Denitrification and phosphorus removal process and reactor

Abstract

The application relates to the technical field of sewage treatment, in particular to a denitrification and phosphorus removal process and a reactor, which comprises: a denitrification and phosphorus removal cycle repeated continuously and repeatedly, each denitrification and phosphorus removal cycle comprising: adding sewage containing NH4 + and PO4 3‑ into a reactor; continuously introducing oxygen into the sewage and continuously stirring the sewage; stopping the introduction of oxygen into the sewage and stopping the stirring of the sewage, adding a carbon source concentrate into the sewage; after continuously stirring the sewage for a preset time length, standing the sewage; discharging a preset amount of supernatant from the reactor; after continuously introducing oxygen into the sewage and continuously stirring the sewage, standing the sewage. The application aims to provide a denitrification and phosphorus removal process and a reactor in the prior art.

Description

Technical Field

[0001] This application relates to the field of wastewater treatment technology, and more specifically, to a nitrogen and phosphorus removal process and reactor. Background Technology

[0002] Traditional wastewater nitrogen and phosphorus removal combines biological phosphorus removal processes with biological nitrification-denitrification processes. Traditional biological phosphorus removal involves two stages: anaerobic phosphorus release and aerobic phosphorus uptake; traditional biological nitrogen removal involves two stages: aerobic nitrification and anoxic denitrification. Therefore, traditional wastewater nitrogen and phosphorus removal requires an anaerobic / anoxic / aerobic process (A... 2 O) process is carried out. However, A 2 The O process often faces many problems during operation, including: (1) unstable process operation. Domestic sewage in my country often has a low C / N ratio, which leads to insufficient carbon source in the influent of sewage treatment plants. This will cause denitrifying bacteria and polyphosphate-accumulating bacteria in the water to compete for high-quality carbon source in the initial anaerobic stage of the process, resulting in a decrease in nitrogen and phosphorus removal efficiency. (2) In order to ensure the quality of effluent, additional carbon source needs to be added. This operation will increase the possibility of secondary pollution during sewage treatment, which is contrary to sustainable development. (3) complex process. 2 The O process requires three stages: anaerobic, anoxic, and aerobic. On one hand, to ensure efficient nitrogen and phosphorus removal, the process incorporates two recirculation processes (sludge recirculation from the sedimentation tank to the anaerobic tank and supernatant recirculation from the aerobic tank to the anoxic tank). On the other hand, each stage requires maintaining different DO concentrations to achieve different environmental conditions (anaerobic <0.2 mg / L, anoxic 0.2-0.5 mg / L, aerobic 2-5 mg / L). These two aspects make the entire nitrogen and phosphorus removal process cumbersome and complex. Therefore, it is evident that traditional A... 2 The traditional nitrogen and phosphorus removal methods are time-consuming and energy-intensive. Therefore, there is an urgent need to develop a low-energy-consumption process that can simultaneously remove nitrogen and phosphorus from low C / N wastewater and achieve deep nitrogen and phosphorus removal. Summary of the Invention

[0003] The purpose of this application is to provide a nitrogen and phosphorus removal process and reactor as described in the background art.

[0004] To achieve the above objectives, this application adopts the following technical solution:

[0005] One aspect of this application provides a nitrogen and phosphorus removal process, comprising: a nitrogen and phosphorus removal cycle repeated multiple times, each nitrogen and phosphorus removal cycle comprising:

[0006] Add NH4 to the reactor + and PO4 3- sewage;

[0007] Oxygen is continuously introduced into the wastewater while the wastewater is continuously stirred.

[0008] Stop introducing oxygen into the wastewater and stop stirring the wastewater; add carbon source concentrate to the wastewater.

[0009] After continuously stirring the wastewater for a preset time, let the wastewater stand.

[0010] A preset amount of supernatant is discharged from the reactor;

[0011] After continuously introducing oxygen into the wastewater and continuously stirring the wastewater, the wastewater is allowed to stand.

[0012] Optionally, the addition of NH4 to the reactor... + and PO4 3- The wastewater also contains cobalt chloride (CoCl2), manganese chloride (MnCl2), ferrous sulfate (FeSO4), and ethylenediaminetetraacetic acid (EDTA).

[0013] Optionally, the addition of NH4 to the reactor + and PO4 3- Wastewater includes:

[0014] 5L of wastewater is continuously added to the reactor over 25 minutes, forming a 10L mud-water mixture in the reactor, thereby increasing the NH4 content in the reactor. + The concentration was 50 ± 1.2 mg / L, PO4 3- The concentration was 5 ± 0.5 mg / L.

[0015] Optionally, the step of continuously introducing oxygen into the wastewater and continuously stirring the wastewater includes:

[0016] Oxygen was continuously introduced into the wastewater at a flow rate of 0.7-1.0 L / min for 180 min.

[0017] Optionally, the oxygen supply to the wastewater is stopped and the stirring of the wastewater is stopped, and a carbon source concentrate is added to the wastewater, including:

[0018] 50 ml of carbon source concentrate is continuously fed into the reactor over 10 min, and the pollutant content in the reactor is set to C / N = 3. The carbon source concentrate is prepared from sodium acetate.

[0019] Optionally, after continuously stirring the wastewater for a preset time, allowing the wastewater to stand includes:

[0020] After continuously stirring the wastewater for 30 minutes, let it stand for 6 minutes to allow activated sludge to settle.

[0021] Optionally, discharging a preset amount of supernatant from the reactor includes:

[0022] 5L of wastewater supernatant is continuously discharged from the reactor over 25 minutes to ensure that the reactor contains 5L of mud-water mixture.

[0023] Optionally, the step of continuously introducing oxygen into the wastewater and continuously stirring the wastewater, followed by allowing the wastewater to stand, includes:

[0024] Oxygen was continuously introduced into the wastewater at a flow rate of 0.7-1.0 L / min for 20 minutes, and then the mixture was allowed to stand for 2 hours.

[0025] Optionally, the nitrogen and phosphorus removal process includes:

[0026] Add 2 mL / L of trace element nutrient solution to the reactor;

[0027] The micronutrient solution is composed of: 1.25 g / L ferric chloride, 0.4 g / L copper sulfate, 1.27 g / L manganese chloride, 0.05 g / L sodium molybdate, 0.55 g / L zinc sulfate, 0.4 g / L cobalt chloride, 1.25 g / L ethylenediaminetetraacetic acid, 1.37 g / L calcium chloride, and 44.4 g / L magnesium sulfide.

[0028] Another aspect of this application provides a reactor for the nitrogen and phosphorus removal process provided in this application, including a reaction vessel, a wastewater tank, a carbon source tank, an inlet pump, an outlet pump, an air pump, an aeration head, and a stirring device. The aeration head is disposed inside the reaction vessel, and the stirring device is used to stir the mixture inside the reaction vessel. The carbon source tank is connected to the reaction vessel through the carbon source pump, the wastewater tank is connected to the reaction vessel through the inlet pump, the air pump is connected to the aeration head, and the outlet pump is connected to the reaction vessel.

[0029] Optionally, the reactor provided in this embodiment of the application further includes a PLC control cabinet, and a DO sensor, an ORP sensor, and a pH sensor, all of which are communicatively connected to the PLC control cabinet. The DO sensor, the ORP sensor, and the pH sensor are all installed in the reaction vessel. The inlet pump, the outlet pump, the carbon source pump, the air pump, and the stirring device are all communicatively connected to the PLC control cabinet.

[0030] The technical solution provided in this application can achieve at least one of the following beneficial effects:

[0031] The nitrogen and phosphorus removal process and reactor provided in this application combine aerobic nitrification and aerobic phosphorus release in the aerobic stage, achieving simultaneous removal of ammonia nitrogen and release of phosphorus. This fully utilizes aeration, eliminating the need for an anaerobic stage to achieve phosphorus release and reducing the complexity of wastewater treatment operations. Furthermore, in the anoxic stage, it combines anoxic denitrification and denitrification phosphorus uptake, utilizing the same intermediate product for nitrogen removal and the same substance required for phosphorus removal. Specifically, the intermediate product of short-cut nitrification is nitrite nitrogen, and the electron acceptor for denitrification phosphorus removal is also nitrite nitrogen. By combining short-cut denitrification with denitrification phosphorus removal, "one carbon source, two uses" is achieved in the anoxic stage, improving the utilization rate of carbon sources during wastewater treatment, avoiding the need for additional carbon source addition in the anoxic stage, and reducing the possibility of secondary pollution during wastewater treatment. At the same time, it shortens the nitrogen and phosphorus removal path by combining aerobic nitrification with aerobic phosphorus release and anoxic denitrification with phosphorus uptake, effectively shortening the nitrogen and phosphorus removal path.

[0032] The additional technical features and advantages of this application will become more apparent from the following description or from practical application. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the specific embodiments of this application, the accompanying drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0034] Figure 1 A schematic flow diagram of one embodiment of the denitrification and phosphorus removal process provided in this application.

[0035] Figure 2 A graph showing the pollutant changes during one cycle of the nitrogen and phosphorus removal process provided in this application embodiment;

[0036] Figure 3 This is a diagram showing the long-term P treatment status of the denitrification and phosphorus removal process provided in the embodiments of this application;

[0037] Figure 4 This is a diagram showing the long-term TN treatment status of the denitrification and phosphorus removal process provided in the embodiments of this application;

[0038] Figure 5 This is a schematic diagram of one embodiment of the reactor provided in this application.

[0039] Figure label:

[0040] 01. PLC control cabinet; 02. Aeration head;

[0041] 03. Reaction vessel; 04. DO sensor;

[0042] 05. pH sensor; 06. ORP sensor;

[0043] 08. Agitator; 09. Water pump;

[0044] 10. Air pump; 11. Sewage tank;

[0045] 12. Inlet pump; 13. Carbon source tank;

[0046] 14. Carbon source pump. Detailed Implementation

[0047] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0048] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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 mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0050] like Figure 1 As shown, one aspect of this application provides a nitrogen and phosphorus removal process, comprising: multiple consecutive nitrogen and phosphorus removal cycles, each of the nitrogen and phosphorus removal cycles comprising:

[0051] Step 100: Add NH4+ to the reactor. + and PO4 3- sewage;

[0052] Step 200: Continuously introduce oxygen into the wastewater and continuously stir the wastewater;

[0053] Step 300: Stop introducing oxygen into the wastewater and stop stirring the wastewater; add carbon source concentrate to the wastewater.

[0054] Step 400: After continuously stirring the wastewater for a preset time, let the wastewater stand.

[0055] Step 500: Discharge a preset amount of supernatant from the reactor;

[0056] Step 600: After continuously introducing oxygen into the wastewater and continuously stirring the wastewater, let the wastewater stand.

[0057] In this embodiment of the application, "multiple times" means at least twice.

[0058] The nitrogen and phosphorus removal process provided in this application utilizes short-cut nitrification and denitrification (PND) and enhanced biological phosphorus removal (EBPR) processes. Specifically, the nitrogen removal pathway of the short-cut nitrification and denitrification process involves removing NH4 under aerobic conditions. + -N is oxidized to NO2 - -N, and then enter the hypoxic phase to complete NO2 production. - The denitrification reaction from -N to N2. Compared to traditional nitrification-denitrification processes, the PND process eliminates the need for NO3. - -N repeats in two stages, from NH4 + -N→NO2 - -N→NO3 - -N→NO2 - -N→N2 shortens to NH4 + -N→NO2 - -N→N2. Therefore, the PND process can reduce the aeration energy consumption in the nitrification stage and the carbon source addition in the denitrification stage. The core microorganisms in the enhanced biological phosphorus removal process are polyphosphate-accumulating bacteria (PAOs). These bacteria release polyphosphate from their cells into the water as PO4 under anaerobic conditions. 3- -P exists in water bodies and, under aerobic conditions, converts PO4 into 2-hydroxyl radicals. 3- -P is absorbed into the body. Through two stages—anaerobic phosphorus release and aerobic excess phosphorus uptake—PO4 in the water is removed. 3--P accumulates in activated sludge and is then discharged from the system. Excessive phosphorus uptake during aerobic processes requires the consumption of intracellular PHA, which is derived from volatile fatty acids (VFA) in the anaerobic water.

[0059] The nitrogen and phosphorus removal process provided in this application can also be called a short-cut nitrification-denitrification simultaneous nitrogen and phosphorus removal process. The phosphorus removal pathway consists of two stages: phosphorus release in an aerobic stage and phosphorus uptake in an anoxic stage. In the aerobic stage, microorganisms absorb organic matter in the water and synthesize glycogen (Gly). The energy generated in this process is used to release PO4 from within the cells. 3- -P enters the water body, therefore, under aerobic conditions, PO4 in the water body 3- -P concentration increases. In the anoxic zone, microorganisms utilize NO in the water. 2- -N acts as an electron acceptor, utilizing the energy stored in the aerobic zone (Gly) and the carbon source (COD) in the water to absorb PO4 from the water. 3- -P is absorbed into the cells. Aerobic phosphorus release and anoxic phosphorus uptake constitute a complete phosphorus removal process, ultimately achieving the goal of removing phosphorus from wastewater through the discharge of excess sludge. Therefore, under suitable conditions, cyclically carrying out the aerobic / anoxic process can combine short-cut nitrification-denitrification denitrification with aerobic phosphorus release / anoxic phosphorus uptake processes, ultimately achieving simultaneous two-stage nitrogen and phosphorus removal.

[0060] The nitrogen and phosphorus removal process provided in this application combines aerobic nitrification with aerobic phosphorus release in the aerobic stage, achieving simultaneous removal of ammonia nitrogen and release of phosphorus. This fully utilizes aeration energy consumption, eliminates the need for an anaerobic stage to achieve phosphorus release, and reduces the complexity of wastewater treatment operations. Furthermore, in the anoxic stage, it combines anoxic denitrification with denitrification phosphorus uptake, utilizing the same substances required for both nitrogen and phosphorus removal. That is, the intermediate product of short-cut nitrification is nitrite nitrogen, and the electron acceptor for denitrification phosphorus removal is also nitrite nitrogen. By combining short-cut denitrification with denitrification phosphorus removal, "one carbon source for two uses" is achieved in the anoxic stage, improving the utilization rate of carbon sources during wastewater treatment, avoiding the need for additional carbon source addition in the anoxic stage, and reducing the possibility of secondary pollution during wastewater treatment. At the same time, it shortens the nitrogen and phosphorus removal pathways by combining aerobic nitrification with aerobic phosphorus release and anoxic denitrification with phosphorus uptake, effectively shortening the nitrogen and phosphorus removal pathways.

[0061] Optionally, in step 100, the wastewater may also contain cobalt chloride (CoCl2), manganese chloride (MnCl2), ferrous sulfate (FeSO4), and ethylenediaminetetraacetic acid (EDTA).

[0062] Optionally, step 100 includes:

[0063] 5L of wastewater is continuously added to the reactor over 25 minutes, forming a 10L mud-water mixture in the reactor, thereby increasing the NH4 content in the reactor. + The concentration was 50 ± 1.2 mg / L, PO4 3- The concentration was 5 ± 0.5 mg / L.

[0064] Optionally, step 200 includes:

[0065] Oxygen was continuously introduced into the wastewater at a flow rate of 0.7-1.0 L / min for 180 min.

[0066] This stage involves short-range nitration and phosphorus release reactions, such as... Figure 2 As shown in the diagram, ammonia nitrogen is gradually oxidized to nitrite nitrogen in the water body during the aerobic stage. During this process, the phosphorus (P) concentration in the water gradually increases. The influent P concentration was 4.85 mg / L, and after aerobic nitrification and phosphorus release, the highest P concentration in the aerobic stage reached 13.59 mg / L. Figure 2 It can be seen that the accumulation rate of nitrite nitrogen is good during this process, indicating that the PND process is effective.

[0067] Optionally, step 300 includes:

[0068] 50 ml of carbon source concentrate is continuously fed into the reactor over 10 min, and the pollutant content in the reactor is set to C / N = 3. The carbon source concentrate is prepared from sodium acetate.

[0069] Optionally, step 400 includes:

[0070] After continuously stirring the wastewater for 30 minutes, let it stand for 6 minutes to allow activated sludge to settle.

[0071] This stage involves anoxic denitrification and phosphorus uptake reactions, such as... Figure 2 As shown, the nitrite nitrogen concentration gradually decreases in the anoxic zone, while the phosphorus (P) concentration in the water gradually decreases as denitrification proceeds. The initial P concentration in the anoxic zone was 12.14 mg / L; after phosphorus uptake through anoxic denitrification, the P concentration in the water decreased to 0.48 mg / L at the end of the anoxic zone. Figure 2 It can be seen that the removal of nitrite nitrogen and phosphorus is effective during this process, indicating that the DPR process is effective. The anoxic phase lasts for 30 minutes, and the precipitation phase lasts for 6 minutes.

[0072] Optionally, step 500 includes:

[0073] 5L of wastewater supernatant is continuously discharged from the reactor over 25 minutes to ensure that the reactor contains 5L of mud-water mixture.

[0074] Optionally, step 600 includes:

[0075] Oxygen was continuously introduced into the wastewater at a flow rate of 0.7-1.0 L / min for 20 minutes, and then the mixture was allowed to stand for 2 hours.

[0076] In this embodiment, a complete cycle of operation takes 8 hours, and 3 cycles are run per day. Long-term operational results are as follows... Figure 3 As shown. By Figure 3 It can be seen that the highest phosphorus release in the aerobic stage can reach 11.87 mg / L, with good phosphorus removal effect and a phosphorus removal rate of 95.67%. TN removal rate can be stably maintained at around 98.89%, nitrite accumulation rate can be stably maintained above 95%, and NO2... - -N and NO3 - -N can be completely removed. Specific water output details are as follows: Figure 3 and Figure 4 As shown.

[0077] Optionally, the nitrogen and phosphorus removal process provided in the embodiments of this application further includes:

[0078] Add 2 mL / L of trace element nutrient solution to the reactor;

[0079] The micronutrient solution is composed of: 1.25 g / L ferric chloride, 0.4 g / L copper sulfate, 1.27 g / L manganese chloride, 0.05 g / L sodium molybdate, 0.55 g / L zinc sulfate, 0.4 g / L cobalt chloride, 1.25 g / L ethylenediaminetetraacetic acid, 1.37 g / L calcium chloride, and 44.4 g / L magnesium sulfide.

[0080] like Figure 5 As shown, another aspect of this application provides a reactor applied to the nitrogen and phosphorus removal process provided in the embodiments of this application, including a reaction vessel 03, a wastewater tank 11, a carbon source tank 13, an inlet pump 12, an outlet pump 09, a carbon source pump 14, an air pump 10, an aeration head 02, and a stirring device 08. The aeration head 02 is disposed in the reaction vessel 03, and the stirring device 08 is used to stir the mixture in the reaction vessel 03. The carbon source tank 13 is connected to the reaction vessel 03 through the carbon source pump 14, the wastewater tank 11 is connected to the reaction vessel 03 through the inlet pump 12, the air pump 10 is connected to the aeration head 02, and the outlet pump 09 is connected to the reaction vessel 03.

[0081] The reactor provided in this application allows for the chemical reactions in the denitrification and phosphorus removal process to be carried out within the reaction vessel 03. A carbon source concentrate is added to the reaction vessel 03 via a carbon source pump 14, wastewater from a wastewater tank 11 is fed into the reaction vessel 03 via a wastewater tank 11, air is introduced into the reaction vessel 03 via an air pump 10 and an aeration head 02, the mixture within the reaction vessel 03 is stirred by a stirring device 08, and the mixture is discharged from the reaction vessel 03 via an outlet pump 09, thus enabling the denitrification and phosphorus removal process to proceed smoothly. The inlet pump 12, outlet pump 09, and carbon source pump 14 are all preferably peristaltic pumps.

[0082] Optionally, the reactor provided in this embodiment of the application further includes a PLC control cabinet 01, and a DO sensor 04, an ORP sensor 06, and a pH sensor 05, all of which are communicatively connected to the PLC control cabinet 01. The DO sensor 04, the ORP sensor 06, and the pH sensor 05 are all installed in the reaction vessel 03. The inlet pump 12, the outlet pump 09, the carbon source pump 14, the air pump 10, and the stirring device 08 are all communicatively connected to the PLC control cabinet 01.

[0083] The reactor provided in this embodiment is preferably an SBR reactor made of plexiglass, with a volume of 12L and an effective working volume of 10L. The reactor dimensions are preferably 40cm high and 20cm inner diameter. The preferred exchange ratio is 0.5, with influent and effluent supplied via a peristaltic pump and hoses. An air pump 10 is used for aeration, and a mechanical stirrer is configured within the reactor for forced aeration. The aeration rate in the aerobic section is 0.7-1.0L / min, and the sludge age is 14d. This experiment utilizes a wastewater biological denitrification intelligent control system combining sensors and a PLC control cabinet 01 for real-time control. Figure 5 As shown, the reactor is equipped with DO sensor 04, ORP sensor 06 and pH sensor 05, all of which are connected to PLC control cabinet 01. The changes in water parameters are monitored in real time through wastewater biological denitrification intelligent control software. At the same time, the PLC controller is equipped with a switch to control the influent, stirring, aeration, COD addition and discharge of the SBR through monitoring data.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A nitrogen and phosphorus removal process, characterized in that, include: A series of repeated nitrogen and phosphorus removal cycles, each of which includes: Adding NH4 to the reactor + and PO4 3- sewage; Oxygen is continuously introduced into the wastewater while the wastewater is continuously stirred, and aerobic nitrification and aerobic phosphorus release are carried out simultaneously. Stop introducing oxygen into the wastewater and stop stirring the wastewater. Add carbon source concentrate to the wastewater and simultaneously carry out anoxic denitrification and denitrification phosphorus uptake. After continuously stirring the wastewater for a preset time, let the wastewater stand. A preset amount of supernatant is discharged from the reactor; After continuously introducing oxygen into the remaining wastewater in the reactor and continuously stirring the wastewater, the wastewater is allowed to stand.

2. The nitrogen and phosphorus removal process according to claim 1, characterized in that, The addition of NH4 to the reactor + and PO4 3- The wastewater also contains cobalt chloride (CoCl2), manganese chloride (MnCl2), ferrous sulfate (FeSO4), and ethylenediaminetetraacetic acid (EDTA).

3. The nitrogen and phosphorus removal process according to claim 1, characterized in that, The addition of NH4 to the reactor + and PO4 3- Wastewater includes: 5L of wastewater is continuously added to the reactor over 25 minutes, forming a 10L mud-water mixture in the reactor, thereby increasing the NH4 content in the reactor. + The concentration was 50 ± 1.2 mg / L, PO4 3- The concentration was 5 ± 0.5 mg / L.

4. The nitrogen and phosphorus removal process according to claim 1, characterized in that, Continuously introducing oxygen into the wastewater and continuously agitating the wastewater includes: Oxygen was continuously introduced into the wastewater at a flow rate of 0.7-1.0 L / min for 180 min.

5. The nitrogen and phosphorus removal process according to claim 1, characterized in that, Stop introducing oxygen into the wastewater and stop stirring the wastewater, then add a carbon source concentrate to the wastewater, including: 50 ml of carbon source concentrate is continuously fed into the reactor over 10 min. The pollutant content in the reactor is C / N = 3. The carbon source concentrate is prepared from sodium acetate.

6. The nitrogen and phosphorus removal process according to claim 1, characterized in that, After continuously stirring the wastewater for a preset time, the wastewater is allowed to stand, including: After continuously stirring the wastewater for 30 minutes, let it stand for 6 minutes to allow activated sludge to settle.

7. The nitrogen and phosphorus removal process according to claim 1, characterized in that, Discharging a predetermined amount of supernatant from the reactor includes: 5L of wastewater supernatant is continuously discharged from the reactor over 25 minutes to ensure that the reactor contains 5L of mud-water mixture.

8. The nitrogen and phosphorus removal process according to claim 1, characterized in that, After continuously introducing oxygen and stirring the wastewater, the wastewater is allowed to stand, including: Oxygen was continuously introduced into the wastewater at a flow rate of 0.7-1.0 L / min for 20 minutes, and then the mixture was allowed to stand for 2 hours.

9. The nitrogen and phosphorus removal process according to any one of claims 1 to 8, characterized in that, include: Add 2 mL / L of trace element nutrient solution to the reactor; The micronutrient solution is composed of: 1.25 g / L ferric chloride, 0.4 g / L copper sulfate, 1.27 g / L manganese chloride, 0.05 g / L sodium molybdate, 0.55 g / L zinc sulfate, 0.4 g / L cobalt chloride, 1.25 g / L ethylenediaminetetraacetic acid, 1.37 g / L calcium chloride, and 44.4 g / L magnesium sulfide.

10. A reactor, characterized in that, The nitrogen and phosphorus removal process according to any one of claims 1 to 9 includes a reaction vessel, a wastewater tank, a carbon source tank, an inlet pump, an outlet pump, a carbon source pump, an air pump, an aeration head, and a stirring device. The aeration head is disposed inside the reaction vessel, and the stirring device is used to stir the mixture inside the reaction vessel. The carbon source tank is connected to the reaction vessel through the carbon source pump, the wastewater tank is connected to the reaction vessel through the inlet pump, the air pump is connected to the aeration head, and the outlet pump is connected to the reaction vessel. The reactor also includes a PLC control cabinet, and a DO sensor, an ORP sensor, and a pH sensor, all of which are communicatively connected to the PLC control cabinet. The DO sensor, the ORP sensor, and the pH sensor are all installed in the reaction vessel. The inlet pump, the outlet pump, the carbon source pump, the air pump, and the stirring device are all communicatively connected to the PLC control cabinet.

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