Low-carbon sewage treatment method

Abstract

The invention discloses a low-carbon sewage treatment method, and relates to the technical field of sewage treatment. The invention discloses a low-carbon sewage treatment method. The method comprises the following steps: S1, sewage enters an anaerobic zone through a pipeline I to degrade macromolecular pollutants and release phosphorus; s2, enabling effluent of the anaerobic zone to enter a first nitrification zone through a pipeline II to oxidize ammonia nitrogen; s3, effluent of the first nitrification area enters a second nitrification area through a first water passing hole to completely oxidize ammonia nitrogen; the baffle is arranged in the second nitration area, so that a more obvious ammonia nitrogen gradient can be formed, and the nitration effect of ammonia nitrogen is more thorough; water quality parameters are monitored in real time by utilizing equipment such as an ammonia nitrogen online monitor and a dissolved oxygen online monitor, and automatic regulation and control are realized through automatic control logic of a fan and a carbon source dosing pump, so that misjudgment caused by traditional subjective experience is avoided; and fault judgment logic is introduced, and a fault position is automatically positioned through multi-parameter linkage analysis, so that the maintainability and the stability of the system are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of sewage treatment, and in particular relates to a low-carbon sewage treatment method. Background Art

[0002] At present, the traditional sewage treatment method is mainly anaerobic-anoxic-aerobic (AAO). The incomplete oxidation of ammonia nitrogen at the front end causes low utilization rate of nitrate nitrogen at the back end, and the denitrification performance will also be low, thus affecting the overall sewage treatment effect.

[0003] The present invention provides a treatment process of anaerobic-aerobic zone (second nitrification zone)-anoxic. The baffle plate is set in the second nitrification zone to form a more obvious ammonia nitrogen gradient, ensuring that the nitrification of ammonia nitrogen is more thorough, which is beneficial for the denitrification and denitrification at the back end to have more reaction substrates, ensuring the overall sewage denitrification effect. Through the linkage control of online instruments, the misjudgment caused by traditional experience judgment can be avoided, so that production can be based on evidence, and the production situation can be predicted, thereby avoiding some emergencies. For this reason, a low-carbon sewage treatment method is proposed. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a low-carbon sewage treatment method that can overcome the above problems or at least partially solve the above problems.

[0005] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is: a low-carbon sewage treatment method, comprising the following steps: S1, sewage enters the anaerobic zone through pipe 1 for degradation of macromolecular pollutants and release of phosphorus; S2, the effluent from the anaerobic zone enters the first nitrification zone through pipeline 2 for oxidation of ammonia nitrogen; S3, the effluent from the first nitrification zone enters the second nitrification zone through the water hole 1 to completely oxidize the ammonia nitrogen; S4, the effluent from the second nitrification zone enters the anoxic zone through the second water hole for denitrification and nitrogen removal; S5, the effluent from the anoxic zone enters the secondary sedimentation tank through pipe three; S6. The sludge from the secondary sedimentation tank is returned to the anaerobic zone through pipeline four.

[0006] Preferably, a baffle is provided in the second nitrification zone, and the baffle divides the second nitrification zone into zones A, B, C, and D, and the volumes of zones B, C, and D are all 0.8 to 1.2 times the volume of zone A.

[0007] Preferably, the baffle is made of a modified polymer material containing digestive enzymes.

[0008] Preferably, the second water passing holes are arranged on the wall of area D in the second nitrification zone. After the sewage passes through areas A, B, C, and D in sequence, it flows to the anoxic zone through the second water passing holes.

[0009] Preferably, a stirrer is arranged in the anoxic zone, and the total power of the stirrer is 2 - 5 W per ton of water.

[0010] Furthermore, an ammonia nitrogen on-line monitor and a dissolved oxygen on-line monitor are arranged in area D of the second nitrification zone. The data of the ammonia nitrogen on-line monitor and the dissolved oxygen on-line monitor are used to control a blower, and the blower is used to aerate the second nitrification zone. The specific control steps are as follows: S7. Obtain the measured ammonia nitrogen value as A1 and the measured dissolved oxygen value as B1; Set adjustable set values as follows: A2: lower limit value of ammonia nitrogen, mg / L; A3: upper limit value of ammonia nitrogen, mg / L; A4: low ammonia nitrogen alarm value, mg / L; A5: high ammonia nitrogen alarm value, mg / L; B2: upper limit value of dissolved oxygen, mg / L; B3: lower limit value of dissolved oxygen, mg / L; B4: low dissolved oxygen alarm value, mg / L; B5: high dissolved oxygen alarm value, mg / L; H1: reduction amount of blower frequency, Hz; H2: increase amount of blower frequency, Hz; T1: running time, min; S8. Set the automatic control logic of the blower: ① When A1 ≤ A2, the running frequency of the blower is reduced by H1 from the original frequency; ② When A1 ≤ A4, the running frequency of the blower is reduced by 2 times H1 from the original frequency; ③ When A1 ≥ A3, the running frequency of the blower is increased by H2 from the original frequency; ④ When A1 ≥ A5, the running frequency of the blower is increased by 2 times H2 from the original frequency; ⑤ When A4 < A1 < A2, the control steps are as follows: When B3 < B1 < B2, the running frequency of the blower remains unchanged; When B1 ≤ B3, the running frequency of the blower is increased by H2 from the original frequency; When B1 ≥ B2, the running frequency of the blower is reduced by H2 from the original frequency; ⑥ After an interval of T1, repeat the above steps ① - ⑤.

[0011] Furthermore, a nitrate nitrogen on-line monitor and a carbon source dosing pump are arranged in the anoxic zone. The carbon source dosing pump is controlled according to the data of the nitrate nitrogen on-line monitor. The specific control steps are as follows: S9. Obtain the measured nitrate nitrogen value as C1 and the actual on-line flow rate Q1 of the carbon source dosing pump; Set adjustable set values as follows: C2: Nitrate nitrogen set value, mg / L; C3: High nitrate nitrogen alarm value, mg / L; G1: Equivalent COD value of the carbon source, mg / L; K1: Carbon source dosing ratio; N1: Nitrification liquid reflux ratio, %; H3: Reduction amount of the carbon source dosing pump frequency, Hz; H4: Increase amount of the carbon source dosing pump frequency, Hz; Q2: Theoretical calculated dosing amount of the carbon source, L / h; T2: Operating time, min; S10. Set the automatic control logic of the carbon source dosing pump as follows: ① When C1 ≤ C2, the carbon source dosing pump stops running; ② When C1 > C2, the carbon source dosing pump starts, and the specific control steps are as follows: Calculate Q2 = (C1 - C2) * N1 * K1 * Q1 * 1000 / G1; When Q1 < Q2, the operating frequency of the carbon source dosing pump increases by H4 from the original frequency; When Q1 = Q2, the operating frequency of the carbon source dosing pump remains unchanged; When Q1 ≥ Q2, the operating frequency of the carbon source dosing pump decreases by H3 from the original frequency; ③ After an interval of T2, repeat the above steps ①~②.

[0012] Furthermore, there are a and b values, which are the ammonia nitrogen and dissolved oxygen benchmarks during normal operation; Set the fault judgment logic, and the steps are as follows: S11. When A1 ≈ a and B1 ≈ b in areas A, B, C, and D, there is no fault in areas A, B, C, and D; S12. When A1 ≤ 0.2a or B1 ≤ 0.5b in area A or B or C or D, the ammonia nitrogen on-line monitor, dissolved oxygen on-line monitor, baffle or fan in this area is faulty; S13. When A1 ≥ 2a or B1 ≥ 2b in area A or B or C or D, the ammonia nitrogen on-line monitor, dissolved oxygen on-line monitor, baffle or fan in this area is faulty; S14. When A1 ≈ a and B1 ≤ 0.5b in area A or B or C or D, the dissolved oxygen on-line monitor or fan in this area is faulty. The fan fault can be verified by checking whether the dissolved oxygen value in the adjacent area is normal and whether the fan current and power meet the standards; S15. When A1≈a and B1≥2b in area A, B, C or D, the on-line dissolved oxygen monitor in this area fails or the fan logic control fails. The fan failure can be checked by whether the fan runs continuously at high frequency; S16. When A1≤0.2a and B1≈b in area A, B, C or D, the on-line ammonia nitrogen monitor in this area fails; S17. When A1≥2a and B1≈b in area A, B, C or D, the on-line ammonia nitrogen monitor in this area fails or the baffle fails; S18. When A1≤0.2a and B1≥2b in area A, B, C or D, the on-line ammonia nitrogen monitor, the on-line dissolved oxygen monitor or the fan in this area fails. If B1≥2b after replacing the sensors of the on-line dissolved oxygen monitor and the on-line ammonia nitrogen monitor, it is determined that the fan fails; S19. When A1≥2a and B1≤0.5b in area A, B, C or D, the baffle, the on-line ammonia nitrogen monitor, the on-line dissolved oxygen monitor or the fan in this area fails.

[0013] Further, when making fault judgments in S13, S17 and S19 above, an abnormal influent load judgment formula is added; (1). Let be the ammonia nitrogen load volatility

[0014] where is the influent ammonia nitrogen concentration at the current moment (mg / L), is the daily average value of the influent ammonia nitrogen concentration in the past 7 days (mg / L); If , it is determined that the influent ammonia nitrogen load is abnormal, and the threshold value of ammonia nitrogen a is adjusted according to the process load. If exceeds the standard and A1 increases synchronously, it is preferentially determined as an influent shock. An influent shock refers to a typical abnormal condition in the operation of a sewage treatment system, which means that the influent water quality or quantity fluctuates violently in a short time, resulting in a serious imbalance between the system treatment capacity and the actual load; (2). Let be the dissolved oxygen demand load volatility

[0015] where is the current influent flow rate (m³ / h), is the current ammonia nitrogen load (kg / h), is the daily average value of the ammonia nitrogen load in the past 7 days (kg / h); If , it is determined that there is an influent ammonia nitrogen load shock; Adjust the threshold of dissolved oxygen b according to the process load. If exceeds the standard and B1 decreases significantly, it is preferentially determined that the blower oxygen supply is insufficient.

[0016] Furthermore, when performing fault judgment in the above S13, S17, and S19, add a historical data trend comparison formula; (1) Let be the deviation degree of ammonia nitrogen / dissolved oxygen trend

[0017] where is the value of ammonia nitrogen (A1) or dissolved oxygen (B1) at the current moment or in the past n cycles, and the cycle is set to 1 hour. is the average value of the historical same period, and the historical same period is set to the same time period in the past 30 days. is the standard deviation of the historical same period; If , that is, the current value deviates from the historical average value by 2 times the standard deviation, it is determined as abnormal fluctuation; If exceeds the standard and there is no abnormal inlet load, it is preferentially determined that the ammonia nitrogen on-line monitor or the blower is faulty.

[0018] (2) Let be the gradient consistency test

[0019] where is the ammonia nitrogen value of the current partition, is the ammonia nitrogen value of the upstream partition, , are the average values of the historical same period; If , that is, the current gradient deviates from the historical gradient by more than 10%, it is determined that the baffle is faulty or the mixing is abnormal. If exceeds the standard and the inlet load is normal, it is preferentially determined that the baffle is short-circuited.

[0020] Furthermore, the baffle is composed of a first baffle layer and a second baffle layer. The first baffle layer is arranged to be lifted and lowered. Ultrasonic generators and air spray pipes are respectively installed in the A, B, C, and D areas. A number of air spray holes are opened on the air spray pipe. When the air spray pipe is immersed in water, the air spray holes are inclined upward towards the baffle, so that the gas pushes the water flow to wash the first baffle layer.

[0021] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: By setting baffles in the second nitrification zone, a more obvious ammonia nitrogen gradient can be formed in the present invention, ensuring more complete nitrification of ammonia nitrogen; Using equipment such as an ammonia nitrogen on-line monitor and a dissolved oxygen on-line monitor to monitor water quality parameters in real time, and through the automatic control logic of the blower and the carbon source dosing pump, automatic regulation is achieved, avoiding misjudgment caused by traditional subjective experience; Introducing a fault judgment logic, through multi-parameter linkage analysis, the fault location is automatically located, improving the maintainability and stability of the system; Through historical data trend comparison and abnormal influent load judgment, the anti-interference ability and fault diagnosis accuracy of the system are further improved; This low-carbon sewage treatment method significantly improves the sewage treatment efficiency and quality, reduces energy consumption and operating costs, while enhancing the adaptability and maintainability of the system through technological innovation and intelligent control, with significant economic and social benefits; Among them, the fault judgment for the baffle can further improve the sustainable performance of the baffle in the second nitrification zone, and then effectively maintain the ammonia nitrogen gradient effect formed in the second nitrification zone for a long time, improving the efficiency and performance of sewage treatment.

[0022] 1. This low-carbon sewage treatment method: There are baffles arranged in the second nitrification zone, and the baffles divide the second nitrification zone into areas A, B, C, and D. The volumes of areas B, C, and D are all 0.8 - 1.2 times the volume of area A; Area A is used as the core high-load nitrification zone, preferentially receiving the high-concentration ammonia nitrogen in the effluent from the first nitrification zone; Areas B, C, and D are used as deep nitrification buffer zones. The similar volume design can disperse the peak value of ammonia nitrogen load and avoid microbial metabolism overload in a single area. The setting of the volumes of areas B, C, and D enables area A to bear the instantaneous high load when the influent ammonia nitrogen concentration fluctuates, and areas B, C, and D maintain the system stability through redundant volumes, reducing the fluctuation of the total nitrogen removal rate.

[0023] 2. This low-carbon sewage treatment method: By adjusting the frequency of the carbon source dosing pump in real time according to the nitrate nitrogen value, it can ensure that the denitrifying bacteria are always in a highly efficient metabolic state, while avoiding waste caused by excessive addition of carbon source, effectively saving the operating cost. At the same time, the increase and decrease of the frequency of the carbon source dosing pump can also stabilize the effluent water quality, avoid the risk of exceeding the standard, and optimize the microbial community, improving the stability of the sewage treatment system. By monitoring the nitrate nitrogen value through a nitrate nitrogen on-line monitor, it can effectively reduce the manual intervention and operation and maintenance costs, and automatically replace the manual detection of the nitrate nitrogen value. Therefore, real-time regulation of the carbon source dosing pump is the core technical means for sewage treatment plants to achieve "quality improvement and efficiency increase". Through the three-dimensional optimization of process - cost - safety, it can bring significant economic and environmental benefits to enterprises.

[0024] 3. The low-carbon sewage treatment method: During the sewage treatment process, a fault judgment logic is added. Through refined zoning monitoring and multi-parameter linkage analysis, the accuracy, timeliness, and maintainability of system fault diagnosis are significantly improved, filling the fault diagnosis blind spot of traditional methods in a low DO environment, and effectively improving the positioning accuracy rate.

[0025] 4. The low-carbon sewage treatment method: In logical judgments such as S13 (A1≥2a, B1≥2b), S17 (A1≥2a, B1≈b), and S19 (A1≥2a, B1≤0.5b), first, the influence of influent shock is excluded by judging the abnormal influent load and comparing with the historical data trend, shortening the fault positioning time and reducing unnecessary shutdowns.

[0026] 5. The low-carbon sewage treatment method: When it is judged as a baffle fault, the ultrasonic generator and the air injection pipe can be moved closer to the baffle. The ultrasonic generator is used to make the water fluctuate, and the water fluctuation is used to clean the surface of the baffle, eliminating the baffle fault caused by blockage problems. The air injection pipe is moved closer to the baffle and immersed in the water, and air is ejected through the air injection pipe to further clean the surface of the first layer of the baffle.

[0027] 6. The low-carbon sewage treatment method: Additional winch devices are installed in areas A, B, C, and D respectively. The first layer of the baffle in areas A, B, C, and D is controlled to rise and fall by the set winch devices. When it is judged as a baffle fault, the first layer of the baffle is pulled up by the winch device, and the ultrasonic generator and the air injection pipe are combined to clean the surface of the raised first layer of the baffle. Since the water flow in the second nitrification zone flows from area A to area D, the dirt in areas A, B, C, and D is more concentrated on the first layer of the baffle, and there is less dirt on the second layer of the baffle. Therefore, by raising the first layer of the baffle and cleaning it during the raising process, the second layer of the baffle can still play a role. This enables the baffle to first clean and eliminate the blockage cause when a fault occurs, or clean the first layer of the baffle while using the second layer of the baffle. When the ultrasonic generator and the air injection pipe clean the first layer of the baffle during the raising process, since the first layer of the baffle will gradually leave the water surface and will not be re-polluted, the cleaning effect can be maintained.

[0028] The following further describes in detail the specific implementation manners of the present invention with reference to the accompanying drawings. Description of the Drawings

[0029] In the drawings: Figure 1 is a schematic flow chart of a low-carbon sewage treatment method proposed by the present invention; Figure 2 is a schematic structural diagram of an air injection pipe and air injection holes of a low-carbon sewage treatment method proposed by the present invention; Figure 3Schematic diagram of the structure of the water penetration holes of a low-carbon sewage treatment method proposed by the present invention.

[0030] In the figure: 10, ultrasonic generator; 20, air injection pipe; 201, air injection hole; 3, baffle; 301, first layer of the baffle; 302, second layer of the baffle; 303, water penetration hole; 11, anaerobic zone; 110, pipe one; 12, first nitrification zone; 121, pipe two; 122, water passing hole one; 13, second nitrification zone; 131, water passing hole two; 14, anoxic zone; 141, pipe three; 15, secondary sedimentation tank; 151, pipe four; 16, impeller. Specific embodiments

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0032] The following combines the attached Figure 1 - attached Figure 3 , and details the technical solutions provided by each embodiment of the present invention.

[0033] Embodiment 1: Refer to Figure 1 - Figure 2 , a low-carbon sewage treatment method, including the following steps: S1. Sewage enters the anaerobic zone 11 through the pipe one 110 for the degradation of macromolecular pollutants and phosphorus release; S2. The effluent from the anaerobic zone 11 enters the first nitrification zone 12 through the pipe two 121 for the oxidation of ammonia nitrogen; S3. The effluent from the first nitrification zone 12 enters the second nitrification zone 13 through the water passing hole one 122 to completely oxidize ammonia nitrogen; S4. The effluent from the second nitrification zone 13 enters the anoxic zone 14 through the water passing hole two 131 for denitrification and nitrogen removal; S5. The effluent from the anoxic zone 14 enters the secondary sedimentation tank 15 through the pipe three 141; S6. The sludge in the secondary sedimentation tank 15 is refluxed to the anaerobic zone 11 through the pipe four 151.

[0034] In the above treatment method, the phosphorus release in the anaerobic zone 11 is coupled with the denitrification and phosphorus removal in the anoxic zone 14 to achieve "dual use of one carbon", breaking through the contradiction of carbon source distribution in traditional processes. The first and second nitrification zones 13 ensure the complete oxidation of ammonia nitrogen and avoid the inhibition of denitrifying bacteria caused by the accumulation of nitrite. This process is applicable to the upgrading of urban sewage treatment plants, the comprehensive treatment of industrial park wastewater, and the decentralized sewage treatment scenarios in rural areas.

[0035] A baffle 3 is provided in the second nitrification zone 13. The baffle 3 divides the second nitrification zone 13 into zones A, B, C, and D. The volumes of zones B, C, and D are all 0.8 - 1.2 times the volume of zone A. Zone A serves as the core high-load nitrification zone and preferentially receives the high-concentration ammonia nitrogen in the effluent from the first nitrification zone 12. Zones B, C, and D serve as deep nitrification buffer zones. The similar designed volumes can disperse the peak ammonia nitrogen load and avoid the overloading of microbial metabolism in a single zone. The setting of the volumes of zones B, C, and D enables zone A to bear the instantaneous high load when the influent ammonia nitrogen concentration fluctuates. Zones B, C, and D maintain the system stability through redundant volumes and reduce the fluctuation of the total nitrogen removal rate.

[0036] Meanwhile, a more obvious ammonia nitrogen gradient can be formed to ensure more complete nitrification of ammonia nitrogen, which is beneficial for the denitrification at the back end to have more reaction substrates and ensures the overall sewage denitrification effect. Among them, zones A, B, C, and D all support independent aeration control.

[0037] The material is a modified polymer material, which contains digestive enzymes. The modified polymer material containing digestive enzymes is introduced into the baffle 3 in the second nitrification zone 13 to eliminate the competition of organic nitrogen, reduce the consumption of DO by heterotrophic bacteria, quickly decompose toxic substances such as hydroxylamine, protect the activity of NOB, and significantly improve the nitrification efficiency, reduce energy consumption and enhance the system stability through the synergistic effect of enzymatic pretreatment - microbial metabolism.

[0038] The water passing hole two 131 is arranged on the wall of zone D of the second nitrification zone 13. After the sewage passes through zones A, B, C, and D in sequence, it flows to the anoxic zone 14 through the water passing hole two 131. The water passing hole two 131 is horizontally opened.

[0039] A stirrer 16 is provided in the anoxic zone 14. The total power of the stirrer 16 is 2 - 5 W per ton of water. Since the anoxic zone 14 often has uneven flow patterns, resulting in residual DO or uneven distribution of carbon sources, the setting of the stirrer 16 can increase the flow velocity through forced convection, reduce the proportion of the dead zone volume, and ensure sufficient contact between denitrifying bacteria and carbon sources.

[0040] Example 2: A low-carbon sewage treatment method is basically the same as Example 1. Further, an ammonia nitrogen on-line monitor and a dissolved oxygen on-line monitor are provided in zone D of the second nitrification zone 13. The data of the ammonia nitrogen on-line monitor and the dissolved oxygen on-line monitor are used to regulate the blower. The blower is used to aerate the second nitrification zone 13. The specific regulation steps are as follows: S7. Obtain the measured ammonia nitrogen value as A1 and obtain the measured dissolved oxygen value as B1. Set adjustable set values, specifically as follows: A2: Lower limit value of ammonia nitrogen, mg / L; A3: Upper limit value of ammonia nitrogen, mg / L; A4: Low ammonia nitrogen alarm value, mg / L; A5: High ammonia nitrogen alarm value, mg / L; B2: Upper limit value of dissolved oxygen, mg / L; B3: Lower limit value of dissolved oxygen, mg / L; B4: Low dissolved oxygen alarm value, mg / L; B5: High dissolved oxygen alarm value, mg / L; H1: Reduction amount of fan frequency, Hz, reducing aeration volume; H2: Increase amount of fan frequency, Hz, increasing aeration volume; T1: Operating time, min; S8. Set the automatic control logic of the fan: ① When A1 ≤ A2, the operating frequency of the fan is reduced by H1 from the original frequency; ② When A1 ≤ A4, the operating frequency of the fan is reduced by 2 times H1 from the original frequency; ③ When A1 ≥ A3, the operating frequency of the fan is increased by H2 from the original frequency; ④ When A1 ≥ A5, the operating frequency of the fan is increased by 2 times H2 from the original frequency; ⑤ When A4 < A1 < A2, the control steps are as follows: When B3 < B1 < B2, the operating frequency of the fan remains unchanged; When B1 ≤ B3, the operating frequency of the fan is increased by H2 from the original frequency; When B1 ≥ B2, the operating frequency of the fan is reduced by H2 from the original frequency; ⑥ After an interval of T1, repeat the above steps ① - ⑤.

[0041] An online nitrate nitrogen monitor and a carbon source dosing pump are installed in the anoxic zone 14. The carbon source dosing pump is regulated according to the data of the online nitrate nitrogen monitor. The specific regulation steps are as follows: S9. Obtain the measured nitrate nitrogen value as C1 and the actual online flow rate Q1 of the carbon source dosing pump; Set adjustable set values as follows: C2: Nitrate nitrogen set value, mg / L; C3: High nitrate nitrogen alarm value, mg / L; G1: Equivalent COD value of the carbon source, mg / L; K1: Carbon source dosing ratio; N1: Nitrification liquid reflux ratio, %; H3: Reduction amount of carbon source dosing pump frequency, Hz; H4: Increase amount of carbon source dosing pump frequency, Hz; Q2: Theoretical calculated dosing amount of the carbon source, L / h; T2: Operating time, min; S10. Set the automatic control logic of the carbon source dosing pump as follows: ① When C1 ≤ C2, the carbon source dosing pump stops running; ② When C1 > C2, the carbon source dosing pump starts, and the specific control steps are as follows: Calculate Q2 = (C1 - C2) * N1 * K1 * Q1 * 1000 / G1; When Q1 < Q2, the operating frequency of the carbon source dosing pump increases by H4 from the original frequency; When Q1 = Q2, the operating frequency of the carbon source dosing pump remains unchanged; When Q1 ≥ Q2, the operating frequency of the carbon source dosing pump decreases by H3 from the original frequency; ③ After an interval of T2, repeat the above steps ①~②; By adjusting the frequency of the carbon source dosing pump in real time according to the nitrate nitrogen value, it can ensure that the denitrifying bacteria are always in a highly efficient metabolic state, while avoiding waste caused by excessive addition of carbon source, effectively saving the operating cost. At the same time, the increase and decrease of the frequency of the carbon source dosing pump can also stabilize the effluent quality, avoid the risk of exceeding the standard, and optimize the microbial community, improving the stability of the sewage treatment system. By monitoring the nitrate nitrogen value through a nitrate nitrogen on-line monitor, it can effectively reduce the manual intervention and operation and maintenance costs, and the automatic detection of the nitrate nitrogen value replaces manual detection. Therefore, the real-time regulation of the carbon source dosing pump is the core technical means for the sewage treatment plant to achieve "quality improvement and efficiency increase". Through the three-dimensional optimization of process - cost - safety, it can bring significant economic and environmental benefits to the enterprise.

[0042] Example 3: A low-carbon sewage treatment method is basically the same as Example 2. Further, there are a and b values, which are the ammonia nitrogen and dissolved oxygen benchmarks during normal operation; Set the fault judgment logic, and the steps are as follows: S11. When A1 ≈ a and B1 ≈ b in areas A, B, C, and D, there is no fault in areas A, B, C, and D; S12. When A1 ≤ 0.2a or B1 ≤ 0.5b in area A or B or C or D, the ammonia nitrogen on-line monitor, dissolved oxygen on-line monitor, or fan in this area has a fault; S13. When A1 ≥ 2a or B1 ≥ 2b in area A or B or C or D, the ammonia nitrogen on-line monitor, dissolved oxygen on-line monitor, or fan in this area has a fault; S14. When A1 ≈ a and B1 ≤ 0.5b in area A or B or C or D, the dissolved oxygen on-line monitor or fan in this area has a fault. The fan fault can be verified by checking whether the dissolved oxygen value in the adjacent area is normal and whether the fan current and power meet the standards; S15. When A1 ≈ a and B1 ≥ 2b in area A or B or C or D, the dissolved oxygen on-line monitor or fan logic control in this area has a fault. The fan fault can be verified by checking whether the fan runs continuously at a high frequency; S16. When A1 ≤ 0.2a and B1 ≈ b in area A, B, C or D, the on-line ammonia nitrogen monitor in this area fails; the fault location can be automatically located.

[0043] S17. When A1 ≥ 2a and B1 ≈ b in area A, B, C or D, the on-line ammonia nitrogen monitor in this area has a fault or malfunctions. S18. When A1 ≤ 0.2a and B1 ≥ 2b in area A, B, C or D, the on-line ammonia nitrogen monitor, on-line dissolved oxygen monitor or the fan in this area fails. If B1 ≥ 2b after replacing the sensors of the on-line dissolved oxygen monitor and the on-line ammonia nitrogen monitor, it is determined that the fan has a fault. S19. When A1 ≥ 2a and B1 ≤ 0.5b in area A, B, C or D, the baffle 3, on-line ammonia nitrogen monitor, on-line dissolved oxygen monitor or the fan in this area fails.

[0044] During the sewage treatment process, by adding a fault judgment logic and through refined partition monitoring and multi-parameter linkage analysis, the accuracy, timeliness and maintainability of system fault diagnosis are significantly improved, filling the blind spot of fault diagnosis in the traditional method under low DO environment, and effectively improving the positioning accuracy rate.

[0045] Example 4: A low-carbon sewage treatment method is basically the same as that in Example 3. Further, before the fault judgment in S13, S17 and S19 above, an abnormal influent load judgment method is added to first exclude whether there is an abnormal influent load in the steps of S13, S17 and S19, thereby improving the accuracy of the judgment in S13, S17 and S19; where the abnormal influent load is the influent shock, and the influent shock is a typical abnormal working condition in the operation of the sewage treatment system, referring to the sudden fluctuation of the influent water quality or quantity within a short time, resulting in a serious imbalance between the system treatment capacity and the actual load. Abnormal influent load judgment formula; (1). Let be the ammonia nitrogen load volatility

[0046] where, is the influent ammonia nitrogen concentration at the current moment (mg / L), is the daily average value of the influent ammonia nitrogen concentration in the past 7 days (mg / L); If , it is determined that the influent ammonia nitrogen load is abnormal, and the threshold value of ammonia nitrogen a is adjusted according to the process load. If exceeds the standard and A1 increases synchronously, it is preferentially determined as an influent shock; By comparing the current influent ammonia nitrogen concentration with the daily average value in the past 7 days, if the volatility exceeds the set threshold, it is determined that the influent ammonia nitrogen load is abnormal, and the reference value a is dynamically adjusted to avoid misjudging the falsely high ammonia nitrogen value A1 caused by influent shock as a sensor or a fault.

[0047] (2). Let be the volatility of the dissolved oxygen demand load

[0048] where is the current influent flow rate (m³ / h), is the current ammonia nitrogen load (kg / h), is the daily average value of the ammonia nitrogen load in the past 7 days (kg / h); If , it is determined that there is an influent ammonia nitrogen load shock; Adjust the threshold of the dissolved oxygen b according to the process load. If exceeds the standard and B1 decreases significantly, it is preferentially determined that the blower oxygen supply is insufficient.

[0049] Combined with the influent flow rate Q and compared with the daily average value in the past 7 days, if the volatility exceeds the threshold, it is determined that there is an influent ammonia nitrogen load shock, and the reference value b is dynamically adjusted to avoid misjudging the falsely low dissolved oxygen value B1 caused by load mutation as a blower fault.

[0050] Example 5: A low-carbon sewage treatment method is basically the same as that in Example 4. Further, when performing fault judgment in the above S13, S17, and S19, a historical data trend comparison formula is added; (1). Let be the deviation degree of ammonia nitrogen / dissolved oxygen trend

[0051] where is the ammonia nitrogen (A1) or dissolved oxygen (B1) value at the current moment or in the past n cycles, and the cycle is set to 1 hour, is the mean value of the same historical period, and the same historical period is set to the same time period in the past 30 days, is the standard deviation of the same historical period; If , that is, the current value deviates from the historical mean by 2 standard deviations, it is determined that there is an abnormal fluctuation; If exceeds the standard and there is no abnormal influent load, it is preferentially determined that the ammonia nitrogen on-line monitor or the blower is faulty; By comparing the current value with the mean value and standard deviation of the same time period in the past 30 days, if the deviation degree exceeds 2 standard deviations, it is determined that there is an abnormal fluctuation. This method can effectively filter out short-term fluctuations caused by environmental factors such as influent temperature and pH, and avoid misjudgment.

[0052] (2) Set as the gradient consistency test

[0053] wherein, is the ammonia nitrogen value of the current partition, is the ammonia nitrogen value of the upstream partition, and is the historical average value for the same period; If , that is, if the current gradient deviates from the historical gradient by more than 10%, it is determined as a fault or mixing anomaly. If exceeds the standard and the influent load is normal, it is preferentially determined as a short circuit; By comparing the ammonia nitrogen values of the current partition and the upstream partition and the historical gradient average value, if the gradient deviation exceeds 10%, it is determined as a short circuit or mixing anomaly. This method can distinguish local faults from global load fluctuations and avoid missed fault judgments.

[0054] Therefore, by introducing the judgment of influent load anomaly and the comparative analysis of historical data trends, the accuracy of fault judgment can be further improved, and the anti-interference ability, fault diagnosis accuracy and process stability of the low-carbon sewage treatment system under complex working conditions can be significantly enhanced.

[0055] In summary, in logical judgments such as S13 (A1≥2a, B1≥2b), S17 (A1≥2a, B1≈b), S19 (A1≥2a, B1≤0.5b), etc., it is preferred to exclude influent shock interference through the judgment of influent load anomaly and the comparison of historical data trends, shorten the fault location time, and reduce unnecessary shutdowns.

[0056] Example 6: Refer to Figure 1 and Figure 2 , a low-carbon sewage treatment method, which is basically the same as Example 5, and further: it is composed of a first baffle layer 301 and a second baffle layer 302. The first baffle layer 301 is arranged to be lifted. Ultrasonic generators 10 and air injection pipes 20 are respectively installed in areas A, B, C, and D. A number of air injection holes 201 are equally spaced on the air injection pipe 20.

[0057] Independent X and Y-axis lead screws are respectively installed in areas A, B, C, and D. A nut is threadedly connected to the X and Y-axis lead screws. It should be understood that protective sleeves are sleeved on the X and Y-axis lead screws to prevent the lead screws from being corroded.

[0058] A winch is installed on the nut. The ultrasonic generator 10 and the air injection pipe 20 are installed on the connecting frame of the lifting rope of the winch; Drive the ultrasonic generator 10 and the air jet pipe 20 to move in areas A, B, C or D through the X and Y axis lead screws; and control the lifting of the ultrasonic generator 10 and the air jet pipe 20 through a winch; When a failure is judged, the ultrasonic generator 10 and the air jet pipe 20 can be brought closer, the ultrasonic generator 10 is used to make the water fluctuate, the surface is cleaned by the fluctuation of the water, the failure caused by the blockage problem is eliminated, and the air jet pipe 20 is brought closer and immersed in the water, and air is blown out through the air jet pipe 20 to further clean the surface of the first layer 301 of the baffle.

[0059] Furthermore, additional winch devices are respectively installed in areas A, B, C, and D. The first layer 301 of the baffle in areas A, B, C, and D is controlled to lift by the provided winch devices. When a failure is judged, the first layer 301 of the baffle is pulled up by the winch devices, and the surface of the lifted first layer 301 of the baffle is cleaned in combination with the ultrasonic generator 10 and the air jet pipe 20 (it should be understood that the lifting speed is adjustable). Since the water flow in the second nitrification area 13 is from area A to area D, the dirt in areas A, B, C, and D is more concentrated on the first layer 301 of the baffle, and there is less dirt on the second layer 302 of the baffle. Therefore, by lifting the first layer 301 of the baffle and cleaning it during the lifting process, while the second layer 302 of the baffle can still play a role, this enables the blockage cause to be eliminated by cleaning first when a failure occurs, or the first layer 301 of the baffle can be cleaned while using the second layer 302 of the baffle.

[0060] During the lifting process of the first layer 301 of the baffle, when the ultrasonic generator 10 and the air jet pipe 20 clean it, since the first layer 301 of the baffle will gradually leave the water surface and will not be re - polluted, the cleaning effect can be maintained.

[0061] When necessary, the first layer 301 and the second layer 302 of the baffle can be replaced.

[0062] In some embodiments, referring to Figure 3 , the first layer 301 and the second layer 302 of the baffle are sleeved. Specifically, a concave chute is opened in the first layer 301 of the baffle. The upper end of the concave chute is through - shaped, and the second layer 302 of the baffle is slidably connected in the concave chute of the first layer 301 of the baffle. Water - passing holes 303 are opened on both the first layer 301 and the second layer 302 of the baffle; During normal use, water overflows from the second layer 302 of the baffle. The second layer 302 of the baffle can be lifted and lowered through the provided winch. When the second layer 302 of the baffle is lifted, the water - passing holes 303 coincide and communicate, so that the water in the second nitrification area 13 can continue to flow without affecting the use.

[0063] Among them, in this embodiment, microorganisms such as moss and lichen are attached to the first baffle layer 301 and the second baffle layer 302.

[0064] Therefore, when the baffle 3 fails, the first baffle layer 301 can be raised for repair, maintenance or replacement, thereby ensuring the continuity of the ammonia nitrogen gradient effect formed in the second nitrification zone 13, and further improving the sewage treatment effect.

[0065] The present invention can form a more obvious ammonia nitrogen gradient in the second nitrification zone 13 to ensure more complete nitrification of ammonia nitrogen; uses devices such as an ammonia nitrogen online monitor and a dissolved oxygen online monitor to monitor water quality parameters in real time, and realizes automatic regulation through the automatic control logic of a fan and a carbon source dosing pump, avoiding misjudgment caused by traditional subjective experience; introduces a fault judgment logic, automatically locates the fault position through multi-parameter linkage analysis, and improves the maintainability and stability of the system; further improves the anti-interference ability and fault diagnosis accuracy of the system through historical data trend comparison and abnormal inlet load judgment; this low-carbon sewage treatment method significantly improves the sewage treatment efficiency and quality, reduces energy consumption and operating costs, while enhancing the adaptability and maintainability of the system, and has significant economic and social benefits through technological innovation and intelligent control.

[0066] The above description is only a preferred embodiment of the present invention, and does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments by using the technical content prompted above within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the present invention.

Claims

1. A low-carbon sewage treatment method, characterized in that, It includes the following steps: S1. Sewage enters the anaerobic zone (11) through pipeline 1 (110) for the degradation of macromolecular pollutants and phosphorus release; S2. The effluent from the anaerobic zone (11) enters the first nitrification zone (12) through pipeline 2 (121) for ammonia nitrogen oxidation; S3. The effluent from the first nitrification zone (12) enters the second nitrification zone (13) through water passing hole 1 (122) to completely oxidize ammonia nitrogen; S4. The effluent from the second nitrification zone (13) enters the anoxic zone (14) through water passing hole 2 (131) for denitrification and nitrogen removal; S5. The effluent from the anoxic zone (14) enters the secondary sedimentation tank (15) through pipeline 3 (141); S6. The sludge in the secondary sedimentation tank (15) flows back to the anaerobic zone (11) through pipeline 4 (151).

2. The low-carbon sewage treatment method according to claim 1, wherein A baffle (3) is arranged in the second nitrification zone (13). The baffle (3) divides the second nitrification zone (13) into areas A, B, C, and D. The volumes of areas B, C, and D are all 0.8 - 1.2 times the volume of area A.

3. A low-carbon sewage treatment method according to claim 2, characterized in that, The material of the baffle (3) is a modified polymer material, which contains digestive enzymes.

4. A low-carbon sewage treatment method according to claim 2, characterized in that The water passing hole 2 (131) is arranged on the wall of area D of the second nitrification zone (13). After the sewage passes through areas A, B, C, and D in sequence, it flows to the anoxic zone (14) through the water passing hole 2 (131).

5. A low-carbon sewage treatment method according to claim 1, characterized in that, A stirrer (16) is arranged in the anoxic zone (14). The total power of the stirrer (16) is 2 - 5 W per ton of water.

6. A low-carbon sewage treatment method according to claim 2, characterized in that, An ammonia nitrogen on-line monitor and a dissolved oxygen on-line monitor are arranged in area D of the second nitrification zone (13). The data of the ammonia nitrogen on-line monitor and the dissolved oxygen on-line monitor are used to regulate a blower. The blower is used to aerate the second nitrification zone (13). The specific regulation steps are as follows: S7. Obtain the measured ammonia nitrogen value as A1 and the measured dissolved oxygen value as B1; Set adjustable set values, specifically as follows: A2: ammonia nitrogen lower limit value, mg / L; A3: ammonia nitrogen upper limit value, mg / L; A4: low ammonia nitrogen alarm value, mg / L; A5: high ammonia nitrogen alarm value, mg / L; B2: dissolved oxygen upper limit value, mg / L; B3: dissolved oxygen lower limit value, mg / L; B4: low dissolved oxygen alarm value, mg / L; B5: high dissolved oxygen alarm value, mg / L; H1: blower frequency reduction amount, Hz; H2: blower frequency increase amount, Hz; T1: running time, min; S8. Set the automatic control logic of the blower: ① When A1 ≤ A2, the running frequency of the blower is reduced by H1 from the original frequency; ② When A1 ≤ A4, the running frequency of the blower is reduced by 2 times H1 from the original frequency; ③ When A1 ≥ A3, the running frequency of the blower is increased by H2 from the original frequency; ④ When A1 ≥ A5, the running frequency of the blower is increased by 2 times H2 from the original frequency; ⑤ When A4 < A1 < A2, the control steps are as follows: When B3 < B1 < B2, the running frequency of the blower remains unchanged; When B1 ≤ B3, the running frequency of the blower is increased by H2 from the original frequency; When B1 ≥ B2, the running frequency of the blower is reduced by H2 from the original frequency; ⑥ After an interval of T1, repeat the above steps ① - ⑤.

7. A low-carbon sewage treatment method according to claim 1, characterized in that, A nitrate nitrogen online monitor and a carbon source dosing pump are installed in the anoxic zone (14), and the carbon source dosing pump is regulated according to the data of the nitrate nitrogen online monitor. The specific regulation steps are as follows: S9. Obtain the measured nitrate nitrogen value C1 and the actual online flow rate Q1 of the carbon source dosing pump; Set adjustable set values as follows: C2: nitrate nitrogen set value, mg / L; C3: high nitrate nitrogen alarm value, mg / L; G1: equivalent COD value of the carbon source, mg / L; K1: carbon source dosing ratio; N1: nitrification liquid reflux ratio, %; H3: reduction amount of the frequency of the carbon source dosing pump, Hz; H4: increase amount of the frequency of the carbon source dosing pump, Hz; Q2: theoretically calculated dosing amount of the carbon source, L / h; T2: running time, min; S10. Set the automatic control logic of the carbon source dosing pump as follows: ① When C1 ≤ C2, the carbon source dosing pump stops running; ② When C1 > C2, the carbon source dosing pump starts. The specific control steps are as follows: Calculate Q2 = (C1 - C2) * N1 * K1 * Q1 * 1000 / G1; When Q1 < Q2, the running frequency of the carbon source dosing pump increases by H4 from the original frequency; When Q1 = Q2, the running frequency of the carbon source dosing pump remains unchanged; When Q1 ≥ Q2, the running frequency of the carbon source dosing pump decreases by H3 from the original frequency; ③ After an interval of T2, repeat the above steps ①~②.

8. A low-carbon sewage treatment method according to claim 6, characterized in that, There are a and b values, which are the ammonia nitrogen and dissolved oxygen benchmarks during normal operation; Set the fault judgment logic. The steps are as follows: S11. When A1 ≈ a and B1 ≈ b in areas A, B, C, and D, there is no fault in areas A, B, C, and D; S12. When A1 ≤ 0.2a or B1 ≤ 0.5b in area A or B or C or D, the ammonia nitrogen online monitor, dissolved oxygen online monitor, baffle (3) or fan in this area is faulty; S13. When A1 ≥ 2a or B1 ≥ 2b in area A or B or C or D, the ammonia nitrogen online monitor, dissolved oxygen online monitor, baffle (3) or fan in this area is faulty; S14. When A1 ≈ a and B1 ≤ 0.5b in area A or B or C or D, the dissolved oxygen online monitor or fan in this area is faulty. The fan fault can be verified by checking whether the dissolved oxygen value in the adjacent area is normal and whether the fan current and power meet the standards; S15. When A1 ≈ a and B1 ≥ 2b in area A or B or C or D, the dissolved oxygen online monitor or fan logic control in this area is faulty. The fan fault can be verified by checking whether the fan runs continuously at a high frequency; S16. When A1 ≤ 0.2a and B1 ≈ b in area A or B or C or D, the ammonia nitrogen online monitor in this area is faulty; S17. When A1 ≥ 2a and B1 ≈ b in area A or B or C or D, the ammonia nitrogen online monitor or baffle (3) in this area is faulty; S18. When A1 ≤ 0.2a and B1 ≥ 2b in area A or B or C or D, the ammonia nitrogen online monitor, dissolved oxygen online monitor or fan in this area is faulty. If B1 ≥ 2b after replacing the sensors of the dissolved oxygen online monitor and the ammonia nitrogen online monitor, it is determined that the fan is faulty; S19. When A1 ≥ 2a, B1 ≤ 0.5b in area A, B, C or D, there is a fault with the baffle (3), ammonia nitrogen on-line monitor, dissolved oxygen on-line monitor or fan in this area.

9. A low-carbon sewage treatment method according to claim 8, characterized in that, When making a fault judgment in the above S13, S17, and S19, add a formula for judging abnormal influent load; (1), Let be the ammonia nitrogen load volatility ， Among them, is the influent ammonia nitrogen concentration at the current moment (mg / L), is the daily average value of the influent ammonia nitrogen concentration in the past 7 days (mg / L); If , it is determined that the influent ammonia nitrogen load is abnormal; (2). Set as the volatility of dissolved oxygen demand load ， Among them, is the current water inflow (m³ / h), is the current ammonia nitrogen load (kg / h), is the daily average value of the ammonia nitrogen load in the past 7 days (kg / h); If , it is determined as an impact on the influent ammonia nitrogen load.

10. A low-carbon sewage treatment method according to claim 9, characterized in that, When making a fault judgment in the above S13, S17, and S19, add a formula for comparing historical data trends; (1). Set as the deviation degree of ammonia nitrogen / dissolved oxygen trend ， Among them, is the value of ammonia nitrogen (A1) or dissolved oxygen (B1) at the current moment or in the past n cycles, is the mean value in the same historical period, is the standard deviation in the same historical period; If , that is, the current value deviates from the historical mean by 2 standard deviations, it is determined as an abnormal fluctuation; (2). Let be the gradient consistency test ， in, is the current partition ammonia nitrogen value, is the ammonia nitrogen value of the upstream partition, , It is the historical average for the same period; If , that is, if the current gradient deviates from the historical gradient by more than 10%, it is determined that there is a fault in the baffle (3) or a mixing anomaly.

11. A low-carbon sewage treatment method according to claim 9, characterized in that, The baffle (3) is composed of a first baffle layer (301) and a second baffle layer (302). The first baffle layer (301) is arranged to be lifted and lowered. Ultrasonic generators (10) and air injection pipes (20) are respectively installed in areas A, B, C, and D.

12. A low-carbon sewage treatment method according to claim 9, characterized in that, The baffle (3) is composed of a first baffle layer (301) and a second baffle layer (302). The second baffle layer (302) is slidably connected to the first baffle layer (301). Water passing holes (303) are formed in both the first baffle layer (301) and the second baffle layer (302). The second baffle layer (302) is arranged to be lifted and lowered.

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