In-situ recycling device and method for optimizing ultrasonic and alkali treatment of excess sludge

Abstract

The invention discloses an in-situ recycling device and method for optimizing ultrasonic and alkali treatment of excess sludge, belongs to the technical field of sewage sludge treatment, and solves the problems of high ultrasonic energy consumption, insufficient alkali utilization and lack of effective control on carbon source input in the sewage treatment process in the prior art. According to the invention, step-by-step adjustment of the pH is realized through the pH activation tank and the ultrasonic-alkali carbon source release tank, so that the sludge can operate under the optimal pH condition in each stage, and meanwhile, the low-energy-density ultrasonic is utilized to enhance the lysing capacity of alkali treatment, so that the treatment effect is improved, and the medicament utilization efficiency is optimized. Meanwhile, according to the scheme, the reflux ratio is adjusted in real time according to the actual COD concentration and TN concentration of the domestic sewage in combination with the ultrasonic energy density and pH value required in the ultrasonic-alkali carbon source release tank, so that the carbon-nitrogen ratio of the device is always in the optimal range, the condition of carbon source insufficiency or carbon source waste is avoided while the effluent quality is ensured to reach the standard, and the energy consumption of the device is reduced. Accurate and efficient operation of the device under low consumption is realized.

Description

Technical Field

[0001] The invention relates to the technical field of sewage sludge treatment, and in particular to a device and a method for optimizing in-situ resource utilization of excess sludge treated with ultrasound and alkali. Background Art

[0002] AO process is also called anoxic-aerobic process. A (Anoxic) is the anoxic stage, which is mainly used for denitrification and denitrification; O (Oxic) is the aerobic stage, which is used to achieve nitrification (ammonia nitrogen converted into nitrate) and remove organic matter in water. Its advantage is that in addition to degrading organic pollutants, it also has a certain denitrification function, and anoxic denitrification technology is used as the pretreatment of activated sludge.

[0003] In order to improve the nitrogen removal efficiency and reduce the problem of high carbon source consumption in the denitrification process, the existing technology often combines the AO process with ultrasonic technology, using ultrasonic waves to break the wall of the residual sludge, destroying the extracellular polymers (EPS) to release polysaccharides, proteins and a large amount of intracellular substances, but the ultrasonic energy consumption in the existing technology is relatively high.

[0004] In order to solve the above problems, the invention patent with announcement number CN117964186A discloses a method for cracking excess sludge, which enhances the release of organic matter in the cells of the excess sludge by increasing the cell permeability of the cells in the excess sludge and the mutual contact between the cells and the alkali, and can release the carbon source and achieve excess sludge reduction under mild reaction conditions, thereby reducing ultrasonic energy consumption. However, the cracking method uses a certain ultrasonic energy density and pH, and does not control the input of the carbon source according to the actual situation of the sewage, thereby failing to further optimize the ultrasonic energy density, the alkali consumption, and the optimal reflux ratio of the cracking liquid under the corresponding conditions. Summary of the invention

[0005] In view of the above problems in the prior art, the present invention provides a device and method for optimizing the in-situ resource utilization of residual sludge treated with ultrasound and alkali, which solves the problems of high ultrasonic energy consumption, insufficient alkali utilization and lack of effective control of carbon source input in the sewage treatment process in the prior art.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] On the one hand, a device for optimizing the in-situ resource utilization of residual sludge treated with ultrasound and alkali is provided, comprising: an AO system, the AO system comprising an anoxic tank, an aerobic tank and a sedimentation tank connected in sequence, the anoxic tank and the sedimentation tank being connected to a sewage inlet pipe and a sewage outlet pipe respectively; a pH activation tank, the pH activation tank being used to stimulate the microbial activity of the sludge, the pH activation tank being connected to the aerobic tank and the sedimentation tank respectively through a first return pipe and a sludge return pipe; an ultrasound-alkali carbon source release tank, the ultrasound-alkali carbon source release tank being used to improve the lysis ability of the sludge and release the carbon source, an ultrasonic device and a pH regulator being arranged in the ultrasound-alkali carbon source release tank, The water inlet of the ultrasonic-alkaline carbon source release pool is connected with the pH activation pool through a pipeline, and the water outlet of the ultrasonic-alkaline carbon source release pool is connected with the anoxic pool through a second return pipe; wherein, a TN detector and a COD detector are arranged in the sewage inlet pipe, the sewage outlet pipe and the second return pipe, and flow sensors are arranged in the sewage inlet pipe and the pipe; an electric flow valve for controlling the reflux ratio between the water inlet pipe and the second return pipe is arranged on the second return pipe; the ultrasonic device, the pH regulator, all the TN detectors, all the COD detectors, all the flow sensors, the electric flow valve and all the flow sensors are electrically connected to the upper computer.

[0008] In this scheme, both the pH activation tank and the ultrasound-alkaline carbon source release tank are alkaline environments. By adjusting the pH value in steps, each stage can operate under the optimal pH conditions, which not only improves the treatment effect but also reduces excessive resource consumption. Specifically, the pH activation tank maintains a relatively low but effective alkaline level. It can not only stimulate microbial activity through a relatively mild alkaline environment, promote the release of extracellular polymers (EPS), increase the utilization capacity of dissolved oxygen and ensure the nitrification removal effect of ammonia nitrogen, and facilitate subsequent treatment, but also avoid the negative impact of excessively increasing pH on microbial activity, ensure that the microbial community in the sludge is in the best state of activity, and reduce the alkali consumption required for the relatively high pH environment in the ultrasound-alkaline carbon source release tank. At the same time, this scheme takes into account that the domestic sewage discharged from the sewage inlet pipe is flowing, and the COD concentration and TN concentration in the domestic sewage are a fluctuating process, which will affect the actual carbon source demand. Therefore, the ultrasonic energy density and pH value required in the ultrasonic-alkali carbon source release tank can be adjusted in real time according to the actual COD concentration and TN concentration of domestic sewage. The required ultrasonic-alkali treated sludge return ratio can be calculated online by the host computer, and the flow rate can be automatically adjusted by the electric flow valve to achieve the return ratio, ensuring that the carbon-nitrogen ratio of the device is always in the optimal range. Therefore, this scheme uses COD detectors and TN detectors to monitor the COD concentration and TN concentration of each location online, and adjusts the ultrasonic energy density and pH value of the ultrasonic-alkali carbon source release tank in real time through the host computer. In summary, this scheme can reduce ultrasonic energy consumption and alkali drug consumption while ensuring that the effluent quality meets the standard, avoid insufficient or wasteful carbon sources, and achieve accurate and efficient automatic control of the system.

[0009] Furthermore, the aerobic pool is connected to the anoxic pool through the third return pipe. At the same time, the third return pipe realizes the return of the aerobic pool to the anoxic pool, also known as the nitrification liquid return. In the aerobic pool, ammonia nitrogen is converted into nitrate by the action of nitrifying bacteria. When these nitrified liquids are returned to the anoxic pool, they provide the necessary nitrate nitrogen source for the denitrification process. Under anaerobic conditions, denitrifying bacteria can use nitrate as an electron acceptor to reduce nitrate to nitrogen gas and release it into the atmosphere, thereby removing total nitrogen from sewage.

[0010] Furthermore, the pH value in the pH activation tank is 9 to 10. The relatively mild alkaline environment can stimulate microbial activity and promote the release of extracellular polymers (EPS), while avoiding the negative impact of excessively increasing pH on microbial activity. Since the pH of the ultrasound-alkali carbon source release tank is regulated in real time based on the host computer, the required alkali consumption can be used more accurately, so the pH activation tank reduces the amount of alkali required to directly enter the high pH environment in the ultrasound-alkali carbon source release tank.

[0011] Furthermore, the ultrasonic energy density and pH in the ultrasonic-alkali carbon source release cell are 0-0.3 W / mL and 11-12.5, respectively. The ultrasonic energy density is used to assist the lysing effect of the alkali, reduce the energy consumption of traditional ultrasound, minimize the energy consumption of ultrasound and the amount of alkali used while ensuring the treatment effect, and further reduce the operating cost.

[0012] Furthermore, an agitator is provided in the anoxic tank. The function of the agitator is to keep the sludge in suspension, so that the sludge and wastewater are fully mixed and contacted, improve the mass transfer efficiency, and facilitate the biological reaction process. At the same time, it can also prevent the sludge from settling and ensure the treatment effect.

[0013] Furthermore, the sedimentation tank and the anoxic tank are arranged to be reflux-connected.

[0014] On the other hand, a method for optimizing an in-situ resource recovery device for treating excess sludge with ultrasound and alkali is provided, comprising the steps of:

[0015] S1. Using an anoxic tank and an aerobic tank in turn to treat sewage from a sewage inlet pipe to obtain a first mixed solution.

[0016] S2. Return a portion of the first mixed liquor to the anoxic tank, and the remaining portion of the first mixed liquor flows into the sedimentation tank for sedimentation treatment to obtain a second mixed liquor and a first sludge, and the second mixed liquor is discharged through a sewage outlet pipe.

[0017] S3. Discharge a portion of the first sludge, and input the remaining portion into a pH activation tank through a sludge return pipe; use the pH activation tank to stimulate and enhance the microbial activity in the first sludge and secrete extracellular polymers to obtain a second sludge, return a portion of the second sludge to the aerobic tank, and transport the remaining portion of the second sludge to an ultrasound-alkali carbon source release tank through a pipeline.

[0018] S4, according to the sludge load N of the entire device s Limiting relationship to adjust ultrasonic energy density and pH value in ultrasonic-alkali carbon source release tank, sludge load N S The restriction relation is:

[0019]

[0020] in:

[0021] S COD =406.992+57.640log(x)+184.799exp(-9.69×10 10 y)-476.351x 2 +y 2 -4.392×10 10 ·xy

[0022] S TN =44.642+1.437log(x)+57.736exp(-2.71×10 10 y)-28.929x 2 +y 2 +xy

[0023] Among them, N s is the sludge load, in kgMLSS·d; Q is the inlet flow rate of the sewage inlet pipe, in m 3 / d; X is the concentration of suspended solids in the mixed solution in the anoxic tank and the aerobic tank, and 2.0≤X≦4.0, in g / L; V is the total volume of the anoxic tank and the aerobic tank, in m 3 ; S COD and S TN are the COD concentration and TN concentration in the ultrasound-alkali carbon source release pool, both in mg / L; S in-COD is the COD concentration in the sewage inlet pipe, in mg / L; S en-COD is the COD concentration in the sewage outlet pipe, in mg / L; x is the ultrasonic energy density, in W / mL; y is H + Concentration, used to reflect pH value, the unit is mol / L.

[0024] In step S4, the sludge load N sIt refers to the amount of organic pollutants that can be accepted and degraded to a predetermined degree by the unit mass of activated sludge in the reaction tank within a unit time. In this scheme, the entire device can achieve the effluent water quality index in the sludge load of 0.2-0.4. At the same time, the sludge load constrains the COD concentration and TN concentration in the ultrasonic-alkali carbon source release tank, so according to S COD and S TN The fitting formula can be used to calculate the ultrasonic energy density and H + The minimum concentration reduces unnecessary waste while meeting the effluent water quality indicators.

[0025] S5, using ultrasound-alkali carbon source release tank to improve the lysis ability of the second sludge microorganisms and release carbon source, to obtain cracking liquid, and through the electric flow valve according to the reflux ratio R between the water inlet pipe and the second reflux pipe 1 The cracking liquid is returned to the anoxic tank, and the return ratio R 1 for:

[0026]

[0027] Among them, S in-TN It is the TN concentration in the sewage inlet pipe, in mg / L.

[0028] In step S5, the ultrasound-alkali carbon source release tank causes the second sludge to release additional carbon source (COD), which can serve as electron donors required for the denitrification process in the anoxic tank. 1 , the amount of carbon source entering the anoxic tank can be controlled to ensure that the carbon-nitrogen ratio of the device is always in the optimal range, thereby improving the efficiency and stability of the device.

[0029] Furthermore, S in-COD 150~600mg / L; S in-TN The concentration of suspended solids in the mixed solution of the pH activation tank and the ultrasound-alkali carbon source release tank is 30-80 mg / L, and the concentration of suspended solids in the mixed solution of the pH activation tank and the ultrasound-alkali carbon source release tank is 12.0-15.0 g / L. These limiting conditions help maintain the stable operation of the device, ensure that the effluent water quality meets the standards, and further optimize resource utilization.

[0030] Furthermore, the return flow rate of the first mixed liquid to the anoxic tank is 300% of the inlet flow rate of the sewage inlet pipe. When the nitrified liquid in the aerobic tank is returned to the anoxic tank through the high return ratio set in this way, sufficient nitrate nitrogen source is provided for the denitrification process, thereby improving the denitrification efficiency.

[0031] Furthermore, the ratio of the first sludge returned from the sedimentation tank to the anoxic tank is R 2 , where R 2 =1-R 1 . Set R 2, which makes it easy to control the sludge concentration in the anoxic tank and the aerobic tank to remain stable at all times.

[0032] The present invention discloses a device and method for optimizing the in-situ resource utilization of excess sludge treated with ultrasound and alkali, and the beneficial effects are as follows:

[0033] The present invention realizes the step-by-step adjustment of pH through the pH activation tank and the ultrasonic-alkali carbon source release tank, so that the sludge can operate under the optimal pH conditions at each stage, which not only improves the treatment effect but also reduces resource consumption. At the same time, this scheme adjusts the corresponding ultrasonic energy density and pH value in the ultrasonic-alkali carbon source release tank in real time according to the actual COD concentration and TN concentration of domestic sewage, and ensures that the carbon-nitrogen ratio of the device is always in the optimal range by adjusting the reflux ratio in real time. Therefore, the present invention reduces the ultrasonic energy consumption and alkali drug consumption while ensuring that the effluent water quality meets the standard, avoids the situation of insufficient or waste of carbon source, and realizes the precise and efficient operation of the device under low consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of the structure of a device for optimizing the in-situ resource utilization of excess sludge treated with ultrasound and alkali;

[0035] Among them: 1. Anoxic tank; 2. Aerobic tank; 3. Sedimentation tank; 4. pH activation tank; 5. Ultrasonic-alkali carbon source release tank; 6. Electric flow valve; 7. Sewage inlet pipe; 8. Sewage outlet pipe; 11. First return pipe; 12. Second return pipe; 13. Third return pipe. DETAILED DESCRIPTION

[0036] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0037] Example 1

[0038] refer to Figure 1 , which is a schematic diagram of the structure of the device and method for optimizing the in-situ resource utilization of residual sludge treated with ultrasound and alkali, and its purpose is to solve the problem of high ultrasonic energy consumption and high alkali consumption in the sewage treatment process in the prior art. It will be shown in detail below.

[0039] A device for optimizing the in-situ resource utilization of excess sludge treated with ultrasound and alkali comprises: an AO system, a pH activation tank 4 and an ultrasound-alkali carbon source release tank 5.

[0040] The AO system includes an anoxic tank 1, an aerobic tank 2 and a sedimentation tank 3 which are connected in sequence, and the sedimentation tank 3 is connected to the anoxic tank 1 in a reflux manner. The anoxic tank 1 and the sedimentation tank 3 are connected to the sewage inlet pipe 7 and the sewage outlet pipe 8 respectively. The aerobic tank 2 is connected to the anoxic tank 1 through a third reflux pipe 13. An agitator is provided in the anoxic tank 1.

[0041] The pH activation tank 4 is used to stimulate the microbial activity of the sludge. The pH activation tank 4 is connected to the aerobic tank 2 and the sedimentation tank 3 through the first return pipe 11 and the sludge return pipe respectively.

[0042] In this embodiment, the pH value in the pH activation tank 4 is 9-10. The pH activation tank 4 maintains a relatively low but effective alkaline level, which can not only stimulate microbial activity through a relatively mild alkaline environment, promote the release of extracellular polymers (EPS), increase the dissolved oxygen utilization capacity and ensure the ammonia nitrogen nitrification removal effect, and facilitate subsequent treatment, but also avoid the negative impact of excessively increasing pH on microbial activity, ensure that the microbial community in the sludge is in the best activity state, and can reduce the alkali consumption required for the relatively high pH environment in the ultrasound-alkaline carbon source release tank 5.

[0043] The ultrasonic-alkali carbon source release tank 5 is used to improve the lysis ability of the sludge and release the carbon source. An ultrasonic device and a pH regulator are arranged in the ultrasonic-alkali carbon source release tank 5. The water inlet of the ultrasonic-alkali carbon source release tank 5 is connected to the pH activation tank 4 through a pipeline, and the water outlet of the ultrasonic-alkali carbon source release tank 5 is connected to the anoxic tank 1 through a second reflux pipe 12. Preferably, the ultrasonic energy density and pH in the ultrasonic-alkali carbon source release tank 5 are 0-0.3 W / mL and 11-12.5, respectively.

[0044] Among them, TN detectors and COD detectors are provided in the sewage inlet pipe 7, the sewage outlet pipe 8 and the second return pipe 12, and flow sensors are provided in the sewage inlet pipe 7 and the pipe; an electric flow valve 6 for controlling the reflux ratio between the inlet pipe and the second return pipe 12 is provided on the second return pipe 12; the ultrasonic device, pH regulator, all TN detectors, all COD detectors, all flow sensors, the electric flow valve 6 and all flow sensors are electrically connected to the host computer.

[0045] This scheme optimizes the consumption and utilization of ultrasonic energy density and pH through process design, and also takes into account that the domestic sewage discharged from the sewage inlet pipe 7 is flowing, and the COD concentration and TN concentration in the domestic sewage are a fluctuating process, so that the corresponding ultrasonic energy density and pH value in the ultrasonic-alkaline carbon source release tank 5 can be adjusted in real time according to the actual COD concentration and TN concentration of the domestic sewage to achieve minimum consumption. Therefore, this scheme uses a COD detector and a TN detector to monitor the COD concentration and TN concentration of each location online, and adjusts the ultrasonic energy density and pH value of the ultrasonic-alkaline carbon source release tank 5 in real time through the host computer. At the same time, the host computer calculates the required ultrasonic-alkali treatment sludge return ratio online, and automatically adjusts the flow rate through the electric flow valve 6 to achieve the return ratio, ensuring that the carbon-nitrogen ratio of the device is always in the optimal range.

[0046] Example 2

[0047] This embodiment is further limited on the basis of Embodiment 1. The specific improvement lies in how to treat sewage based on an apparatus for in-situ resource utilization of residual sludge by optimizing ultrasound and alkali treatment. For other parts not mentioned, refer to Embodiment 1 or the prior art.

[0048] This embodiment provides a method for optimizing an in-situ resource recovery device for residual sludge treated with ultrasound and alkali, comprising the steps of:

[0049] S1. The anoxic tank 1 and the aerobic tank 2 are used in sequence to treat the sewage in the sewage inlet pipe 7 to obtain a first mixed solution.

[0050] S2. Return a portion of the first mixed liquor to the anoxic tank 1, and the remaining portion of the first mixed liquor flows into the sedimentation tank 3 for sedimentation treatment to obtain a second mixed liquor and a first sludge, and the second mixed liquor is discharged through the sewage outlet pipe 8.

[0051] Preferably, the return flow rate of the first mixed liquid returning to the anoxic tank 1 is 300% of the inlet flow rate of the sewage inlet pipe.

[0052] S3. A portion of the first sludge is discharged, and the remaining portion is input into the pH activation tank 4 through the sludge return pipe; the pH activation tank 4 is used to stimulate and enhance the microbial activity in the first sludge and secrete extracellular polymers to obtain a second sludge, and a portion of the second sludge is returned to the aerobic tank 2, and the remaining portion of the second sludge is transported to the ultrasound-alkali carbon source release tank 5 through a pipeline.

[0053] S4, according to the sludge load N of the entire device s The limiting relationship is used to adjust the ultrasonic energy density and pH value in the ultrasonic-alkali carbon source release tank 5, and the sludge load N s The restriction relation is:

[0054]

[0055] in:

[0056] S COD =406.992+57.640log(x)+184.799exp(-9.69×10 10 y)-476.351x 2 +y 2 -4.392×10 10 ·xy

[0057] S TN =44.642+1.437log(x)+57.736exp(-2.71×10 10 y)-28.929x 2 +y 2 +xy

[0058] Among them, N S is the sludge load, in kgMLSS·d; Q is the inlet flow rate of the sewage inlet pipe 7, in m 3 / d; X is the suspended solid concentration of the mixed liquor in the anoxic pool 1 and the aerobic pool 2, and 2.0≤X≦4.0, in g / L; V is the total volume of the anoxic pool 1 and the aerobic pool 2, in m 3 ; S COD and S TN are the COD concentration and TN concentration in ultrasound-alkali carbon source release pool 5, both in mg / L; S in-COD is the COD concentration in the sewage inlet pipe 7, in mg / L; S en-COD is the COD concentration in the sewage outlet pipe 8, in mg / L; x is the ultrasonic energy density, in W / mL; y is H + Concentration, used to reflect pH value, the unit is mol / L.

[0059] In step S4, the sludge load N s It refers to the amount of organic pollutants that can be accepted and degraded to a predetermined degree by the unit mass of activated sludge in the reaction tank within a unit time. In this scheme, the entire device can achieve the effluent water quality index in the sludge load of 0.2-0.4. At the same time, the sludge load constrains the COD concentration and TN concentration in the ultrasonic-alkali carbon source release tank 5, so according to S COD and S TN The fitting formula can be used to calculate the ultrasonic energy density and H in the ultrasonic-alkali carbon source release cell 5. + The minimum or smaller value of the concentration can reduce unnecessary waste while meeting the effluent water quality indicators.

[0060] S5, using the ultrasound-alkali carbon source release tank 5 to improve the lysis ability of the second sludge microorganisms and release the carbon source, to obtain the cracking liquid, and through the electric flow valve 6 according to the reflux ratio R between the water inlet pipe and the second reflux pipe 12 1 The cracked liquid is returned to the anoxic tank 1, and the return ratio R 1 for:

[0061]

[0062] Among them, S in-TN is the TN concentration in the sewage inlet pipe 7, in mg / L.

[0063] As a further solution of this embodiment, the ratio of the first sludge returned from the sedimentation tank to the anoxic tank is R 2 , where R 2 =1-R 1 . Set R 2 , which makes it easy to control the sludge concentration in the anoxic tank and the aerobic tank to remain stable at all times.

[0064] In step S5, the ultrasonic-alkali carbon source release tank 5 causes the second sludge to release additional carbon source (COD), which can serve as electron donors required for the denitrification process in the anoxic tank 1. By adjusting the reflux ratio R in real time 1 , the amount of carbon source entering the anoxic pool 1 can be controlled to ensure that the carbon-nitrogen ratio of the device is always within the optimal range, thereby improving the efficiency and stability of the device.

[0065] Preferably, S in-COD 150~600mg / L; S in-TN The concentration of suspended solids in the mixed solution of the pH activation tank 4 and the ultrasound-alkali carbon source release tank 5 is 30-80 mg / L, and the concentration of suspended solids in the mixed solution of the pH activation tank 4 and the ultrasound-alkali carbon source release tank 5 is 12.0-15.0 g / L. These limiting conditions help to maintain the stable operation of the device, ensure that the effluent water quality meets the standards, and further optimize the resource utilization.

[0066] Although the specific implementation of the invention is described in detail in conjunction with the drawings, it should not be understood as limiting the scope of protection of this patent. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A device for optimizing the in-situ resource utilization of excess sludge treated with ultrasound and alkali, characterized in that: include: An AO system, the AO system comprising an anoxic tank (1), an aerobic tank (2) and a sedimentation tank (3) which are connected in sequence, the anoxic tank (1) and the sedimentation tank (3) being connected to a sewage inlet pipe (7) and a sewage outlet pipe (8) respectively; A pH activation tank (4), wherein the pH activation tank (4) is used to stimulate the microbial activity of the sludge, and the pH activation tank (4) is connected to the aerobic tank (2) and the sedimentation tank (3) through a first return pipe (11) and a sludge return pipe respectively; An ultrasonic-alkaline carbon source release tank (5), the ultrasonic-alkaline carbon source release tank (5) is used to improve the lysis ability of sludge and release the carbon source, an ultrasonic device and a pH regulator are arranged in the ultrasonic-alkaline carbon source release tank (5), the water inlet of the ultrasonic-alkaline carbon source release tank (5) is connected to the pH activation tank (4) through a pipeline, and the water outlet of the ultrasonic-alkaline carbon source release tank (5) is connected to the anoxic tank (1) through a second reflux pipe (12); The sewage inlet pipe (7), the sewage outlet pipe (8) and the second return pipe (12) are all provided with a TN detector and a COD detector, and the sewage inlet pipe (7) and the pipe are both provided with flow sensors; the second return pipe (12) is provided with an electric flow valve (6) for controlling the return ratio between the inlet pipe and the second return pipe (12); The ultrasonic device, the pH regulator, all TN detectors, all COD detectors, all flow sensors, the electric flow valve (6) and all flow sensors are electrically connected to a host computer.

2. The device according to claim 1, characterized in that The aerobic pool (2) is connected to the anoxic pool (1) via a third reflux pipe (13).

3. The device according to claim 1, characterized in that The pH value set in the pH activation tank (4) is 9-10.

4. The device according to claim 1, characterized in that The ultrasonic energy density and pH in the ultrasonic-alkali carbon source release cell (5) are 0-0.3 W / mL and 11-12.5 respectively.

5. The device according to claim 1, characterized in that A stirrer is arranged in the anoxic tank (1).

6. The device according to claim 1, characterized in that The sedimentation tank (3) and the anoxic tank (1) are arranged in reflux communication.

7. The method for optimizing the in-situ resource utilization of the device for ultrasonic and alkali treatment of excess sludge according to any one of claims 1 to 6, characterized in that: Includes steps: S1, using the anoxic tank (1) and the aerobic tank (2) in sequence to treat the sewage from the sewage inlet pipe (7) to obtain a first mixed liquid; S2, returning a portion of the first mixed liquid to the anoxic tank (1), and the remaining portion of the first mixed liquid flows into the sedimentation tank (3) for sedimentation treatment to obtain a second mixed liquid and a first sludge, and the second mixed liquid is discharged through a sewage outlet pipe (8); S3, discharging a portion of the first sludge, and inputting the remaining portion into the pH activation tank (4) through the sludge return pipe; A pH activation tank (4) is used to stimulate and enhance the microbial activity in the first sludge and secrete extracellular polymers to obtain a second sludge, a portion of the second sludge is returned to the aerobic tank (2), and the remaining portion of the second sludge is transported to the ultrasound-alkali carbon source release tank (5) through a pipeline; S4, according to the sludge load N of the entire device s The limiting relationship is used to adjust the ultrasonic energy density and pH value in the ultrasonic-alkali carbon source release tank (5), and the sludge load N s The restriction relation is: in: S COD =406.992+57.640log(x)+184.799exp(-9.69×10 10 ·y)-476.351x 2 +y 2 -4.392×10 10 ·xy S TN =44.642+1.437log(x)+57.736exp(-2.71×10 10 ·y)-28.929x 2 +y 2 +xy Among them, N s is the sludge load, in kgMLSS·d; Q is the inlet flow rate of the sewage inlet pipe (7), in m 3 / d; X is the concentration of suspended solids in the mixed liquor in the anoxic tank (1) and the aerobic tank (2), and 2.0≤X≦4.0, in g / L; V is the total volume of the anoxic tank (1) and the aerobic tank (2), in m 3 ; S COD and S TN are the COD concentration and TN concentration in the ultrasound-alkaline carbon source release pool (5), both in mg / L; S in-COD is the COD concentration in the sewage inlet pipe (7), in mg / L; S en-COD is the COD concentration in the sewage outlet pipe (8), in mg / L; x is the ultrasonic energy density, in W / mL; y is H + Concentration, used to reflect pH value, unit is mol / L; S5. The ultrasonic-alkali carbon source release tank (5) is used to improve the lysis ability of the second sludge microorganism and release the carbon source to obtain a cracking liquid, and the cracking liquid is returned to the anoxic tank (1) through the electric flow valve (6) according to the reflux ratio R1 between the water inlet pipe and the second reflux pipe (12). The reflux ratio R1 is: Among them, S in-TN is the TN concentration in the sewage inlet pipe (7), in mg / L.

8. The method according to claim 7, characterized in that S in-COD 150~600mg / L; S in-TN The suspended solid concentration of the mixed solution in the pH activation tank (4) and the ultrasound-alkali carbon source release tank (5) is 30-80 mg / L, and the suspended solid concentration of the mixed solution in the pH activation tank (4) and the ultrasound-alkali carbon source release tank (5) is 12.0-15.0 g / L.

9. The method according to claim 7, characterized in that: The return flow rate of the first mixed liquid returning to the anoxic tank (1) is 300% of the inlet flow rate of the sewage inlet pipe (7).

10. The method according to claim 7, characterized in that The ratio of the first sludge returned from the sedimentation tank (3) to the anoxic tank (1) is R2, wherein R2 = 1-R1.

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