A bioelectric Fenton component, a circulation well device and a system

Abstract

The present invention relates to a bio-electric Fenton component, a circulating well device and a system, which at least comprises an anode chamber, wherein the anode chamber comprises an anode and a cathode which are staggered from the inside and the outside; the electroactive microorganisms loaded on the surface of the anode conductive carrier particles degrade the organic carbon source in the anode liquid to produce protons and electrons; the cathode uses oxygen as an electron acceptor and combines with the protons transferred from the anode to generate H2O2, and Fe 3+ Generates Fe as electron acceptor 2+ , a Fenton-like reaction occurs on the cathode surface and degrades the organic pollutants in the cathode liquid, so that the anode liquid injected into the chamber of the electrode and the cathode liquid in the circulation well are purified at the same time. The present invention greatly reduces the impact of oxygen on the anaerobic environment of the anode chamber in the electrode while ensuring that the cathode uses oxygen as an electron acceptor through the staggered arrangement of the cathode and the anode in space. The constructed bioelectric Fenton system can accelerate the degradation of organic pollutants in the circulation well.

Description

[0001] Description of the case

[0002] The original basis of this divisional application is the patent application with application number 202210030249.1, application date January 11, 2022, and invention name “A dislocated electrode bioelectric Fenton circulation well system”. Technical Field

[0003] The present invention relates to the technical field of in-situ remediation of groundwater pollution, and in particular to a bioelectric Fenton component, a circulation well device and a system. Background Art

[0004] Groundwater circulation well technology is an in-situ remediation technology. Through the special design of the main well pipe and the aeration / injection driving effect, the groundwater in the aquifer is driven to flow, so that the groundwater forms a vertical three-dimensional water flow cycle within a certain space range of the aquifer around the circulation well. It has a wide range of applications in the remediation of organic contaminated groundwater. The circulation well technology has the advantages of simple principle, low pollution remediation cost, easy equipment operation and maintenance, and little disturbance to the aquifer. At the same time, it can also couple with multiphase extraction, in-situ aeration, microbial remediation and chemical oxidation and other pollution remediation technologies. It has huge development potential and broad application prospects in the field of groundwater organic pollution remediation.

[0005] Early circulating well technology mainly achieved in-situ remediation of organically contaminated groundwater through two methods: steam stripping in the well and enhanced biodegradation. First, through the continuous scouring and disturbance of three-dimensional water circulation, organic matter in the aquifer was driven into the well, and aeration in the well blew away volatile and semi-volatile organic pollutants in the groundwater from the water phase into the gas phase; second, aeration increased the dissolved oxygen content in the groundwater and diffused it into the circulation well influence area with the flow of groundwater, thereby enhancing the in-situ aerobic biodegradation. Therefore, the circulating well technology has a good remediation effect on groundwater pollution dominated by volatile organic matter, and the degradation of non-volatile organic matter depends on factors such as the presence of indigenous microorganisms and their pollutant degradation performance. For organic pollutants in groundwater that are difficult to biodegrade, it is necessary to couple other pollution remediation technologies to achieve the removal of pollutants. A single circulating well technology is difficult to achieve an ideal remediation effect.

[0006] Bio-electro-Fenton technology is a new type of wastewater treatment technology developed on the basis of bio-electrochemical technology. It couples bio-electrochemical technology with electro-Fenton technology to produce H2O2 in situ at the cathode and combine with Fe 2+ The Fenton reaction produces highly oxidizing free radicals, which can efficiently oxidize and degrade organic pollutants. Due to the extracellular electron transfer of electroactive microorganisms at the anode, the bio-electro-Fenton technology has the characteristics of low energy consumption, low cost, high pollutant degradation efficiency, and low selectivity, making it very suitable for the remediation of groundwater with multiple types of complex pollution in actual sites.

[0007] At present, there is no report on the combined application of bio-electric Fenton technology and circulating well technology. Based on their own characteristics, combining them can achieve in-situ continuous and efficient remediation of organic contaminated groundwater, but there are still many challenges, such as: the coupling form of proton exchange membranes, the anaerobic environment required for the growth of electroactive microorganisms, the method of adding iron sources, etc. The present invention is committed to solving the above technical problems and provides a circulating well system for in-situ remediation of organic contaminated groundwater.

[0008] At present, there are few technical solutions for in-situ remediation of groundwater using bioelectric Fenton technology, and injection remediation is generally used to remediate groundwater. For example, patent document CN 102515343 B discloses an expandable gas barrier device and its injection remediation method for groundwater pollution, the device includes a main gas injection pipe, the middle part of which is covered with a rubber cylinder assembly made of elastic material; the main gas injection pipe is symmetrically covered with a group of rubber cylinder joints, protective sleeves, intermediate joints, and connecting sleeves on the upper and lower parts of the rubber cylinder assembly. The connecting sleeve I is connected between the intermediate joint I and the upper joint; the upper joint is provided with an upper interface for connecting the main gas injection pipe with the external gas injection pipe, and an inflation interface is provided next to the upper interface, the upper end of the inflation interface is connected to the external inflation pipe, and the lower end of the inflation interface extends downward to communicate with the gas injection cavity. Although this invention can ensure rapid, one-way gas injection in the air injection well, and can meet the needs of large-scale in-situ air injection technology for the remediation of groundwater in sites contaminated by volatile organic compounds, it cannot form a vertical three-dimensional circulation of groundwater, has poor applicability to heterogeneous formations, and cannot achieve synchronous purification of organic pollutants coexisting in different phases. Different phases refer to organic pollutants in dissolved phase, free phase, gas phase, and residual phase.

[0009] For example, patent document CN 210598814U discloses an integrated drilling rig for soil and groundwater sampling and repair, including a power head component, the power head component includes an impact rotary power head and a rotary jet power head, the impact rotary power head and the rotary jet power head are installed side by side in the sliding track of the top carriage of the carriage component, the top carriage is connected to the bottom carriage through an oil cylinder, one end of the oil cylinder is fixed to the bottom carriage by a pin shaft and a cotter pin, and the other end is locked with a nut through a protruding piston head, the carriage component also includes a first wear-resistant plate and a second wear-resistant plate, the first wear-resistant plate and the second wear-resistant plate are fixed to the upper and lower ends of the bottom carriage by bolts, and have a certain interval to form the sliding track of the top carriage, and the carriage component is installed on the detection frame. However, this patent can only repair groundwater, and cannot achieve synchronous purification of organic pollutants coexisting in different phases.

[0010] Patent document CN 206955867 U also discloses a circulation well device for in-situ remediation of organically contaminated groundwater, including a circulation well, an aeration system, a biological treatment system and a reagent dosing system; the circulation well is divided into an inner well and an outer well; the inner well and the outer well are divided into upper and lower sections, separated by a partition in the middle; the aeration system includes an air pump, an air delivery pipe and an aeration head; the biological treatment system includes a microbial filling area, a submersible pump, a water pump and a spray head; the reagent dosing system includes a repair reagent storage container, a dosing pump, a reagent delivery pipe, a reagent dosing pipe and a reagent addition pipe. However, the microorganisms in this invention have a small load space, a high selectivity for pollutants, are greatly affected by the biological toxicity of pollutants, and have a low remediation efficiency.

[0011] Patent document CN 112551681 A also discloses a single-chamber microbial electro-Fenton assembly and its application, including: an anode, a cathode, and an electrolyte; the anode and the cathode are arranged in the same single chamber; the anode includes: an anode substrate formed by rolling multiple layers of carbon cloth and a plastic mesh, the plastic mesh is arranged between the carbon cloths to separate the carbon cloths; the anode substrate is loaded with mixed bacteria; the mixed bacteria are composed of Rhodopseudomonas palustris, Proteus vulgaris, Bacillus toyonensis, and Pacific Alkanophage; the cathode includes: a bracket made of titanium mesh, the inside of the bracket is filled with activated carbon powder loaded with graphene and cobalt; the electrolyte includes sewage to be treated and added nutrients; the mixed bacteria decomposes organic matter in the sewage to be treated to generate electrons for the cathode to use. However, since the anode and the cathode in this patent are both arranged in the sewage, the O2 near the cathode has a greater impact on the reaction activity of the microorganisms loaded on the anode surface.

[0012] Patent document CN109179860A also discloses a method for synchronous catalytic oxidation of difficult-to-degrade pollutants in secondary effluent and degradation of excess sludge. It relates to a method for catalytic oxidation treatment of secondary tail water and degradation of excess sludge. It aims to solve the problems of high cost and low resource utilization rate of treatment of difficult-to-degrade pollutants and excess sludge in existing water. This method: 1. Establish a bioelectrochemical coupled electro-Fenton reaction system; 2. Add nutrient solution and electron acceptor solution to the anode chamber and cathode chamber respectively, and inoculate excess sludge in the anode chamber, using a carbon brush containing iron oxide as a composite cathode; cultivate until the output voltage is stable and greater than 0.65V, and start successfully; 3. Add the excess sludge to be treated and the secondary effluent containing difficult-to-degrade pollutants to the anode chamber and cathode chamber respectively, and treat them synchronously. However, the electrodes of this patent are arranged side by side, and such an installation method cannot reduce the impact of cathode aeration on the anaerobic environment of the anode.

[0013] Patent document CN103022541A discloses a dual-chamber aeration nitrification microbial fuel cell with different strengths. A proton exchange membrane is provided between the anode chamber and the cathode chamber, the anode chamber is filled with anode liquid, and the anode chamber is divided into a first aeration zone and a first reaction zone by a first partition, and the first reaction zone is provided with a pre-filmed anode of nitrifying bacteria; the cathode chamber is filled with cathode liquid, and the cathode chamber is divided into a second aeration zone and a second reaction zone by a second partition, and the second reaction zone is provided with a Pt-loaded cathode; microporous aeration tubes are provided at the bottom of the first aeration zone and the second aeration zone, and a sealing cover and a wire fixing tube are provided at the top of the first aeration zone and the second aeration zone, and the sealing cover is sealed and connected with a silicone gasket and a flange.

[0014] In addition, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the applicant studied a large number of documents and patents when making the present invention, but due to space limitations, not all details and contents are listed in detail. However, this does not mean that the present invention does not have the characteristics of these prior arts. On the contrary, the present invention already has all the characteristics of the prior art, and the applicant reserves the right to add relevant prior art to the background technology. Summary of the invention

[0015] The circulating well used for groundwater in-situ remediation in the prior art mainly achieves the purification of contaminated groundwater by two methods: aeration in the well and enhanced in-situ biodegradation. The selectivity for pollutants is high, and the types of pollution that can be repaired are relatively limited. Only by coupling with other technologies can its ability to repair contaminated groundwater be enhanced. Bioelectric Fenton technology can efficiently degrade organic pollutants in water, with low selectivity and low energy consumption. Coupling the two may enable efficient and continuous in-situ remediation of organic contaminated groundwater. The present invention sets a unique electrode structure in the circulating well so that the cathode and the anode are spatially displaced, for example, the cathode and the anode are vertically displaced, and the anode and the cathode are displaced inside and outside the anode chamber to reduce the impact of oxygen on the anaerobic environment of the anode. The present invention also reduces the impact of oxygen on the anaerobic environment of the anode by changing the position of the aeration head of the aeration system, setting the aeration head at the junction of the cathode and the anode, and the direction of the aeration head is toward the cathode. The present invention also injects anode liquid composed of organic wastewater into the anode chamber, so that the electroactive microorganisms of the anode can simultaneously degrade the organic wastewater, thereby achieving synchronous purification of organic wastewater and organic contaminated groundwater.

[0016] In view of the deficiencies in the prior art, the present invention provides a bioelectric Fenton component, a circulation well device and a system, which at least include a circulation well, a water pumping and injection component and a bioelectric Fenton component, wherein the water pumping and injection component is used to realize water pumping and injection between different screen sections of the circulation well, and the bioelectric Fenton component arranged in the first screen section of the circulation well includes at least a plurality of electrodes arranged in a staggered manner, wherein a plurality of cathodes and a plurality of anodes of the electrodes are spatially displaced in a manner different from their distribution areas, and / or the cathodes of the electrodes are arranged outside a chamber coated with a proton exchange membrane, and the anodes are arranged inside a chamber coated with a proton exchange membrane, and the cathodes and the anodes are staggered in the axial direction of the electrodes.

[0017] The present invention separates the cathode distribution area from the anode distribution area by spatially dislocating the cathode and the anode, thereby facilitating targeted aeration in different areas and reducing the impact of aeration on the anaerobic environment of the anode.

[0018] The electrodes in the prior art are distributed in the groundwater. When the cathode is aerated, the anode will also be affected by the aerated oxygen, which reduces the degradation efficiency of the anode on organic matter in the groundwater. In view of this defect, the electrode of the present invention is provided with at least one chamber coated with a proton exchange membrane to form an anode chamber for injecting anolyte, and the first part of the anode chamber belonging to the anode section is filled with conductive carrier particles loaded with electroactive microorganisms to form an anode, and the outer surface of the second part of the anode chamber belonging to the cathode section is coated with iron-modified carbon felt to form a cathode, so that the anode and the cathode are staggered inside and outside the anode chamber. The present invention arranges the cathode and the anode staggered inside and outside the anode chamber so that the anode is away from the cathode. When the cathode receives oxygen, the electroactive microorganisms in the anode are in an anaerobic environment in the anode chamber and are not directly in contact with oxygen. At the same time, the electroactive microorganisms can decompose the organic pollutants in the anode liquid, thereby achieving the technical effect of purifying the anode liquid and the cathode liquid at the same time. The conductive carrier particle anode of the present invention has a large surface area, which gives the electroactive microorganisms more load space, and the cathode formed by the iron-modified carbon felt greatly reduces the Fenton-like reaction of the external Fe 2+ There may be a risk of secondary groundwater contamination.

[0019] Since the anode and cathode of the electrode of the present invention are arranged and distributed in the staggered area, that is, the cathode distribution area and the anode distribution area only have a boundary, and there is no intersection of the distribution areas, the present invention can aerate the cathode distribution area, thereby reducing the impact of aeration on the electroactive microorganisms of the anode. Preferably, the circulation well system also includes an aeration system, and the aeration head of the aeration system is arranged at the junction of the anode and the cathode, and the aeration head is arranged in a manner of aerating toward the position of the cathode to reduce the impact of oxygen on the anaerobic environment of the anode chamber.

[0020] In view of the limitation that the existing groundwater circulation well technology can only repair groundwater, the present invention deoxidizes the anolyte and then degrades it at the anode. Specifically, the anolyte is organic wastewater that has been deoxygenated by the deoxygenation system, so that the electroactive microorganisms carried on the surface of the conductive carrier particles filled in the anode section in the anode chamber grow in an anaerobic environment. After the anolyte is deoxygenated, the degradation ability of the electroactive microorganisms carried on the surface of the conductive carrier particles is stronger, so that the organic wastewater discharged by the multiphase extraction unit or other production processes, namely the anolyte, can also be degraded, thereby achieving simultaneous purification of surface organic wastewater and groundwater. Preferably, when power is turned on, the electroactive microorganisms carried on the surface of the conductive carrier particles in the anode degrade the organic carbon source in the anolyte to produce protons and electrons, and the cathode uses oxygen as an electron acceptor and combines with the protons transferred from the anode to generate H2O2, and Fe 3+ Generates Fe as electron acceptor 2+ A Fenton-like reaction occurs on the cathode surface and degrades organic pollutants in the cathode liquid, so that the anode liquid injected into the chamber of the electrode and the cathode liquid in the circulation well are purified at the same time; wherein the anode liquid is organic wastewater and the cathode liquid is organically contaminated groundwater.

[0021] Preferably, several electrodes are arranged in parallel, and the horizontal position where the center of the cathode is located is higher than the horizontal position where the center of the anode is located. The parallel arrangement of electrodes is conducive to the cathode and anode being distributed in different areas. The cathode is arranged at a higher position, and the anode is arranged at a lower position. The anolyte is injected into the position where the anode is located at the bottom of the chamber by an injection pump, flows from bottom to top in the chamber, and is extracted at the position where the cathode is located at the top of the chamber, which reduces the extraction difficulty of the extraction pump, thereby reducing the energy consumption of the extraction pump. At the same time, the flow of the anolyte from bottom to top is conducive to the transfer of protons generated by the anode reaction to the cathode through the proton exchange membrane, reducing the mass transfer resistance.

[0022] Preferably, a plurality of the electrodes are arranged vertically in parallel, and the cathode is located at the top of the anode. The electrodes are arranged vertically, and the cathode is higher than the anode, which is conducive to shortening the path of the anolyte flowing into the anode chamber. During aeration, the bubbles move upward, and the cathode is at a high position, which is conducive to the cathode receiving oxygen quickly, and is also conducive to reducing the possibility of the anode contacting oxygen.

[0023] Preferably, the anolyte is injected into the anode chamber from the anode end of the electrode, and the reacted anolyte is extracted from the cathode end of the electrode. The injection and extraction of the anolyte allows the purified anolyte to be quickly discharged, and the injection of new anolyte allows the anolyte to continue to react and degrade.

[0024] Preferably, the anode chamber in the electrode is composed of a tube whose outer surface is coated with a proton exchange membrane, wherein the tube wall is provided with a plurality of holes penetrating the tube wall, providing an effective channel for the protons in the anode chamber to transfer to the cathode through the proton exchange membrane, thereby reducing the mass transfer resistance.

[0025] The present invention also provides a bioelectric Fenton assembly for purifying anolyte and cathode liquid at the same time, comprising at least a plurality of electrodes arranged in a staggered manner, wherein at least one chamber covered by a proton exchange membrane is arranged in the electrode to form an anode chamber for injecting anolyte, wherein the first part of the anode chamber belonging to the anode section is filled with conductive carrier particles to form an anode, and the outer surface of the second part of the anode chamber belonging to the cathode section is covered with iron-modified carbon felt to form a cathode, so that the anode and the cathode are arranged in a staggered manner inside and outside the anode chamber; the cathode and the anode of the electrode are arranged at different horizontal heights so that the anode and the cathode are arranged in a staggered manner in the vertical direction. The bioelectric Fenton assembly of the present invention separates the cathode distribution area from the anode distribution area by spatially staggering the cathode and the anode, and an aeration system is arranged to blow only toward the cathode, thereby reducing the impact of oxygen on the anaerobic environment of the anode and improving the degradation capacity of the electroactive microorganisms in the anode chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a simplified structural schematic diagram of a circulation well system in a working state according to a preferred embodiment of the present invention;

[0027] Figure 2 It is a simplified structural schematic diagram of a circulation well system according to a preferred embodiment of the present invention;

[0028] Figure 3 It is a simplified structural schematic diagram of the bioelectric Fenton component of the present invention;

[0029] Figure 4 is a simplified structural schematic diagram of the anode chamber of the electrode of the present invention;

[0030] Figure 5 It is a schematic diagram of the cross-sectional structure of the electrode of the present invention.

[0031] Reference numerals list

[0032] 100: circulation well; 1: well body; 2: first sieve hole; 3: second sieve hole; 4: packer; 5: pumping and injection assembly; 6: anode chamber; 7: cathode chamber; 8: proton exchange membrane; 9: aeration system; 10: power supply; 11: anode; 12: cathode; 13: pipe; 14: aeration head; 15: liquid storage tank; 16: first pump; 17: second pump; 18: deoxygenation system; 19: vacuum pump; 20: gas treatment device; 21: first sieve section; 22: second sieve section; 23: electroactive microorganisms. DETAILED DESCRIPTION

[0033] The following is a detailed description with reference to the accompanying drawings.

[0034] In view of the deficiencies in the prior art, the present invention provides a staggered electrode bioelectric Fenton circulation well system and also provides a bioelectric Fenton component for the circulation well.

[0035] In the present invention, the conductive carrier particles refer to particles that can conduct electricity and carry microorganisms, such as three-dimensional graphite particles and the like.

[0036] The electroactive microorganisms in the present invention are bacteria that can degrade organic carbon sources in organic wastewater and produce protons and electrons, such as cultured and domesticated Shewanella, Geobacter, and the like.

[0037] The well body 1 of the circulation well is divided into at least two parts, a first screen section 21 and a second screen section 22, by a packer 4. The position of the first screen section 21 is higher than that of the second screen section 22. The well wall of the first screen section 21 is provided with a first screen hole 2. The well wall of the second screen section 22 is provided with a second screen hole 3. Under the action of gravity, groundwater in the aquifer enters the second screen section 22 through the second screen hole 3. The pumping and injection assembly 5 is used to realize pumping and injection between different screen sections of the circulation well, for example, including a pumping and injection pump, a second pipeline that penetrates the packer 4 and extends to the second screen section 22, and a first pipeline that extends to the first screen section 21. The pumping and injection assembly 5 pumps out the groundwater in the second screen section 22 and injects it into the first screen section 21. The groundwater in the first screen section 21 then flows out through the first screen hole 2 to the groundwater aquifer outside the well, so that the groundwater forms a vertical three-dimensional water flow circulation inside and outside the well.

[0038] like Figure 1 and Figure 2 As shown, the bioelectric Fenton assembly of the present invention is arranged in the first screen section 21 of the circulation well 100. The bioelectric Fenton assembly can be one set or multiple sets. The bioelectric Fenton assembly can be arranged based on the size of the circulation well. Several bioelectric Fenton assemblies can be arranged in parallel.

[0039] The bioelectric Fenton assembly at least comprises a plurality of electrodes arranged in a staggered manner. The anode 11 and the cathode 12 are respectively connected to the positive and negative electrodes of an external DC power source 10 through wires.

[0040] The cathode 12 and the anode 11 of the electrode are arranged in a staggered manner. Figures 1 to 3 As shown, the electrode includes an anode 11 and a cathode 12. There is a junction between the anode 11 and the cathode 12. The cathodes 12 of several electrodes are arranged in the same direction, and the anodes 11 of several electrodes are arranged in the same direction, so that the anode 11 and the cathode 12 are distributed in two regions, and the anode 11 and the cathode 12 are staggered to form a staggered distribution.

[0041] Preferably, the cathode 12 of the electrode is arranged outside the chamber coated with the proton exchange membrane 8, the anode 11 is arranged inside the chamber coated with the proton exchange membrane, and the cathode 12 and the anode 11 are arranged in an offset manner in the axial direction of the electrode, so that the cathode 12 and the anode 11 form a spatial dislocation. For example, the anode 11 is arranged inside the chamber, and the cathode 12 is arranged on the surface of the proton exchange membrane outside the chamber. Due to the misalignment of the distribution area and the misalignment of the setting position of the anode 11 and the cathode 12, the anode 11 and the cathode 12 form a spatial dislocation.

[0042] The cathode 12 and the anode 11 require different reaction environments. The cathode 12 requires oxygen, while the anode 11 needs an anaerobic environment to degrade organic matter. When the anode 11 and the cathode 12 are spatially dislocated, the different distribution areas make the reaction of the anode 11 less affected by the oxygen in the environment of the cathode 12. This is conducive to the cathode and the anode to perform different degradation reactions respectively.

[0043] The electrode of the present invention includes at least one chamber. The chamber is formed by the proton exchange membrane 8 covering the surface of the tube 13. The number of chambers is not limited, and it can be one, or two or more. The shape of the chamber is not limited, and it can be spherical, cylindrical, prismatic, polygonal column, special-shaped chamber or irregular shape, etc. Preferably, the chamber is set to be cylindrical. Preferably, the tube 13 can be a stainless steel tube, or a resin tube, or a tube formed of other materials.

[0044] like Figure 4 and Figure 5 As shown, the tube wall of the tube 13 is provided with a plurality of holes penetrating the tube wall. The holes may be distributed in a regular arrangement or in an irregular arrangement. The holes are provided for protons to pass through the proton exchange membrane. The shape of the holes is not limited, and may be square, circular, triangular, polygonal or irregular. The proton exchange membrane 8 seals the holes and ends on the tube 13, i.e., the entire tube 13 is sealed.

[0045] The chamber formed by the tube 13 with the proton exchange membrane 8 on the outer surface is called the anode chamber 6. The space in the first screen section 21 where the chamber is located is called the cathode chamber 7. The organically contaminated groundwater flowing continuously in the cathode chamber 7 is the cathode liquid.

[0046] like Figure 4 and Figure 5 As shown, one end of the anode chamber 6 is filled with conductive carrier particles loaded with electroactive microorganisms 23 to form an anode 11. The anode 11 composed of the conductive carrier particles has a large surface area, which provides more loading space for the electroactive microorganisms 23, and the cathode composed of the iron-modified carbon felt greatly reduces the Fenton-like reaction of the added Fe 2+ There may be a risk of secondary groundwater contamination.

[0047] The first part of the anode chamber 6 filled with conductive carrier particles constitutes the anode section, and the second part not filled with conductive carrier particles constitutes the cathode section. The anode section of the anode chamber filled with conductive carrier particles is used to inject anolyte. The anolyte is deoxygenated organic wastewater. The organic wastewater can be a multiphase extraction separation liquid, or it can be produced and discharged by other processes in the factory. The anolyte penetrates the conductive carrier particles and contacts with the electroactive microorganisms. The anolyte is injected into the anode chamber from the anode end of the electrode, and the reacted anolyte is extracted from the cathode end of the electrode.

[0048] The outer surface of the proton exchange membrane 8 of the cathode section is coated with iron-modified carbon felt to form the cathode 12. The iron-modified carbon felt electrode is loaded with Fe 3+ The Fe fixed on the carbon felt surface 3+ Gaining electrons to generate Fe 2+ , participates in the Fenton reaction and forms Fe 3+ This arrangement allows the anode 11 and the cathode 12 to be staggered inside and outside the anode chamber 6 .

[0049] Preferably, the conductive carrier particle anode and the iron-modified carbon felt cathode are both closely attached to the tube 13 covering the proton exchange membrane 8, which greatly reduces the electrode distance and reduces the mass transfer resistance.

[0050] like Figure 3 As shown, preferably, in the present invention, the aeration head 14 of the aeration system 9 is arranged at the junction of the anode 11 and the cathode 12. The aeration head 14 is arranged in a manner of aerating toward the position of the cathode 12 to reduce the impact of oxygen on the anaerobic environment of the anode chamber.

[0051] After power is supplied, when degrading organic pollutants in groundwater, the electroactive microorganisms 23 loaded on the surface of the conductive carrier particles in the anode 11 degrade the organic carbon source in the anode liquid and generate protons and electrons. Protons are transferred to the cathode chamber 7 through the small holes in the tube 13 through the proton exchange membrane 8, and electrons are transferred to the cathode 12 through the external circuit.

[0052] The cathode 12 needs to use O2 as an electron acceptor and combine with the protons transferred from the anode to generate H2O 2。 The H2O2 produced at the cathode reacts with the Fe 3+ Fe 2+ Fenton reaction occurs, efficiently and continuously degrading organic pollutants in groundwater.

[0053] Therefore, when the cathode and anode are misaligned, the aeration head aerates toward the cathode, which ensures that the cathode uses oxygen as an electron acceptor while greatly reducing the impact of oxygen on the anaerobic environment in the anode chamber. The aeration process can also blow away volatile and semi-volatile organic pollutants in organically contaminated groundwater.

[0054] Preferably, the anode chamber 6 is connected to a liquid storage tank 15 storing organic wastewater. The pipeline between the anode chamber 6 and the liquid storage tank 15 is provided with at least one second pump 17 for transporting the anode liquid from the liquid storage tank 15 to the deoxygenation system 18. The first pump 16 transports the deoxygenated organic wastewater to the anode chamber 6. The first pump 16 and the second pump 17 in the present invention can both be pumps capable of extracting fluids, such as water pumps.

[0055] The anolyte is organic wastewater that has been deoxygenated by the deoxygenation system 18, so that the electroactive microorganisms 23 carried on the surface of the conductive carrier particles filled in the anode section in the anode chamber 6 grow in an anaerobic environment.

[0056] After the operation of the bio-Fenton system of the present invention, based on the unique structure of the electrode, the anolyte and the catholyte can be degraded simultaneously, that is, the organic wastewater and the contaminated groundwater are degraded simultaneously to achieve synchronous purification. The present invention combines the circulation well technology with the bio-electro-Fenton technology to achieve in-situ, continuous and efficient remediation of organic contaminated groundwater.

[0057] Preferably, a plurality of the electrodes are arranged in parallel, and the horizontal position of the center of the cathode 12 is higher than the horizontal position of the center of the anode 11. For example, when the electrode is inclined relative to the axis of the circulation well, the height of the cathode 12 is higher than the height of the anode 11. Since the oxygen in the aeration head moves upward in the cathode liquid, the cathode 12 can fully receive oxygen at a higher position and reduce the impact of oxygen on the anode.

[0058] Preferably, if Figure 3 As shown in , several electrodes are arranged vertically in parallel, and in the vertical direction, the cathode 12 is located at the top of the anode 11. The electrodes are arranged vertically, so that the contact area between the oxygen in the aeration head and the cathode 12 is increased, thereby improving the degradation efficiency of the cathode.

[0059] Preferably, the electrode structure of the present invention is not limited to the exemplary structure proposed in the present invention. The chamber in the electrode of the present invention may also include other structures, for example, the cathode and the anode may not be directly adjacent, and other structures that do not affect the operation of the cathode and the anode can be arranged between the cathode and the anode. For example, the chamber in the electrode may not extend to the cathode end or the anode end, and may be shorter than the length of the current example.

[0060] For example, when the gas from the aeration head can be guided by certain structures to move toward the cathode and the conductive carrier particles of the anode can be limited in filling position by the mesh structure, the electrodes can be arranged horizontally or tilted to perform enhanced purification of organic wastewater and groundwater.

[0061] Preferably, in the anode section of the chamber, the structure in the chamber is not limited to a columnar chamber, but can be isolated into a plurality of sub-chambers that allow the anode liquid to flow through. The chamber can be isolated into a plurality of sub-chambers along the radial direction of the tube, or can be isolated into a plurality of sub-chambers along the axial direction of the tube, or can be isolated into a plurality of sub-chambers in other regular or irregular patterns. The conductive carrier particles are filled in a plurality of sub-chambers. The conductive carrier particles can fill all the sub-chambers, or can select some of the sub-chambers for filling.

[0062] There may or may not be any gaps between the sub-chambers. Preferably, when there are gaps between the sub-chambers, it is more conducive to increasing the contact area between the anolyte and the electroactive microorganisms 23 on the surface of the conductive carrier particles, and it is also conducive to reducing the extraction resistance of the anolyte, making the anolyte easier to be extracted.

[0063] Preferably, the chamber can also exist only inside the anode of the electrode. Anolyte is injected from one end of the anode and drawn out from the other end of the anode.

[0064] Preferably, the holes on the tube wall of the tube 13 may also be distributed only in the anode section.

[0065] Preferably, the present invention further comprises a vacuum pump 19 and a gas treatment device 20. The vacuum pump 19 is connected to the gas treatment device 20 through a pipeline. The pipeline connected to the vacuum pump 19 extends to the first screen section 21. Preferably, the pipeline connected to the vacuum pump 19 extends to the wellhead in the first screen section 21, and is used to extract the volatile and semi-volatile organic pollutants in the groundwater stripped by aeration and the carbon dioxide after the oxidation and decomposition of organic matter and send them to the gas treatment device 20. The gas treatment device 20 discharges the gas that meets the treatment standards into the atmosphere.

[0066] It should be noted that the above-mentioned specific embodiments are exemplary, and those skilled in the art can come up with various solutions inspired by the disclosure of the present invention, and these solutions also belong to the disclosure scope of the present invention and fall within the protection scope of the present invention. Those skilled in the art should understand that the present invention specification and its drawings are illustrative and do not constitute a limitation on the claims. The scope of protection of the present invention is defined by the claims and their equivalents. The present invention specification contains multiple inventive concepts, such as "preferably", "according to a preferred embodiment" or "optionally", all of which indicate that the corresponding paragraph discloses an independent concept, and the applicant reserves the right to file a divisional application based on each inventive concept.

Claims

1. A bioelectric Fenton component, characterized in that: At least comprising an anode chamber (6), The anode chamber (6) comprises an anode (11) and a cathode (12) which are staggered from the inside and the outside; The cathode (12) of the electrode is arranged outside a chamber coated with a proton exchange membrane (8), the anode (11) is arranged inside the chamber coated with a proton exchange membrane (8), and the cathode (12) and the anode (11) are arranged offset in the axial direction of the electrode; An aeration head (14) is provided at the junction of the anode (11) and the cathode (12); The electroactive microorganisms (23) loaded on the surface of the conductive carrier particles in the anode (11) degrade the organic carbon source in the anode liquid to produce protons and electrons. The cathode (12) uses oxygen as an electron acceptor and combines with protons transferred from the anode to generate H2O2, and Fe 3+ Generates Fe as electron acceptor 2+ A Fenton-like reaction occurs on the surface of the cathode (12) and degrades organic pollutants in the cathode liquid, so that the anode liquid injected into the chamber of the electrode and the cathode liquid in the circulation well are purified at the same time.

2. The bioelectric Fenton component according to claim 1, characterized in that: The component comprises a plurality of electrodes which are arranged in a staggered manner, wherein a plurality of cathodes (12) and a plurality of anodes (11) of the electrodes are spatially staggered in a manner of different distribution areas.

3. The bioelectric Fenton component according to claim 1 or 2, characterized in that: The electrode is provided with at least one chamber covered by a proton exchange membrane (8) to form an anode chamber (6) for injecting an anode liquid. The first part of the anode chamber (6) belonging to the anode section is filled with conductive carrier particles carrying electroactive microorganisms to form an anode (11), The outer surface of the second part of the anode chamber (6) belonging to the cathode section is coated with iron-modified carbon felt to form a cathode (12).

4. The bioelectric Fenton component according to claim 1 or 2, characterized in that: A plurality of the electrodes are arranged in parallel, and an electrode group consisting of the plurality of parallel electrodes can be arranged in the cathode liquid in any posture.

5. The bioelectric Fenton component according to claim 1 or 2, characterized in that: A plurality of the electrodes are arranged vertically in parallel, and the cathode (12) is located at the top of the anode (11).

6. The bioelectric Fenton component according to claim 1 or 2, characterized in that: The anode chamber (6) in the electrode is composed of a tube (13) whose outer surface is coated with a proton exchange membrane (8), wherein the tube wall of the tube (13) is provided with a plurality of holes penetrating the tube wall.

7. A circulation well device based on the bioelectric Fenton assembly according to any one of claims 1 to 6, characterized in that: The well body (1) of the circulation well is divided by a packer (4) into at least two parts, namely a first screen section (21) and a second screen section (22); the position of the first screen section (21) is higher than the position of the second screen section (22); and the circulation well device comprises a bioelectric Fenton component arranged in the first screen section (21) of the circulation well.

8. A circulation well system based on the circulation well device according to claim 7, characterized in that: The circulation well system at least comprises a circulation well device, a water pumping and injection component and an in-well bioelectric Fenton component. The water pumping and injection component is used to realize water pumping and injection between different screen sections of the circulation well. The circulation well system also comprises an aeration system, and the aeration head (14) is arranged in a manner of aerating toward the position where the cathode (12) is located, so as to reduce the impact of oxygen on the anaerobic environment of the anode chamber.

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