A segmented intelligent gas distribution control system

Abstract

The present invention discloses a segmented intelligent aeration control system, wherein the system is arranged in an aerobic tank, and the upstream of the aerobic tank is connected to the downstream of the anoxic tank; the system divides the aerobic tank into an anoxic adjustable zone, a high-efficiency aeration zone, a first regulating aeration zone, a second regulating aeration zone, and an intermittent aeration zone according to the water flow direction of the aerobic tank; a different number of pneumatic valves are provided in the five zones, and the system controls aeration of the aeration zones by opening and closing the pneumatic valves. The pneumatic valves are in aeration mode when normally open, and in stirring mode when periodically opened and closed. All pneumatic valves are connected to the blower unit. The present invention has a high degree of automation and can realize unmanned operation of the aeration system. It performs algorithmic processing on some commonly used process monitoring indicators, and can more conveniently provide more accurate biochemical tank information to operation and management personnel.

Description

Technical Field

[0001] The present invention relates to a segmented intelligent gas distribution control system, belonging to the technical field of sewage treatment. Background Art

[0002] Nowadays, with the increasing efforts in sewage treatment, the discharge requirements of sewage treatment plants have been raised several times, which has further increased the requirements for sewage treatment plant operation and management. However, there are still many deficiencies in the actual operation of sewage treatment plants that need to be optimized, especially the core biochemical treatment unit, which still has the following problems in its operation:

[0003] 1. The volume utilization rate of the biochemical pool is not high. The design of the biochemical pool is often based on the most unfavorable influent water quality of the sewage treatment plant. In most cases, the actual influent water quality of the sewage treatment plant is lower than the designed water quality. At this time, there is a lot of invalid residence time in the biochemical pool.

[0004] 2. The water inflow of sewage treatment plants fluctuates greatly, which is affected by the imperfect process control, data communication, and monitoring management of the current sewage treatment plant biochemical pool. When the sewage treatment plant faces large water quality fluctuations, it is difficult for the plant staff to make timely and correct responses.

[0005] 3. The air distribution pattern in the aeration area of ​​a biochemical pond is relatively fixed, generally following the principle of more air at the front and less air at the back. This distribution pattern provides more air to the high-pollutant concentration area at the front of the aeration zone. However, it is often difficult to manually distribute the aeration volume as designed during operation. In most cases, the majority of air is distributed to the front, indirectly resulting in greater energy loss in the front-end aeration disk. Consequently, with the same air input, the aeration system consumes more energy.

[0006] 4. The aeration system has a single control parameter. Most sewage treatment plants only control the aeration volume of the biochemical pool based on the dissolved oxygen parameter, which will lead to insufficient or excessive aeration in local aeration corridors. Summary of the Invention

[0007] The technical problems to be solved by the present invention are: low volume utilization of biochemical pools, untimely response of sewage treatment plants to water inflow fluctuations, energy loss caused by fixed air distribution methods, and single control parameters of aeration systems.

[0008] To address the above-mentioned problems, the present invention provides a segmented intelligent aeration control system, the system being arranged in an aerobic tank, the upstream of the aerobic tank being connected to the downstream of the anoxic tank. The system divides the aerobic tank into an anoxic adjustable zone, a high-efficiency aeration zone, a first regulated aeration zone, a second regulated aeration zone, and an intermittent aeration zone according to the direction of water flow in the aerobic tank. Different numbers of pneumatic valves are provided in the five zones, and the system controls aeration in the aeration zones by opening and closing the pneumatic valves. The pneumatic valves are in an aeration mode when normally open and in a stirring mode when periodically opened and closed. All pneumatic valves are arranged on aeration manifolds, which are connected to a blower unit through aeration pipes. A nitrate meter is provided upstream of the anoxic adjustable zone, a first dissolved oxygen meter is provided at the junction of the high-efficiency aeration zone and the first regulated aeration zone, a second dissolved oxygen meter is provided at the junction of the first regulated aeration zone and the second aeration regulated zone, a third dissolved oxygen meter is provided in the intermittent aeration zone, and an ammonia nitrogen water quality analyzer is provided downstream of the intermittent aeration zone.

[0009] Preferably, the ratio of the number of pneumatic valves in the anoxic adjustable zone, the high-efficiency aeration zone, the first regulating aeration zone, the second regulating aeration zone, and the intermittent aeration zone is 3:4:3:3:2.

[0010] Preferably, the aeration area and number of aeration discs controlled by each of the pneumatic valves are the same.

[0011] Preferably, a thermal mass gas flow meter is provided on the outlet pipeline of the blower group.

[0012] Preferably, the specific control strategy of the anoxic adjustable zone is as follows:

[0013] Step a): setting a baseline control value of nitrate concentration, denoted as No;

[0014] Step b): Calculate the difference N between the nitrate value actually measured by the nitrate meter and the set nitrate reference control value, that is, N=No1-No;

[0015] Step c): setting a baseline control value for ammonia nitrogen concentration in the aerobic pool, denoted as NH;

[0016] Step d): Calculate the difference H between the ammonia nitrogen value actually measured by the ammonia nitrogen water quality analyzer and the set ammonia nitrogen benchmark control value, that is, H = NH1-NH, where the value range of N is [-NH, 2NH];

[0017] Step e): Calculate the reference value A for judging the current regional operating status using the two parameters N and H according to the following formula:

[0018] A=α(N+H)-H

[0019] In the above formula: α is the system correction coefficient, α∈(0,1);

[0020] Step f): judging the overall operation mode of the anoxic adjustable zone according to the value of A. When A>0, the valve operation mode of the zone is switched to the aeration mode. When A≤0, the valve operation mode of the zone is switched to the stirring mode.

[0021] Preferably, the pneumatic valves in the high-efficiency aeration zone are all in a normally open mode.

[0022] Preferably, the specific control strategies of the first regulating aeration zone and the second regulating aeration zone are as follows:

[0023] Step g): setting a reference control value of the first dissolved oxygen meter, denoted as D1, setting a reference control value of the second dissolved oxygen meter, denoted as D2; the dissolved oxygen concentration measured by the first dissolved oxygen meter is denoted as Do1; the dissolved oxygen concentration measured by the second dissolved oxygen meter is denoted as Do2;

[0024] Step h): setting 2 / 3 of the pneumatic valves in the first regulated aeration zone to a normally open mode and the remaining pneumatic valves to a stirring mode; setting all pneumatic valves in 2 / 3 of the second regulated aeration zone to a stirring mode and the remaining pneumatic valves to a normally open mode;

[0025] Step i): Calculate the thirty-minute average of Do1 and Do2, and record it as

[0026] Step j): Calculate the difference between the dissolved oxygen mean and the set dissolved oxygen reference control value O1, O2, that is, The value range of O1 is The value range of O2 is

[0027]

[0028] Step k): The number of pneumatic valves in the two regulating aeration zones is recorded as m, and the number of pneumatic valves in the two regulating aeration zones is

[0029] Step 1): Calculate the number of pneumatic valves opened in the two areas according to the following formula based on the three values ​​of H, O1, and O2:

[0030]

[0031] In the above formula: β is the correction coefficient of the effluent ammonia nitrogen impact factor;

[0032] γ is the correction coefficient of the first dissolved oxygen meter’s influence factor;

[0033] δ is the correction coefficient of the ammonia nitrogen impact factor in the effluent of the second dissolved oxygen meter;

[0034] m is the total number of pneumatic valves in the first regulating aeration zone and the second regulating aeration zone;

[0035] Step m): Taking the opening state of the pneumatic valves in step h) as the standard state, the opening quantity of the pneumatic valves in the two areas is corrected once every 30 minutes according to the calculated C value.

[0036] Preferably, the control strategy of the intermittent aeration zone is as follows:

[0037] Step n): setting a reference control value of the third dissolved oxygen meter, denoted as D3; the dissolved oxygen concentration measured by the third dissolved oxygen meter, denoted as Do3;

[0038] Step o): Calculate the difference O3 between the actual measured dissolved oxygen value and the set dissolved oxygen reference control value, that is, O3=Do3-D3, and the value range of O3 is [-D3, D3];

[0039] Step p): setting the last pneumatic valve in the intermittent aeration zone to a stirring mode;

[0040] Step q): Number the valves in the intermittent aeration zone except the last pneumatic valve in the reverse direction of the water flow Z1, Z2, Z3...Z n ;

[0041] Step r): Create a function with the valve number as the function range and the value range of O3 as the function definition domain. The corresponding rules are:

[0042]

[0043] In the above formula: n is the number of valves in the intermittent aeration zone except the last pneumatic valve,

[0044] D3 is the reference control value for setting the third dissolved oxygen meter, mg / L;

[0045] O3 is the difference between the dissolved oxygen value and the set dissolved oxygen baseline control value, mg / L;

[0046] Step s): Based on the calculated value in step r), each pneumatic valve is judged once every 30 minutes: the valves with number subscripts less than or equal to the calculated value are set to the normally open mode, and the remaining valves are set to the stirring mode.

[0047] More preferably, the aeration rate of the blower group is determined according to the following steps:

[0048] Step t): Determine the maximum air volume of the blower in the blower group and record it as Q max , the minimum air volume is recorded as Q min , the adjustable air volume range is Q max -Q min ;

[0049] Step u): Determine the maximum number of valves to be opened in the aerobic pool F max , minimum number of open valves F min , and the number of valves involved in regulation F max -F min ;

[0050] Step v): According to the number of pneumatic valves F max -F min Determine the number of gears within the blower's air volume range, i.e., for every valve in the normally open mode, the blower's air volume is adjusted up one gear, and vice versa;

[0051] Step w): Use adjustable air volume range Q max -Q min Divide by the number of adjustable valves F max -F min Determine the adjustment range of the air volume of each blower gear, and determine the range of aeration volume according to the number of start valve openings x;

[0052] Step x): According to Do1, Do2, The changing trends of the two dissolved oxygen meter values ​​within 30 minutes were calculated respectively;

[0053] Step y): adjusting the aeration rate of the blower within a predetermined range according to the change trend to obtain a final aeration rate Q, which is calculated as follows;

[0054]

[0055] In the above formula: ε is the correction factor of the first dissolved oxygen meter to the blower,

[0056] ξ is the correction factor of the second dissolved oxygen meter for blower aeration.

[0057] Step z): Send the calculated aeration volume Q to the control cabinet of the blower. The control system of the blower itself performs frequency modulation in combination with the reading of the gas flow meter and outputs the calculated air volume.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] 1. The present invention uses pneumatic valves to re-divide the aerobic pool into functional areas, adding new functions to the original single-function aerobic pool. In the stirring mode, a localized anoxic environment is formed, achieving the removal of total nitrogen indicators in the aerobic pool;

[0060] 2. Under the control of the present invention, since the number of pneumatic valves opened is linearly related to the aeration volume of the blower unit, the actual gas flux of each aeration valve is roughly the same, thus avoiding the phenomenon of uneven gas flux between the front and rear aeration plates of the aerobic tank;

[0061] 3. The present invention divides the aerobic pool into five sections. Each section reads data from related instruments and distributes air independently to each section according to the corresponding algorithm. The blower unit uniformly supplies air based on the opening status of the valves in each area. The aeration system has a relatively rich set of control parameters, and all major parameters related to aeration are taken into consideration.

[0062] 4. The valves used in the present invention for distributing gas volume to the aeration tank are all pneumatic valves with stable performance and a price only 5% to 10% of other gas flow regulating valves;

[0063] 5. The present invention has a high degree of automation, can realize unmanned operation of the aeration system, and performs algorithm processing on some commonly used process monitoring indicators, which can more conveniently provide more accurate biochemical pool information to operation managers. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 Schematic diagram of the intelligent air distribution control system provided in Example 1;

[0065] Figure 2 Schematic diagram of the aeration pipeline in the embodiment;

[0066] Figure 3 This is a schematic layout diagram of the aeration area controlled by pneumatic valves;

[0067] Figure 4 This is a graph showing nitrogen indexes under dynamic regulation of an aerobic pool in an embodiment;

[0068] Figure 5 2 is a comparison chart of energy consumption before and after implementation in the embodiment. DETAILED DESCRIPTION

[0069] To make the present invention more clearly understood, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0070] Example 1

[0071] This embodiment provides a segmented intelligent gas distribution control system. Figure 1 Shown is a schematic diagram of the distribution of the present invention in a sewage treatment plant.

[0072] The aerobic pool is divided into five areas connected in sequence according to the direction of water flow: an anaerobic adjustable area 101, a high-efficiency aeration area 102, a first regulating aeration area 103, a second aeration regulating area 104, and an intermittent aeration area 105 (the aeration area ratio of the anaerobic adjustable area, the high-efficiency aeration area, the first regulating aeration area, the second regulating aeration area, and the intermittent aeration area is 3:4:3:3:2).

[0073] like Figure 3As shown, each area contains a different number of pneumatic valves and the number of aeration sub-areas controlled by them: the anoxic adjustable area 101 contains three aeration sub-areas in total: the first aeration sub-area 301, the second aeration sub-area 302, and the third aeration sub-area 303, which are controlled by pneumatic valve one 401, pneumatic valve two 402, and pneumatic valve three 403 respectively; the high-efficiency aeration area 102 contains four aeration sub-areas in total: the fourth aeration sub-area 304, the fifth aeration sub-area 305, the sixth aeration sub-area 306, and the seventh aeration sub-area 307, which are controlled by pneumatic valve four 404, pneumatic valve five 405, pneumatic valve six 406, and pneumatic valve seven 407 respectively; the first adjustable aeration area It includes three aeration sub-areas in total: the eighth aeration sub-area 308, the ninth aeration sub-area 309, and the tenth aeration sub-area 310, which are controlled by pneumatic valve eight 408, pneumatic valve nine 409, and pneumatic valve ten 410 respectively; the second regulating aeration zone 104 includes three aeration sub-areas in total: the eleventh aeration sub-area 311, the twelfth aeration sub-area 312, and the thirteenth aeration sub-area 313, which are controlled by pneumatic valve eleven 411, pneumatic valve twelve 412, and pneumatic valve thirteen 413 respectively; the intermittent aeration zone 105 includes two aeration sub-areas in total: the fourteenth aeration sub-area 314 and the fifteenth aeration sub-area 315, which are controlled by pneumatic valve fourteen 414 and pneumatic valve fifteen 415 respectively.

[0074] A nitrate meter 201 is set upstream of the anoxic adjustable zone 101 to measure the nitrate concentration No1 of the influent of the anoxic adjustable zone 101; a first dissolved oxygen meter 202 is set at the junction of the high-efficiency aeration zone 102 and the first regulated aeration zone 103 to measure the dissolved oxygen concentration Do1 in the area; a second dissolved oxygen meter 203 is set at the junction of the first regulated aeration zone 103 and the second aeration regulated zone 104 to measure the dissolved oxygen concentration Do2 in the area; a third dissolved oxygen meter 204 is set in the intermittent aeration zone 105 to measure the dissolved oxygen concentration Do3 in the area; and an ammonia nitrogen water quality analyzer 205 is set downstream of the intermittent aeration zone 105 to measure the ammonia nitrogen NH1 in the effluent of the aerobic tank.

[0075] Pneumatic valves are divided into two modes depending on their open / closed state: normally open mode and stirring mode. There are 15 pneumatic valves in the aerobic pool, of which four are permanently in normally open mode: pneumatic valve four 404, pneumatic valve five 405, pneumatic valve six 406, and pneumatic valve seven 407. The remaining 11 pneumatic valves are controlled by the system, which changes the pneumatic valve mode every 30 minutes based on different control strategies for each zone.

[0076] Normally open mode: the valve is always in the open state;

[0077] Agitation mode: Place the 11 valves involved in the control on a 33-minute cycle time axis. Each valve is opened and closed according to the table below. The valve is open during specific time periods and closed at other times.

[0078] Table 1 Stirring mode valve opening period table

[0079]

[0080] Control of pneumatic valves in the oxygen-deficient and oxygen-adjustable zones:

[0081] Step 1: Set the baseline control value of nitrate concentration, No = 1.0 mg / L;

[0082] Step 2: The difference N between the actual measured nitrate value and the set nitrate baseline control value, that is, N = No1-1;

[0083] Step 3: The baseline control value of ammonia nitrogen concentration in the aerobic pool is NH3 = 0.5 mg / L.

[0084] Step 4: Calculate the difference H between the actual measured ammonia nitrogen value and the set ammonia nitrogen benchmark control value, that is, N = NH1-0.5, where the value range of N is [-0.5, 1.0];

[0085] Step 5. Substitute the real-time readings of No1, NH1 and the difference between the two reference control values ​​into the original formula for calculation. In this project, α is set to 0.6, and the following formula is finally obtained:

[0086] A=0.6No1-0.4NH1-0.4

[0087] The overall operation mode of the anoxic adjustable zone is judged based on the calculated A value. When the A value is greater than 0, the mode of the zone is switched to the aeration mode. When the A value is less than or equal to 0, the mode of the zone is switched to the stirring mode.

[0088] In this embodiment, the pneumatic valve 404, the pneumatic valve 5 405, the pneumatic valve 6 406, and the pneumatic valve 7 407 of the high-efficiency aeration zone are in a normally open mode for a long time.

[0089] Valve control of the first regulating aeration zone and the second regulating aeration zone:

[0090] Step 1: Set the reference control value of the first dissolved oxygen meter, D1 = 0.8 mg / L; set the reference control value of the second dissolved oxygen meter, D2 = 1.0 mg / L;

[0091] Step 2: Set the pneumatic valve 8 408 and the pneumatic valve 10 410 in the first regulating aeration zone to a normally open mode, and the pneumatic valve 9 409 to a stirring mode. Set the pneumatic valve 12 412 in the second regulating aeration zone to a normally open mode, and the pneumatic valve 11 411 and the pneumatic valve 13 413 to a stirring mode.

[0092] Step 3: Calculate the thirty-minute average of Do1 and Do2, and record it as

[0093] Step 4: Calculate the difference between the dissolved oxygen mean and the set dissolved oxygen reference control value, O1 and O2, that is, The value range of O1 is The value range of O2 is

[0094] Step 5: The two zones control a total of 6 pneumatic valves, 3 in each zone;

[0095] Step 6: In this embodiment, the parameters in the technical solution are set as follows: β = 1.8, γ = 4, δ = 5, and the number of pneumatic valves opened in the two areas is calculated:

[0096]

[0097] Step 7. The calculated C value is the number of valves in the normally open mode in the two regulating aeration zones;

[0098] Step 8. The order in which the pneumatic valves in the two aeration adjustment zones enter the normally open mode is: pneumatic valve eight 408, pneumatic valve eleven 411, pneumatic valve ten 410, pneumatic valve eleven 411, pneumatic valve nine 409, and pneumatic valve thirteen 413.

[0099] Control of pneumatic valves in intermittent aeration zones:

[0100] Step 1: Set the reference control value of the third dissolved oxygen meter, D3 = 0.5;

[0101] Step 2: Calculate the difference O3 between the actual measured dissolved oxygen value and the set dissolved oxygen reference control value, that is, O3 = Do3-0.5, where the value range of O3 is [0, 1.0];

[0102] Step 3: Set the pneumatic valve 15 415 to the stirring mode;

[0103] Step 4: In this embodiment, n=1, and the calculation is performed according to the function created in the technical solution, and the simplified formula is obtained as follows:

[0104]

[0105] Step 5: According to the calculated value in step 5, when the calculated value is 1, the pneumatic valve 14 414 enters the normally open mode; when the calculated value is 0, the pneumatic valve 14 414 enters the stirring mode.

[0106] The aeration of the system is completed by the blower unit 501, which is composed of two blowers and a control cabinet. Figure 2 As shown, the blower unit 501 delivers air to the aerobic tank through a pipeline, and the air flow is measured by the thermal mass gas flow meter 206 on the pipeline. In this embodiment, the aeration volume of the system is adjusted every 30 minutes within the aeration range and every 15 minutes. The aeration volume adjustment strategy is as follows:

[0107] Step 1: Determine the upper and lower limits of the blower air volume. In this embodiment, the maximum air volume Q max =12000m 3 / h, minimum air volume Q min =4300m 3 / h, the adjustable air volume range is 7700m 3 / h;

[0108] Step 2: In this embodiment, the number of valves involved in the regulation is 11;

[0109] Step 3: In this embodiment, there are 11 aeration adjustment gears, and the air volume of each gear is 700m 3 / h;

[0110] Step 4: According to Do1, Do2, The changing trends of the two dissolved oxygen meter values ​​within 30 minutes are calculated using the values ​​of

[0111] Step 5: Adjust the aeration rate of the blower within a predetermined range according to the changing trend. In this embodiment, the final aeration rate Q is obtained according to the following formula:

[0112]

[0113] Where: This is the 30-minute change trend of the first dissolved oxygen meter.

[0114] This is the 30-minute change trend of the second dissolved oxygen meter.

[0115] Step 6: Send the system control air volume Q to the blower unit, and form a PID control logic between the blower unit and the thermal mass gas flow meter to adjust the system aeration volume. Figure 4This is a nitrogen index curve diagram under the dynamic regulation of the aerobic tank in this embodiment. Among the curves, the bottom green curve is the ammonia nitrogen index of the aerobic tank effluent in the embodiment; the curve with larger fluctuations at the top is the nitrate nitrogen index of the aerobic tank effluent in the embodiment; the curve with smaller fluctuations at the top is the nitrate nitrogen index of the effluent of the mirror sewage treatment production line that does not implement the present invention.

[0116] The curve shows that when the aerobic pool effluent in this embodiment is high in ammonia nitrogen, the nitrate nitrogen also reaches a high value. Specifically, when the water concentration is high, the system enhances ammonia nitrogen removal through regulation, converting more ammonia nitrogen into nitrate nitrogen. When the nitrate nitrogen is low, i.e., when the water concentration is low, the system enhances nitrate nitrogen removal through regulation. The results show that the average nitrate nitrogen content in the aerobic pool effluent in this embodiment is 5.79 mg / L, while the average nitrate nitrogen content in the aerobic pool effluent without the present invention is 7.17 mg / L. After implementing the present invention, the nitrate nitrogen content in the aerobic effluent was reduced by 1.38 mg / L.

[0117] Figure 5 This is a comparison chart of energy consumption before and after implementation in the embodiment. The implementation date is February 13. Phase three is the embodiment, and phase four is the mirror production line for comparison. The average daily energy consumption of the three phases before implementation is 3355kw, and the average daily energy consumption of the four phases is 2736kw; after production, the average daily energy consumption of the three phases is 3100kw, and the average daily energy consumption of the four phases is 2918kw; the relative energy saving ratio reaches 15.4%.

Claims

1. A segmented intelligent air distribution control system, characterized in that: The system is arranged in an aerobic tank, and the upstream of the aerobic tank is connected to the downstream of the anoxic tank; the system divides the aerobic tank into an anoxic adjustable zone, a high-efficiency aeration zone, a first regulating aeration zone, a second regulating aeration zone, and an intermittent aeration zone according to the water flow direction of the aerobic tank; different numbers of pneumatic valves are provided in the five zones, and the system controls aeration of the aeration zones by opening and closing the pneumatic valves; the pneumatic valves are in an aeration mode when normally open and in a stirring mode when periodically opened and closed; all pneumatic valves are provided on aeration branch pipes, and the aeration branch pipes are connected to the blower unit through an aeration pipe; a nitrate meter is provided upstream of the anoxic adjustable zone, a first dissolved oxygen meter is provided at the junction of the high-efficiency aeration zone and the first regulating aeration zone, a second dissolved oxygen meter is provided at the junction of the first regulating aeration zone and the second aeration regulating zone, a third dissolved oxygen meter is provided in the intermittent aeration zone, and an ammonia nitrogen water quality analyzer is provided downstream of the intermittent aeration zone; a thermal mass gas flow meter is provided on the outlet pipe of the blower unit; The specific control strategy of the anoxic adjustable zone is as follows: Step a): setting a baseline control value of nitrate concentration, denoted as No; Step b): calculating the difference N between the actually measured nitrate value and the set nitrate reference control value, that is, N=No1-No, wherein No1 is the nitrate concentration of the influent of the anoxic adjustable zone; Step c): setting a baseline control value for ammonia nitrogen concentration in the aerobic pool, denoted as NH; Step d): Calculate the difference H between the actual measured ammonia nitrogen value and the set ammonia nitrogen benchmark control value, that is, H = NH1-NH, the value range of H is [-NH, 2NH], where NH1 is the ammonia nitrogen value of the aerobic pool effluent; Step e): Calculate the reference value A for judging the current regional operating status using the two parameters N and H according to the following formula: A=α(N+H)-H In the above formula: α is the system correction coefficient, α∈(0,1); Step f): judging the overall operation mode of the anoxic adjustable zone according to the value of A. When A>0, the zone mode is switched to the aeration mode; when A≤0, the zone mode is switched to the stirring mode.

2. The segmented intelligent air distribution control system according to claim 1, characterized in that: The ratio of the number of pneumatic valves in the anoxic adjustable zone, the high-efficiency aeration zone, the first regulating aeration zone, the second regulating aeration zone, and the intermittent aeration zone is 3:4:3:3:2, and the aeration areas and the number of aeration discs controlled by the pneumatic valves are equivalent.

3. The segmented intelligent air distribution control system according to claim 1, characterized in that: The aeration area and the number of aeration discs controlled by each of the pneumatic valves are the same.

4. The segmented intelligent air distribution control system according to claim 1, characterized in that: The pneumatic valves in the high-efficiency aeration zone are all in a normally open mode.

5. The segmented intelligent air distribution control system according to claim 1, characterized in that: The specific control strategies of the first regulating aeration zone and the second regulating aeration zone are as follows: Step g): setting a reference control value of the first dissolved oxygen meter, denoted as D1, setting a reference control value of the second dissolved oxygen meter, denoted as D2; the dissolved oxygen concentration measured by the first dissolved oxygen meter is denoted as Do1; the dissolved oxygen concentration measured by the second dissolved oxygen meter is denoted as Do2; Step h): setting 2 / 3 of the pneumatic valves in the first regulating aeration zone to a normally open mode and the remaining pneumatic valves to a stirring mode; setting 2 / 3 of the pneumatic valves in the second regulating aeration zone to a stirring mode and the remaining pneumatic valves to a normally open mode; Step i): Calculate the thirty-minute average of Do1 and Do2, and record it as Step j): Calculate the difference between the dissolved oxygen mean and the set dissolved oxygen reference control value O1, O2, that is, The value range of O1 is The value range of O2 is Step k): The number of pneumatic valves in the two regulating aeration zones is recorded as m, and the number of pneumatic valves in the two regulating aeration zones is Step 1): Calculate the number of pneumatic valves opened in the two areas according to the following formula based on the three values ​​of H, O1, and O2: In the above formula: β is the correction coefficient of the effluent ammonia nitrogen impact factor; γ is the correction coefficient of the first dissolved oxygen meter’s influence factor; δ is the correction coefficient of the impact factor of the second dissolved oxygen meter; m is the total number of pneumatic valves in the first regulating aeration zone and the second regulating aeration zone; Step m): Taking the valve opening condition in step h) as the standard state, the valve opening quantity is corrected every 30 minutes according to the calculated C value.

6. The segmented intelligent air distribution control system according to claim 1, characterized in that: The control strategy of the intermittent aeration zone is as follows: Step n): setting a reference control value of the third dissolved oxygen meter, denoted as D3; the dissolved oxygen concentration measured by the third dissolved oxygen meter, denoted as Do3; Step o): Calculate the difference O3 between the actual measured dissolved oxygen value and the set dissolved oxygen reference control value, that is, O3=Do3-D3, and the value range of O3 is [-D3, D3]; Step p): setting the last pneumatic valve in the intermittent aeration zone to a stirring mode; Step q): Number the valves in the intermittent aeration zone except the last pneumatic valve in the reverse direction of the water flow Z1, Z2, Z3...Z n ; Step r): Create a function with the valve number as the function range and the value range of O3 as the function definition domain. The corresponding rules are: In the above formula: n is the number of valves in the intermittent aeration zone except the last pneumatic valve, D3 is the reference control value for setting the third dissolved oxygen meter, mg / L; O3 is the difference between the dissolved oxygen value and the set dissolved oxygen baseline control value, mg / L; Step s): According to the calculated value in step r), every 30 minutes, the valves with subscripts less than or equal to the calculated value are set to the normally open mode, and the remaining valves are set to the stirring mode.

7. The segmented intelligent air distribution control system according to claim 5, characterized in that: The aeration rate of the blower group is determined according to the following steps: Step t): Determine the maximum air volume of the blower in the blower group and record it as Q max , the minimum air volume is recorded as Q min , the adjustable air volume range is Q max -Q min ; Step u): Determine the maximum number of valves to be opened in the aerobic pool F max , minimum number of open valves F min , and the number of valves involved in regulation F max -F min ; Step v): According to the number of pneumatic valves F max -F min Determine the number of gears within the blower's air volume range, i.e., for every valve in the normally open mode, the blower's air volume is adjusted up one gear, and vice versa; Step w): Use adjustable air volume range Q max -Q min Divide by the number of adjustable valves F max -F min Determine the adjustment range of the air volume of each blower gear, and determine the range of aeration volume according to the number of start valve openings x; Step x): According to Do1, Do2, The changing trends of the two dissolved oxygen meter values ​​within 30 minutes were calculated respectively; Step y): Adjust the aeration volume of the blower within a predetermined range according to the change trend to obtain the final aeration volume Q. The calculation method of Q is as follows: In the above formula: ε is the correction factor of the first dissolved oxygen meter to the blower; ζ is the correction factor of the second dissolved oxygen meter for the blower aeration; Step z): Send the calculated aeration volume Q to the control cabinet of the blower. The control system of the blower itself performs frequency modulation in combination with the reading of the gas flow meter and outputs the calculated air volume.

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