, in order to track the output value output by No. 2 control target value calculator and No. 3 control target value calculator, through the PI shown in formula (8) and (9) for example The controller calculates the air volume target values of No. 2 aeration device 109 and No. 3 aeration device 209 respectively:

$\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; Qairl</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Qai</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 01</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Kp</span>}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}<span\; class="notranslate">\; \}</span>& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; SV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

in:

Qairn(t): The target value of the aeration air volume of No. n at time t (m ³ /min)

Qair _0n : initial value of aeration air volume of number n (m ³ /min)

Kp: proportional gain (m ⁶ /g min)

T _I : Integral constant (min)

Δt: control period (min)

e(t): Deviation (mg/L)

SV _02n (t): No. n dissolved oxygen concentration target value (mg/L)

PV _02n (t): measured value of dissolved oxygen concentration meter n (mg/L) (n=2, 3).

No. 2 aeration device 109 and No. 3 aeration device 209, in order to track the air volume target values calculated by formula (8) and formula (9), through the adjustment of the opening of the air volume regulating valve and the reaction of the aeration device (blower) Adjust the air volume with the inverter control.

According to the first embodiment, compared with the devices shown in Fig. 13 and Fig. 14, since the number of ammonia meters with high initial cost and complicated maintenance and management is reduced, No. 2 of series 2 and series 3 is controlled by variable DO target value , No. 3 aerobic tank air volume, so compared with the device shown in Figure 11 and Figure 12, the effect of air volume reduction can be expected.

In addition, because the DO of each series is controlled to be equal, it is also suitable for the case where the air diffusion efficiency of the aerator is different. Especially when adding tanks, aeration devices with different aeration efficiency may be installed, and this control method is effective.

Example 2

Fig. 3 is a system diagram showing the arrangement of the treatment system and measuring instruments applied to the sewage treatment plant according to the second embodiment of the present invention. In the figure, the same components as those in FIG. 1 are assigned the same reference numerals, and therefore description thereof will be omitted. Here, the point of difference from the structure of Fig. 1 is that in order to control the aeration devices of the aerobic tanks of each series, only the ammonia meter 26 is installed on the No. There is no dissolved oxygen concentration meter installed on the aerobic tank.

Fig. 4 is a block diagram showing the structure of the aeration air volume control device of the second embodiment. Wherein, the No. 1 ammonia meter 26 is connected to one input end of the No. 1 ammonia controller 40 through the signal line 26a, and the No. 1 control target value setter 41 is connected to the other input end of the No. 1 ammonia controller 40 through the signal line 41a . The output end of the No. 1 ammonia controller 40 is connected to the No. 1 aeration device 9 through the signal line 26b. In addition, the diffuser efficiency input unit 43 of the No. 1 aerator, the diffuser efficiency input unit 143 of the No. 2 aerator and the diffuser of the No. The gas efficiency input part 243 is provided with the No. 1 to No. 2 gas diffusion efficiency ratio calculation part 144 of No. 2 aeration device 109 to No. 1 aeration device diffusion efficiency input part 43's gas diffusion efficiency ratio computing part 144 and the calculation No. 3 aerator. The air diffusion efficiency ratio calculation unit 244 of No. 1 to No. 3 air diffusion efficiency ratio of the air diffusion efficiency ratio of the aeration device 209 to the No. 1 aerator diffusion efficiency input unit 43 . In addition, No. 2 aeration is also provided by multiplying the output of No. 1 to No. 2 diffuser efficiency ratio calculation unit 144 by the aeration air volume output by No. 1 ammonia controller 40 to calculate the aeration air volume of No. 2 aeration device 109. Air volume computing unit 145; multiply the output of No. 1 to No. 3 diffusion efficiency ratio computing unit 244 by the aeration air volume output by No. 1 ammonia controller 40, and calculate the No. 3 aeration volume of the aeration air volume of No. 3 aeration device 209 The output terminals of the air volume computing unit 245 are respectively connected to the No. 2 aeration device 109 and the No. 3 aeration device 209 through signal lines.

The operation of the second embodiment constructed as above will be explained as follows. The sewage flowing into the sewage treatment plant comes out from the water delivery pipe 50, and is supplied to series 1-series 3 through No. 1 inflow pump 1, No. 2 inflow pump 101 and No. 3 inflow pump 201. In order to equalize the amount of inflow into each series, the inflow pumps No. 1 to No. 3 are controlled by the control means not shown in the figure. The measured value of the ammonia meter 26 installed on the No. 1 aerobic tank 12 is transmitted to the No. 1 ammonia controller 40 through the signal line 26a. No. 1 ammonia controller 40, in order to track the target value of ammoniacal nitrogen concentration set in No. 1 control target value setter 41, calculate No. 1 exposure through the PI controller shown in formula (10), (11) for example The air volume target value of gas device 9:

$\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; Qair</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Qai</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 01</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Kp</span>}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}<span\; class="notranslate">\; \}</span>& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; SV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

in:

Qair1(t): Target value of No. 1 aeration air volume at time t (m ³ /min)

Qair ₀₁ : Initial value of No. 1 aeration air volume (m ³ /min)

Kp: proportional gain (m ⁶ /g min)

T _I : Integral constant (min)

Δt: control period (min)

e(t): Deviation (mg/L)

SV _NH41 (t): No. 1 ammoniacal nitrogen concentration target value (mg/L)

PV _NH41 (t): Ammonia meter measurement value (mg/L).

No. 1 aeration device 9, in order to track the air volume target value calculated by (10) and (11), adjust the air volume through the opening adjustment of the air volume regulating valve and the reverse converter control of the aeration device (blower). Using No. 1 and No. 2 diffuser efficiency ratio computing units 144 and No. 1 and No. 3 diffuser efficiency ratio calculators, according to the input diffuser efficiencies, the ammonia meter is controlled through calculations shown in (12) and (13) formulas. Calculate the ratio of air diffusion efficiency between the series (series 1) and other series:

C ₁₂ =Kl ₂ /Kl ₁ ... (12)

C ₁₃ =Kl ₃ /Kl ₁ ... (13)

in:

C ₁₂ : Air diffusion efficiency ratio of No. 1 and No. 2

C ₁₃ : Air diffusion efficiency ratio of No. 1 and No. 3

Kl ₁ : Air diffusion efficiency of No. 1 aeration device

Kl ₂ : Diffusion efficiency of No. 2 aeration device

Kl3: Diffusion efficiency of No. 3 aeration device.

The air diffusion efficiency ratio calculated here, together with the No. 1 aeration air volume target value at time t calculated by the formulas (10) and (11), are sent to the No. 2 aeration air volume calculation unit and the No. 3 aeration volume respectively. The air volume calculation unit calculates the aeration air volume target value through the calculation of (14) and (15):

Qair2(t)＝C ₁₂ ·Qair1(t)...(14)

Qair3(t)＝C ₁₃ ·Qair1(t)...(15)

in:

Qaim(t): Target value of aeration air volume n at time t (m ³ /min)

C ₁₂ : Air diffusion efficiency ratio of No. 1 and No. 2

C ₁₃ : Air diffusion efficiency ratio of No. 1 and No. 3.

No. 2 aeration device 109 and No. 3 aeration device 209, in order to track the air volume target values calculated by formulas (14) and (15) respectively, through the adjustment of the opening of the air volume regulating valve and the reaction of the aeration device (blower) Adjust the air volume with the inverter control.

According to the second embodiment, although it is necessary to set the correct air diffusion efficiency in the input part in advance, compared with the conventional aeration air volume control device shown in Fig. 13 and Fig. 14, the problems of high initial cost and complicated maintenance and management are reduced. The number of ammonia meters controls the air volume of No. 2 aeration device 109 of series 2 and No. 3 aeration device 209 of series 3. In addition, unlike Example 1, the dissolved oxygen concentration meter is not used for control, and only the ammonia meter is used for control, so there is no control abnormality due to an abnormality of the dissolved oxygen concentration meter, and the stability can be improved.

Example 3

Fig. 5 is a system diagram showing the arrangement of the treatment system and measuring instruments applied to the sewage treatment plant according to the third embodiment of the present invention. In the figure, the same reference numerals are assigned to the same components as those in FIG. 3 , and thus their descriptions are omitted. Here, the difference from the structure in Fig. 3 is that No. 1 inflow flowmeter 5 is set on the sewage delivery side of No. 1 inflow pump 1 of series 1, and No. 2 inflow flow meter 5 is set on the sewage delivery side of No. 2 inflow pump 101 of series 2. Meter 105, No. 3 inflow flow meter 205 is set on the sewage outflow side of No. 3 inflow pump 201 of series 3.

Fig. 6 is a block diagram showing the structure of an aeration air volume control device according to a third embodiment. In the figure, the same symbols are attached to the same components as those in FIG. 4 showing the second embodiment, so the description thereof will be omitted. In the second embodiment shown in Figure 4, in addition to newly setting the No. 1 air magnification calculation part 246 of the magnification of the aeration air volume of the No. 1 aeration device 9, one input of the calculation part is the No. 1 ammonia controller. The aeration air volume target value of 40, another input is the measured value of No. 1 inflow flowmeter 5, No. 2 aeration air volume calculation part 145 according to No. 1 to No. 2 air diffusion efficiency ratio calculation part 144, No. 2 inflow Calculate the output of No. 105 and No. 1 air magnification calculation unit 246 to calculate the aeration air volume target value for No. 2 aeration device 109. No. 3 aeration air volume calculation unit 245 is based on No. 1 to No. 3 diffusion efficiency ratio calculation unit 244 , No. 3 inflow flow meter 205 and No. 1 air magnification computing unit 246's respective outputs, computing the structure of the aeration air volume target value of No. 3 aeration device 209 and the second embodiment shown in Fig. 4 Except for the difference in structure, it has the same structure as that of FIG. 4 .

The operation of the third embodiment constructed as described above will be explained as follows. The sewage flowing into the sewage treatment plant comes out from the water delivery pipe 50 through No. 1 inflow pump 1, No. 2 inflow pump 101 and No. 3 inflow pump 201, and is provided to series 1-series 3. The measured value of the No. 1 ammonia meter 26 installed on the No. 1 aerobic tank 12 is transmitted to the No. 1 ammonia controller 40 through the signal line 26a. No. 1 ammonia controller 40, in order to track the target value of ammoniacal nitrogen concentration set in the No. 1 control target value setter 41, calculate No. 1 exposure through the PI controller shown in formula (16), (17) for example The air volume target value of gas device 9:

$\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; Qair</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Qai</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 01</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Kp</span>}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}<span\; class="notranslate">\; \}</span>& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; SV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

Qair1(t): Target value of No. 1 aeration air volume at time t (m ³ /min)

Qair ₀₁ : Initial value of No. 1 aeration air volume (m ³ /min)

Kp: proportional gain (m ⁶ /g min)

T _I : Integral constant (min)

Δt: control period (min)

e(t): Deviation (mg/L)

SV _NH41 (t): No. 1 ammoniacal nitrogen concentration target value (mg/L)

PV _NH41 (t): Ammonia meter measurement value (mg/L).

No. 1 aeration device 9, in order to track the aeration air volume target value calculated by (16) and (17), adjust the air volume through the adjustment of the opening of the air volume regulating valve and the reverse converter control of the aeration device (blower) . Utilize No. 1 and No. 2 diffuser efficiency ratio computing units 144, No. 1 and No. 3 diffuser efficiency ratio calculators, according to the input diffuser efficiency, through the calculations shown in (18) and (19) to control the passing through the ammonia meter Calculate the ratio of air diffusion efficiency between the series (series 1) and other series:

C ₁₂ =Kl ₂ /Kl ₁ ... (18)

C ₁₃ =Kl ₃ /Kl ₁ ... (19)

in:

C ₁₂ : Air diffusion efficiency ratio of No. 1 and No. 2

C ₁₃ : Air diffusion efficiency ratio of No. 1 and No. 3

Kl ₁ : Air diffusion efficiency of No. 1 aeration device

Kl ₂ : Diffusion efficiency of No. 2 aeration device

Kl3: Diffusion efficiency of No. 3 aeration device.

On the other hand, in the No. 1 air magnification calculation unit, from the measured value of the No. 1 inflow flow meter 5 and the No. 1 aeration air volume target value calculated by the formulas (16) and (17), the formula (20) is used to calculate 1 No. air magnification.

Al(t)＝Qair1(t)/Qin1(t) ...(20)

in:

Al(t): Calculated value of No. 1 air magnification

Qair1(t): Target value of No. 1 aeration air volume at time t (m ³ /min)

Qin ₁ (t): No. 1 inflow flow (m ³ /min)

The No. 1 air magnification calculated here, and the No. 1 No. 2 air diffusion efficiency ratio calculated by (18) and (19), the No. 1 No. 3 air diffusion efficiency ratio, No. 2 inflow flowmeter 105, No. 3 The measured values of the inflow flow meter 205 are sent to the No. 2 aeration air volume calculation unit and the No. 3 aeration air volume calculation unit respectively, and the target value of the aeration air volume is calculated through the calculation of formulas (21) and (22):

Qair2(t)＝C ₁₂ ·Al(t)·Qin ₂ (t)...(21)

Qair3(t)＝C ₁₃ ·Al(t)·Qin ₃ (t)...(22)

in:

Qair2(t): Target value of No. 2 aeration air volume at time t (m ³ /min)

Qair3(t): target value of No. 3 aeration air volume at time t (m ³ /min)

C ₁₂ : Air diffusion efficiency ratio of No. 1 and No. 2

C ₁₃ : Air diffusion efficiency ratio of No. 1 and No. 3

Al(t): Calculated value of No. 1 air magnification

Qin ₂ (t): No. 2 inflow flow at time t (m ³ /min)

Qin ₃ (t): No. 3 inflow flow at time t (m ³ /min)

No. 2 aeration device 109 and No. 3 aeration device 209, in order to track the air volume target values calculated by formulas (21) and (22) respectively, through the adjustment of the opening of the air volume regulating valve and the adjustment of the aeration device (blower) Inverter control is used to adjust the air volume.

Through the third embodiment, compared with the conventional aeration air volume control device shown in Fig. 13 and Fig. 14, the number of ammonia meters with high initial cost and complicated maintenance and management is reduced, and the No. 2 aeration device 109 and the No. 2 aeration device of the control series 2 are reduced. The air volume of No. 3 aeration device 209 of series 3. In addition, unlike Example 1, the dissolved oxygen concentration meter is not used for control, and only the ammonia meter is used for control, so there is no control abnormality due to an abnormality of the dissolved oxygen concentration meter, and the stability can be improved. In addition, compared with the first embodiment and the second embodiment, a new effect is obtained, that is, even when the amount of sewage flowing into each series is different, it can be controlled.

Example 4

Fig. 7 is a system diagram showing the arrangement of the treatment system and measuring instruments applied to the sewage treatment plant according to the fourth embodiment of the present invention. In the figure, the same components as those in FIG. 1 are assigned the same reference numerals, and therefore description thereof will be omitted. Here, an inflow flowmeter 3 and an inflow total nitrogen meter 4 for measuring the inflowing nitrogen are arranged on the original water delivery pipe through which No. 1 inflow pump 1, No. 2 inflow pump 101, and No. 3 inflow pump 201 divert sewage. The illustrated multiplication tool multiplies the measured value of the inflow flow meter and the measured value of the inflow total nitrogen meter, and the resulting nitrogen load information is input to No. 1 ammonia controller 40 (referring to Fig. 1 ), through for example (23), (24 ), (25) formula calculation of the air volume target value of No. 1 aeration device. In this way, the use of nitrogen load information to calculate the air volume target value of the aeration device is not only limited to embodiment 1, but also applicable to embodiment 2 and embodiment 3:

$\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; Qair</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Aair</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; TN</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; Qin</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 3</span>}& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; twenty\; three</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; Aair</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Aai</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 01</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Kp</span>}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}<span\; class="notranslate">\; \}</span>& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; twenty\; four</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; SV</span>}}_{\mathrm{<span\; class="notranslate">\; NH</span>}\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 25</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

in:

Qair1(t): Target value of No. 1 aeration air volume at time t (m ³ /min)

Aair1(t): Calculated value of No. 1 nitrogen load factor (m ³ /g)

TN(t): measured value of total nitrogen meter (mg/L)

Qin(t): measured value of inflow flowmeter (m ³ /min)

Aair ₀₁ : Initial value of No. 1 nitrogen load air multiplier

Kp: proportional gain (m ⁶ /g min)

T _I : Integral constant (min)

Δt: control period (min)

e(t): Deviation (mg/L)

SV _NH4I (t): No. 1 ammoniacal nitrogen concentration target value (mg/L)

PV _NH41 (t): Ammonia meter measurement value (mg/L).

The measurement of the inflow total nitrogen can also be carried out by setting the inflow total nitrogen meter on the water delivery pipe of the front section or the back section of each initial sedimentation tank of series 1, 2, and 3 and adding up the respective measured values. In Examples 1-3, the inflow flow is controlled to equalize the flow into each pool, so even if the flow meter is not used to measure the overall flow as in this example, it is also possible to measure only the flow of each series. Influent total nitrogen.

Through the fourth embodiment, the aeration operation cost can be reduced and the initial cost and maintenance management cost can also be suppressed at a low level. In addition to this effect, since the nitrogen load information of the influent sewage is introduced, it is also possible to obtain tracking ammonia. A new effect that the followability of the target value of nitrogen concentration control is high.

Example 5

Fig. 8 is a system diagram showing the treatment system and the arrangement of measuring instruments applied to a sewage treatment plant according to a fifth embodiment of the present invention. In the figure, the same reference numerals are assigned to the same parts as those in FIG. 5 applied to the third embodiment, and therefore description thereof will be omitted. Here, in the No. 1 aerobic tank 12 of the series 1, in addition to the No. 1 ammonia meter 26, a dissolved oxygen concentration meter 25 is also installed, and the No. 2 aerobic tank of the series 2 (not shown in the figure) is installed. The dissolved oxygen concentration meter 125 is different in structure from that of FIG. 5 in that the No. 3 dissolved oxygen concentration meter 225 is installed on the No. 3 aerobic tank not shown in the series 3. In addition, it has the same structure as that of FIG. same construction.

Fig. 9 is a block diagram showing the structure of an aeration air volume control device according to a fifth embodiment. In the figure, the same reference numerals are attached to the same components as those in FIG. 6 showing the third embodiment, and therefore description thereof will be omitted. In this embodiment, No. 1 DO limit is set on the output sections of No. 1 ammonia controller 40, No. 2 aeration air volume computing unit 145, and No. 3 aeration air volume computing unit 245 of the third embodiment shown in FIG. (Limiter) device 47, No. 2 DO limiting device 147, and No. 3 DO limiting device 247 differ from FIG. 6 in structure, but have completely the same structure as FIG. 6 . No. 1 DO limiting device 47, No. 2 DO limiting device 147, and No. 3 DO limiting device 247 are respectively based on the measured values of No. 1 dissolved oxygen concentration meter 25, No. 2 dissolved oxygen concentration meter 125, and No. 3 dissolved oxygen concentration meter 225. The air volume target value of each series of aeration devices is controlled.

The operation of the fifth embodiment constructed as above will be explained as follows. The lower limit value and the upper limit value of the dissolved oxygen concentration are set for No. 1 DO restricting device 47 , No. 2 DO restricting device 147 , and No. 3 DO restricting device 247 . When the measured values of No. 1 dissolved oxygen concentration meter 25 , No. 2 dissolved oxygen concentration meter 125 , and No. 3 dissolved oxygen concentration meter 225 are respectively between the set upper and lower limit values, it operates as in the third embodiment. However, when the measured values of No. 1 dissolved oxygen concentration meter 25, No. 2 dissolved oxygen concentration meter 125 and No. 3 dissolved oxygen concentration meter 225 deviate from the set upper and lower limit values respectively, switch to the formula (26), (27), (28), (29) and (30) show the lower limit or upper limit value as the target value of the dissolved oxygen concentration certain control, DO does not deviate from its upper and lower limits, so that No. 1 DO limit Device 47, No. 2 DO limiting device 147 and No. 3 DO limiting device 247 work. The calculation formula of DO limiting device is shown in formula (26)-(30):

$\left\{\begin{array}{cc}{\mathrm{<span\; class="notranslate">\; Q</span>}}^{<span\; class="notranslate">\; \&prime;</span>}\mathrm{<span\; class="notranslate">\; air</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}^{<span\; class="notranslate">\; \&prime;</span>}\mathrm{<span\; class="notranslate">\; ai</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Kp</span>}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 26</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; do</span>}\mathrm{<span\; class="notranslate">\; min</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; 02</span>}\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 27</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

Q′airn(t)=Qairn(t) ...(28)

$\left\{\begin{array}{cc}{\mathrm{<span\; class="notranslate">\; Q</span>}}^{<span\; class="notranslate">\; \&prime;</span>}\mathrm{<span\; class="notranslate">\; air</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}^{<span\; class="notranslate">\; \&prime;</span>}\mathrm{<span\; class="notranslate">\; ai</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Kp</span>}<span\; class="notranslate">\; \{</span>\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}& <span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 29</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; do</span>}\mathrm{<span\; class="notranslate">\; max</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; PV</span>}}_{\mathrm{<span\; class="notranslate">\; 02</span>}\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 30</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

in:

Q′airn(t): The target input value of aeration air volume n at time t (m ³ /min)

Q′air _on : the initial value of the aeration air volume of No. n (m ³ /min)

Qairn(t): the input value of DO limiting device for number n aeration air volume target at time t (m ³ /min)

Kp: proportional gain (m ⁶ /g min)

T _I : Integral constant (min)

Δt: control period (min)

e(t): Deviation (mg/L)

DOmin: lower limit of dissolved oxygen concentration (mg/L)

DOmax: upper limit of dissolved oxygen concentration (mg/L)

PV _02n (t): measured value of dissolved oxygen concentration meter n (mg/L) (n=1-3)

According to the fifth embodiment, when the dissolved oxygen concentration exceeds the lower limit or upper limit, it is possible to switch to the control of constant dissolved oxygen concentration with the lower limit or upper limit as the target value, so as to maintain the treated water quality within a certain range. Inside.

The above-mentioned embodiments are applicable to the situation that the treatment system of the sewage treatment plant includes the A2O process, but the present invention is not limited to this application, as long as the standard activated sludge process, the circulating nitrification denitrification process, the AO process, and the carrier input process are carried out , Segmented inflow process and other sewage treatment processes for aeration, any treatment system is applicable.

The number of series is not limited to 3 series in this embodiment, and any series is applicable as long as it is 2 series or more.

In addition, the aeration device is not only each series of independent aeration devices as in the above embodiment, but also can provide air from one aeration device to multiple series of devices, and control the air regulating valve on the water delivery pipe to adjust the aeration. air volume.

Furthermore, the installation position of the ammonia meter can be on any part of the aerobic tank for aeration.

Claims (9)

1. The aeration air volume control device of the sewage treatment plant, which contains an aerobic tank with an aeration device working according to the respective aeration air volume target value, and has a multi-series sewage treatment process with the same treatment method, characterized in that, Including the flow control means to control the flow of all the inflowing sewage of the above-mentioned multi-series to the same amount; the ammonia meter for measuring the ammoniacal nitrogen concentration of the above-mentioned aerobic tank in a certain series of the above-mentioned multi-series; measuring all the above-mentioned multi-series A dissolved oxygen concentration meter for the dissolved oxygen concentration of the above-mentioned aerobic tank; a first target value setting means for setting a target value of the ammoniacal nitrogen concentration of the treated water of the above-mentioned sewage treatment plant; The measured value of the dissolved oxygen concentration measured by the dissolved oxygen concentration meter of the above-mentioned aerobic tank of the above-mentioned series is respectively set to the second target value setting of the dissolved oxygen concentration target value of the above-mentioned aerobic tank of the series without the above-mentioned ammonia meter. Fixed means; calculation is provided with the aeration device of the above-mentioned aerobic tank with the above-mentioned ammonia meter, so that the measured value of the ammoniacal nitrogen concentration is close to the first aeration air volume target value of the ammoniacal nitrogen concentration target value, and the calculation is not provided with the above-mentioned In the aeration device of the above-mentioned aerobic tank of the ammonia meter, the controller for making the measured values of the respective dissolved oxygen concentrations close to the target value of the 2nd-nth aeration air volume of the target value of the dissolved oxygen concentration is determined according to the above-mentioned controller. The calculated aeration air volume target value controls the above-mentioned aeration device. 2. the aeration air volume control device of sewage treatment plant according to claim 1, is characterized in that, comprises the inflow flowmeter of measuring above-mentioned sewage inflow; The inflow of the above-mentioned sewage and the total nitrogen concentration or both or any one of the information is used to calculate the above-mentioned first aeration air volume target value. 3. the aeration air volume control device of sewage treatment plant according to claim 1, is characterized in that, comprises the dissolved oxygen concentration meter that measures respectively the whole dissolved oxygen concentration of above-mentioned multi-series; Sets the upper and lower limits of above-mentioned dissolved oxygen concentration , the measured dissolved oxygen concentration of each of the above multi-series series does not deviate from the upper and lower limit values to control the limiting device of the aeration air volume. 4. The aeration air volume control device of the sewage treatment plant, which contains aerobic tanks with aeration devices that work according to their respective aeration air volume target values, and multi-series sewage treatment processes with the same treatment method, characterized in that, Including the flow control means to control the flow of all the inflowing sewage of the above-mentioned multi-series to be equal; the ammonia meter for measuring the ammoniacal nitrogen concentration of the above-mentioned aerobic tank in a certain series of the above-mentioned multi-series; setting the flow rate of the above-mentioned sewage treatment plant The target value setting means of the ammoniacal nitrogen concentration target value of the treated water; the air diffusion efficiency input means for inputting the gas diffusion efficiency of each of the above-mentioned aeration devices in each series of the above-mentioned multi-series; according to the respectively input gas diffusion efficiency, Calculate the air diffusion efficiency ratio of the air diffusion efficiency of the aeration devices of the above-mentioned aerobic tanks of other series to the gas diffusion efficiency ratio of the aeration devices of the above-mentioned aerobic tanks of the series in which the above-mentioned ammonia meter is installed in the above-mentioned multi-series Calculation means; computing the aeration device of the above-mentioned aerobic tank with the above-mentioned ammonia meter, the controller that makes the measured value of the ammoniacal nitrogen concentration close to the target value of the aeration air volume of the ammoniacal nitrogen concentration target value; the above-mentioned multi-series The calculation of the aeration air volume calculation of the aeration air volume target value of the aeration device of the above-mentioned aerobic tank without the above-mentioned ammonia meter is calculated by multiplying the air diffusion efficiency ratio between the series of the above-mentioned controller by the aeration air volume target value calculated by the above-mentioned controller means: control the above-mentioned aeration device according to the aeration air volume target value calculated by the above-mentioned aeration air volume calculation means. 5. the aeration air volume control device of sewage treatment plant according to claim 4, is characterized in that, comprises the inflow flowmeter of measuring above-mentioned sewage inflow; The inflow of the above-mentioned sewage and the total nitrogen concentration or both or any one of the information is used to calculate the above-mentioned first aeration air volume target value. 6. the aeration air volume control device of sewage treatment plant according to claim 4, is characterized in that, comprises the dissolved oxygen concentration meter that measures respectively the whole dissolved oxygen concentration of above-mentioned multi-series; Sets the upper and lower limits of above-mentioned dissolved oxygen concentration , the measured dissolved oxygen concentration of each of the above multi-series series does not deviate from the upper and lower limit values to control the limiting device of the aeration air volume. 7. The aeration air volume control device of the sewage treatment plant, which contains an aerobic tank with an aeration device that works according to the respective aeration air volume target values, and has a multi-series sewage treatment process with the same treatment method, characterized in that, It includes an inflow flow meter for measuring the flow rate of the respective inflowing sewage of the above-mentioned multiple series; an ammonia meter for measuring the ammoniacal nitrogen concentration of the above-mentioned aerobic tank in a certain series of the above-mentioned multiple series; setting the flow rate of the treated water of the above-mentioned sewage treatment plant The target value setting means of the ammoniacal nitrogen concentration target value; the air diffusion efficiency input means for inputting the air diffusion efficiency of each of the above-mentioned aeration devices in each series of the above-mentioned multiple series; Air diffusion efficiency ratio calculation means for the ratio of the air diffusion efficiency of the aeration devices of the above-mentioned aerobic tanks of the series to the aeration efficiency ratio of the aeration devices of the above-mentioned aerobic tanks of one series of the above-mentioned multiple series equipped with the above-mentioned ammonia meter Computation is provided with the aeration device of the above-mentioned aerobic tank of above-mentioned ammonia meter, makes the measured value of ammoniacal nitrogen concentration close to the controller of the aeration air volume target value of ammoniacal nitrogen concentration target value; The air magnification calculation means of calculating the air magnification of the series by calculating the flow rate of the series of sewage in the above-mentioned aerobic tank of the ammonia meter and the aeration air volume of the above-mentioned aeration device; The target value, the aeration air volume target value obtained by this multiplication, the value obtained by multiplying the air diffusion efficiency ratio by the input air diffusion efficiency, and the measured value of the flow rate of the influent sewage are calculated for the above-mentioned aerobic tank without the above-mentioned ammonia meter. The aeration air volume calculation means for the aeration air volume target value of the aeration device controls the aeration device based on the aeration air volume target value calculated by the aeration air volume calculation means. 8. The aeration air volume control device of sewage treatment plant according to claim 7, is characterized in that, comprises the inflow flowmeter of measuring above-mentioned sewage inflow; The total nitrogen meter of measuring the total nitrogen concentration of above-mentioned sewage, utilizes to measure The inflow of the above-mentioned sewage and the total nitrogen concentration or both or any one of the information is used to calculate the above-mentioned first aeration air volume target value. 9. The aeration air volume control device of sewage treatment plant according to claim 7, is characterized in that, comprises the dissolved oxygen concentration meter that measures respectively the whole dissolved oxygen concentration of above-mentioned multi-series; Sets the upper and lower limits of above-mentioned dissolved oxygen concentration , the measured dissolved oxygen concentration of each of the above multi-series series does not deviate from the upper and lower limit values to control the limiting device of the aeration air volume.

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