Bacteria-algae symbiotic device suitable for treating rural sewage through photovoltaic intermittent energy supply

Abstract

A bacteria-algae symbiotic device suitable for treating rural sewage by photovoltaic intermittent energy supply belongs to the technical field of sewage treatment, and comprises a main reactor, a lighting system, an aeration system, a photovoltaic power generation system, an energy storage system, a stirring system, a water inlet system and a drainage system, the main reactor adopts a vertical transparent tank body structure, and the bottom of the tank body is connected with the aeration system; the lighting system is arranged on the outer surface of the main reactor tank body; the photovoltaic power generation system is used as a main power supply of the illumination system, the aeration system, the stirring system, the water inlet system and the drainage system, and the photovoltaic power generation system is used as a charging power supply of the energy storage system; the energy storage system serves as a supplementary power supply of the lighting system; the stirring system is arranged in the main reactor tank body; the water inlet system is connected with a tank body water inlet of the main reactor; the drainage system is connected with a tank body drainage port of the main reactor; and the main reactor is provided with an online monitoring system. The device has the characteristics of simple structure, low sewage treatment cost and low facility operation and maintenance cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and particularly relates to a bacteria-algae symbiotic device suitable for treating rural sewage with photovoltaic intermittent power supply. Background Art

[0002] In recent years, with the development of clean energy technologies and the implementation of carbon emission reduction work, using clean energies such as photovoltaic as supplementary energy for the operation of sewage treatment facilities has become a development trend.

[0003] The Chinese patent application with the publication number CN112094003A discloses an integrated solar sewage treatment device and a method for treating sewage. This solution uses anaerobic-anoxic-aerobic-sedimentation as the treatment process, combines solar energy with a graphene battery as the main power supply method, and uses municipal electricity as the auxiliary power supply method. However, this solution still needs to add a battery for energy storage to ensure the power consumption requirements of high-power equipment such as aeration and stirring, and thus ensure the continuous and stable operation of the sewage treatment device. It fails to implement sewage treatment based on the intermittent power supply law of photovoltaic facilities, and the power consumption of the municipal electricity auxiliary power supply is still relatively high.

[0004] The Chinese patent application with the publication number CN115304169A discloses a bacteria-algae symbiotic system and a method and device for treating domestic sewage. This solution is based on the bacteria-algae symbiotic technology and has a good ability to remove nitrogen and phosphorus from domestic sewage. However, the energy consumption of the photobioreactor in this solution does not mention clean energies such as photovoltaic. In order to ensure a high aeration volume and sufficient hydraulic shear force in the photobioreactor, high energy consumption is required for aeration and stirring. Assuming that clean energies such as photovoltaic are introduced, due to the intermittent power supply law of photovoltaic facilities, its photobioreactor cannot adapt to intermittent power supply, and thus cannot achieve stable sewage treatment under intermittent power supply conditions. Summary of the Invention

[0005] Aiming at the problems existing in the prior art, the present invention provides a bacteria-algae symbiotic device suitable for treating rural sewage with photovoltaic intermittent power supply. It is designed based on the intermittent power supply law of photovoltaic facilities, uses photovoltaic power generation as the main power supply method, and only uses energy storage power supply as the supplementary power supply method for the lighting system, greatly reducing the energy storage power supply demand. It has the characteristics of simple structure, low sewage treatment cost, and low facility operation and maintenance cost, can better adapt to intermittent power supply conditions, and can achieve stable sewage treatment under intermittent power supply conditions.

[0006] To achieve the above object, the present invention adopts the following technical solution: A symbiotic bacteria-algae device suitable for photovoltaic intermittent energy supply to treat rural sewage, comprising a main reactor, a lighting system, an aeration system, a photovoltaic power generation system, an energy storage system, a stirring system, a water inlet system and a drainage system; the main reactor adopts a vertical transparent tank structure, and the bottom of the tank body of the main reactor is connected to the aeration system; the lighting system is arranged on the outer surface of the tank body of the main reactor; the photovoltaic power generation system serves as the main power supply for the lighting system, the aeration system, the stirring system, the water inlet system and the drainage system, and the photovoltaic power generation system serves as the charging power supply for the energy storage system; the energy storage system serves as the supplementary power supply for the lighting system; the stirring system is arranged inside the tank body of the main reactor; the water inlet system is connected to the water inlet of the tank body of the main reactor; the drainage system is connected to the water outlet of the tank body of the main reactor.

[0007] The operation time of the main reactor is 6h to 8h, and the shutdown time of the main reactor is 16h to 18h; during the operation stage of the main reactor, the water inlet duration of the water inlet system is 5min to 10min, the anoxic stirring duration of the stirring system is 2h to 3h, the aerobic aeration duration of the aeration system is 3h to 6h, the sedimentation duration after aeration is 25min to 30min, and the drainage duration of the drainage system is 5min to 10min.

[0008] Polyurethane soft fillers are filled inside the tank body of the main reactor. The particle shape of the polyurethane soft fillers is a cube with a side length of 20mm to 40mm. The filling amount of the polyurethane soft fillers is 10% to 30% of the volume of the tank body of the main reactor, and the total surface area of the polyurethane soft fillers is not less than 6000m per cubic meter 2 .

[0009] The lighting system includes an LED light strip, which is wound and fixed on the outer surface of the tank body of the main reactor in a spiral manner. The protection level of the LED light strip is not less than IP65, and the average light intensity applied by the LED light strip to the inside of the tank body of the main reactor is 3500Lux to 6000Lux.

[0010] During the operation of the main reactor, the lighting duration applied by the LED light strip to the inside of the tank body of the main reactor is 8h to 12h, and the light-dark cycle ratio inside the tank body of the main reactor is (8 - 12):(12 - 16).

[0011] The aeration system includes an air pump, an aeration pipe, and an aeration head. The aeration head is located at the inner bottom end of the main reactor tank body. The air pump is located outside the main reactor tank body. One end of the aeration pipe is connected to the air pump, and the other end of the aeration pipe seals through the main reactor tank body and is connected to the aeration head. The aeration system adopts an intermittent operation mode. During the operation stage of the aeration system, the dissolved oxygen concentration of the sewage inside the main reactor tank body is maintained at 1 mg / L to 5 mg / L.

[0012] The stirring system includes a stirring motor, a stirring shaft, and stirring blades. The stirring motor is installed at the outer top end of the main reactor tank body. The stirring shaft is located at the inner center of the main reactor tank body. The upper end of the stirring shaft is coaxially connected to the motor shaft of the stirring motor. The stirring blades are arranged at the bottom end of the stirring shaft. The stirring system adopts an intermittent operation mode. During the operation stage of the stirring system, the stirring speed of the stirring blades is maintained at 80 rpm to 200 rpm.

[0013] The water inlet system includes a raw water tank, a water inlet pump, and a water inlet flow meter. The water outlet of the raw water tank is connected to the water inlet of the water inlet pump. The water outlet of the water inlet pump is connected to the water inlet of the main reactor tank body. The water inlet of the tank body is located at the upper end of the main reactor tank body. The water inlet flow meter is arranged on the water inlet pipeline between the water outlet of the water inlet pump and the water inlet of the main reactor tank body. The water inlet system adopts an intermittent operation mode. During the operation stage of the water inlet system, the total water inflow inside the main reactor tank body is maintained at 20% to 40% of the effective volume of the main reactor tank body.

[0014] The drainage system includes a drainage pump and a drainage flow meter. The water inlet of the drainage pump is connected to the drainage outlet of the main reactor tank body. The drainage outlet of the tank body is located in the middle of the main reactor tank body. The drainage flow meter is arranged on the drainage pipeline between the water inlet of the drainage pump and the drainage outlet of the main reactor tank body. The drainage system adopts an intermittent operation mode.

[0015] The main reactor is equipped with an online monitoring system. The online monitoring system includes a computer, a dissolved oxygen concentration meter, a sludge concentration meter, and a light intensity meter. The operations of the lighting system, the aeration system, the photovoltaic power generation system, the energy storage system, the stirring system, the water inlet system, and the drainage system are all uniformly controlled by the computer. The dissolved oxygen concentration in the sewage is detected in real time through the dissolved oxygen concentration meter. The sludge concentration in the sewage is monitored in real time through the sludge concentration meter. The light intensity of the lighting system is monitored in real time through the light intensity meter.

[0016] Advantages of the present invention: The algal-bacterial symbiotic device for treating rural sewage applicable to photovoltaic intermittent power supply of the present invention is designed based on the intermittent power supply law of photovoltaic facilities. Taking photovoltaic power generation as the main power supply method and only using energy storage power supply as the supplementary power supply method for the lighting system, the energy storage power supply demand is greatly reduced. It has the characteristics of simple structure, low sewage treatment cost and low facility operation and maintenance cost, can better adapt to intermittent power supply conditions, and can achieve stable sewage treatment under intermittent power supply conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of an algal-bacterial symbiotic device for treating rural sewage applicable to photovoltaic intermittent power supply of the present invention; In the figure, 1 - main reactor, 2 - lighting system, 3 - aeration system, 4 - photovoltaic power generation system, 5 - energy storage system, 6 - stirring system, 7 - water inlet system, 8 - drainage system, 9 - polyurethane soft filler, 10 - air pump, 11 - air pipe, 12 - aeration head, 13 - stirring motor, 14 - stirring shaft, 15 - stirring paddle, 16 - raw water tank, 17 - water inlet pump, 18 - water inlet flowmeter, 19 - drainage pump, 20 - drainage flowmeter. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0019] As Figure 1 shown, an algal-bacterial symbiotic device for treating rural sewage applicable to photovoltaic intermittent power supply includes a main reactor 1, a lighting system 2, an aeration system 3, a photovoltaic power generation system 4, an energy storage system 5, a stirring system 6, a water inlet system 7 and a drainage system 8; the main reactor 1 adopts a vertical transparent tank structure, and the bottom of the tank of the main reactor 1 is connected to the aeration system 3; the lighting system 2 is arranged on the outer surface of the tank of the main reactor 1; the photovoltaic power generation system 4 serves as the main power supply for the lighting system 2, the aeration system 3, the stirring system 6, the water inlet system 7 and the drainage system 8, and the photovoltaic power generation system 4 serves as the charging power supply for the energy storage system 5; the energy storage system 5 serves as the supplementary power supply for the lighting system 2; the stirring system 6 is arranged inside the tank of the main reactor 1; the water inlet system 7 is connected to the water inlet of the tank of the main reactor 1; the drainage system 8 is connected to the water outlet of the tank of the main reactor 1.

[0020] The operation time of the main reactor 1 is 6h - 8h, and the shutdown time of the main reactor 1 is 16h - 18h; during the operation stage of the main reactor 1, the water inlet duration of the water inlet system 7 is 5min - 10min, the anoxic stirring duration of the stirring system 6 is 2h - 3h, the aerobic aeration duration of the aeration system 3 is 3h - 6h, the precipitation duration after aeration is 25min - 30min, and the drainage duration of the drainage system 8 is 5min - 10min.

[0021] Inside the tank body of the main reactor 1, polyurethane soft fillers 9 are filled. The particle shape of the polyurethane soft fillers 9 is a cube, and the side length of the cube is 20 mm to 40 mm. The filling amount of the polyurethane soft fillers 9 is 10% to 30% of the volume of the tank body of the main reactor 1, and the total surface area of the polyurethane soft fillers 9 is not less than 6000 m per cubic meter 2 .

[0022] The lighting system 2 includes an LED light strip, which is wound and fixed on the outer surface of the tank body of the main reactor 1 in a spiral manner. The protection level of the LED light strip is not less than IP65, and the average light intensity applied by the LED light strip to the inside of the tank body of the main reactor 1 is 3500 Lux to 6000 Lux.

[0023] During the operation of the main reactor 1, the lighting duration of the inside of the tank body of the main reactor 1 applied by the LED light strip is 8 h to 12 h, and the light-dark cycle ratio inside the tank body of the main reactor 1 is (8 - 12):(12 - 16).

[0024] The aeration system 3 includes an air pump 10, an aeration pipe 11 and an aeration head 12. The aeration head 12 is located at the inner bottom end of the tank body of the main reactor 1. The air pump 10 is located outside the tank body of the main reactor 1. One end of the aeration pipe 11 is connected to the air pump 10, and the other end of the aeration pipe 11 passes through the tank body of the main reactor 1 in a sealed manner and is connected to the aeration head 12. The aeration system 3 adopts an intermittent operation mode. During the operation stage of the aeration system 3, the dissolved oxygen concentration of the sewage inside the tank body of the main reactor 1 is maintained at 1 mg / L to 5 mg / L.

[0025] The stirring system 6 includes a stirring motor 13, a stirring shaft 14 and stirring blades 15. The stirring motor 13 is installed at the outer top end of the tank body of the main reactor 1. The stirring shaft 14 is located at the inner center of the tank body of the main reactor 1. The upper end of the stirring shaft 14 is coaxially connected to the motor shaft of the stirring motor 13. The stirring blades 15 are arranged at the bottom end of the stirring shaft 14. The stirring system 6 adopts an intermittent operation mode. During the operation stage of the stirring system 6, the stirring speed of the stirring blades 15 is maintained at 80 rpm to 200 rpm.

[0026] The water inlet system 7 includes a raw water tank 16, a water inlet pump 17 and a water inlet flowmeter 18. The water outlet of the raw water tank 16 is connected to the water inlet of the water inlet pump 17, and the water outlet of the water inlet pump 17 is connected to the water inlet of the main reactor 1. The water inlet of the main reactor 1 is located at the upper end of the main reactor 1. The water inlet flowmeter 18 is arranged on the water inlet pipeline between the water outlet of the water inlet pump 17 and the water inlet of the main reactor 1. The water inlet system 7 adopts an intermittent operation mode. During the operation of the water inlet system 7, the total water inlet volume inside the main reactor 1 is maintained at 20% - 40% of the effective volume of the main reactor 1.

[0027] The drainage system 8 includes a drainage pump 19 and a drainage flowmeter 20. The water inlet of the drainage pump 19 is connected to the drainage outlet of the main reactor 1. The drainage outlet of the main reactor 1 is located in the middle of the main reactor 1. The drainage flowmeter 20 is arranged on the drainage pipeline between the water inlet of the drainage pump 19 and the drainage outlet of the main reactor 1. The drainage system 8 adopts an intermittent operation mode.

[0028] The main reactor 1 is equipped with an online monitoring system. The online monitoring system includes a computer, a dissolved oxygen concentration meter, a sludge concentration meter and a light intensity meter. The operations of the lighting system 2, the aeration system 3, the photovoltaic power generation system 4, the energy storage system 5, the stirring system 6, the water inlet system 7 and the drainage system 8 are all uniformly controlled by the computer. The dissolved oxygen concentration in the sewage is detected in real time through the dissolved oxygen concentration meter, the sludge concentration in the sewage is monitored in real time through the sludge concentration meter, and the light intensity of the lighting system 2 is monitored in real time through the light intensity meter.

[0029] The following describes the usage process of the present invention with reference to the accompanying drawings: Example 1: The season is winter and the day length is short.

[0030] In this example, the untreated sewage is first stored in the raw water tank 16. After testing, the pollutant indicators of the untreated sewage are: COD ≤ 300 mg / L, ammonia nitrogen ≤ 40 mg / L, total phosphorus ≤ 8 mg / L. Subsequently, in order to accelerate the formation of the bacteria-algae symbiotic system, the purchased algal species of the genus Chlorella can be inoculated into the sewage. Then, the water inlet pump 17 is started to pump the sewage inoculated with the algal species of the genus Chlorella into the main reactor 1. The water inlet duration is set to 5 minutes until the total water inlet volume reaches 30% of the effective volume of the main reactor 1. Then, the stirring motor 13 is started to drive the stirring blade 15 to rotate. The stirring speed of the stirring blade 15 is set to 150 rpm and the stirring duration is set to 2 hours. During the stirring process, the sludge concentration measured online by the sludge concentration meter is 2500 mg / L.

[0031] After the 2-hour anoxic stirring stage ends, start the air pump 10 to send external air into the main reactor 1 tank, making the sewage in the aerobic aeration stage. Set the aeration duration to 4 hours. During the aerobic aeration process, online monitor the dissolved oxygen concentration of the sewage through a dissolved oxygen concentration meter, and dynamically adjust the aeration volume according to the online monitoring of the dissolved oxygen concentration until the dissolved oxygen concentration of the sewage stabilizes at 1 mg / L to 2 mg / L. At the same time, start the LED light strip synchronously during the aerobic aeration stage to provide lighting inside the tank of the main reactor 1. Adjust the average light intensity to 4000 Lux according to the light intensity data fed back by the light intensity meter, and set the lighting duration to 8 hours.

[0032] After the 4-hour aerobic aeration stage ends, enter the sedimentation stage. Set the sedimentation duration to 25 minutes. After sedimentation ends, start the drain pump 19 to drain the clarified liquid from the main reactor 1. Set the drainage duration to 5 minutes. Then only maintain the lighting of the LED light strip inside the tank of the main reactor 1 until the 8-hour lighting duration ends and the LED light strip is turned off. During the operation of the LED light strip, if the power supply of the photovoltaic power generation system 4 is insufficient, switch to the energy storage system 5 for supplementary power supply.

[0033] After the clarified liquid is completely discharged from the main reactor 1, set the downtime of the main reactor 1 to 17.5 hours. When the downtime ends, restart the inlet pump 17 to start the next cycle and continue sewage treatment. Through the water quality analysis of the treated sewage, the results show that the removal rates of COD, ammonia nitrogen, and total phosphorus can reach over 90%, 80%, and 75% respectively, fully meeting the requirements of the sewage discharge standard.

[0034] Example 2: The season is summer and the day length is relatively long.

[0035] In this example, first store the untreated sewage in the original water tank 16. After testing the untreated sewage, its pollutant indicators are: COD ≤ 300 mg / L, ammonia nitrogen ≤ 40 mg / L, total phosphorus ≤ 8 mg / L; Subsequently, in order to accelerate the formation of the bacteria-algae symbiotic system, green algae species collected from nature can be inoculated into the sewage. Then start the inlet pump 17 to pump the sewage inoculated with green algae species into the tank of the main reactor 1. Set the inlet duration to 8 minutes until the total inlet volume reaches 40% of the effective volume of the main reactor 1 tank. Then start the stirring motor 13 to drive the stirring paddle 15 to rotate. Set the stirring speed of the stirring paddle 15 to 180 rpm and the stirring duration to 2 hours. During the stirring process, the sludge concentration measured online by the sludge concentration meter is 4000 mg / L.

[0036] When the 2-hour anoxic stirring stage ends, start the air pump 10 to send external air into the main reactor 1 tank, so that the sewage is in the aerobic aeration stage. Set the aeration duration to 5 hours. During the aerobic aeration process, online monitor the dissolved oxygen concentration of the sewage through the dissolved oxygen concentration meter, and dynamically adjust the aeration volume according to the online monitoring of the dissolved oxygen concentration until the dissolved oxygen concentration of the sewage stabilizes at 1.5 mg / L to 2.5 mg / L. At the same time, start the LED light strip synchronously during the aerobic aeration stage to provide lighting inside the tank of the main reactor 1. Adjust the average light intensity to 5000 Lux according to the light intensity data feedback by the light intensity meter, and set the lighting duration to 12 hours.

[0037] When the 5-hour aerobic aeration stage ends, enter the sedimentation stage. Set the sedimentation duration to 30 minutes. After sedimentation, start the drain pump 19 to discharge the clarified liquid from the main reactor 1. Set the drainage duration to 8 minutes. Then only maintain the lighting of the LED light strip inside the tank of the main reactor 1 until the 12-hour lighting duration ends and the LED light strip is turned off. During the operation of the LED light strip, if the power supply of the photovoltaic power generation system 4 is insufficient, switch to the energy storage system 5 for supplementary power supply.

[0038] When the clarified liquid is completely discharged from the main reactor 1, set the downtime of the main reactor 1 to 16.5 hours. When the downtime ends, restart the feed pump 17 to start the next cycle and continue sewage treatment. Through the water quality analysis of the treated sewage, the results show that the removal rates of COD, ammonia nitrogen, and total phosphorus can reach over 90%, 80%, and 75% respectively, fully meeting the requirements of the sewage discharge standard.

[0039] The solutions in the embodiments are not intended to limit the protection scope of the present invention. Any equivalent implementation or change without departing from the present invention is included in the protection scope of the present invention.

Claims

1. A bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply, characterized in that: It includes a main reactor, a lighting system, an aeration system, a photovoltaic power generation system, an energy storage system, a stirring system, a water inlet system and a drainage system; the main reactor adopts a vertical transparent tank structure, and the bottom of the tank of the main reactor is connected to the aeration system; the lighting system is arranged on the outer surface of the tank body of the main reactor; the photovoltaic power generation system serves as the main power supply for the lighting system, the aeration system, the stirring system, the water inlet system and the drainage system, and the photovoltaic power generation system serves as a charging power supply for the energy storage system; the energy storage system serves as a supplementary power supply for the lighting system; the stirring system is arranged inside the tank of the main reactor; the water inlet system is connected to the water inlet of the tank of the main reactor; the drainage system is connected to the drainage outlet of the tank of the main reactor.

2. According to claim 1, a bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply is characterized by: The operation time of the main reactor is 6h~8h, and the shutdown time of the main reactor is 16h~18h; during the operation stage of the main reactor, the water inlet time of the water inlet system is 5min~10min, the anaerobic stirring time of the stirring system is 2h~3h, the aerobic aeration time of the aeration system is 3h~6h, the sedimentation time after aeration is 25min~30min, and the drainage time of the drainage system is 5min~10min.

3. According to claim 1, a bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply is characterized by: The tank body of the main reactor is filled with polyurethane soft filler, the particle shape of the polyurethane soft filler is a cube, and the side length of the cube is 20mm-40mm. The filling amount of the polyurethane soft filler is 10%-30% of the volume of the tank body of the main reactor, and the total surface area of ​​the polyurethane soft filler is not less than 6000m3 per cubic meter. 2 .

4. According to claim 1, a bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply is characterized by: The lighting system includes an LED light strip, which is spirally wound and fixed on the outer surface of the tank body of the main reactor. The protection level of the LED light strip is not less than IP65, and the average light intensity applied by the LED light strip to the inside of the main reactor tank body is 3500Lux to 6000Lux.

5. According to claim 4, a bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply is characterized by: During the operation of the main reactor, the LED light strip applies illumination to the interior of the main reactor tank for 8 hours to 12 hours, and the light-dark cycle ratio inside the main reactor tank is (8 to 12):(12 to 16).

6. According to claim 1, a bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply is characterized by: The aeration system comprises an air pump, an aeration pipe and an aeration head, wherein the aeration head is located at the inner bottom end of the main reactor tank body, the air pump is located outside the main reactor tank body, one end of the aeration pipe is connected to the air pump, and the other end of the aeration pipe is sealed and passes through the main reactor tank body to be connected to the aeration head; the aeration system adopts an intermittent operation mode, and during the operation stage of the aeration system, the dissolved oxygen concentration of the sewage inside the main reactor tank body is kept at 1 mg / L to 5 mg / L.

7. According to claim 1, a bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply is characterized by: The stirring system includes a stirring motor, a stirring shaft and a stirring blade. The stirring motor is installed on the external top end of the main reactor tank body, the stirring shaft is located at the internal center of the main reactor tank body, the upper end of the stirring shaft is coaxially connected to the motor shaft of the stirring motor, and the stirring blade is arranged at the bottom end of the stirring shaft; the stirring system adopts an intermittent operation mode, and during the operation stage of the stirring system, the stirring speed of the stirring blade is between 80rpm and 200rpm.

8. According to claim 1, a bacteria-algae symbiotic device suitable for treating rural sewage with intermittent photovoltaic energy supply is characterized by: The water inlet system includes a raw water tank, a water inlet pump and a water inlet flow meter. The water outlet of the raw water tank is connected to the water inlet of the water inlet pump, and the water outlet of the water inlet pump is connected to the water inlet of the tank body of the main reactor. The tank body water inlet is located at the upper end of the tank body of the main reactor. The water inlet flow meter is arranged on the water inlet pipeline between the water outlet of the water inlet pump and the water inlet of the tank body of the main reactor. The water inlet system adopts an intermittent operation mode. During the operation stage of the water inlet system, the total water inflow inside the tank body of the main reactor is 20% to 40% of the effective volume of the tank body of the main reactor.

9. The bacterial-algal symbiotic device for treating rural sewage with intermittent photovoltaic energy supply according to claim 1 is characterized by: The drainage system includes a drainage pump and a drainage flowmeter. The water inlet of the drainage pump is connected to the tank drain outlet of the main reactor. The tank drain outlet is located in the middle of the tank body of the main reactor. The drainage flowmeter is arranged on the drainage pipeline between the water inlet of the drainage pump and the tank drain outlet of the main reactor. The drainage system adopts an intermittent operation mode.

10. The bacteria-algae symbiotic device for treating rural sewage with intermittent photovoltaic energy supply according to claim 1 is characterized by: The main reactor is equipped with an online monitoring system, which includes a computer, a dissolved oxygen concentration meter, a sludge concentration meter and a light intensity meter. The operation of the lighting system, aeration system, photovoltaic power generation system, energy storage system, stirring system, water inlet system and drainage system are all uniformly controlled by the computer. The dissolved oxygen concentration meter is used to detect the dissolved oxygen concentration in the sewage in real time, the sludge concentration meter is used to monitor the sludge concentration in the sewage in real time, and the light intensity meter is used to monitor the light intensity of the lighting system in real time.

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