A method for treating wastewater produced by cell culture media operations

Abstract

The present application relates to a kind of processing methods for wastewater produced by cell culture medium operation, comprising the following steps: S1: wastewater is input flocculation sedimentation tank, and flocculation sedimentation is carried out;S2: the supernatant obtained in step S1 is input high-pressure pulse electroflocculation device, and the pollutants in wastewater are decomposed and separated;S3: the water produced in step S2 is input dynamic hydrolysis acidification tank after mud-water separation and water quality and quantity adjustment, and hydrolysis acidification is carried out, to improve the biodegradability of wastewater;S4: the water produced in step S3 is input anaerobic tank, to remove heavy metals, bacteria and viruses in wastewater;S5: the water produced in step S4 is input anoxic tank, nitrate and nitrification liquid are added in anoxic tank, which can effectively remove carbon and nitrogen;S6: the water produced in step S5 is input aerobic tank, to carry out ammonification and nitrification;S7: the water produced in step S6 is input dissolved air flotation device, to remove SS and TP;S8: the water produced in step S7 is input multi-media filter, to obtain final water after filtration.

Description

Technical Field

[0001] This invention belongs to the field of biological wastewater treatment technology, specifically relating to a method for treating wastewater generated from cell culture medium operations. Background Technology

[0002] In drug or vaccine research and many biochemical studies, bacterial culture experiments are conducted. Laboratories or research institutes will face the problem of treating wastewater generated from cell culture. This type of wastewater mainly comes from disinfection wastewater discharged from bacterial culture laboratories, water used for cleaning culture dishes, or lost liquid reagents. Because the experimental subjects and reagents used in each research project are different, the composition of cell culture wastewater is relatively complex. It contains a large number of microorganisms and recalcitrant substances. Some cell culture experiments may also contain toxic and harmful substances. Cell culture wastewater is discharged irregularly, has a high concentration, and fluctuates greatly in water quality, making it difficult to treat. Summary of the Invention

[0003] To address the above problems, this invention provides a method for treating wastewater generated during cell culture medium processing, comprising the following steps:

[0004] (I) Preprocessing stage:

[0005] S1: Wastewater is fed into the flocculation sedimentation tank for flocculation and sedimentation;

[0006] S2: The supernatant obtained in step S1 is fed into a high-voltage pulse electrocoagulation device to decompose and separate pollutants in the wastewater;

[0007] S3: The wastewater produced in step S2 is separated into mud and water in a sedimentation tank, and then its quality and quantity are adjusted in an equalization tank before being fed into a dynamic hydrolysis acidification tank for hydrolysis acidification to further reduce the COD of the wastewater and improve its biodegradability.

[0008] (II) Biochemical treatment stage:

[0009] S4: The permeate from step S3 enters the anaerobic tank to remove heavy metals, bacteria and viruses from the wastewater;

[0010] S5: The permeate from step S4 enters the anoxic tank. Nitrate and nitrification liquid are added to the anoxic tank, which can effectively remove carbon and nitrogen.

[0011] S6: The permeate from step S5 enters the aerobic tank, where ammoniation and nitrification occur under aeration and oxygenation conditions.

[0012] (III) Deep Processing Stage:

[0013] S7: The wastewater from step S6 enters the dissolved air flotation device, where compressed air is forced to dissolve in the water under pressure, forming a cluster of microbubbles. These microbubbles come into contact with suspended solids in the wastewater and float to the surface, thus achieving the purpose of removing SS (suspended solids) and TP (total phosphorus).

[0014] S8: The product water from step S7 enters a multi-media filter and is filtered to obtain the final product water.

[0015] The wastewater produced from cell culture medium processing in this invention has a pH of 5-6. The flocculant in step S1 is selected from polyaluminum chloride (PAC), polyferric sulfate (PFS), and polysilicic acid (PS). Some colloidal particles and larger particles in the wastewater undergo flocculation reaction and separate and settle from the water. The sludge generated is pumped from the flocculation sedimentation tank into the sludge thickening tank for further sludge treatment.

[0016] Optionally, in step S2, the electrocoagulation device applies a pulsed high voltage to the wastewater to generate an electrochemical reaction, effectively removing pollutants such as CN, grease, phosphate, COD and SS from the wastewater, while also sterilizing, decolorizing and deodorizing the wastewater.

[0017] Optionally, in step S3, the sedimentation tank is selected from inclined plate sedimentation tank, horizontal flow sedimentation tank, and radial flow sedimentation tank. After sludge-water separation, the sludge is pumped into the sludge thickening tank by the sludge discharge pump and then undergoes subsequent conventional treatment. The supernatant of the sedimentation tank overflows into the equalization tank. The wastewater is regulated in the equalization tank to adjust the water quality and control the water volume, and then input into the dynamic hydrolysis acidification tank.

[0018] Optionally, in step S4, the anaerobic tank is a photocatalytic activated carbon membrane reactor.

[0019] Optionally, in step S5, adding nitrate and nitrification liquid to the anoxic tank can effectively remove carbon and nitrogen, and the nitrate content in the anoxic tank is 1-3 ppm.

[0020] Optionally, in step S6, the nitrified liquor from the aerobic tank is returned to the anoxic tank at a return ratio of 120-150%. In the aerobic tank, nitrogen in the water is converted into NO through ammoniation and nitrification. 2- and NO 3- ;

[0021] The permeate from the aerobic tank is fed into the effluent reaction tank for denitrification; the supernatant from the effluent reaction tank is fed into the dissolved air flotation device.

[0022] In the effluent reaction tank, NO produced by the aerobic tank 2- and NO 3- Under anaerobic conditions, denitrifying bacteria reduce nitrates, producing N2 and N2O, which are then discharged from the water, thus removing nitrogen from the water.

[0023] Optionally, in step S7, the dissolved air flotation device is set with differential multi-stage pressure, for example, at 0.25 MPa, 0.35 MPa and 0.4 MPa, so that suspended solids in the water are treated more thoroughly;

[0024] The sludge discharged from the bottom of the dissolved air flotation device can be partially returned to the anaerobic tank, while the remainder is treated using conventional sludge treatment methods.

[0025] Optionally, in step S8, the filter media of the multi-media filter is selected from quartz sand, anthracite, and manganese sand, and the turbidity of the final produced water reaches below 3 degrees, and meets the direct emission limit in the "Emission Limits for Water and Air Pollutants in the Biopharmaceutical Industry (DB32 / 3560-2019)".

[0026] Optionally, the aerobic tank is provided with several baffles from top to bottom inside. One end of the baffle is fixed to the inner wall of the aerobic tank, and the other end is suspended. Two adjacent baffles are fixed to the two opposite inner walls of the aerobic tank, so that the two baffles are arranged in an alternating pattern in the upper and lower space, so that the water flow forms a baffle along the baffle in the aerobic tank.

[0027] The inlet pipe of the aerobic tank is located at the top of the aerobic tank, the outlet pipe is located at the bottom of the aerobic tank, and the aeration pipe is located in the middle and bottom of the aerobic tank.

[0028] Optionally, in the biochemical treatment stage, the anaerobic tank and the aerobic tank are arranged side by side, the anoxic tank is located below the anaerobic tank, and the effluent reaction tank is located below the aerobic tank.

[0029] The anaerobic tank is equipped with a main inlet pipe at the top and a first drain pipe at the bottom. The first drain pipe connects to the top of the anoxic tank, which inputs the anaerobic wastewater into the anoxic tank. The bottom of the anoxic tank is connected to a second drain pipe, which connects upwards to the inlet of the aerobic tank, inputting the anoxic wastewater into the aerobic tank. The outlet of the aerobic tank connects to the top of the effluent reaction tank, and the lower part of the effluent reaction tank is equipped with a main outlet pipe for discharging the produced water.

[0030] When the wastewater treated by this invention passes through the anode plate of the electrocoagulation device, a dense oxide film is formed on the surface of the anode plate and adheres to the electrode surface. This not only causes electrode passivation and affects the performance of the electrode, but also may block the through holes of the anode plate with long-term use. The colloidal particles generated during electrocoagulation are very easy to deposit on the electrode surface and also easily block the through holes of the anode plate.

[0031] Optionally, the electrocoagulation device has several anode plates and several cathode plates alternately arranged inside, both of which are horizontally arranged. The bottom of the electrocoagulation device is provided with a water distribution pipe and an aeration pipe, and the top is provided with a water outlet pipe.

[0032] The anode plate covers the horizontal cross-section of the electrocoagulation device. The lower surface of the anode plate is uniformly provided with several water-passing conical holes, and the upper surface of the anode plate is uniformly provided with several sets of water-passing holes. One water-passing conical hole corresponds to one set of water-passing holes.

[0033] There is a gap between one side of the cathode plate and the inner wall of the electrocoagulation device, which allows sewage to pass through the cathode plate.

[0034] Optionally, a cathode plate is set between two adjacent anode plates, the number of anode plates and cathode plates are equal, and all are connected to the power supply device outside the electrocoagulation device through a circuit.

[0035] The electrocoagulation device is cylindrical, and the anode plate is circular.

[0036] Optionally, each group of water passages includes several inclined holes arranged at an angle, with the tops of the several inclined holes in each group forming a circle on the upper surface of the anode plate, and the rest of the inclined holes inside the anode plate.

[0037] The bottom of the inclined holes in the same group are all connected to the top of the corresponding water-passing conical holes, so that sewage passes through the water-passing conical holes and inclined holes through the anode plate.

[0038] Optionally, a liftable cleaning plate is provided below the anode plate. The cleaning plate includes an outer circular frame and several inner cleaning cones. Each cleaning cone corresponds to a water-passing conical hole. The cleaning cones can rotate in place and have protruding external threads on their surfaces. The shape of the cleaning cones is adapted to the shape of the water-passing conical holes, and the protruding external threads of the cleaning cones are adapted to the threads on the inner wall of the water-passing conical holes. When the cleaning plate rises, the cleaning cones can penetrate into the water-passing conical holes to clean the inner wall of the water-passing conical holes.

[0039] Optionally, the inner wall of the electrocoagulation device below the anode plate is provided with a horizontal circular track and several vertical tracks. The several vertical tracks are evenly arranged along the circumference of the inner wall of the electrocoagulation device. A slider is engaged in each vertical track. The outer side of the circular frame is connected to all the sliders, so that the cleaning plate can move up and down along the vertical tracks. At this time, the cleaning cone on the cleaning plate corresponds one-to-one with the position of the water-passing cone hole on the lower surface of the anode plate. The top of the vertical track is close to the lower surface of the anode plate.

[0040] The horizontal circular track is set horizontally and runs around the circumference of the inner wall of the electrocoagulation device. Each vertical track passes through and connects to the horizontal circular track in its respective vertical direction.

[0041] The distance between the horizontal circular track and the lower surface of the anode plate is less than the height of the cleaning cone. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the processing technology in Example 1;

[0043] Figure 2 This is a schematic diagram of the electrocoagulation device in Example 1;

[0044] Figure 3 This is a top view of the cathode plate;

[0045] Figure 4 This is a schematic diagram of the aerobic tank in Example 2;

[0046] Figure 5 This is a schematic diagram of the biochemical treatment system in Example 3;

[0047] Figure 6 This is a schematic diagram of the lower surface structure of the anode plate;

[0048] Figure 7 This is a schematic diagram of the upper surface structure of the anode plate;

[0049] Figure 8 This is a schematic diagram of the cross-section of the anode plate;

[0050] Figure 9 This is a schematic diagram of the structure of the lower surface of the agitator;

[0051] Figure 10 This is a schematic diagram of the cleaning board structure;

[0052] Figure 11 This is a schematic diagram of the cleaning plate and the anode plate.

[0053] In the attached diagram, 1-inlet pipe, 2-outlet pipe, 3-aerobic tank, 4-baffle plate, 5-first aeration pipe, 6-anaerobic tank, 7-anoxic tank, 8-effect reaction tank, 9-main inlet pipe, 10-first drain pipe, 11-second drain pipe, 12-third drain pipe, 13-main outlet pipe, 14-anode plate, 15-cathode plate, 16-water distribution pipe, 17-second aeration pipe, 18-gap, 19-stirring paddle, 20-blade, 21-conical water passage hole, 22-water passage hole, 23-inclined hole, 24-cleaning plate, 25-circular frame, 26-cleaning cone, 27-support rod, 28-slider, 29-brush. Detailed Implementation

[0054] The wastewater produced from the cell culture medium operations in the following examples and comparative treatments has the following water quality: COD content 30000 mg / L, SS content 3000 mg / L, BOD content 20000 mg / L, NH3-N content 3000 mg / L, TN content 3000 mg / L, TP content 2000 mg / L, and pH 6.0.

[0055] Example 1

[0056] This embodiment provides a method for treating wastewater generated during cell culture medium processing, such as... Figure 1 This includes the following steps:

[0057] (I) Preprocessing stage:

[0058] S1: Wastewater enters the flocculation sedimentation tank, with a design flow rate of 100m³. 3 / d, flocculation and sedimentation are carried out. The flocculants used are polyaluminum chloride and polyferric sulfate. The flocculant concentration is 0.5% and the flocculant dosage is 20.16L / h.

[0059] S2: The supernatant obtained in step S1 is fed into the electrocoagulation device, where a pulsed high voltage is applied to the wastewater to generate an electrochemical reaction, which decomposes and separates the pollutants in the wastewater, effectively removing pollutants such as CN, oil, phosphate, COD and SS from the wastewater. At the same time, it can also sterilize, decolorize and deodorize the wastewater.

[0060] S3: The water produced in step S2 is separated into mud and water in an inclined plate sedimentation tank. The effluent from the inclined plate sedimentation tank has a COD of about 1800 mg / L, SS reduced to about 120 mg / L, NH3-N reduced to about 135 mg / L, TP reduced to about 5 mg / L, and TN reduced to about 460 mg / L.

[0061] After the effluent passes through the equalization tank to adjust the water quality and quantity, it is fed into the dynamic hydrolysis acidification tank for hydrolysis acidification, which further reduces the COD of the wastewater to about 1350 mg / L and improves its biodegradability.

[0062] (II) Biochemical treatment stage:

[0063] S4: The wastewater from step S3 enters the anaerobic tank, which is a photocatalytic activated carbon membrane reactor. This is beneficial for the cultivation of anaerobic bacteria and enhances the anaerobic reaction effect, and is used to remove heavy metals, bacteria and viruses from the wastewater.

[0064] S5: The permeate from step S4 enters the anoxic tank. Nitrate and nitrification liquid are added to the anoxic tank to effectively remove carbon and nitrogen. The nitrate content in the anoxic tank is 1 ppm.

[0065] S6: The permeate from step S5 enters the aerobic tank, where ammoniation and nitrification occur under aeration and oxygenation conditions; the nitrified liquid from the aerobic tank is returned to the anoxic tank, with a nitrification liquid return ratio of 150%.

[0066] The aerobic tank consists of a product water input and output reaction tank. The aerobic tank has a conventional structure with aeration pipes at the bottom and a hollow square tank body inside, which contains aerobic sludge.

[0067] The product water quality in step S6 is as follows: COD reduced to about 70 mg / L, BOD reduced to about 15 mg / L, SS reduced to about 70 mg / L, NH3-N reduced to about 8 mg / L, TP reduced to about 1 mg / L, and TN reduced to about 18 mg / L.

[0068] (III) Deep Processing Stage:

[0069] S7: The wastewater from step S6 enters the dissolved air flotation device, where compressed air is forced to dissolve in the water under pressure, forming a cluster of microbubbles that come into contact with suspended solids in the wastewater and float to the surface, thereby achieving the purpose of removing SS and CODcr.

[0070] The dissolved air flotation device is equipped with multi-stage pressure differentials, at 0.25 MPa, 0.35 MPa and 0.4 MPa, which makes the treatment of suspended solids in water more thorough;

[0071] S8: The permeate from step S7 enters a multi-media filter. The filter media of the multi-media filter is quartz sand. After filtration, the final permeate is obtained. The final permeate water quality is COD = 53.5 mg / L, SS = 29.2 mg / L, BOD = 14.7 mg / L, NH3-N = 7.3 mg / L, TN = 18.4 mg / L, and TP = 0.48 mg / L.

[0072] like Figure 2 and Figure 3 In this embodiment, two anode plates 14 and two cathode plates 15 are alternately arranged inside the electrocoagulation device. Both the anode plates 14 and the cathode plates 15 are horizontally arranged. The bottom of the electrocoagulation device is provided with a water distribution pipe 16 and a second aeration pipe 17, and the top is provided with a water outlet pipe.

[0073] The anode plate 14 covers the horizontal cross-section of the electrocoagulation device, and its surface is uniformly covered with through holes; there is a gap 18 between one side of the cathode plate 15 and the inner wall of the electrocoagulation device, allowing wastewater to pass through the cathode plate 15. The anode plate and cathode plate are electrically connected to a power source outside the electrocoagulation device.

[0074] The second aeration pipe 17 is located below the water distribution pipe 16. The second aeration pipe 17 is connected to the air source outside the electrocoagulation device and is used to provide air and oxygen to the inside of the electrocoagulation device. The second aeration pipe 17 is a spiral second aeration pipe.

[0075] The water distribution pipe 16 is connected to the outlet of the flocculation sedimentation tank and is used to input wastewater. The water distribution pipe 16 is a pipe that can cover the cross-section of the electrocoagulation device, which is conducive to the uniform water intake into the tank.

[0076] Wastewater is fed into the bottom of the electrocoagulation device. Under the action of water flow and aeration, the wastewater flows upward and passes sequentially through the horizontally arranged anode and cathode plates 14. Under the action of an external electric field, the anode plate 14 dissolves to generate metal ions, which, through hydrolysis and polymerization, produce a series of mononuclear and polynuclear hydroxyl complexes and hydroxides. These ions then remove pollutants from the water through flocculation, adsorption, and precipitation. Simultaneously, a reduction reaction occurs at the cathode, generating hydrogen bubbles with microstructures. These bubbles, through flotation, separate pollutants from the water and carry them to the surface for removal.

[0077] A cathode plate 15 is provided between two adjacent anode plates 14. The number of anode plates 14 and cathode plates 15 is equal, and they are all connected to the power supply device outside the electrocoagulation device through a circuit.

[0078] The electrocoagulation device is cylindrical, and the anode plate 14 is circular.

[0079] Example 2

[0080] This embodiment provides a method for treating wastewater generated during cell culture medium processing, which is the same as in Embodiment 1, except that... Figure 4 The aerobic tank 3 is a cuboid with a length-to-width ratio of 3:1. Inside the aerobic tank 3, two baffles 4 are arranged from top to bottom. One end of each baffle 4 is fixed to the inner wall of the aerobic tank 3, while the other end is suspended. Two adjacent baffles 4 are fixed to opposite inner walls of the aerobic tank 3, creating a staggered arrangement that causes the water flow to bend along the baffles 4 within the aerobic tank 3. Specifically, the left end of the upper baffle 4 is fixed to the left inner wall of the aerobic tank 3, while the right end is suspended and points towards the right inner wall of the aerobic tank 3; the right end of the lower baffle 4 is fixed to the right inner wall of the aerobic tank 3, while the left end is suspended and points towards the left inner wall of the aerobic tank 3.

[0081] The inlet pipe 1 of the aerobic tank 3 is located at the top of the aerobic tank 3, the outlet pipe 2 is located at the bottom of the aerobic tank 3, and the first aeration pipe 5 is located in the middle and bottom of the aerobic tank 3.

[0082] The baffle 4 is inclined, with the fixed end higher than the suspended end, and has a downward slope of 3‰. The baffle 4 is made of corrosion-resistant concrete slab, which deflects the water flow and increases the aeration rate.

[0083] Example 3

[0084] This embodiment provides a method for treating wastewater generated during cell culture medium processing, which is the same as in Embodiment 2, except that... Figure 5 In the biochemical treatment stage, the anaerobic tank 6 and the aerobic tank are arranged side by side, the anoxic tank 7 is located below the anaerobic tank 6, and the effluent reaction tank 8 is located below the aerobic tank.

[0085] The anaerobic tank 6 is equipped with a main inlet pipe 9 at the top and a first drain pipe 10 at the bottom. The first drain pipe 10 is connected to the top of the anoxic tank 7, and the wastewater after anaerobic treatment is input into the anoxic tank 7. The bottom of the anoxic tank 7 is connected to a second drain pipe 11, which is connected upward to the inlet pipe of the aerobic tank, and the wastewater after anoxic treatment is input into the aerobic tank. The outlet pipe of the aerobic tank is connected to the top of the effluent reaction tank 8, and the lower part of the effluent reaction tank 8 is equipped with a main outlet pipe 13 for discharging the produced water.

[0086] The bottom of the aerobic tank is equipped with a third drain pipe 12, which connects downwards to the top of the anoxic tank 7, returning the nitrified liquid from the aerobic tank to the anoxic tank 7. This configuration reduces the floor space required and eliminates the need for a nitrified liquid return pump, allowing the nitrified liquid to flow by gravity from the upper aerobic tank into the lower anoxic tank 7.

[0087] Example 4

[0088] This embodiment provides a method for treating wastewater generated during cell culture medium processing, which is the same as in Embodiment 3, except that... Figures 6-11 As shown, the lower surface of the anode plate 14 is uniformly provided with a plurality of water-passing conical holes 21, and the upper surface of the anode plate 14 is uniformly provided with a plurality of water-passing holes 22, with one water-passing conical hole 21 corresponding to one set of water-passing holes 22.

[0089] Each group of water passage holes 22 includes five inclined holes 23 arranged at an angle. The tops of the five inclined holes 23 in each group of water passage holes 22 form a circle on the upper surface of the anode plate 14, and the rest of the inclined holes 23 are inside the anode plate 14.

[0090] The bottom of the inclined holes 23 in the same group are all connected to the top of the corresponding water-passing conical holes 21, so that sewage passes through the water-passing conical holes 21 and the inclined holes 23 and passes through the anode plate 14.

[0091] The water-passing conical hole 21 is a cone shape with a smaller top and a larger bottom, and the inner wall is uniformly provided with continuous threads. When sewage enters the water-passing conical hole 21, it plays a certain guiding and rectifying role. That is, the sewage spirals upward along the inner wall of the water-passing conical hole 21 and enters the anode plate 14, and then exits the anode plate 14 through the inclined hole 23.

[0092] The bottoms of the inclined holes 23 in the same group are connected to each other to form a unified water inlet position, and the top of the water-passing conical hole 21 is connected to the five inclined holes 23 in the same group through this water inlet position.

[0093] The tops of the five inclined holes 23 of each group of water passage holes 22 form a circle on the upper surface of the anode plate 14. The center of this circle coincides with the center of the bottom surface of the water passage cone hole 21, ensuring that the water passage cone hole 21 delivers water evenly to each inclined hole 23.

[0094] Because the conical orifice 21 is smaller at the top and larger at the bottom, the wastewater is accelerated after passing through the conical orifice 21 and then evenly distributed into the five corresponding inclined orifices 23. It exits the anode plate 14 along the inclined orifice 23 channels inside the anode plate 14. Since the top of the inclined orifice 23 in the same group forms a circle, the inclined directions of the channels in the same group of inclined orifices 23 are different. This causes the spiral accelerated water flow that has just left the conical orifice 21 to randomly enter the channels in different directions and exit the anode plate 14 at different inclinations, resulting in a dimensionally rich turbulent water flow. This improves the electrical treatment efficiency, and the water flow can also clean up the flocs formed or accumulated above the anode plate 14, promoting the flocs to rise.

[0095] Below the anode plate 14 is a liftable cleaning plate 24. The cleaning plate 24 includes an outer circular frame 25 and multiple inner cleaning cones 26. Each cleaning cone 26 corresponds to a water-passing conical hole 21. The cleaning cone 26 can rotate in place and has protruding external threads on its surface. The shape of the cleaning cone 26 is adapted to the shape of the water-passing conical hole 21, and the protruding external threads of the cleaning cone 26 are adapted to the threads on the inner wall of the water-passing conical hole 21. When the cleaning plate 24 rises, the cleaning cone 26 can penetrate into the water-passing conical hole 21 and clean the inner wall of the water-passing conical hole 21.

[0096] The cleaning cone 26 has a flexible outer shell that can deform elastically, and a hollow interior to reduce its weight and energy consumption during rotation. A rotating motor is located at the bottom of the cleaning cone 26, and the rotating shaft of the rotating motor is connected to the bottom of the cleaning cone 26 to drive the cleaning cone 26 to rotate.

[0097] The rotating motor also has an outer casing, which is connected to the outer casing of the cleaning cone 26 to prevent wastewater from the electrocoagulation device from entering the outer casing.

[0098] The cleaning plate 24 has a hollow structure. Inside the circular frame 25, several support rods 27 support each cleaning cone 26 and its corresponding rotating motor. The specific arrangement of the support rods 27 is not limited, as long as the cleaning cone 26 and the rotating motor are stable. Other hollow positions are used for sewage to pass through the cleaning plate 24.

[0099] The inner wall of the electrocoagulation device below the anode plate 14 is provided with a horizontal circular track and five vertical tracks. The five vertical tracks are evenly arranged along the circumference of the inner wall of the electrocoagulation device. A slider 28 is locked in each vertical track. The outer side of the circular frame 25 is connected to all the sliders 28, so that the cleaning plate 24 can move up and down along the vertical tracks. At this time, the cleaning cone 26 on the cleaning plate 24 corresponds one-to-one with the position of the water-passing cone hole 21 on the lower surface of the anode plate 14. The top of the vertical track is close to the lower surface of the anode plate 14.

[0100] The horizontal circular track is set horizontally and runs around the circumference of the inner wall of the electrocoagulation device. Each vertical track passes through and connects to the horizontal circular track in its respective vertical direction.

[0101] The distance between the horizontal circular track and the lower surface of the anode plate 14 is less than the height of the cleaning cone 26.

[0102] During normal wastewater treatment, the cleaning plate 24 is positioned below the second horizontal circular track, and the cleaning plate 24 does not contact the anode plate 14. At this time, the height of the cleaning plate 24 is at the bottom of each vertical track, preventing it from moving downwards, thus serving as a limiting function. Since the water-passing conical hole 21 is the inevitable path for wastewater, an oxide film will form on the inner wall of the water-passing conical hole 21 after a period of operation, requiring cleaning. The control slider 28 moves the cleaning plate 24 upwards along the vertical track to the top of the vertical track. At this time, the cleaning cone 26 extends into the corresponding water-passing conical hole 21 and fits against the inner wall of the water-passing conical hole 21 through the cooperation of internal and external threads. At this point, the cleaning plate 24 can no longer move upwards, also serving as a limiting function. Each cleaning cone 26 rotates independently, cleaning the oxide film on the inner wall of the water-passing conical hole 21. After cleaning, the cleaning plate 24 moves downwards along the vertical guide rail, disengaging from the anode plate 14. If each cleaning session is short, it can be done in multiple sessions without affecting the water intake and flow of the electrocoagulation device, allowing for continuous wastewater treatment. However, if each cleaning session is long, it will affect the water flow through the conical orifice 21, requiring the water intake to be stopped.

[0103] When the electrocoagulation device has been running for a long time, an oxide film accumulates on the lower surface of the anode plate 14, which needs to be cleaned. The cleaning plate 24 moves upward along the vertical guide rail to the horizontal circular track. At this time, the cleaning cone 26 extends into the water-passing conical hole 21. The cleaning plate 24 is controlled to rotate horizontally along the horizontal circular track. When the cleaning cone 26 faces the position of the anode plate 14 that is not in the water-passing conical hole 21, the cleaning cone 26 is pressed and pressed against the lower surface of the anode plate 14. As the cleaning plate 24 rotates, the cleaning cone 26 can clean the lower surface of the anode plate 14.

[0104] The electrocoagulation device is also equipped with two stirring paddles 19. Each stirring paddle 19 is located above the corresponding anode plate 14. Each stirring paddle 19 includes four blades 20. All four blades 20 penetrate the center of the stirring paddle 19 and are evenly distributed radially. The lower surface of each blade 20 is provided with two rows of brushes 29. The roots of the brushes 29 are parallel to each other. The bristles of the two rows of brushes 29 are inclined towards each other. The inclination angle of the bristles is the same as the inclination angle of the inclined hole 23. This is used to clean the inside of the inclined hole 23 on the anode plate 14 and the upper surface of the anode plate 14.

[0105] The stirring shaft of the stirring paddle 19 passes through the top surface of the electrocoagulation device and is connected to an external motor. The motor can be adjusted up and down, thereby adjusting the distance between the stirring paddle 19 and the lower surface of the anode plate 14. This allows the blades 20 to rise and the brushes 29 to not contact the anode plate 14 when the anode plate 14 does not need cleaning. The stirring shaft passes through each anode plate 14 and cathode plate 15.

[0106] When the agitator 19 rotates, the inclined bristles can extend into the inclined hole 23 along the tangential direction to clean the oxide film inside the inclined hole 23. Since the bristles are soft and deformable, they are easy to enter and exit the inclined hole 23 and can also clean the oxide film on the upper surface of the anode plate 14.

[0107] The width of the gap 18 between the cathode plate 15 and the inner wall of the electrocoagulation device is in the ratio of 1:6 to the radius of the cathode plate 15, so that the rising sewage passes through the cathode plate 15 through the gap 18.

[0108] The gaps 18 between two adjacent cathode plates 15 are positioned relative to each other. For example, the gap 18 of the next cathode plate 15 is located on the right side, and the gap 18 of the previous cathode plate 15 is located on the left side, so that the sewage flow forms a tortuous and meandering water flow between the cathode plates 15, prolonging the sewage residence time and improving the treatment effect.

Claims

1. A method for treating wastewater generated during cell culture medium processing, characterized in that, Includes the following steps: (a) Preprocessing stage: S1: Wastewater is fed into the flocculation sedimentation tank for flocculation and sedimentation; S2: The supernatant obtained in step S1 is fed into the electrocoagulation device to decompose and separate pollutants in the wastewater; S3: The wastewater produced in step S2 is separated into mud and water in a sedimentation tank, then fed into a dynamic hydrolysis acidification tank after passing through an equalization tank, to further reduce the COD of the wastewater and improve its biodegradability. (II) Biochemical treatment stage: S4: The permeate from step S3 enters the anaerobic tank to remove heavy metals, bacteria and viruses from the wastewater; S5: The permeate from step S4 enters the anoxic tank, which can effectively remove carbon and nitrogen. S6: The permeate from step S5 enters the aerobic tank, where ammoniation and nitrification occur under aeration and oxygenation conditions. (III) Deep Processing Stage: S7: The wastewater from step S6 enters the dissolved air flotation device, where compressed air is forced to dissolve in the water under pressure, forming a cluster of microbubbles that come into contact with suspended solids in the wastewater and float to the surface. S8: The water produced in step S7 enters a multi-media filter and is filtered to obtain the final water. The electrocoagulation device has several anode plates and several cathode plates alternately arranged inside. Both the anode plates and cathode plates are horizontally arranged. The anode plates cover the horizontal cross-section of the electrocoagulation device. The lower surface of the anode plate is uniformly provided with several water-passing conical holes, and the upper surface of the anode plate is uniformly provided with several sets of water-passing holes. One water-passing conical hole corresponds to one set of water-passing holes. Each group of water passages includes several inclined holes arranged at an angle. The tops of the several inclined holes in each group of water passages form a circle on the upper surface of the anode plate, and the rest of the inclined holes are inside the anode plate. The bottom of the inclined holes in the same group are all connected to the top of the corresponding water-passing conical holes, so that sewage passes through the water-passing conical holes and inclined holes through the anode plate; The water-passing conical hole is a cone shape with a smaller top and a larger bottom, and the inner wall is uniformly provided with continuous threads. Wastewater spirals upward along the inner wall of the water-passing conical hole and enters the anode plate, and then exits the anode plate through the inclined hole. The bottoms of the inclined holes in the same group are connected to each other to form a unified water inlet position, and the top of the water-passing conical hole is connected to several inclined holes in the same group through this water inlet position.

2. The method of claim 1, wherein the method is characterized by: The flocculant in step S1 is selected from polyaluminum chloride, polyferric sulfate, and polysilicic acid; In step S2, the electrocoagulation device applies a pulsed high voltage to the wastewater to generate an electrochemical reaction; In step S3, the sedimentation tank is selected from inclined plate sedimentation tank, horizontal flow sedimentation tank, and radial flow sedimentation tank. After sludge-water separation, the sludge is pumped into the sludge thickening tank by the sludge discharge pump, and the supernatant of the sedimentation tank overflows into the equalization tank. The wastewater is adjusted in the equalization tank to regulate the water quality and control the water volume, and then input into the dynamic hydrolysis acidification tank.

3. The method of claim 1, wherein the method is characterized by: In step S5, adding nitrate and nitrification liquid to the anoxic tank can effectively remove carbon and nitrogen. The nitrate content in the anoxic tank is 1-3 ppm. In step S6, the nitrified liquor from the aerobic tank is returned to the anoxic tank at a return ratio of 120-150%. In the aerobic tank, nitrogen in the water is converted into NO2 through ammoniation and nitrification. - and NO3 - ; The permeate from the aerobic tank is fed into the effluent reaction tank for denitrification, and the supernatant from the effluent reaction tank is fed into the dissolved air flotation device.

4. The method of claim 1, wherein the method is characterized by: The aerobic tank has several baffles arranged from top to bottom inside. One end of the baffle is fixed to the inner wall of the aerobic tank, and the other end is suspended. Two adjacent baffles are fixed to the two opposite inner walls of the aerobic tank, so that the two baffles are arranged in an alternating pattern in the upper and lower space, so that the water flow forms a baffle along the baffle in the aerobic tank. The inlet pipe of the aerobic tank is located at the top of the aerobic tank, the outlet pipe is located at the bottom of the aerobic tank, and the aeration pipe is located in the middle and bottom of the aerobic tank.

5. The method of treating waste water produced from cell media operations of claim 4, wherein, The anaerobic tank and the aerobic tank are arranged side by side, the anoxic tank is located below the anaerobic tank, and the effluent reaction tank is located below the aerobic tank. The anaerobic tank is equipped with a main inlet pipe at the top and a first drain pipe at the bottom. The first drain pipe connects to the top of the anoxic tank, which inputs the anaerobic wastewater into the anoxic tank. The bottom of the anoxic tank is connected to a second drain pipe, which connects upwards to the inlet of the aerobic tank, inputting the anoxic wastewater into the aerobic tank. The outlet of the aerobic tank connects to the top of the effluent reaction tank, and the lower part of the effluent reaction tank is equipped with a main outlet pipe for discharging the produced water.

6. The method of claim 1, wherein the method is characterized by: The electrocoagulation device is equipped with a water distribution pipe and an aeration pipe at the bottom, and a water outlet pipe at the top. There is a gap between one side of the cathode plate and the inner wall of the electrocoagulation device, which allows sewage to pass through the cathode plate.

7. The method of treating waste water produced from cell media operations of claim 6, wherein, A cathode plate is placed between two adjacent anode plates. The number of anode plates and cathode plates is equal, and they are all connected to a power supply device outside the electrocoagulation device via circuit. The electrocoagulation device is cylindrical, and the anode plates are circular.

8. The method of treating waste water produced from cell media operations of claim 7, wherein, Below the anode plate is a liftable cleaning plate. The cleaning plate includes an outer circular frame and several inner cleaning cones. Each cleaning cone corresponds to a water-passing conical hole. The cleaning cone can rotate in place and has protruding external threads on its surface. The shape of the cleaning cone matches the shape of the water-passing conical hole, and the protruding external threads of the cleaning cone match the threads on the inner wall of the water-passing conical hole. When the cleaning plate rises, the cleaning cone can penetrate into the water-passing conical hole and clean the inner wall of the water-passing conical hole.

9. The method for treating wastewater generated during cell culture medium processing according to claim 8, characterized in that, The inner wall of the electrocoagulation device below the anode plate is provided with a horizontal circular track and several vertical tracks. The several vertical tracks are evenly arranged along the circumference of the inner wall of the electrocoagulation device. A slider is locked in each vertical track. The outer side of the circular frame is connected to all the sliders, so that the cleaning plate can move up and down along the vertical tracks. At this time, the cleaning cone on the cleaning plate corresponds one-to-one with the position of the water-passing cone hole on the lower surface of the anode plate. The top of the vertical track is close to the lower surface of the anode plate. The horizontal circular track is set horizontally and runs around the circumference of the inner wall of the electrocoagulation device. Each vertical track passes through and connects to the horizontal circular track in its respective vertical direction. The distance between the horizontal circular track and the lower surface of the anode plate is less than the height of the cleaning cone.

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