A wastewater treatment system and control method

Abstract

This application relates to the field of wastewater treatment technology, specifically to a wastewater treatment system and control method. The wastewater treatment system includes a wastewater treatment zone, a first analysis unit, a second analysis unit, an aeration unit, an external carbon source dosing unit, and a control unit. The aeration unit is connected to the aerobic zone and is used to introduce air into the aerobic zone. The external carbon source dosing unit is connected to the anoxic zone and is used to introduce an external carbon source into the anoxic zone. The control unit is used to control the amount of air introduced into the aerobic zone by the aeration unit. The control unit is also used to control the amount of external carbon source introduced into the anoxic zone by the external carbon source dosing unit based on the ammonia nitrogen and nitrate nitrogen parameters of the aerobic zone. This wastewater treatment system can achieve on-demand aeration in the biochemical aerobic stage according to the actual wastewater treatment situation, maximizing energy savings in aeration and external carbon source dosing. Simultaneously, it enables unattended management of the wastewater treatment plant, significantly saving management manpower.

Description

Technical Field

[0001] This application relates to the field of wastewater treatment technology, and more specifically, to a wastewater treatment system and control method. Background Technology

[0002] Currently, wastewater treatment plant control largely relies on PLC systems and computer management to automate wastewater treatment operations, eliminating manual intervention and enabling real-time monitoring and management of the treatment site. For example, using dissolved oxygen as a control parameter, blowers and valves act as actuators to regulate dissolved oxygen levels in the aerobic tank. However, in practical applications, the control effect is poor, energy and chemical consumption savings fail to meet user needs, and microorganisms within the biological system cannot function optimally. Furthermore, the advent of smart city and low-carbon goals necessitates "unmanned" wastewater treatment plants. To achieve unmanned operation, the core requirements are high-quality wastewater treatment facilities and operation management, high-quality testing instruments, and a high-level automated control system. Summary of the Invention

[0003] This application provides a wastewater treatment system and control method to improve the above-mentioned problems.

[0004] The present invention is as follows:

[0005] A wastewater treatment system includes a wastewater treatment zone, a first analysis unit, a second analysis unit, an aeration unit, an external carbon source dosing unit, and a control unit;

[0006] The wastewater treatment zones include anaerobic, anoxic, and aerobic zones, which are sequentially connected.

[0007] The first analysis unit is used to detect the water quality parameters of the water entering and exiting the wastewater treatment zone; the second analysis unit is located in the aerobic zone and is used to detect the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the aerobic zone; the aeration unit is connected to the aerobic zone and is used to introduce air into the aerobic zone; the external carbon source addition unit is connected to the anoxic zone and is used to introduce external carbon sources into the anoxic zone.

[0008] The first analysis unit, the second analysis unit, the aeration unit, and the external carbon source dosing unit are all electrically connected to the control unit. The control unit is used to control the amount of air introduced into the aerobic zone by the aeration unit based on the parameters of ammonia nitrogen, nitrate nitrogen, and dissolved oxygen in the aerobic zone, as well as the water quality parameters of the water introduced into the wastewater treatment zone. The control unit is also used to control the amount of external carbon source introduced into the anoxic zone by the external carbon source dosing unit based on the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone, as well as the water quality parameters of the water introduced into the wastewater treatment zone.

[0009] In one embodiment of the present invention, the aerobic zone includes a pulse aeration zone, a steady-state aerobic zone, and a transition zone. The transition zone is located between the pulse aeration zone and the steady-state aerobic zone, and is connected to both the pulse aeration zone and the steady-state aerobic zone.

[0010] The second analysis unit is located in the transition zone and is used to detect the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the transition zone; the aeration unit is connected to the pulse aeration zone and the steady-state aerobic zone and is used to introduce air into the pulse aeration zone and the steady-state aerobic zone.

[0011] The control unit is used to control the amount of air introduced into the pulse aeration zone and steady-state aerobic zone by the aeration unit based on the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the transition zone and the water quality parameters of the water introduced into the wastewater treatment zone.

[0012] In one embodiment of the present invention, the residence time of wastewater in the pulse aeration zone is 2-4 times that of wastewater in the steady-state aerobic zone.

[0013] In one embodiment of the present invention, the aeration unit includes a blower, a first air inlet pipe, a second air inlet pipe, a first air flow regulating valve, and a second air flow regulating valve;

[0014] The two ends of the first air inlet pipe are connected to the fan and the pulse aeration zone, respectively. The two ends of the second air inlet pipe are connected to the fan and the steady-state aerobic zone, respectively. The first air flow regulating valve and the second air flow regulating valve are respectively installed in the first air inlet pipe and the second air inlet pipe.

[0015] The fan, the first air flow regulating valve, and the second air flow regulating valve are all electrically connected to the control unit.

[0016] In one embodiment of the present invention, the wastewater treatment system further includes a nitrification liquid recirculation unit, which connects the anoxic zone and the aerobic zone and is used to introduce the nitrification liquid from the aerobic zone into the anoxic zone.

[0017] The nitrification liquid recirculation unit is electrically connected to the control unit. The control unit is also used to control the nitrification liquid recirculation ratio from the aerobic zone to the anoxic zone based on the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone and the water quality parameters of the water exported from the wastewater treatment zone.

[0018] In one embodiment of the present invention, the wastewater treatment zone further includes an inlet pipe, a secondary sedimentation tank, and an outlet pipe; the inlet pipe is connected to the anaerobic zone to introduce wastewater into the anaerobic zone; the secondary sedimentation tank is connected to the aerobic zone, and the outlet pipe is connected to the secondary sedimentation tank to discharge water from the secondary sedimentation tank.

[0019] The first analysis unit includes a first water quality detector, a second water quality detector, a first flow meter, and a second flow meter; the first water quality detector and the first flow meter are installed in the inlet pipe and are used to detect the water quality and flow rate of the sewage introduced into the sewage treatment zone through the inlet pipe; the second water quality detector and the second flow meter are installed in the outlet pipe and are used to detect the water quality and flow rate of the water treated by the sewage treatment zone discharged from the outlet pipe.

[0020] A wastewater treatment control method, implemented using the aforementioned wastewater treatment system, includes:

[0021] Receives the first detection signal from the first analysis unit, which characterizes the water quality parameters of the imported and exported wastewater treatment zones; receives the second detection signal from the second analysis unit, which characterizes the ammonia nitrogen, nitrate nitrogen, and dissolved oxygen parameters of the aerobic zone;

[0022] The amount of air introduced into the aeration unit from the aeration zone is controlled based on the parameters of ammonia nitrogen, nitrate nitrogen, and dissolved oxygen in the aerobic zone, as well as the water quality parameters of the water introduced into the wastewater treatment zone.

[0023] Based on the ammonia nitrogen and nitrate nitrogen parameters of the aerobic zone, and the water quality parameters of the wastewater treatment zone, the amount of external carbon source introduced into the anoxic zone by the external carbon source addition unit and the nitrification liquid return ratio introduced from the aerobic zone to the anoxic zone by the nitrification liquid return unit are controlled.

[0024] In one embodiment of the present invention, prior to the step of controlling the air intake of the aeration unit into the aerobic zone, the wastewater treatment control method further includes:

[0025] The simulated oxygen demand and corresponding gas supply for the aerobic zone were calculated based on the embedded biochemical model, as follows:

[0026]

[0027]

[0028]

[0029]

[0030]

[0031] In the formula, r COD Y represents the COD removal rate; H μ is the yield coefficient of heterotrophic microorganisms. H C represents the maximum specific proliferation rate of heterotrophic microorganisms. COD COD concentration; C O2 O2 concentration; X H For heterotrophic microorganism concentration; k COD k is the COD half-saturation constant.O2 C is the half-saturation constant of O2. NO3-N NO3-N concentration; η is the denitrification coefficient; r NH3-N Y represents the NH3-N removal rate. A μ is the autotrophic microbial yield coefficient. A C represents the maximum specific growth rate of autotrophic microorganisms. NH3-N X represents the concentration of NH3-N. A For autotrophic microbial concentration; k NH3-N k is the half-saturation constant of NH3-N. OA r is the half-saturation constant of nitrifying bacteria. NO3-N r represents the NO3-N removal rate. O2 Q represents the rate of O2 consumption. air α is the aeration flow rate; E is the oxygenation coefficient; A This refers to the oxygen transfer rate.

[0032] In one embodiment of the present invention, the step of controlling the air intake of the aeration unit into the aerobic zone includes:

[0033] Based on the simulated oxygen demand and corresponding air supply in the aerobic zone, the amount of air introduced into the pulse aeration zone and the steady-state aerobic zone by the aeration unit is determined.

[0034] The aeration unit controls the introduction of air into the pulse aeration zone and the steady-state aerobic zone;

[0035] The steps for determining the amount of air introduced into the pulse aeration zone by the aeration unit are as follows:

[0036]

[0037] In the formula, M is the pulse coefficient; f k t represents the pulse control period; [NH3-N] * These are the parameters for ammonia nitrogen and nitrate nitrogen in the aerobic zone; Δ is the control value, ranging from 3 to 8.

[0038] In one embodiment of the present invention, before the steps of controlling the amount of external carbon source introduced into the anoxic zone by the external carbon source addition unit and the nitrification liquid recirculation ratio introduced from the aerobic zone into the anoxic zone by the nitrification liquid recirculation unit, the wastewater treatment control method further includes:

[0039] The preset nitrification liquor recirculation ratio for the aerobic zone to the anoxic zone in the nitrification liquor recirculation unit is determined as follows:

[0040]

[0041] In the formula, Q in Δ represents the inlet water volume; Δ is the set control point value, ranging from 3 to 8.

[0042] The external carbon sources added to the anoxic zone by the external carbon source addition unit are determined as follows:

[0043]

[0044] In the formula, β is the dosage coefficient; [NO3-N]2 is the nitrate value in the water quality parameters of the wastewater treatment zone; and N is the effluent standard TN value.

[0045] The beneficial effects of this invention include:

[0046] The wastewater treatment system

[0047] The wastewater treatment system includes a wastewater treatment zone, a first analysis unit, a second analysis unit, an aeration unit, an external carbon source dosing unit, and a control unit. The wastewater treatment zone includes an anaerobic zone, an anoxic zone, and an aerobic zone, which are sequentially connected. The first analysis unit is used to detect the water quality parameters of the water entering and leaving the wastewater treatment zone. The second analysis unit is located in the aerobic zone and is used to detect the parameters of ammonia nitrogen, nitrate nitrogen, and dissolved oxygen in the aerobic zone. The aeration unit is connected to the aerobic zone and is used to introduce air into the aerobic zone. The external carbon source dosing unit is connected to the anoxic zone and is used to introduce an external carbon source into the anoxic zone. The first analysis unit, the second analysis unit, the aeration unit, and the external carbon source dosing unit are all electrically connected to the control unit. The control unit is used to control the amount of air introduced into the aerobic zone by the aeration unit based on the parameters of ammonia nitrogen, nitrate nitrogen, and dissolved oxygen in the aerobic zone and the water quality parameters of the water entering the wastewater treatment zone. The control unit is also used to control the amount of external carbon source introduced into the anoxic zone by the external carbon source dosing unit based on the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone and the water quality parameters of the water leaving the wastewater treatment zone. This wastewater treatment system can perform on-demand aeration during the biochemical aerobic stage according to the actual wastewater treatment situation, maximizing energy savings in aeration and external carbon source addition; at the same time, it can achieve unattended management of the wastewater treatment plant, greatly saving human resources for management. Attached Figure Description

[0048] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 This is a structural schematic diagram of the wastewater treatment system provided in this application;

[0050] Figure 2 A schematic diagram of the water and electricity consumption per ton before and after implementation A in this application.

[0051] Icons: 200 - Wastewater treatment system; 110 - Wastewater treatment zone; 120 - First analysis unit; 130 - Second analysis unit; 140 - Aeration unit; 150 - External carbon source addition unit; 160 - Control unit; 141 - Blower; 142 - First air inlet pipe; 143 - Second air inlet pipe; 144 - First air flow regulating valve; 145 - Second air flow regulating valve; 170 - Nitrification liquid reflux unit; 111 - Inlet pipe; 112 - Outlet pipe; 121 - First water quality detector; 122 - Second water quality detector. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0053] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0054] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0055] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0056] In the description of the embodiments of this application, it should be noted that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use, or the orientation or positional relationship commonly understood by those skilled in the art, and is only for the convenience of describing this application and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. In addition, the terms "first," "second," "third," etc. are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0057] In the description of the embodiments of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0058] Please refer to Figure 1 This embodiment provides a wastewater treatment system 200, including a wastewater treatment zone 110, a first analysis unit 120, a second analysis unit 130, an aeration unit 140, an external carbon source dosing unit 150, and a control unit 160;

[0059] Wastewater treatment zone 110 includes an anaerobic zone (such as...) Figure 1 (as shown by the mark A in the middle), hypoxia zone (such as...) Figure 1 (as shown by the mark B) and aerobic zone (as shown by the mark B) Figure 1 As shown by the mark C in the middle, the anaerobic zone, the anoxic zone, and the aerobic zone are connected in sequence;

[0060] The first analysis unit 120 is used to detect the water quality parameters of the water entering and exiting the wastewater treatment zone 110; the second analysis unit 130 is set in the aerobic zone and is used to detect the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the aerobic zone; the aeration unit 140 is connected to the aerobic zone and is used to introduce air into the aerobic zone; the external carbon source addition unit 150 is connected to the anoxic zone and is used to introduce an external carbon source into the anoxic zone.

[0061] The first analysis unit 120, the second analysis unit 130, the aeration unit 140, and the external carbon source addition unit 150 are all electrically connected to the control unit 160. The control unit 160 is used to control the amount of air introduced into the aerobic zone by the aeration unit 140 based on the parameters of ammonia nitrogen, nitrate nitrogen, and dissolved oxygen in the aerobic zone, as well as the water quality parameters of the water introduced into the wastewater treatment zone 110. The control unit 160 is also used to control the amount of external carbon source introduced into the anoxic zone by the external carbon source addition unit 150 based on the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone, as well as the water quality parameters of the water exported from the wastewater treatment zone 110.

[0062] Please refer to Figure 1 The working principle of this wastewater treatment system 200 is as follows:

[0063] The wastewater treatment system 200 includes a wastewater treatment zone 110, a first analysis unit 120, a second analysis unit 130, an aeration unit 140, an external carbon source dosing unit 150, and a control unit 160. The wastewater treatment zone 110 includes an anaerobic zone, an anoxic zone, and an aerobic zone, which are sequentially connected. The treatment process of the wastewater in the anaerobic zone, anoxic zone, and aerobic zone is the same as that in the prior art, and therefore will not be described in detail here.

[0064] The aeration unit 140 is connected to the aerobic zone to introduce air into the aerobic zone; the external carbon source addition unit 150 is connected to the anoxic zone to introduce an external carbon source into the anoxic zone.

[0065] Therefore, during the wastewater treatment process, the wastewater treatment system 200 can detect the water quality parameters of the water entering and exiting the wastewater treatment zone 110 through the first analysis unit 120; and can detect the parameters of ammonia nitrogen, nitrate nitrogen, and dissolved oxygen in the aerobic zone through the second analysis unit 130. Furthermore, the control unit 160 can collect the detection data output by the first analysis unit 120 and the second analysis unit 130, and analyze them to obtain the water quality parameters of the water entering the wastewater treatment zone 110, the water quality parameters of the water exiting the wastewater treatment zone 110, the parameters of ammonia nitrogen in the aerobic zone, the parameters of nitrate nitrogen in the aerobic zone, and the parameters of dissolved oxygen in the aerobic zone. Thus, the control unit 160 can control the amount of air introduced into the aerobic zone by the aeration unit 140 and the amount of external carbon source introduced into the anoxic zone by the external carbon source addition unit 150 through the analysis of the aforementioned parameters.

[0066] In summary, the wastewater treatment system 200 can achieve on-demand aeration in the aerobic stage of biochemical treatment according to the actual wastewater treatment situation, maximizing the saving of aeration energy consumption and external carbon source addition. It can also control the amount of external carbon source introduced into the anoxic zone by the external carbon source addition unit 150. At the same time, by collecting and analyzing the relevant data collected by the first analysis unit 120 and the second analysis unit 130 during operation, it can realize unattended management of the wastewater treatment plant, greatly saving human resources for management.

[0067] Further, please refer to Figure 1 In this embodiment, the aerobic zone includes a pulse aeration zone (such as...). Figure 1 (as shown by the mark D in the middle), steady-state aerobic zone (such as...) Figure 1 (as indicated by the mark E in the middle) and the transition zone, which is located between the pulse aeration zone and the steady-state aerobic zone, and is connected to both the pulse aeration zone and the steady-state aerobic zone;

[0068] The second analysis unit 130 is located in the transition zone and is used to detect the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the transition zone; the aeration unit 140 is connected to the pulse aeration zone and the steady-state aerobic zone and is used to introduce air into the pulse aeration zone and the steady-state aerobic zone.

[0069] The control unit 160 is used to control the amount of air introduced into the pulse aeration zone and the steady-state aerobic zone by the aeration unit 140 based on the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the transition zone and the water quality parameters of the water introduced into the wastewater treatment zone 110.

[0070] Moreover, the residence time of wastewater in the pulse aeration zone is 2-4 times that of wastewater in the steady-state aerobic zone.

[0071] When setting up the aeration unit 140, the aeration unit 140 includes a blower 141, a first air inlet pipe 142, a second air inlet pipe 143, a first air flow regulating valve 144, and a second air flow regulating valve 145.

[0072] The two ends of the first air inlet pipe 142 are connected to the fan 141 and the pulse aeration zone, respectively. The two ends of the second air inlet pipe 143 are connected to the fan 141 and the steady-state aerobic zone, respectively. The first air flow regulating valve 144 and the second air flow regulating valve 145 are respectively installed on the first air inlet pipe 142 and the second air inlet pipe 143.

[0073] Among them, the fan 141, the first air flow regulating valve 144 and the second air flow regulating valve 145 are all electrically connected to the control unit 160.

[0074] Therefore, by controlling the working state of the blower 141 and adjusting the opening of the first air flow regulating valve 144 and the second air flow regulating valve 145, on-demand aeration in the biochemical aerobic stage can be achieved.

[0075] In addition, please refer to Figure 1 In this embodiment, the wastewater treatment system 200 further includes a nitrification liquid return unit 170, which connects the anoxic zone and the aerobic zone and is used to introduce the nitrification liquid from the aerobic zone into the anoxic zone.

[0076] The nitrification liquor recirculation unit 170 is electrically connected to the control unit 160. The control unit 160 is also used to control the nitrification liquor recirculation ratio from the aerobic zone to the anoxic zone based on the ammonia nitrogen and nitrate nitrogen parameters of the aerobic zone and the water quality parameters of the water exported from the wastewater treatment zone 110. Therefore, by rationally controlling the external carbon source and the nitrification liquor recirculation ratio, the amount of external carbon source added can be reduced, resulting in savings of more than 50% in external carbon source addition.

[0077] When setting up the first analysis unit 120 and the second powder box unit, the wastewater treatment zone 110 also includes an inlet pipe 111 and a secondary sedimentation tank (such as...). Figure 1 (as indicated by F in the middle) and outlet pipe 112; inlet pipe 111 is connected to the anaerobic zone to introduce sewage into the anaerobic zone; secondary sedimentation tank is connected to the aerobic zone, and outlet pipe 112 is connected to the secondary sedimentation tank to discharge water from the secondary sedimentation tank.

[0078] The first analysis unit 120 includes a first water quality detector 121, a second water quality detector 122, a first flow meter, and a second flow meter. The first water quality detector 121 and the first flow meter are installed in the inlet pipe 111 and are used to detect the water quality and flow rate of the wastewater introduced into the wastewater treatment zone 110 through the inlet pipe 111. The second water quality detector 122 and the second flow meter are installed in the outlet pipe 112 and are used to detect the water quality and flow rate of the water treated by the wastewater treatment zone 110 exiting through the outlet pipe 112. It should be noted that when setting the first water quality detector 121 and the second water quality detector 122, the types of substances in the wastewater that the first water quality detector 121 and the second water quality detector 122 can detect can be adjusted according to the usage requirements.

[0079] Based on the above, please refer to Figure 1 This embodiment also provides a wastewater treatment control method, implemented using the aforementioned wastewater treatment system 200, including:

[0080] The system receives a first detection signal from the first analysis unit 120, which characterizes the water quality parameters of the imported and exported wastewater treatment zone 110; and receives a second detection signal from the second analysis unit 130, which characterizes the ammonia nitrogen, nitrate nitrogen, and dissolved oxygen parameters of the aerobic zone.

[0081] Based on the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the aerobic zone, and the water quality parameters of the water introduced into the wastewater treatment zone 110, the amount of air introduced into the aerobic zone by the aeration unit 140 is controlled.

[0082] Based on the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone, and the water quality parameters of the water in the wastewater treatment zone 110, the amount of external carbon source introduced into the anoxic zone by the external carbon source addition unit 150 and the nitrification liquid return ratio introduced from the aerobic zone to the anoxic zone by the nitrification liquid return unit 170 are controlled.

[0083] Furthermore, prior to the step of controlling the air intake of the aeration unit 140 into the aerobic zone, the wastewater treatment control method also includes:

[0084] The simulated oxygen demand and corresponding gas supply for the aerobic zone were calculated based on the embedded biochemical model, as follows:

[0085]

[0086]

[0087]

[0088]

[0089]

[0090] In the formula, r COD Y represents the COD removal rate; H μ is the yield coefficient of heterotrophic microorganisms. H C represents the maximum specific proliferation rate of heterotrophic microorganisms. COD COD concentration; C O2 O2 concentration; X H For heterotrophic microorganism concentration; k COD k is the COD half-saturation constant. O2 C is the half-saturation constant of O2. NO3-N NO3-N concentration; η is the denitrification coefficient; r NH3-N Y represents the NH3-N removal rate. A μ is the autotrophic microbial yield coefficient. A C represents the maximum specific growth rate of autotrophic microorganisms. NH3-N X represents the concentration of NH3-N. A For autotrophic microbial concentration; k NH3-N k is the half-saturation constant of NH3-N. OA r is the half-saturation constant of nitrifying bacteria. NO3-N r represents the NO3-N removal rate. O2 Q represents the rate of O2 consumption. air α is the aeration flow rate; E is the oxygenation coefficient; A This refers to the oxygen transfer rate.

[0091] Since the aerobic zone in the aforementioned wastewater treatment system 200 includes a pulse aeration zone, a steady-state aerobic zone, and a transition zone, the step of controlling the air intake of the aeration unit 140 into the aerobic zone includes:

[0092] Based on the simulated oxygen demand and corresponding air supply of the aerobic zone, the amount of air introduced into the pulse aeration zone and the steady-state aerobic zone by the aeration unit 140 is determined.

[0093] Control the aeration unit 140 to introduce air into the pulse aeration zone and the steady-state aerobic zone;

[0094] The steps for determining the amount of air introduced into the pulse aeration zone by the aeration unit 140 are as follows:

[0095]

[0096] In the formula, M is the pulse coefficient; f k t represents the pulse control period; [NH3-N] *These are the parameters for ammonia nitrogen and nitrate nitrogen in the aerobic zone; Δ is the control value, ranging from 3 to 8.

[0097] Furthermore, prior to the steps of controlling the amount of external carbon source introduced into the anoxic zone by the external carbon source addition unit 150 and the nitrification liquor recirculation ratio introduced from the aerobic zone to the anoxic zone by the nitrification liquor recirculation unit 170, the wastewater treatment control method also includes:

[0098] The preset nitrification liquor recirculation ratio for the nitrification liquor recirculation unit 170, from the aerobic zone to the anoxic zone, is determined as follows:

[0099]

[0100] In the formula, Q in Δ represents the inlet water volume; Δ is the set control point value, ranging from 3 to 8.

[0101] The external carbon source to be added to the anoxic zone by external carbon source addition unit 150 is determined as follows:

[0102]

[0103] In the formula, β is the addition coefficient; [NO3-N]2 is the nitrate value in the water quality parameters of wastewater treatment zone 110; N is the effluent standard TN value.

[0104] In summary, the wastewater treatment system 200 and wastewater treatment control methods described above enable intelligent control of the wastewater treatment process, thereby improving the operating efficiency of the wastewater treatment system 200 and reducing labor costs during operation. Furthermore, during operation, the embedded synchronous nitrification-denitrification biochemical model allows for the determination of reasonable operating control parameters based on influent water quality and ammonia nitrogen parameters at control points. The addition of ammonia nitrogen detection instruments in the aerobic tank of the biochemical process, using ammonia nitrogen as the control parameter, enables on-demand aeration during the aerobic stage, maximizing energy savings of over 10%. By adjusting the external carbon source and nitrification liquid return ratio, the external carbon source dosage can be reduced by over 50%. Specifically, the following embodiments are provided.

[0105] Example A:

[0106] When the residence time of wastewater in the pulse aeration zone is four times that in the steady-state aerobic zone, the control unit 160 acquires data from the first analysis unit 120 and the second analysis unit 130, and calculates the simulated oxygen demand and corresponding air supply based on the embedded biochemical model. The iterative algorithm is as follows:

[0107]

[0108]

[0109]

[0110]

[0111]

[0112] In the formula, r COD Y represents the COD removal rate; H μ is the yield coefficient of heterotrophic microorganisms. H C represents the maximum specific proliferation rate of heterotrophic microorganisms. COD COD concentration; C O2 O2 concentration; X H For heterotrophic microorganism concentration; k COD k is the COD half-saturation constant. O2 C is the half-saturation constant of O2. NO3-N NO3-N concentration; η is the denitrification coefficient; r NH3-N Y represents the NH3-N removal rate. A μ is the autotrophic microbial yield coefficient. A C represents the maximum specific growth rate of autotrophic microorganisms. NH3-N X represents the concentration of NH3-N. A For autotrophic microbial concentration; k NH3-N k is the half-saturation constant of NH3-N. OA r is the half-saturation constant of nitrifying bacteria. NO3-N r represents the NO3-N removal rate. O2 Q represents the rate of O2 consumption. air α is the aeration flow rate; E is the oxygenation coefficient; A This refers to the oxygen transfer rate.

[0113] Based on data from the online ammonia nitrogen analyzer, the control algorithm for the pulse aeration zone, according to the simulated oxygen demand and pulse air supply mode, is as follows:

[0114]

[0115] In the formula, M is the pulse coefficient; f k t represents the pulse control period; [NH3-N] * The parameters for ammonia nitrogen and nitrate nitrogen in the aerobic zone; Δ is the control value, which is 7.

[0116] In this embodiment, the control algorithm for the amount of external carbon source added is as follows:

[0117]

[0118] In the formula, β is the addition coefficient, which takes the value of 4; [NO3-N]2 is used to derive the nitrate value in the water quality parameters of wastewater treatment zone 110; N is the effluent standard TN value, which is 15 mg / L.

[0119] The control algorithm for the nitrification liquor reflux ratio is as follows:

[0120]

[0121] In the formula, Q in Δ represents the inlet water volume, and Δ is the set control point value, which is 7.

[0122] The average weekly power consumption per ton of water before and after implementation is as follows: Figure 2 As shown, the electricity consumption before implementation was 0.39 kWh / t, and after implementation it was 0.34 kWh / t, resulting in a 12.8% reduction in energy consumption per ton of water.

[0123] Example B:

[0124] When the residence time of wastewater in the pulse aeration zone is three times that in the steady-state aerobic zone, the control unit 160 acquires data from the first analysis unit 120 and the second analysis unit 130, and calculates the simulated oxygen demand and corresponding air supply based on the embedded biochemical model. The iterative algorithm is as follows:

[0125]

[0126]

[0127]

[0128]

[0129]

[0130] In the formula, r COD Y represents the COD removal rate; H μ is the yield coefficient of heterotrophic microorganisms. H C represents the maximum specific proliferation rate of heterotrophic microorganisms. COD COD concentration; C O2 O2 concentration; X H For heterotrophic microorganism concentration; k COD k is the COD half-saturation constant. O2 C is the half-saturation constant of O2. NO3-N NO3-N concentration; η is the denitrification coefficient; r NH3-N Y represents the NH3-N removal rate. A μ is the autotrophic microbial yield coefficient. A C represents the maximum specific growth rate of autotrophic microorganisms. NH3-N X represents the concentration of NH3-N. A For autotrophic microbial concentration; k NH3-N k is the half-saturation constant of NH3-N. OAr is the half-saturation constant of nitrifying bacteria. NO3-N r represents the NO3-N removal rate. O2 Q represents the rate of O2 consumption. air α is the aeration flow rate; E is the oxygenation coefficient; A This refers to the oxygen transfer rate.

[0131] The aeration mode of the pulse aeration zone is based on the simulated oxygen demand and the pulse air supply mode, and its control algorithm is as follows:

[0132]

[0133] In the formula, M is the pulse coefficient; f k t represents the pulse control period; [NH3-N] * These are the parameters for ammonia nitrogen and nitrate nitrogen in the aerobic zone; Δ is the control value, which is 5.

[0134] In this embodiment, the control algorithm for the amount of external carbon source added is as follows:

[0135]

[0136] In the formula, β is the addition coefficient, which takes the value of 4; [NO3-N]2 is the nitrate value in the water quality parameters of wastewater treatment zone 110; N is the effluent standard TN value, which is 15 mg / L.

[0137] The control algorithm for the nitrification liquor reflux ratio is as follows:

[0138]

[0139] In the formula, Q in Δ represents the inlet water volume, and Δ is the set control point value, which is 5.

[0140] The average weekly electricity consumption per ton of water before and after implementation was 0.27 kWh / t before implementation and 0.24 kWh / t after implementation, resulting in a 13% reduction in energy consumption per ton of water. The amount of external carbon source added per ton of water before implementation was 60 mg / L, and after implementation it was 30 mg / L, resulting in a 50% reduction in the amount of external carbon source added per ton of water.

[0141] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A sewage treatment system, characterized in that: the sewage treatment system comprises a sewage treatment partition, a first analysis unit, a second analysis unit, an aeration unit, an external carbon source adding unit and a control unit; the sewage treatment partition comprises an anaerobic zone, an anoxic zone and an aerobic zone, and the anaerobic zone, the anoxic zone and the aerobic zone are sequentially communicated; the first analysis unit is used for detecting the water quality parameters of water introduced into and discharged from the sewage treatment partition; the second analysis unit is arranged in the aerobic zone and is used for detecting the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the aerobic zone; the aeration unit is communicated with the aerobic zone and is used for introducing air into the aerobic zone; the external carbon source adding unit is communicated with the anoxic zone and is used for introducing an external carbon source into the anoxic zone; the first analysis unit, the second analysis unit, the aeration unit and the external carbon source adding unit are electrically connected with the control unit; the control unit is used for controlling the air amount introduced into the aerobic zone by the aeration unit according to the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the aerobic zone and the water quality parameters of water introduced into the sewage treatment partition; and the control unit is also used for controlling the external carbon source amount introduced into the anoxic zone by the external carbon source adding unit according to the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone and the water quality parameters of water discharged from the sewage treatment partition; the aerobic zone comprises a pulse aeration zone, a steady-state aerobic zone and a transition region, the transition region is located between the pulse aeration zone and the steady-state aerobic zone, and the transition region is communicated with the pulse aeration zone and the steady-state aerobic zone; the second analysis unit is arranged in the transition region and is used for detecting the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the transition region; the aeration unit is communicated with the pulse aeration zone and the steady-state aerobic zone and is used for introducing air into the pulse aeration zone and the steady-state aerobic zone; and the control unit is used for controlling the air amount introduced into the pulse aeration zone and the steady-state aerobic zone by the aeration unit according to the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the transition region and the water quality parameters of water introduced into the sewage treatment partition. 2.The sewage treatment system according to claim 1, characterized in that: the residence time of sewage in the pulse aeration zone is 2-4 times the residence time of sewage in the steady-state aerobic zone. 3.The sewage treatment system according to claim 1, characterized in that: the aeration unit comprises a fan, a first air inlet pipe, a second air inlet pipe, a first air flow regulating valve and a second air flow regulating valve; two ends of the first air inlet pipe are respectively communicated with the fan and the pulse aeration zone, two ends of the second air inlet pipe are respectively communicated with the fan and the steady-state aerobic zone, and the first air flow regulating valve and the second air flow regulating valve are arranged in the first air inlet pipe and the second air inlet pipe respectively; and the fan, the first air flow regulating valve and the second air flow regulating valve are electrically connected with the control unit. 4.The sewage treatment system according to any one of claims 1-3, characterized in that: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The sewage treatment system further comprises a nitrification liquid reflux unit, which is in communication with the anoxic zone and the aerobic zone and is used to guide nitrification liquid in the aerobic zone into the anoxic zone. The nitrification liquid reflux unit is electrically connected with the control unit, and the control unit is further used to control the nitrification liquid reflux ratio of the nitrification liquid guided from the aerobic zone into the anoxic zone according to the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone and the water quality parameters of the water guided out of the sewage treatment partition.

5. The sewage treatment system according to any one of claims 1-3, characterized in that: The sewage treatment partition further comprises an inlet pipe, a secondary sedimentation tank and an outlet pipe; the inlet pipe is in communication with the anaerobic zone to guide sewage into the anaerobic zone; the secondary sedimentation tank is in communication with the aerobic zone, and the outlet pipe is in communication with the secondary sedimentation tank to guide water in the secondary sedimentation tank out; The first analysis unit comprises a first water quality detector, a second water quality detector, a first flow meter and a second flow meter; the first water quality detector and the first flow meter are arranged on the inlet pipe and are used to detect the water quality and flow of the sewage guided into the sewage treatment partition through the inlet pipe; The second water quality detector and the second flow meter are arranged on the outlet pipe and are used to detect the water quality and flow of the water treated by the sewage treatment partition and guided out through the outlet pipe.

6. A sewage treatment control method realized by using the sewage treatment system according to any one of claims 1 to 5, characterized by, comprises: receiving the first detection signal output by the first analysis unit, which represents the water quality parameters of the water guided into and out of the sewage treatment partition; receiving the second detection signal output by the second analysis unit, which represents the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the aerobic zone; controlling the amount of air guided into the aerobic zone by the aeration unit according to the parameters of ammonia nitrogen, nitrate nitrogen and dissolved oxygen in the aerobic zone and the water quality parameters of the water guided into the sewage treatment partition; controlling the amount of external carbon source guided into the anoxic zone by the external carbon source adding unit and the nitrification liquid reflux ratio of the nitrification liquid guided from the aerobic zone into the anoxic zone by the nitrification liquid reflux unit according to the parameters of ammonia nitrogen and nitrate nitrogen in the aerobic zone and the water quality parameters of the water guided out of the sewage treatment partition.

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