Modular device for treating phenolic ammonia wastewater by optoelectronically enhanced bacterium-algae electrochemical system and method for treating phenolic ammonia wastewater by using the modular device

Abstract

Modular device for treating phenolic ammonia wastewater by photo - electrochemically enhanced bacteria - algae electrochemical system and method for treating phenolic ammonia wastewater by using the modular device, which relate to the technical field of sewage treatment. The present invention combines microorganism and electrochemical technologies, and efficiently removes phenols and ammonia nitrogen in wastewater through a bacteria - algae symbiotic system, achieving a synergistic effect and improving the treatment effect. Compared with traditional anaerobic treatment of coal chemical wastewater, the ammonia nitrogen in the effluent usually increases, while after being treated by the device of the present invention, the ammonia nitrogen is greatly reduced on the premise of ensuring the phenol removal rate, breaking through the limitations of traditional anaerobic treatment of the combined inhibition of phenol and ammonia, and realizing the synergistic and efficient removal of phenol and ammonia. The present invention can obtain a modular device for treating phenolic ammonia wastewater by photo - electrochemically enhanced bacteria - algae electrochemical system and a method for treating phenolic ammonia wastewater by using the modular device.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a modular device for treating phenol-ammonia wastewater by a photoelectrically enhanced bacteria-algae electrochemical system and a method for treating phenol-ammonia wastewater by using the modular device. Background Art

[0002] The traditional coal chemical wastewater treatment process is based on biotechnology and mainly relies on the redox reaction of bacteria to degrade phenol and ammonia pollutants. It has the inherent defect of "using energy to consume energy and transferring pollution", that is, it needs to consume a lot of energy to convert pollutants such as phenol and ammonia into CO2 and N2, etc. Phenol and ammonia in the wastewater are not fully utilized as important carbon and nitrogen resources. At the same time, the sludge produced becomes toxic and harmful hazardous waste, which still needs further high-cost treatment. How to turn these energy-containing carbon and nitrogen pollutants into resources and energy has become an increasingly urgent practical need.

[0003] The bacteria-algae symbiotic technology has the unique advantages of simultaneously removing organic matter and ammonia nitrogen, strengthening the treatment of phenol-ammonia wastewater, and recovering organisms. However, the single bacteria-algae system has poor shock resistance and is inhibited by the combined toxicity of phenol and ammonia. Toxic organic matter such as phenols will inhibit the growth of microalgae and limit the recovery of microalgae biomass. High concentrations of ammonia nitrogen will also inhibit bacterial metabolic performance. In recent years, bacteria-algae biofuel cells have achieved the metabolic advantages of bacteria and algae by relieving the combined inhibition of phenol and ammonia, providing a new idea for the efficient treatment and resource utilization of coal chemical wastewater. Summary of the invention

[0004] The purpose of the present invention is to solve the following technical problems and to provide a modular device for treating phenol-ammonia wastewater by a photoelectrically enhanced bacteria-algae electrochemical system and a method for treating phenol-ammonia wastewater by using the modular device.

[0005] (1) The current coal chemical wastewater treatment process usually treats phenol-ammonia wastewater in the manner of "energy consumption and pollution transfer";

[0006] (2) The current problem of high concentrations of phenol and ammonia pollutants coexisting, antagonizing, and being difficult to remove simultaneously in coal chemical wastewater.

[0007] A modular device for treating phenol-ammonia wastewater by a photoelectrically enhanced bacteria-algae electrochemical system, comprising a bacteria-algae electrochemical device and a solar-assisted photoelectric compensation device, wherein the bacteria-algae electrochemical device comprises a bacteria-algae primary battery device, a physical adsorption device and an internal reflux control device; and the solar-assisted photoelectric compensation device comprises an electrolytic cell device and a light compensation device.

[0008] The described bacteria-algae primary battery device includes an anode chamber 3, a buffer chamber 6, a cathode chamber 8, an anode carbon brush 12, and a cathode carbon brush 14; on one side of the anode chamber 3, there is an anode chamber water inlet 2, and inside the anode chamber 3, there are several anode carbon brushes 12, and anaerobic sludge 11 is attached to the anode carbon brushes 12; the anode chamber 3 is communicated with the buffer chamber 6 through a buffer chamber water inlet 5, the buffer chamber 6 is communicated with the cathode chamber 8 through a cathode chamber water inlet 7, and on one side of the cathode chamber 8, there is an overflow pipe 10; inside the cathode chamber 8, there are several cathode carbon brushes 14, and Synechocystis 13 is attached to the cathode carbon brushes 14;

[0009] The described physical adsorption device includes an activated carbon adsorption layer 4 and a zeolite adsorption layer 9; the activated carbon adsorption layer 4 is arranged at the bottoms of the anode chamber 3 and the buffer chamber 6, and the zeolite adsorption layer 9 is arranged at the bottom of the cathode chamber 8;

[0010] The described internal reflux control device includes a reflux pipe 15, a phenol concentration sensor a 21, a phenol concentration sensor b 22, and a motor drive device 30; the water inlet of the reflux pipe 15 is arranged inside the buffer chamber 6, the water outlet of the reflux pipe 15 is arranged on the water inlet pipe 1 at the anode chamber water inlet 2, a water inlet pump 31 is arranged on the water inlet pipe 1, and a reflux pump 32 is arranged on the reflux pipe 15; the phenol concentration sensor a 21 is arranged at the anode chamber water inlet 2, and the phenol concentration sensor b 22 is arranged at the buffer chamber water inlet 5; the motor drive device 30 is electrically connected to the water inlet pump 31 and the reflux pump 32 respectively;

[0011] The described electrolytic cell device includes a photovoltaic panel 16, a solar charging management device 17, and a relay a 18. The photovoltaic panel 16 and the solar charging management device 17 are both arranged above the anode chamber 3 and the buffer chamber 6. The photovoltaic panel 16 is electrically connected to the solar charging management device 17. The voltage output terminal of the solar charging management device 17 is electrically connected to the relay a 18. The common terminal of the relay a 18 is electrically connected to the anode carbon brush 12, and the normally closed terminal of the relay a 18 is electrically connected to the cathode carbon brush 14 to form a primary battery circuit. The normally open terminal of the relay a 18 is electrically connected to the cathode carbon brush 14 to form an electrolytic cell circuit;

[0012] The described light compensation device includes a relay b 19 and an LED lamp tube 20. The voltage output terminal of the solar charging management device 17 is electrically connected to the LED lamp tube 20 through the relay b 19.

[0013] A method for treating phenolic ammonia wastewater by using a modular device of a photo-electric enhanced bacteria-algae electrochemical system to treat phenolic ammonia wastewater is carried out according to the following steps:

[0014] Step S1: The phenolic ammonia wastewater is injected into the anode chamber 3 through the inlet pump 31 via the anode chamber water inlet 2, then successively passes through the buffer chamber 6 and the cathode chamber 8, and finally flows out from the overflow pipe 10 of the cathode chamber 8, with a hydraulic retention time of 48 - 72 h.

[0015] Step S2: The phenol concentration sensor a21 set at the anode chamber water inlet 2 monitors the phenol concentration of the phenolic ammonia wastewater in real - time. The main control micro - controller 25 reads the monitoring result of the phenol concentration sensor a21 once per second and controls the switching of the working circuit of the relay a18 according to the average phenol concentration of the phenolic ammonia wastewater within 1 minute: When the average phenol concentration is within 900 mg / L, the primary battery circuit is adopted, that is, the normally - closed end of the relay a18 is electrically connected to the cathode carbon brush 14; when the average phenol concentration is higher than 1100 mg / L, the electrolytic cell circuit is adopted, that is, the normally - open end of the relay a18 is electrically connected to the cathode carbon brush 14.

[0016] Advantages of the present invention:

[0017] (1) Strong resistance to water quality and environmental changes: The present invention demonstrates the convenience of device modularization and the adaptability to water quality and the natural environment, mainly due to its advanced monitoring and feedback mechanism. By setting the phenol concentration sensor a at the total water inlet and the phenol concentration sensor b at the buffer outlet, the concentration of phenol in the water can be monitored in real - time. When the phenol concentration of the buffer outlet water exceeds 150 mg / L or 300 mg / L, the system will automatically adjust, return the high - concentration water to the total water inlet, and adjust the influent flow rate respectively at 1:0.5 (effluent of the inlet pump: effluent of the reflux pump) and 1:1 incoming water, so as to ensure that the phenol concentration of the effluent is lower than 50 mg / L, keeping the water quality during the treatment process within a controllable range. The system can automatically switch the working mode according to needs, adopt solar - assisted photoelectric compensation, realize the auxiliary light growth of Synechocystis on rainy days and the free - switching circuit of the primary battery / electrolytic cell to adapt to different environmental conditions. This mechanism with high automation and strong self - regulation ability enables the device to quickly respond to water quality changes, maintain the treatment efficiency, while reducing energy and resource waste, demonstrating its high - efficiency water quality and environmental adaptability.

[0018] (2) Breaking through the bottleneck of phenol - ammonia co - inhibition and reversing inhibition to promotion: In the process of coal chemical wastewater treatment, high - concentration phenols and ammonia nitrogen will cause combined inhibition to microorganisms. Phenols in the wastewater have a significant toxic effect on microalgae, and too high ammonia nitrogen concentration in the wastewater will seriously inhibit the metabolic activities of anaerobic bacteria, thus affecting their ability to degrade phenols. In the modular device of the present invention, the cathode uses a combination of microalgae and zeolite to effectively absorb ammonia nitrogen, and the anode area uses a combination of anaerobic sludge and activated carbon to degrade phenolic compounds. The present invention respectively utilizes the metabolic advantages of bacteria and algae, and relieves the phenol - ammonia combined inhibition by separating phenol - ammonia pollutants, thereby realizing the synergistic removal of phenol - ammonia pollutants in coal chemical wastewater.

[0019] (3) Realizing the synergistic and efficient removal of phenols and ammonia by means of electrochemically symbiotic bacteria and algae: The present invention combines microbial and electrochemical technologies, and efficiently removes phenols and ammonia nitrogen in wastewater through a bacteria-algae symbiotic system, achieving a synergistic effect and improving the treatment effect. Compared with the traditional anaerobic treatment of coal chemical wastewater, the ammonia nitrogen in the effluent usually increases. However, after being treated by the device of the present invention, the ammonia nitrogen is significantly reduced on the premise of ensuring the phenol removal rate, breaking through the limitations of the combined inhibition of phenols and ammonia in traditional anaerobic treatment, and realizing the synergistic and efficient removal of phenols and ammonia.

[0020] (4) Energy conversion and resource utilization of carbon and nitrogen pollutants: The present invention combines the respective advantages of bacteria and algae in metabolizing carbon and nitrogen. Phenol and ammonia pollutants are no longer limited to the traditional treatment and are finally directly discharged as CO2 and N2. The mineralization of phenolic pollutants into CO2 can promote the photosynthetic reaction of Synechocystis, and ammonia nitrogen can also be assimilated by Synechocystis to increase the algal biomass. While the present invention breaks through the combined inhibition of phenols and ammonia to achieve "reverse inhibition and conversion to promotion", it provides a new direction for collecting algal biomass and converting it into bioenergy.

[0021] The present invention can obtain a modular device for treating phenol-ammonia wastewater by an electro-optically enhanced bacteria-algae electrochemical system and a method for treating phenol-ammonia wastewater using the modular device. Description of the Drawings

[0022] Figure 1 The front view of the modular device for treating phenol-ammonia wastewater by the electro-optically enhanced bacteria-algae electrochemical system of the present invention is shown. 1 represents the water inlet pipe, 2 represents the anode cell water inlet, 3 represents the anode cell, 4 represents the activated carbon adsorption layer, 5 represents the buffer cell water inlet, 6 represents the buffer cell, 7 represents the cathode cell water inlet, 8 represents the cathode cell, 9 represents the zeolite adsorption layer, 10 represents the overflow pipe, 11 represents the anaerobic sludge, 12 represents the anode carbon brush, 13 represents Synechocystis, 14 represents the cathode carbon brush, 15 represents the reflux pipe, 16 represents the photovoltaic panel, 20 represents the LED lamp tube, 21 represents the phenol concentration sensor a, 22 represents the phenol concentration sensor b, and 33 represents the steel frame;

[0023] Figure 2 The left view of the modular device for treating phenol-ammonia wastewater by the electro-optically enhanced bacteria-algae electrochemical system of the present invention is shown. 1 represents the water inlet pipe, 3 represents the anode cell, 4 represents the activated carbon adsorption layer, 11 represents the anaerobic sludge, 12 represents the anode carbon brush, 15 represents the reflux pipe, 16 represents the photovoltaic panel, 17 represents the solar charging management device, and 33 represents the steel frame;

[0024] Figure 3Shows a top view of the modular device for treating phenolic ammonia wastewater by the photoelectric enhanced bacteria-algae electrochemical system of the present invention. 1 represents the water inlet pipe, 3 represents the anode chamber, 6 represents the buffer chamber, 8 represents the cathode chamber, 10 represents the overflow pipe, 12 represents the anode carbon brush, 14 represents the cathode carbon brush, 15 represents the reflux pipe, 16 represents the photovoltaic panel, 20 represents the LED lamp tube, and 33 represents the steel frame;

[0025] Figure 4 Shows the connection diagram of the modular device for treating phenolic ammonia wastewater by the photoelectric enhanced bacteria-algae electrochemical system of the present invention. 17 represents the solar charging management device, 18 represents relay a, 19 represents relay b, 20 represents the LED lamp tube, 21 represents the phenol concentration sensor a, 22 represents the phenol concentration sensor b, 23 represents the light sensor, 24 represents the Bluetooth device, 25 represents the main control microcontroller, 30 represents the motor drive device, 31 represents the inlet water pump, and 32 represents the reflux pump;

[0026] Figure 5 Shows the schematic diagram of treating phenolic ammonia wastewater by the present invention using the modular device. Specific implementation manner

[0027] Specific implementation manner one: The modular device for treating phenolic ammonia wastewater by the photoelectric enhanced bacteria-algae electrochemical system in this implementation manner includes a bacteria-algae electrochemical device and a solar-assisted photoelectric compensation device. The bacteria-algae electrochemical device includes a bacteria-algae primary battery device, a physical adsorption device, and an internal reflux control device; the solar-assisted photoelectric compensation device includes an electrolytic cell device and a light compensation device;

[0028] The bacteria-algae primary battery device includes an anode chamber 3, a buffer chamber 6, a cathode chamber 8, an anode carbon brush 12, and a cathode carbon brush 14; on one side of the anode chamber 3, there is an anode chamber water inlet 2, and several anode carbon brushes 12 are arranged in the anode chamber 3, and anaerobic sludge 11 is attached to the anode carbon brushes 12; the anode chamber 3 is communicated with the buffer chamber 6 through a buffer chamber water inlet 5, the buffer chamber 6 is communicated with the cathode chamber 8 through a cathode chamber water inlet 7, and an overflow pipe 10 is arranged on one side of the cathode chamber 8; several cathode carbon brushes 14 are arranged in the cathode chamber 8, and Synechocystis 13 is attached to the cathode carbon brushes 14;

[0029] The physical adsorption device includes an activated carbon adsorption layer 4 and a zeolite adsorption layer 9; the activated carbon adsorption layer 4 is arranged at the bottom of the anode chamber 3 and the buffer chamber 6, and the zeolite adsorption layer 9 is arranged at the bottom of the cathode chamber 8;

[0030] The described internal reflux control device includes a reflux pipe 15, a phenol concentration sensor a21, a phenol concentration sensor b22, and a motor drive device 30; the water inlet of the reflux pipe 15 is arranged in the buffer tank 6, the water outlet of the reflux pipe 15 is arranged on the water inlet pipe 1 at the anode tank water inlet 2, a water inlet pump 31 is arranged on the water inlet pipe 1, and a reflux pump 32 is arranged on the reflux pipe 15; the phenol concentration sensor a21 is arranged at the anode tank water inlet 2, and the phenol concentration sensor b22 is arranged at the buffer tank water inlet 5; the motor drive device 30 is electrically connected to the water inlet pump 31 and the reflux pump 32 respectively;

[0031] The described electrolytic cell device includes a photovoltaic panel 16, a solar charging management device 17, and a relay a18. The photovoltaic panel 16 and the solar charging management device 17 are both arranged above the anode tank 3 and the buffer tank 6. The photovoltaic panel 16 is electrically connected to the solar charging management device 17. The voltage output end of the solar charging management device 17 is electrically connected to the relay a18. The common end of the relay a18 is electrically connected to the anode carbon brush 12, and the normally closed end of the relay a18 is electrically connected to the cathode carbon brush 14 to form a primary battery circuit. The normally open end of the relay a18 is electrically connected to the cathode carbon brush 14 to form an electrolytic cell circuit;

[0032] The described light compensation device includes a relay b19 and an LED lamp tube 20. The voltage output end of the solar charging management device 17 is electrically connected to the LED lamp tube 20 through the relay b19.

[0033] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that the volume ratio of the anode tank 3, the buffer tank 6, and the cathode tank 8 is (1 - 1.5):(0.5 - 0.7):(0.8 - 1), and the inner wall of the buffer tank 6 selects a cation exchange membrane made of sulfonated polystyrene as the filling material.

[0034] Other steps are the same as those in Specific Embodiment 1.

[0035] Specific Embodiment 3: The difference between this embodiment and Specific Embodiment 1 or 2 is that the anode tank water inlet 2 is arranged on the upper side wall of the anode tank 3, the buffer tank water inlet 5 is arranged on the lower side wall of the buffer tank 6, the cathode tank water inlet 7 is arranged on the upper side wall of the cathode tank 8, and the overflow pipe 10 is arranged on the upper side wall.

[0036] Other steps are the same as those in Specific Embodiment 1 or 2.

[0037] Specific Embodiment 4: The difference between this embodiment and any one of Specific Embodiments 1 to 3 is that the anode carbon brush 12, the cathode carbon brush 14, the photovoltaic panel 16, and the LED lamp tube 20 are all arranged on the steel frame 33 above the anode tank 3 and the buffer tank 6.

[0038] The other steps are the same as those in the first to third specific embodiments.

[0039] Specific embodiment five: The difference between this embodiment and any one of the first to fourth specific embodiments is that the number of the anode carbon brushes 12 and the cathode carbon brushes 14 is 4 to 8.

[0040] The other steps are the same as those in the first to fourth specific embodiments.

[0041] Specific embodiment six: The difference between this embodiment and any one of the first to fifth specific embodiments is that the electrolytic cell device further includes a Bluetooth device 24 and a main control microcontroller 25;

[0042] The main control microcontroller 25 reads the world time through the Bluetooth device 24; the main control microcontroller 25 is electrically connected to the solar charging management device 17, the relay a 18, the phenol concentration sensor a 21, the phenol concentration sensor b 22, and the motor drive device 30.

[0043] The other steps are the same as those in the first to fifth specific embodiments.

[0044] Specific embodiment seven: The difference between this embodiment and any one of the first to sixth specific embodiments is that the light compensation device further includes a light sensor 23, and the main control microcontroller 25 is respectively electrically connected to the light sensor 23 and the relay b 19.

[0045] The other steps are the same as those in the first to sixth specific embodiments.

[0046] Specific embodiment eight: The difference between this embodiment and any one of the first to seventh specific embodiments is that the solar charging management device 17, the Bluetooth device 24, and the main control microcontroller 25 are all arranged on the back of the photovoltaic panel 16.

[0047] The other steps are the same as those in the first to seventh specific embodiments.

[0048] Specific embodiment nine: The method for treating phenol-ammonia wastewater by using the modular device of the photo-electro enhanced bacteria-algae electrochemical system to treat phenol-ammonia wastewater is carried out according to the following steps:

[0049] Step S1: The phenol-ammonia wastewater is injected into the anode chamber 3 through the anode chamber water inlet 2 by the inlet water pump 31, then sequentially passes through the buffer chamber 6 and the cathode chamber 8, and finally flows out from the overflow pipe 10 of the cathode chamber 8, and the hydraulic retention time is 48 to 72 h;

[0050] Step S2: The phenol concentration sensor a21 set at the inlet 2 of the anode chamber monitors the phenol concentration of the phenol-ammonia wastewater in real time. The main control microcontroller 25 reads the monitoring result of the phenol concentration sensor a21 once per second and controls the relay a18 to switch the working circuit according to the average phenol concentration of the phenol-ammonia wastewater within 1 minute: when the average phenol concentration is within 900 mg / L, the primary battery circuit is adopted, that is, the normally closed end of the relay a18 is electrically connected to the cathode carbon brush 14; when the average phenol concentration is higher than 1100 mg / L, the electrolytic cell circuit is adopted, that is, the normally open end of the relay a18 is electrically connected to the cathode carbon brush 14.

[0051] Specific Embodiment Ten: The difference between this embodiment and Specific Embodiment Nine is that when the phenol concentration sensor b22 detects that the phenol concentration in the buffer tank 6 is 150 - 300 mg / L, it feeds back an electronic signal to the main control microcontroller 25. The main control microcontroller 25 controls the reflux pump 32 to start, and the wastewater in the buffer tank 6 is refluxed to the anode chamber 3 through the water inlet pipe 1. At the same time, the rotation speed of the water inlet pump 31 is reduced to ensure that the flow ratio of the water outlet of the water inlet pump 31 to the water inlet of the reflux pump 32 is adjusted to (2 - 2.5):1 under the condition that the total water inlet flow remains unchanged;

[0052] When the phenol concentration of the effluent from the buffer tank 6 exceeds 300 mg / L, the rotation speed of the water inlet pump 31 is further reduced to ensure that the flow ratio of the water outlet of the water inlet pump 31 to the water inlet of the reflux pump 32 is adjusted to (1 - 1.5):1 under the condition that the total water inlet flow remains unchanged;

[0053] The main control microcontroller 25 reads the time through the Bluetooth device 24 connected to the PC device; when the time is between 6:00 - 18:00, the main control microcontroller 25 receives the light signal returned by the light sensor 23: if the natural light intensity ≥ 5100 Lx, the relay b19 is disconnected, and the natural light is used as the growth light source of the Synechocystis 13 in the cathode chamber 8; if the natural light intensity is lower than 4900 Lx, the main control microcontroller 25 issues a light compensation instruction to control the relay b19 to close, and the solar charging management device 17 provides a stable voltage to the LED lamp tube 20.

[0054] Other steps are the same as those in Specific Embodiment Nine.

[0055] The following examples are used to verify the beneficial effects of the present invention:

[0056] Example 1: A modular device for treating phenol-ammonia wastewater by a photo-electric enhanced bacteria-algae electrochemical system, which is a vertical flow folded type and semi-buried electro-chemical bio-retention pond, including a bacteria-algae electrochemical device and a solar-assisted photo-electric compensation device. The bacteria-algae electrochemical device includes a bacteria-algae primary battery device, a physical adsorption device, and an internal reflux control device; the solar-assisted photo-electric compensation device includes an electrolytic cell device and a light compensation device;

[0057] The described bacteria-algae primary battery device includes an anode chamber 3, a buffer chamber 6, a cathode chamber 8, an anode carbon brush 12, and a cathode carbon brush 14; an anode chamber water inlet 2 is provided on one side of the anode chamber 3, and a number of anode carbon brushes 12 are arranged in the anode chamber 3. Anaerobic sludge 11 is attached to the anode carbon brushes 12 to form a biofilm; the anode chamber 3 is communicated with the buffer chamber 6 through a buffer chamber water inlet 5, the buffer chamber 6 is communicated with the cathode chamber 8 through a cathode chamber water inlet 7, and an overflow pipe 10 (DN = 100 mm) is provided on one side of the cathode chamber 8; a number of cathode carbon brushes 14 are arranged in the cathode chamber 8, and Synechocystis 13 is attached to the cathode carbon brushes 14 to form a biofilm; the Synechocystis 13 is an ordinary commercially available product;

[0058] The described physical adsorption device includes an activated carbon adsorption layer 4 and a zeolite adsorption layer 9; the activated carbon adsorption layer 4 is laid at the bottoms of the anode chamber 3 and the buffer chamber 6, and the laying thickness is 0.30 m; the zeolite adsorption layer 9 is laid at the bottom of the cathode chamber 8, and the laying thickness is 0.30 m;

[0059] The described internal reflux control device includes a reflux pipe 15 (DN = 50 mm), a phenol concentration sensor a 21, a phenol concentration sensor b 22, and a motor drive device 30; the water inlet of the reflux pipe 15 is arranged in the buffer chamber 6, the water outlet of the reflux pipe 15 is arranged on a water inlet pipe 1 (DN = 100 mm) at the anode chamber water inlet 2, a water inlet pump 31 is arranged on the water inlet pipe 1, and a reflux pump 32 is arranged on the reflux pipe 15; the phenol concentration sensor a 21 is arranged at the anode chamber water inlet 2, and the phenol concentration sensor b 22 is arranged at the buffer chamber water inlet 5; the motor drive device 30 is electrically connected to the water inlet pump 31 and the reflux pump 32 respectively;

[0060] The described electrolytic cell device includes a photovoltaic panel 16, a solar charging management device 17, and a relay a 18. The photovoltaic panel 16 and the solar charging management device 17 are both arranged above the anode chamber 3 and the buffer chamber 6. The photovoltaic panel 16 is electrically connected to the solar charging management device 17. The voltage output end of the solar charging management device 17 is electrically connected to the relay a 18. The common end of the relay a 18 is electrically connected to the anode carbon brush 12, and the normally closed end of the relay a 18 is electrically connected to the cathode carbon brush 14 to form a primary battery circuit, and the normally open end of the relay a 18 is electrically connected to the cathode carbon brush 14 to form an electrolytic cell circuit;

[0061] The described light compensation device includes a relay b 19 and LED lamp tubes 20 (the number of lamp tubes is selected as required). The voltage output end of the solar charging management device 17 is electrically connected to the LED lamp tubes 20 through the relay b 19.

[0062] The volume ratio of the anode cell 3, the buffer cell 6 and the cathode cell 8 is 1:0.7:0.8. The inner wall of the buffer cell 6 is filled with a cation exchange membrane made of sulfonated polystyrene. When the reflux system is started and the anode cell 3 and the cathode cell 8 are hydraulically disconnected, ammonium ions can migrate through the cation exchange membrane of the buffer cell 6.

[0063] The anode cell water inlet 2 is arranged on the upper side wall of the anode cell 3, the buffer cell water inlet 5 is arranged on the lower side wall of the buffer cell 6, the cathode cell water inlet 7 is arranged on the upper side wall of the cathode cell 8, and the overflow pipe 10 is arranged on the upper side wall.

[0064] The anode carbon brush 12, the cathode carbon brush 14, the photovoltaic panel 16, and the LED lamp tube 20 are all arranged on the steel frame 33 above the anode cell 3 and the buffer cell 6.

[0065] The number of both the anode carbon brush 12 and the cathode carbon brush 14 is 4.

[0066] The electrolytic cell device further includes a Bluetooth device 24 and a main control microcontroller (MCU) 25;

[0067] The main control microcontroller 25 reads the world time through the Bluetooth device 24; the main control microcontroller 25 is electrically connected to the solar charging management device 17, the relay a 18, the phenol concentration sensor a 21, the phenol concentration sensor b 22, and the motor drive device 30.

[0068] The main control microcontroller 25 is purchased from Guangzhou Xingyi Electronic Technology Co., Ltd. (Zhengdian Yuanzi), and the model is STM32F407ZGT6.

[0069] The light compensation device further includes a light sensor 23, and the main control microcontroller 25 is respectively electrically connected to the light sensor 23 and the relay b 19.

[0070] The solar charging management device 17, the Bluetooth device 24, and the main control microcontroller 25 are all arranged on the back of the photovoltaic panel 16.

[0071] Example 2: A method for treating phenolic ammonia wastewater by using the modular device of the photo-electric enhanced bacteria-algae electrochemical system described in Example 1 is carried out according to the following steps:

[0072] Step S1: Inject the phenolic ammonia wastewater into the anode cell 3 through the anode cell water inlet 2 by the inlet pump 31, then pass through the buffer cell 6 and the cathode cell 8 in sequence, and finally flow out from the overflow pipe 10 of the cathode cell 8, and the hydraulic retention time is 48 h;

[0073] Step S2: The phenol concentration sensor a21 set at the inlet 2 of the anode chamber monitors the phenol concentration of the phenol-ammonia wastewater in real time. The main control microcontroller 25 reads the monitoring result of the phenol concentration sensor a21 once per second and controls the relay a18 to switch the working circuit of the device according to the average phenol concentration of the phenol-ammonia wastewater within 1 minute: when the average phenol concentration is within 900 mg / L, the primary battery circuit is adopted, that is, the normally closed terminal of the relay a18 is electrically connected to the cathode carbon brush 14; when the average phenol concentration is higher than 1100 mg / L, the electrolytic cell circuit is adopted, that is, the normally open terminal of the relay a18 is electrically connected to the cathode carbon brush 14.

[0074] When the primary battery circuit is adopted, the phenol pollutants in the influent serve as electron donors and are degraded by the anaerobic sludge biofilm attached to the anode carbon brush 12 in the anode chamber 3; after the wastewater flows into the buffer tank 6, under the continuous adsorption of the activated carbon adsorption layer 4, the concentration of phenol pollutants gradually decreases; when it flows into the cathode chamber 8, the Synechocystis 13 can also further degrade the phenol pollutants; the electrons generated by the phenol pollutants on the anode carbon brush 12 are transmitted to the cathode carbon brush 14 via the primary battery circuit, promoting the migration of ammonium ions through the cation exchange membrane made of sulfonated polystyrene towards the cathode, and the ammonium ions enriched in the cathode chamber 8 are assimilated and absorbed by the Synechocystis 13 attached to the cathode carbon brush 14. The ion exchange capacity of the cation exchange membrane is 0.9 - 1.1 meq / g, and the thickness is 50 - 200 μm; when the ammonium ion concentration is relatively high, the zeolite adsorption layer 9 can continuously adsorb ammonium ions, reduce the nitrogen load, and while ensuring the nitrogen removal rate of the cathode, maintain a sustainable nitrogen source supply for the cathode microalgae through adsorption - slow release.

[0075] When the electrolytic cell circuit is adopted, the lithium battery serves as the working power source to output a stable voltage for electrolytic treatment of the phenol-ammonia wastewater. The anode carbon brush 12 is connected to the positive electrode of the lithium battery to accelerate the oxidation and removal of phenol pollutants; the cathode carbon brush 14 is connected to the negative electrode of the lithium battery, and electrons flow from the negative electrode of the lithium battery to the cathode carbon brush 14, and the ammonium ions in the wastewater move towards the cathode chamber 8 to be enriched, which can promote the Synechocystis 13 to assimilate and absorb ammonium ions.

[0076] When the phenol concentration sensor b22 detects that the phenol concentration in the buffer tank 6 is 150 - 300 mg / L, it feeds back an electronic signal to the main control microcontroller 25. The main control microcontroller 25 controls the reflux pump 32 to start, and the wastewater in the buffer tank 6 is refluxed to the anode chamber 3 through the inlet pipe 1, and at the same time, the rotation speed of the inlet pump 31 is reduced to ensure that the flow ratio of the outlet water of the inlet pump 31 to the inlet water of the reflux pump 32 is adjusted to (2 - 2.5):1 under the condition that the total influent flow remains unchanged;

[0077] When the phenol concentration of the effluent from the buffer tank 6 exceeds 300 mg / L, the rotation speed of the inlet pump 31 is further reduced to ensure that the flow ratio of the outlet water of the inlet pump 31 to the inlet water of the reflux pump 32 is adjusted to (1 - 1.5):1 under the condition that the total influent flow remains unchanged;

[0078] The photovoltaic panel 16 converts solar energy into electrical energy and stores it in the lithium battery of the solar charging management device 17. Under the control of the main control microcontroller 25, the solar charging management device 17 provides adaptive voltage for each electronic component and the external circuit (the water pump is powered separately). The main control microcontroller 25 connects to the PC device through the Bluetooth device 24 to read the time; when the time is between 6:00 and 18:00, the main control microcontroller 25 receives the light signal returned by the light sensor 23: if the natural light intensity ≥ 5100 Lx, the relay b19 disconnects, and natural light is used as the growth light source of the Synechocystis 13 in the cathode chamber 8; if the natural light intensity is lower than 4900 Lx, the main control microcontroller 25 issues a light compensation instruction to control the relay b19 to close, and the solar charging management device 17 provides a stable voltage to the LED lamp tube 20.

[0079] The main control microcontroller 25 in the electrolytic cell device can regularly collect and process the signals of each electronic device, determine the operating state of the device, realize the communication between each system, and make adaptive feedback instructions in a timely manner according to the operating state of the device to optimize the operation of the device.

[0080] The photovoltaic panel 16 is a single crystal 50W, 12V solar panel, with dimensions: 670mm × 450mm. Under sunlight, the photovoltaic panel generates the photovoltaic effect, stimulates the flow of electrons, and outputs a DC voltage (0.9V) to the solar charging management device 17; existing research shows that a low-intensity external voltage (0.5 - 2V) can promote the removal of organic matter and nitrogen in wastewater, and the removal effect is the best at 0.9V, and the COD removal rate is 95.30 ± 2.25%, so the working voltage of 0.9V is adopted in this embodiment; the solar charging management device 17 is composed of a CN3791 chip and a lithium battery, and a solar charging management circuit of the system is built inside; the relay a18 is a single-pole double-throw; the relay b19 is a single-pole single-throw switch;

[0081] Optimization of environmental conditions and best treatment effects:

[0082] A small modular device is used to verify the performance of the photo-electro enhanced bacterium-algae electrochemical system for treating phenol-ammonia wastewater and further optimize the conditions. Two glass bottles are processed into an anode chamber and a cathode chamber. The effective volume of the electrode chamber is 400 mL, which is separated by a cation exchange membrane in the middle. Brush is used as the cathode and anode electrode materials, and is connected by a titanium wire with an external load of 1000 Ω. Anaerobic sludge and Synechocystis are added to the anode and cathode respectively, with a sludge concentration of 5000 mg / L and an algal concentration of 500 mg / L, and a magnetic stirrer is used for stirring.

[0083] A three-factor and three-level orthogonal experiment was designed (see Table 1), where the factors to be adjusted included light intensity, light duration, and temperature, to explore the effects of different environmental factors on the degradation performance of phenolic and ammonia pollutants by a photoelectrochemical enhanced bacterium-algae system. The experiment was conducted in a batch operation mode. Phenolic and ammonia wastewater was prepared with phenol and ammonium chloride, with an influent COD concentration of 800 mg / L and an ammonia nitrogen concentration of 100 mg / L. The wastewater entered the anodic chamber through the shaded anode, and the hydraulic retention time was 48 h. The experimental results are shown in Table 2.

[0084] Table 1 is the factor-level table of the orthogonal experiment;

[0085] Table 1

[0086]

[0087] Table 2 shows the orthogonal experimental design and experimental results;

[0088] Table 2

[0089]

[0090] Based on the data calculated by DPS, simplified regression equations for the removal efficiencies of COD and NH4 + -N were obtained in the equations, as shown in Eqs. (1) and (2).

[0091] Y1 = -4.22 + 68.92 + 17.72 - 15.58 (1);

[0092] Y2 = -30.8 + 48.1 + 19.5 - 24.0 - 11.9 - 4.4 + 6.2 (2);

[0093] Combined with Table 2, the order of the influence of environmental factors on the removal efficiencies of NH4 + -N and COD was light intensity (A) > light duration (C) > temperature (B). In addition, Eqs. (1) and (2) indicate that there is no significant interaction among these three factors on the removal efficiencies of NH4 + -N and COD. Light intensity, as the most influential factor, can be attributed to its effect on the open circuit potential (OCP). According to the Nernst equation, the OCP can be changed by any oxidation-reduction reaction in a chemical process. When the light intensity reaches 5000 Lx, more dissolved oxygen seems to be produced by the algae in the cathode, resulting in an increase in the OCP. This proves the positive correlation between light intensity and OCP within a specific range, and the OCP reaches its maximum value at 5000 Lx, and the optimal OCP promotes the electron transfer and the migration of substances in the anodic chamber.

[0094] Therefore, the optimal environmental conditions are a light intensity of 5000 Lx, a light duration of 16 h / d, and a temperature of 25 °C. Under these operating conditions, the photoelectric enhanced bacterium-algae electrochemical system has the strongest environmental adaptability, the ability to break through the combined inhibition of phenol and ammonia and finally achieve reverse inhibition and promote growth, and the best effect on the resource utilization of phenol and ammonia pollutants. This is reflected in the fact that the COD removal rate can reach 96.7%, and the assimilation removal rate of ammonia nitrogen can reach more than 20%, which is used to synthesize algal biomass resources.

Claims

1. A modular device for treating phenolic ammonia wastewater by a photo-electric enhanced bacteria-algae electrochemical system, characterized in that The modular device described above includes a bacteria-algae electrochemical device and a solar-assisted photovoltaic compensation device. The bacteria-algae electrochemical device includes a bacteria-algae primary battery device, a physical adsorption device, and an internal reflux control device. The solar-assisted photovoltaic compensation device includes an electrolytic cell device and a light compensation device. The bacteria-algae primary battery device includes an anode cell (3), a buffer cell (6), a cathode cell (8), an anode carbon brush (12), and a cathode carbon brush (14). An anode cell water inlet (2) is provided on one side of the anode cell (3). A number of anode carbon brushes (12) are arranged in the anode cell (3), and anaerobic sludge (11) is attached to the anode carbon brushes (12). The anode cell (3) is communicated with the buffer cell (6) through a buffer cell water inlet (5), the buffer cell (6) is communicated with the cathode cell (8) through a cathode cell water inlet (7), and an overflow pipe (10) is provided on one side of the cathode cell (8). A number of cathode carbon brushes (14) are arranged in the cathode cell (8), and Synechocystis (13) is attached to the cathode carbon brushes (14). The physical adsorption device includes an activated carbon adsorption layer (4) and a zeolite adsorption layer (9). The activated carbon adsorption layer (4) is arranged at the bottoms of the anode cell (3) and the buffer cell (6), and the zeolite adsorption layer (9) is arranged at the bottom of the cathode cell (8). The internal reflux control device includes a reflux pipe (15), a phenol concentration sensor a (21), a phenol concentration sensor b (22), and a motor drive device (30). The water inlet of the reflux pipe (15) is arranged in the buffer cell (6), the water outlet of the reflux pipe (15) is arranged on the water inlet pipe (1) at the anode cell water inlet (2), a water inlet pump (31) is arranged on the water inlet pipe (1), and a reflux pump (32) is arranged on the reflux pipe (15). The phenol concentration sensor a (21) is arranged at the anode cell water inlet (2), and the phenol concentration sensor b (22) is arranged at the buffer cell water inlet (5). The motor drive device (30) is electrically connected to the water inlet pump (31) and the reflux pump (32) respectively. The electrolytic cell device includes a photovoltaic panel (16), a solar charging management device (17), and a relay a (18). The photovoltaic panel (16) and the solar charging management device (17) are both arranged above the anode cell (3) and the buffer cell (6). The photovoltaic panel (16) is electrically connected to the solar charging management device (17). The voltage output end of the solar charging management device (17) is electrically connected to the relay a (18). The common end of the relay a (18) is electrically connected to the anode carbon brush (12), the normally closed end of the relay a (18) is electrically connected to the cathode carbon brush (14) to form a primary battery circuit, and the normally open end of the relay a (18) is electrically connected to the cathode carbon brush (14) to form an electrolytic cell circuit. The described electrolytic cell device further includes a Bluetooth device (24) and a main control microcontroller (25); the main control microcontroller (25) reads the world time through the Bluetooth device (24); the main control microcontroller (25) is electrically connected to the solar charging management device (17), relay a (18), phenol concentration sensor a (21), phenol concentration sensor b (22), and motor drive device (30). The described light compensation device includes a relay b (19) and an LED lamp tube (20), and the voltage output terminal of the solar charging management device (17) is electrically connected to the LED lamp tube (20) through the relay b (19).

2. The modular device for treating phenolic ammonia wastewater by the optoelectronically enhanced bacteria-algae electrochemical system according to claim 1, characterized in that The volume ratio of the anode cell (3), buffer cell (6), and cathode cell (8) is (1 - 1.5):(0.5 - 0.7):(0.8 - 1), and the inner wall of the buffer cell (6) is filled with a cation exchange membrane made of sulfonated polystyrene material.

3. The modular device for treating phenolic ammonia wastewater by the optoelectronically enhanced bacterium-algae electrochemical system according to claim 1, characterized in that The anode cell water inlet (2) is arranged on the upper side wall of the anode cell (3), the buffer cell water inlet (5) is arranged on the lower side wall of the buffer cell (6), the cathode cell water inlet (7) is arranged on the upper side wall of the cathode cell (8), and the overflow pipe (10) is arranged on the upper side wall.

4. The modular device for treating phenolic ammonia wastewater by the optoelectronically enhanced bacteria-algae electrochemical system according to claim 1, characterized in that The anode carbon brush (12), cathode carbon brush (14), photovoltaic panel (16), and LED lamp tube (20) are all arranged on the steel frame (33) above the anode cell (3) and buffer cell (6).

5. The modular device for treating phenolic ammonia wastewater by the optoelectronically enhanced bacteria-algae electrochemical system according to claim 1, characterized in that The number of both the anode carbon brush (12) and the cathode carbon brush (14) is 4 - 8.

6. The modular device for treating phenolic ammonia wastewater by the optoelectronic enhanced bacteria-algae electrochemical system according to claim 1, characterized in that The described light compensation device further includes a light sensor (23), and the main control microcontroller (25) is electrically connected to the light sensor (23) and the relay b (19) respectively.

7. The modular device for treating phenolic ammonia wastewater by the optoelectronically enhanced bacterium-algae electrochemical system according to claim 1, characterized in that The solar charging management device (17), Bluetooth device (24), and main control microcontroller (25) are all arranged on the back of the photovoltaic panel (16).

8. A method for treating phenolic ammonia wastewater by using a modular device for treating phenolic ammonia wastewater with the photoelectric enhanced bacteria-algae electrochemical system according to any one of claims 1-7, characterized in that This method is carried out according to the following steps: Step S1: Inject the phenol - ammonia wastewater into the anode cell (3) through the anode cell water inlet (2) by the feed water pump (31), then pass through the buffer cell (6) and the cathode cell (8) in sequence, and finally flow out from the overflow pipe (10) of the cathode cell (8), with a hydraulic retention time of 48 - 72 h. Step S2: The phenol concentration sensor a (21) arranged at the anode cell water inlet (2) monitors the phenol concentration of the phenol - ammonia wastewater in real - time. The main control microcontroller (25) reads the monitoring result of the phenol concentration sensor a (21) once per second and controls the relay a (18) to switch the device working circuit according to the average phenol concentration of the phenol - ammonia wastewater within 1 minute: when the average phenol concentration is within 900 mg / L, the primary battery circuit is adopted, that is, the normally - closed end of the relay a (18) is electrically connected to the cathode carbon brush (14); when the average phenol concentration is higher than 1100 mg / L, the electrolytic cell circuit is adopted, that is, the normally - open end of the relay a (18) is electrically connected to the cathode carbon brush (14).

9. The method for treating phenolic ammonia wastewater by using the modular device for treating phenolic ammonia wastewater with a photoelectric enhanced bacteria-algae electrochemical system according to claim 8, characterized in that When the phenol concentration sensor b (22) detects that the phenol concentration in the buffer pool (6) is 150 - 300 mg / L, it feeds back an electronic signal to the main control microcontroller (25). The main control microcontroller (25) controls the reflux pump (32) to start, and the wastewater in the buffer pool (6) is refluxed into the anode pool (3) through the water inlet pipe (1). At the same time, the rotation speed of the water inlet pump (31) is reduced to ensure that the flow ratio of the water outlet of the water inlet pump (31) to the water inlet of the reflux pump (32) is adjusted to (2 - 2.5):1 under the condition of constant total influent flow rate. When the phenol concentration of the effluent from the buffer pool (6) exceeds 300 mg / L, the rotation speed of the water inlet pump (31) is further reduced to ensure that the flow ratio of the water outlet of the water inlet pump (31) to the water inlet of the reflux pump (32) is adjusted to (1 - 1.5):1 under the condition of constant total influent flow rate. The main control microcontroller (25) connects to a PC device through the Bluetooth device (24) to read the time. When the time is between 6:00 - 18:00, the main control microcontroller (25) receives the light signal returned by the light sensor (23): If the natural light intensity ≥ 5000 Lx, the relay b (19) is disconnected, and natural light is used as the growth light source of the Synechocystis (13) in the cathode pool (8); If the natural light intensity is lower than 5000 Lx, the main control microcontroller (25) issues a light compensation instruction to control the relay b (19) to close, and the solar charging management device (17) provides a stable voltage to the LED lamp tube (20).

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