Sewage treatment plant carbon source self-supply method and system based on electromagnetic wave technology

Abstract

The invention belongs to the technical field of sewage treatment, and particularly relates to a sewage treatment plant carbon source self-supply method and system based on an electromagnetic wave technology. The A / A / O reactor comprises an anaerobic tank, an anoxic tank and an aerobic tank which are sequentially communicated with one another; the water inlet pipeline is communicated with the anaerobic tank; the secondary sedimentation tank is communicated with the aerobic tank and is provided with a sludge outlet; the first electromagnetic wave loading unit is provided with a first flow channel, and two ends of the first flow channel are respectively communicated with the water inlet pipeline and the sludge outlet through sludge return pipes; and the second electromagnetic wave loading unit is provided with a second flow channel, and two ends of the second flow channel are respectively communicated with the anoxic tank and the aerobic tank through nitrification liquid return pipelines. By synergistically loading the return sludge and the internal reflux nitrification liquid, in-situ release and efficient utilization of organic matters can be realized, so that self-supply of a carbon source of a sewage treatment plant is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and in particular relates to a method and system for supplying carbon sources to sewage treatment plants based on electromagnetic wave technology. Background Art

[0002] The A / A / O process, a mainstream biological denitrification and phosphorus removal technology, effectively removes organic matter, nitrogen, and phosphorus pollutants from wastewater by forming an anaerobic-anoxic-aerobic system. It is widely used in urban sewage treatment plants. However, during operation, the system often faces the bottleneck of insufficient carbon source, resulting in reduced denitrification efficiency.

[0003] In current engineering practice, the method of adding external carbon sources is generally used to alleviate the problem of insufficient carbon sources. For example, chemical carbon sources such as sodium acetate, methanol, and glucose are added to meet the electron donor needs of denitrifying bacteria. These organic substances are easily absorbed and utilized by denitrifying microorganisms, which can significantly improve the denitrification efficiency in the short term. However, the cost of adding external carbon sources is high and requires long-term continuous addition, which significantly increases the operating costs of sewage treatment plants. It is estimated that in large sewage treatment plants, the cost of adding external carbon sources can account for more than 20% of the total operating costs, becoming the third largest operating burden after energy consumption and sludge treatment. At the same time, the control accuracy of the carbon source addition process is low, and it is easy for insufficient addition to affect the treatment effect, or excessive addition to cause problems such as increased effluent COD and sludge bulking, bringing potential secondary pollution risks. Therefore, exploring more economical, safe and controllable carbon source supply strategies has become the current research focus of sewage treatment technology optimization.

[0004] The introduction of electromagnetic wave loading technology offers a new solution for achieving carbon source self-supply. Leveraging the high-frequency response of polar molecules under electromagnetic fields, this technology demonstrates a significant dissolution effect within the sludge treatment environment. Specifically, the high-frequency electromagnetic waves cause dipolarization and high-speed rotation of water molecules within and between cells of the sludge, generating microscopic shear and impact effects that mechanically disrupt microbial cell walls, triggering the release of intracellular organic matter and significantly increasing the content of dissolved organic matter (such as volatile fatty acids and low-molecular-weight organic acids) in the sludge supernatant. These soluble organic matter possesses excellent bioavailability and can directly serve as electron donors for denitrification, satisfying the carbon source demand during the anoxic phase. Compared to traditional external application methods, electromagnetic wave-stimulated carbon source release from cells requires no external reagents and relies on endogenous sources for supply, effectively reducing operating costs and improving environmental friendliness.

[0005] Therefore, rationally utilizing the dissolution effect of electromagnetic wave technology to ensure sufficient release of organic matter is one of the important potential paths to achieve carbon source supply in sewage treatment plants. Summary of the Invention

[0006] The present invention addresses the shortcomings of the prior art by providing a method and system for carbon source self-supply in sewage treatment plants using electromagnetic wave technology. The inventors discovered that by synergistically loading return sludge and internal reflow nitrification liquid with electromagnetic waves, organic matter can be released in situ and efficiently utilized, thereby achieving self-supply of carbon sources in sewage treatment plants.

[0007] The technical solution of the present invention to solve the above technical problems is as follows:

[0008] A carbon source supply system for a sewage treatment plant based on electromagnetic wave technology, comprising:

[0009] The A / A / O reactor comprises an anaerobic tank, an anoxic tank and an aerobic tank which are connected in sequence;

[0010] A water inlet pipe connected to the anaerobic tank;

[0011] A secondary sedimentation tank connected to the aerobic tank, wherein the secondary sedimentation tank has a mud outlet;

[0012] A first electromagnetic wave loading unit has a first flow channel, with both ends of the first flow channel connected to the water inlet pipeline and the mud outlet through a sludge return pipe respectively;

[0013] and a second electromagnetic wave loading unit, which has a second flow channel, wherein both ends of the second flow channel are connected to the anoxic tank and the aerobic tank respectively through a nitrification liquid reflux pipeline.

[0014] Based on the above technical solution:

[0015] The first electromagnetic wave loading unit can continuously excite the returned sludge with electromagnetic waves, which can promote the release of organic matter;

[0016] The second electromagnetic wave loading unit can continuously excite the refluxed nitrification liquid with electromagnetic waves, which can promote the release of organic matter;

[0017] The stimulated return sludge and stimulated return nitrification solution work synergistically in the A / A / O reactor, which can significantly increase the SCOD of the return sludge and at the same time significantly increase the SCOD of the supernatant of the nitrification solution.

[0018] Furthermore: an agitator is provided in the anaerobic tank.

[0019] Furthermore: a stirrer is provided in the anoxic tank.

[0020] Furthermore: an aeration plate is provided in the aerobic tank, and the aeration plate is connected to an air pump.

[0021] Furthermore: a peristaltic pump is provided between the first electromagnetic wave loading unit and the water inlet pipeline.

[0022] Furthermore: a peristaltic pump is provided in communication between the second electromagnetic wave loading unit and the anoxic tank.

[0023] Furthermore: a return pipeline for direct sludge return is provided between the secondary sedimentation tank and the water inlet pipeline.

[0024] Furthermore: a reflux pipeline for direct reflux of the nitrification liquid is provided between the aerobic tank and the anoxic tank.

[0025] The present invention also provides a method for supplying carbon origin to a sewage treatment plant based on electromagnetic wave technology, which comprises the following steps:

[0026] 1) Use A / A / O reactor to treat sewage and operate stably for a period of time;

[0027] 2) A portion (10-30%, preferably 15-25%) of the sludge obtained from the secondary sedimentation tank is introduced into the anaerobic tank as return sludge, and the return sludge is continuously excited by electromagnetic waves to increase the SCOD content of the supernatant of the return sludge output by the first electromagnetic wave loading unit, for example, to 910-920%, and to increase the SCOD content of the subsequent return nitrification liquid, for example, to 75-85%;

[0028] 3) A portion (5-20%, preferably 5-15%) of the nitrification liquid from the aerobic tank is introduced into the anoxic tank as the reflux nitrification liquid, and the reflux nitrification liquid is continuously excited by electromagnetic waves, thereby increasing the SCOD content of the reflux nitrification liquid output by the second electromagnetic wave loading unit, for example, to 1045-1055%, and increasing the SCOD content of the supernatant of the reflux sludge output from the subsequent first electromagnetic wave loading unit, for example, to 990-1000%.

[0029] Based on the above technical solution:

[0030] Continuous electromagnetic wave excitation of the returned sludge can promote the release of organic matter;

[0031] Continuous electromagnetic wave excitation of the refluxed nitrification solution can promote the release of organic matter;

[0032] The stimulated return sludge and stimulated return nitrification solution work synergistically in the A / A / O reactor, which can significantly increase the SCOD of the return sludge and at the same time significantly increase the SCOD of the supernatant of the nitrification solution.

[0033] In the above technical solution, steps 2) to 3) can be repeated until all sewage is treated.

[0034] In the above technical solution, the sludge and / or nitrification liquid that has not been loaded with electromagnetic waves can be refluxed.

[0035] Specifically:

[0036] The power of continuous electromagnetic wave excitation for the return sludge is 240-280 W, preferably 260 W;

[0037] The time for continuous excitation of the electromagnetic wave on the return sludge is 40-50 s, preferably 45 s;

[0038] Return sludge accounts for 15-25% of the total sludge, preferably 20%;

[0039] The frequency of the continuous excitation of the electromagnetic wave for the return sludge is 2400-2500 MHz, preferably 2450 MHz.

[0040] Specifically:

[0041] The power of the electromagnetic wave continuous excitation of the reflux nitration liquid is 360-440 W, preferably 400 W;

[0042] The time for continuous electromagnetic wave excitation of the reflux nitrification liquid is 70-80 s, preferably 75 s;

[0043] The reflux nitrification liquid accounts for 5-15% of the total nitrification liquid, preferably 10%;

[0044] The frequency of the electromagnetic wave continuous excitation of the reflux nitration liquid is 2400-2500 MHz, preferably 2450 MHz.

[0045] Specifically:

[0046] After the A / A / O reactor has been running stably for 25-35 days, preferably 30 days, continuous electromagnetic wave excitation is performed;

[0047] The working temperature is 20-30°C, preferably 25°C;

[0048] The dissolved oxygen in the aerobic tank is 1.60-1.70 mg / L, preferably 1.66 mg / L;

[0049] The sludge return ratio is 65-75%, preferably 70%;

[0050] The nitration liquid reflux ratio is 280-320%, preferably 300%;

[0051] The sludge retention time is 14-16 days, preferably 15 days.

[0052] Specifically, the retention time of the anaerobic tank is 1.8-2.2.

[0053] Specifically, the residence time of the anoxic tank is 2.8-3.2.

[0054] Specifically, the retention time of the aerobic pool is 5.6-6.0.

[0055] The beneficial effects of the present invention are:

[0056] 1. This invention uses electromagnetic waves to synergistically load the return sludge and internal return nitrification liquid. The energy radiated by the microorganisms stimulates the high-speed movement of polar molecules within and between cells, triggering cell structure rupture and releasing intracellular organic matter into the liquid phase. This significantly increases the concentration of bioavailable dissolved organic matter in the system and increases the system's organic load. The released organic matter is rapidly converted into low-molecular organic acids in the anaerobic stage, directly serving as electron donors for denitrification, effectively supplementing the carbon source supply, improving the imbalance in the carbon-nitrogen ratio, and improving the system's denitrification efficiency.

[0057] 2. This invention employs a coordinated loading strategy, acting separately on the return sludge and the internal return nitrification solution, to simultaneously induce the release of intracellular high-molecular organic matter in different return paths, thereby establishing a multi-point distributed and dynamically balanced carbon source supply mechanism within the system. Simultaneously, through dual-channel carbon source supply, rapid response and regulation to load fluctuations are achieved, enhancing the stability and continuity of the system's carbon source, improving the A / A / O process's adaptability to complex operating conditions, and comprehensively optimizing carbon source efficiency, denitrification performance, and operational flexibility. This approach has significant practical value and potential for engineering promotion.

[0058] 3. This invention achieves closed-loop regulation of the extraction, release, and utilization of organic carbon sources within the system, eliminating reliance on traditional chemical carbon sources, significantly reducing operating costs, and enhancing the green and low-carbon nature of wastewater treatment plants. Furthermore, the electromagnetic wave loading process does not involve the addition of exogenous chemical agents, ensuring excellent environmental compatibility and operational safety. This provides a feasible and efficient technical path for constructing self-sufficient carbon source supply systems for large-scale wastewater treatment plants.

[0059] 4. Realize the in-situ release and efficient utilization of organic matter, and solve the technical problems of traditional carbon source supply methods such as high cost, strong dependence and difficulty in regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 This is a structural diagram of the carbon source supply system for a sewage treatment plant based on electromagnetic wave technology of the present invention.

[0061] Figure 2 The SCOD concentration data diagram of the return sludge and nitrification liquid supernatant loaded with electromagnetic waves under different working conditions.

[0062] Figure 3 Figure 2 shows the fluorescence spectrum parameters of sludge supernatant before and after electromagnetic wave loading.

[0063] Attachment Figure 1 The components represented by the reference numbers are as follows:

[0064] 1. Anaerobic tank, 2. Anoxic tank, 3. Aerobic tank, 4. Secondary sedimentation tank, 5. First electromagnetic wave loading unit, 6. Second electromagnetic wave loading unit. DETAILED DESCRIPTION

[0065] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0066] Unless otherwise specified, the test methods in the examples are conventional methods; the materials and reagents used are commercially available unless otherwise specified.

[0067] The sewage water quality indicators are: COD: 240~250mg / L, TN: 35~40mg / L, TP: 3.5~4mg / L, pH: 6~8.

[0068] During the reactor startup phase, the return sludge from the Wuhan Longwangzui Wastewater Treatment Plant was used as inoculated sludge.

[0069] In a specific embodiment, Figure 1 As shown, the carbon source supply system for a sewage treatment plant based on electromagnetic wave technology includes: an A / A / O reactor, a water inlet pipeline, a secondary sedimentation tank 4, a first electromagnetic wave loading unit 5, and a second electromagnetic wave loading unit 6. The A / A / O reactor includes an anaerobic tank 1, an anoxic tank 2, and an aerobic tank 3, which are connected in sequence.

[0070] The water inlet pipe connects to the anaerobic tank 1. The secondary sedimentation tank 4 connects to the aerobic tank 3 and has a sludge outlet. The first electromagnetic wave loading unit 5 has a first flow channel, with both ends of the first flow channel connected to the water inlet pipe and the sludge outlet respectively through sludge return pipes. The second electromagnetic wave loading unit 6 has a second flow channel, with both ends of the second flow channel connected to the anoxic tank 2 and the aerobic tank 3 respectively through the nitrification liquid return pipe.

[0071] The first electromagnetic wave loading unit 5 and the second electromagnetic wave loading unit 6 can respectively adopt the following existing technologies: a box-type electromagnetic wave generator is used, a flow channel is set through the box, and the flow channel material is a silicone tube. The through connection between the flow channel and the electromagnetic wave generator is sealed.

[0072] In order to further evenly mix, an agitator is provided in the anaerobic tank 1 and an agitator is provided in the anoxic tank 2.

[0073] In order to further allow the return sludge and return nitrification liquid to flow at an appropriate speed, a peristaltic pump is provided between the first electromagnetic wave loading unit 5 and the water inlet pipeline, and a peristaltic pump is provided between the second electromagnetic wave loading unit 6 and the anoxic tank 2.

[0074] In a specific embodiment, the method for carbon source supply in a sewage treatment plant based on electromagnetic wave technology can be implemented and verified according to the following steps:

[0075] Step 1: Set up a carbon source supply system for a sewage treatment plant based on electromagnetic wave technology;

[0076] Step 2: By controlling the electromagnetic wave loading conditions (loading power, loading time) and adjusting the amount of returned sludge loaded, a comparative test is conducted to detect changes in the organic matter content of the sludge supernatant and the nitrification solution supernatant before and after the electromagnetic wave loading of the returned sludge;

[0077] Step 3: Based on the electromagnetic wave loading of the return sludge in step 2, the loading power, loading time and loading percentage of the electromagnetic wave loading of the nitrification liquid are adjusted, and the change in the organic matter content of the supernatant of the nitrification liquid is detected under the condition of the electromagnetic wave synergistic loading of the return sludge and the nitrification liquid.

[0078] Specifically, in step one: the reactors of the anaerobic, anoxic and aerobic parts are made of organic glass to ensure sealing; the water inlet pump, outlet pipe and regulating valve are installed to ensure flow controllable; a stirring device is installed in the anaerobic and anoxic areas to ensure uniform mixing; an aeration system is set up in the aerobic area to adjust the gas flow; and the loading frequency of the electromagnetic wave loading unit is set.

[0079] Specifically, step 2 includes: after the system has been running stably for 30 days, adding a branch pipe of the electromagnetic wave loading device to the return sludge pipeline, connecting the sludge inlet and outlet pipes of the continuous flow 2450 MHz electromagnetic wave loading device, leaving a sampling port, and adding a peristaltic pump to the sludge inlet pipeline, and adjusting the flow rate by adjusting the speed of the peristaltic pump.

[0080] During the experiment, the electromagnetic wave loading power was varied by adjusting the input voltage, the loading time was altered by adjusting the branch pipe length (for example, by converting a straight pipe into a curved one to increase the path length), and the loading percentage was varied by adjusting the peristaltic pump speed. Under the defined loading conditions, the SCOD content of the supernatant of the sludge sample and the nitrification solution was measured before and after loading. Return sludge, not subjected to electromagnetic wave loading, was directly returned from the secondary clarifier to the front end through the original sludge return pipe.

[0081] Specifically, the step three includes: based on the working condition of electromagnetic wave loading sludge, adding a continuous flow 2450 MHz electromagnetic wave loading internal reflux nitrification liquid line on the nitrification liquid return line of the reactor, and conducting electromagnetic wave loading A / A / O internal and external reflux system operation test. During the test, the loading conditions were changed by adjusting the input voltage, adjusting the branch pipe length, and the peristaltic pump speed, and the SCOD content of the supernatant of the loaded nitrification liquid was detected under the set loading conditions. The remaining nitrification liquid that was not loaded with electromagnetic waves directly passed through the original nitrification liquid return pipe and flowed back from the aerobic tank to the anoxic tank. At the same time, sludge samples from each stage of the A / A / O process under three working conditions: the system was not loaded with electromagnetic waves, loaded with reflux sludge, and coordinated with internal and external reflux, and three-dimensional fluorescence spectral analysis was performed.

[0082] Example

[0083] 1. The water treatment capacity of the A / A / O system is 1.12 L / h. The effective volume of the main reaction zone is 10.9 L, of which the effective volumes of the anaerobic tank, anoxic tank, and aerobic tank are 2.2 L, 2.2 L, and 6.5 L, respectively, and the hydraulic retention times are 2, 3, and 5.8 h, respectively; the effective volume of the secondary sedimentation tank is 7.0 L.

[0084] 2. The anaerobic and anoxic tanks are equipped with electric stirrers, and the aerobic tanks are equipped with aeration discs at the bottom. The aeration rate is adjusted by a rotor flowmeter. The anaerobic, anoxic, aerobic, and sedimentation tanks are connected by PVC pipes, and the flow of the sludge mixture is controlled by gravity.

[0085] 3. The test temperature was controlled at around 25°C, the DO concentration in the aerobic tank was controlled at 1.66 mg / L, the sludge return ratio was set to 70%, the nitrification solution return ratio was set to 300%, and the sludge retention time was set to 15 days.

[0086] 4. After the system has been running stably for 30 days, load the return sludge and return nitrification liquid.

[0087] Setting different operating parameters to operate the A / A / O system can increase the organic load of the system. The specific information is as follows:

[0088] Experiment 1: Under conditions I (no loading), II (loading return sludge: P = 260 W, T = 45 s, loading percentage = 20%), and III (loading return sludge: P = 260 W, T = 45 s, loading percentage = 20%; loading return nitrification solution: P = 400 W, T = 75 s, loading percentage = 10%), the potassium dichromate method was used to detect the SCOD concentration of the supernatant in the return sludge sample (output from the first electromagnetic wave loading unit) and the SCOD concentration of the supernatant in the nitrification solution (output from the second electromagnetic wave loading unit).

[0089] Experiment 2: Under conditions I (no loading), II (loading return sludge: P = 260 W, T = 45 s, loading percentage = 20%), and III (loading return sludge: P = 260 W, T = 45 s, loading percentage = 20%; loading return nitrification solution: P = 400 W, T = 75 s, loading percentage = 10%), the fluorescence spectra of dissolved organic matter in EPS were measured using a fluorescence spectrophotometer.

[0090] During the above experiment:

[0091] Condition I: The system is operated for 30 days at the initial condition without loading return sludge and return nitrification liquid, and then the data are measured and averaged.

[0092] In working condition I, the data measured were from the sludge return pipe and the nitrification liquid return pipe without electromagnetic wave loading;

[0093] In working condition II, the data measured are from the sludge return pipe loaded with electromagnetic waves and the nitrification liquid return pipe not loaded with electromagnetic waves;

[0094] In working condition III, the data measured are in the sludge return pipe loaded with electromagnetic waves and the nitrification liquid return pipe loaded with electromagnetic waves.

[0095] Test results:

[0096] Under different electromagnetic wave loading conditions, the SCOD dissolution effects of the sludge supernatant and nitrification liquid supernatant before and after loading are shown in Table 1.

[0097] Table 1 SCOD concentration of return sludge and nitrification liquid supernatant loaded by electromagnetic wave under different working conditions

[0098]

[0099] The experimental data in Table 1 show that, in Condition II, after irradiating the return sludge with a 20% loading percentage using 260 W electromagnetic waves for 45 seconds, the total amount of SCOD released from the system significantly increased. After loading, the SCOD concentrations in the return sludge supernatant and the nitrification solution supernatant increased by approximately 917.86% and 80%, respectively, compared to the unloaded system. This increased the organic loading of the A / A / O system by 2.073 kg COD / d and 0.225 kg COD / d, respectively. Based on the condition of loading the return sludge under condition II, after 75 seconds of irradiation treatment of the internal return nitrification liquid with a loading percentage of 10% by electromagnetic waves at condition III, the SCOD concentrations of the return sludge supernatant and the nitrification liquid supernatant increased by about 996.43% and 1051.43% respectively compared with the unloaded system, and the organic load of the A / A / O system increased by 2.251 kg COD / d and 2.969 kg COD / d respectively; compared with the system with only loading the return sludge, the SCOD concentrations of the return sludge supernatant and the nitrification liquid supernatant increased by 7.7% and 539.68% respectively, and the organic load of the A / A / O system increased by 0.177 kg COD / d and 2.743 kg COD / d respectively. This shows that the electromagnetic wave technology synergistically loading the internal and external return effectively promotes the release of organic matter in the return sludge and nitrification liquid. The results can be referred to Figure 2 .

[0100] Under different electromagnetic wave loading conditions, the positions and intensities of the specific characteristic peaks of the sludge samples before and after loading are shown in Table 2.

[0101] Table 2 Fluorescence spectrum parameters of sludge supernatant before and after electromagnetic wave loading

[0102]

[0103] Tryptophan-like substances, characteristic amino acids of proteins, are typically derived from the release of high-molecular-weight organic matter within cells and are highly biodegradable. During the anaerobic phase, these components are rapidly converted into small-molecule compounds such as volatile fatty acids (VFAs). These compounds are then reused as a supplemental carbon source by microorganisms in the denitrification unit, thus serving as indicators of the dynamics of organic carbon release in the system.

[0104] The experimental data in Table 2 show that when electromagnetic waves are loaded on the recirculated sludge, the peak intensities of the characteristic peaks of tryptophan-like substances in the EPS of the three activated sludges in the A / A / O system increase from 9494.5, 9450.8, and 9559.3 mV to 9854.7, 9854.7, and 9735.8 mV, an increase of 360.2, 403.9, and 176.5 mV. The increase in tryptophan-like substances is due to the loosening of the sludge floc structure and the rupture of microbial cells caused by electromagnetic wave loading, which leads to the release of extracellular polymeric substances (EPS) and intracellular components, thereby causing the accumulation of tryptophan-like substances in the liquid phase. Compared with the system without electromagnetic wave loading, the fluorescence intensity of tryptophan-like substances in the supernatant of the sludge samples in the anoxic tank and the aerobic tank caused by the coordinated loading of internal and external recirculation by electromagnetic waves increased by 5% and 3.81%, respectively. This shows that the coordinated loading of internal and external recirculation by electromagnetic waves effectively promotes the release of organic matter in the sludge. The results can be referred to Figure 3 .

[0105] Based on the results of Experiments 1 and 2, the optimal organic matter dissolution performance was achieved when the electromagnetic wave loading conditions were set at 260 W power, 45 s loading time, and 20% loading percentage for sludge loading, and 400 W power, 75 s loading time, and 10% loading percentage for internal nitrification solution loading. The mechanism of this effect can be summarized as follows: the addition of electromagnetic waves to the sludge and nitrification solution synergistically induces high-speed movement of polar molecules inside and outside the microbial cells in the sludge and nitrification solution, enhancing mechanical stress inside and outside the cell walls and promoting cell membrane rupture, thereby releasing intracellular degradable organic matter into the liquid phase. Fluorescence spectroscopy analysis revealed a significant increase in the fluorescence intensity of tryptophan-like substances and a significant increase in the SCOD concentration in the supernatant, demonstrating that the electromagnetic wave effect significantly promoted the release of organic matter from the sludge and nitrification solution. Through anaerobic conversion, these substances rapidly generate volatile organic acids, providing directly usable electron donors for subsequent denitrification.

[0106] Compared with existing technologies, this invention solves the problems of carbon source dependence, high operating costs, and secondary environmental pollution in existing sewage treatment technologies. Experiments have shown that the microwave-assisted electromagnetic wave loading of sludge return and nitrification solution return can expel organic matter from sludge and nitrification solution cells, significantly increasing the concentration of dissolved organic matter in the supernatant and the system's organic load, providing a green and low-carbon solution for the supply of carbon sources in sewage treatment plants.

[0107] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A carbon source supply system for a sewage treatment plant based on electromagnetic wave technology, characterized in that: include: An A / A / O reactor comprises an anaerobic tank (1), an anoxic tank (2) and an aerobic tank (3) which are connected in sequence; A water inlet pipe connected to the anaerobic tank (1); A secondary sedimentation tank (4) connected to the aerobic tank (3), wherein the secondary sedimentation tank (4) has a mud outlet; A first electromagnetic wave loading unit (5) having a first flow channel, wherein both ends of the first flow channel are connected to the water inlet pipeline and the mud outlet via a mud return pipe; and a second electromagnetic wave loading unit (6), which has a second flow channel, wherein both ends of the second flow channel are connected to the anoxic tank (2) and the aerobic tank (3) through nitrification liquid return pipes.

2. The carbon source supply system for sewage treatment plants based on electromagnetic wave technology according to claim 1, characterized in that: A stirrer is provided in the anaerobic tank (1).

3. The carbon source supply system for sewage treatment plants based on electromagnetic wave technology according to claim 1, characterized in that: A stirrer is provided in the anoxic tank (2).

4. The carbon source supply system for a sewage treatment plant based on electromagnetic wave technology according to claim 1, characterized in that: An aeration plate is provided in the aerobic tank (3), and the aeration plate is connected to an air pump.

5. The carbon source supply system for sewage treatment plants based on electromagnetic wave technology according to claim 1, characterized in that: A peristaltic pump is provided in communication between the first electromagnetic wave loading unit (5) and the water inlet pipeline.

6. The carbon source supply system for a sewage treatment plant based on electromagnetic wave technology according to claim 1, characterized in that: A peristaltic pump is provided in communication between the second electromagnetic wave loading unit (6) and the anoxic pool (2).

7. A method for supplying carbon sources to sewage treatment plants based on electromagnetic wave technology, characterized in that: The carbon source supply system for a sewage treatment plant based on electromagnetic wave technology according to any one of claims 1 to 6 comprises the following steps: 1) Use A / A / O reactor to treat sewage and operate stably for a period of time; 2) A portion of the sludge obtained from the secondary sedimentation tank is introduced into the anaerobic tank as return sludge. The return sludge is continuously excited by electromagnetic waves, thereby increasing the SCOD content of the supernatant of the return sludge output by the first electromagnetic wave loading unit and the SCOD content of the subsequent return nitrification liquid; 3) Part of the nitrification liquid from the aerobic tank is introduced into the anoxic tank as the return nitrification liquid, and the return nitrification liquid is continuously excited by electromagnetic waves to increase the SCOD content of the return nitrification liquid output by the second electromagnetic wave loading unit, and to increase the SCOD content of the supernatant of the return sludge output by the subsequent first electromagnetic wave loading unit.

8. The method for supplying carbon sources to sewage treatment plants based on electromagnetic wave technology according to claim 7, characterized in that: The power of continuous electromagnetic wave excitation for return sludge is 240-280 W; The continuous excitation time of electromagnetic waves on the return sludge is 40-50 s; Return sludge accounts for 15-25% of the total sludge; The frequency of continuous excitation of electromagnetic waves for return sludge is 2400-2500 MHz.

9. The method for supplying carbon sources to sewage treatment plants based on electromagnetic wave technology according to claim 7, characterized in that: The power of continuous electromagnetic wave excitation for the reflux nitrification solution is 360-440 W; The time of continuous excitation of electromagnetic waves on the reflux nitrification solution is 70-80 s; The reflux nitrification liquid accounts for 5-15% of the total nitrification liquid; The frequency of the continuous excitation of electromagnetic waves on the reflux nitrification liquid is 2400-2500 MHz.

10. The method for supplying carbon sources to sewage treatment plants based on electromagnetic wave technology according to claim 7, characterized in that: After the A / A / O reactor has been running stably for 25-35 days, continuous electromagnetic wave excitation is performed; Working temperature is 20-30 ℃; The dissolved oxygen in the aerobic tank is 1.60-1.70 mg / L; The sludge return ratio is 65-75%; The reflux ratio of nitrification liquid is 280-320%; The sludge retention time is 14-16 days.

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