Three-dimensional electrode electrocoagulation device

Abstract

The utility model discloses a three -dimensional electrode electric flocculation device relates to sewage treatment technical field, include: reactor shell, three -dimensional electrode module, electrode module, microwell plate or diaphragm, aeration device, external power supply, and electrode module includes cathode plate and anode plate, is connected with external power supply negative pole and positive pole respectively, and three -dimensional electrode module is made of the granular electrode of countless chimney soot modified sludge base biochar, and electrode module clamps three -dimensional electrode module in the middle. The three -dimensional electrode electric flocculation device disclosed by the utility model has the advantages that fluid can flow through the inside and surface of three -dimensional electrode, electrochemical oxidation-reduction reaction can be carried out on the surface of each granular electrode in three -dimensional electrode, electrode spacing is reduced, mass transfer efficiency is greatly improved, and appropriate aeration amount is beneficial to improving hydraulic condition, reducing the generation of short-circuit current, improving electrolytic efficiency, and effectively improving the effect of pollutant removal efficiency.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, and in particular to a three-dimensional electrode electrocoagulation device. Background Technology

[0002] In the chemical industry, electrocoagulation (EC) is a highly efficient and environmentally friendly water treatment technology commonly used in the treatment of industrial wastewater, domestic sewage, and drinking water purification. An electrocoagulation reactor typically consists of four parts: a power supply, a reaction tank, reaction electrodes, and a stirring / circulation system. Compared to traditional flocculation technologies, electrocoagulation technology offers significant advantages, such as simple operation, short operating time, no secondary pollution, high treatment efficiency, and low sludge production.

[0003] Three-dimensional electrodes, as a novel electrochemical reaction system, are composed of granular electrodes packed between the main electrode plates of a traditional two-dimensional electrolyzer. These granular electrodes become polarized and charged through electrostatic induction under the applied electric field of the main electrode. Each granular electrode becomes an independent working electrode, i.e., a third electrode. Electrochemical redox reactions can occur simultaneously on the surface of both the main electrode and each granular electrode, which reduces the electrode spacing and improves mass transfer efficiency.

[0004] Steelmaking flue ash (SFA), a major byproduct of the steel industry, possesses dual attributes of waste and resource. It contains a large amount of metal oxides, primarily ferric oxide (Fe₂O₃). Most flue ash is stockpiled as solid waste; however, due to its small particle size and tendency to form dust, it also generates wastewater after being corroded by acid rain, thus causing some environmental pollution.

[0005] Municipal sewage sludge is a byproduct of urban wastewater treatment. It mainly consists of organic matter, pathogens, heavy metals, inorganic particles, and colloids, and is characterized by high moisture content, easy putrefaction, and potential for pollution. As a byproduct of wastewater treatment, it is produced in large quantities, has low disposal efficiency, and contains certain harmful substances, making it a solid waste urgently needing disposal. In recent years, pyrolysis has become a focus of attention in the field of sludge treatment. However, sludge pyrolysis inevitably produces nitrogenous pollutants, causing pollution to the environment such as acid rain and ozone layer depletion. Biochar, used as an adsorbent in synergistic effects with electrocoagulation technology, is widely applied in wastewater treatment. It is commonly prepared by pyrolysis of biomass such as sludge, straw, and wood under oxygen-limited conditions. The preparation of biochar from sludge is a novel sludge treatment method that has received extensive research in recent years. Through high-temperature carbonization, heavy metals can be stably present in the sludge-derived biochar, thus significantly reducing the potential risk of heavy metal pollution during wastewater sludge application. However, biochar prepared from municipal sludge has insufficient adsorption active sites, low conductivity, and weak stability and regeneration capacity.

[0006] Therefore, it is urgent to develop a particulate electrode with high specific surface area, abundant active sites, high conductivity and catalytic activity, and to develop a technology with high mass transfer and current utilization efficiency, so as to improve the efficiency of pollutant removal. At the same time, realizing the resource utilization of solid waste and reducing the total cost of the equipment should also be considered. Utility Model Content

[0007] This utility model discloses a three-dimensional electrode electrocoagulation device, which aims to solve the technical problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: A three-dimensional electrode electrocoagulation device includes a reactor shell, on which a three-dimensional electrode module, an electrode module, a microporous plate, an aeration device, and an external power supply are respectively disposed. The inner cavity of the reactor shell is used to accommodate the core electrode module and related accessories as well as the aeration device. The three-dimensional electrode module and the electrode module both serve as electrodes for electrochemical oxidation-reduction reactions.

[0009] The electrode module includes an anode plate and a cathode plate, and the electrode module clamps the three-dimensional electrode module in the middle. The anode plate and cathode plate in the electrode module are respectively connected to the positive and negative terminals of an external power source.

[0010] The reactor shell has an opening with a perforated acrylic plate for fixing the two electrode plates of the electrode module, and an opening at the lower end for inserting the aeration duct of the aeration device.

[0011] The three-dimensional electrode module serves as both an electrode and a channel for fluid flow.

[0012] The aeration device includes an aeration head, an aeration conduit, and a manipulator. The aeration conduit extends into the inner cavity of the reactor through the lower opening of the reactor shell. In the aeration chamber, the gas is dispersed by the aeration head. The generated bubbles are sheared twice by the microporous plate to form micron-sized bubbles with uniform particle size. While maintaining the stability of the three-dimensional electrode bed, it significantly increases the dissolved oxygen concentration in the liquid phase and enhances mass transfer through the turbulence effect at the gas-liquid interface.

[0013] The microporous plate is used to separate the three-dimensional electrode module and the aeration device inside the reactor shell. Positioning plates are fixedly installed on both sides of the top of the perforated acrylic plate. Insert rods are inserted into the positioning plates. One end of the insert rod passes through the electrode module and extends to the outside of the electrode module. A baffle is fixedly installed at one end of the insert rod. A threaded ring is connected to the surface of the insert rod. A tension spring is arranged around the surface of the insert rod. One end of the tension spring is fixedly connected to one side of the positioning plate, and the other end of the tension spring is fixedly connected to one side of the baffle. The above components restrict the spatial distribution of the particulate electrodes to the bottom of the reactor, while maintaining the gas-liquid mass transfer channel between the aeration device and the electrochemical oxidation-reduction active area.

[0014] The electrode modules should possess good conductivity, corrosion resistance, and chemical stability. The materials of the electrode modules include: titanium suboxide, ruthenium-iridium titanium alloy, titanium-based alloy, and graphite. The microporous plate should have appropriate porosity and good air permeability. The materials of the microporous plate include: titanium, nickel-based alloy, alumina, silicon carbide (SiC), PTFE membrane, PVDF membrane, nylon filter cloth, metal-polymer composite mesh, ceramic fiber reinforced resin plate, etc. The structural forms of the microporous plate include: single-layer microporous plate, multi-layer gradient filtration, dynamic anti-clogging structure, and multi-layer composite structure.

[0015] In a preferred embodiment, the biochar of the granular electrode is produced by pyrolysis carbonization of municipal sludge modified with flue ash.

[0016] In a preferred embodiment, PTFE is used as a binder for the granular electrode to clump together the powdered biochar and granulate it by hand. The diameter of the granular electrode is between 3.5 and 3.7 mm.

[0017] In a preferred embodiment, the inner cavity of the reactor shell is divided into two parts by the microporous plate: the upper part is where the electrochemical oxidation-reduction reaction takes place, and the lower part is the aeration chamber.

[0018] In a preferred embodiment, a perforated acrylic plate is provided at the opening of the reactor shell to fix the electrode plates in the electrode module.

[0019] In a preferred embodiment, the aeration device is located at the bottom of the reactor shell and disperses the gas evenly through a microporous plate, which can both provide dissolved oxygen and agitate the fluid.

[0020] The device features a simple structure, convenient operation, and low cost. Due to its greater number of active sites and higher mass transfer efficiency, it achieves the same treatment effect at a lower voltage compared to two-dimensional electrode electrocoagulation, thus reducing energy consumption. The metal components in flue ash significantly enhance the surface active sites of biochar, thereby significantly improving its adsorption performance. The granular electrode in the three-dimensional granular electrode is made of a mixture of modified biochar and PTFE, exhibiting good mechanical strength, excellent chemical and electrochemical stability. Furthermore, the porous structure inside the granular electrode promotes turbulence and dispersion, helping to alleviate the concentration polarization problem of two-dimensional electrodes. Simultaneously, the abundant porous structure inside the granular electrode gives it a large adsorption capacity, allowing for multiple batches of recycling and demonstrating good regeneration performance.

[0021] In a preferred embodiment, a wrench is fixedly installed at one end of the screw ring, and the surface of the wrench has anti-slip texture. A handle is fixedly installed on one side of the baffle, and the surface of the handle has anti-slip texture. Both the electrode module and the positioning plate have insertion holes for the insertion rod to pass through, and the inner wall of the insertion hole is slidably connected to the surface of the insertion rod.

[0022] With the positioning plate and insert rod, the insert rod can be pulled to separate from the electrode module during use, which facilitates the removal of the limit operation and the installation and positioning operation, thereby improving the ease of use of the device.

[0023] As can be seen from the above, the three-dimensional electrode electrocoagulation device provided by this utility model has the following technical effects.

[0024] Firstly, the device offers advantages such as simple structure, convenient operation, and low cost. Due to its greater number of active sites and higher mass transfer efficiency, it achieves the same treatment effect at a lower voltage compared to two-dimensional electrode electrocoagulation, thus reducing energy consumption. The metal components abundant in flue ash significantly enhance the surface active sites of biochar, thereby significantly improving its adsorption performance. The electrodes in the three-dimensional granular electrode are made of a mixture of modified biochar and PTFE, possessing good mechanical strength, excellent chemical and electrochemical stability. Furthermore, the porous structure inside the granular electrode promotes turbulence and dispersion, helping to alleviate the concentration polarization problem of the two-dimensional electrode. Simultaneously, the abundant porous structure inside the granular electrode gives it a large adsorption capacity, allowing for multiple batches of recycling and exhibiting good regeneration performance.

[0025] Secondly, the positioning plate and the insertion rod allow the insertion rod to be pulled to separate from the electrode module during use, making it easier to remove the limit operation and to install and position the device, thus improving its ease of use.

[0026] Secondly, by dispersing the gas through the aeration head in the aeration chamber, the generated bubbles are sheared twice by the microporous plate to form micron-sized bubbles with uniform particle size. While maintaining the stability of the three-dimensional electrode bed, the dissolved oxygen concentration in the liquid phase is significantly increased, and mass transfer is enhanced through the turbulence effect at the gas-liquid interface. Attached Figure Description

[0027] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0028] Figure 2 This is a three-dimensional sectional view of the present invention.

[0029] Figure 3 This utility model Figure 1 Enlarged schematic diagram of the structure at point A in the middle.

[0030] Figure 4 This utility model Figure 2 Enlarged schematic diagram of the structure at point B.

[0031] In the attached diagram: 1. Reactor shell; 2. Three-dimensional electrode module; 3. Electrode module; 4. Microporous plate; 6. External power supply; 7. Perforated acrylic plate; 5. Aeration device; 8. Aeration head; 9. Aeration duct; 10. Manipulator; 11. Positioning plate; 12. Insert rod; 13. Baffle; 14. Threaded ring; 15. Tension spring. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0033] Reference Figures 1-4 A three-dimensional electrode electrocoagulation device includes a reactor shell 1. A three-dimensional electrode module 2, an electrode module 3, a microporous plate 4, an aeration device 5, and an external power supply 6 are respectively arranged in the reactor shell 1. The inner cavity of the reactor shell 1 is used to accommodate the core electrode module and related accessories, as well as the aeration device 5. The three-dimensional electrode module 2 and the electrode module 3 both serve as electrodes for electrochemical oxidation-reduction reactions. The inner cavity of the reactor shell 1 is divided into two parts by the microporous plate 4. The upper part is the place where the electrochemical oxidation-reduction reaction takes place, and the lower part is the aeration chamber. An open acrylic plate 7 is provided at the opening of the reactor shell 1 to fix the electrode plate in the electrode module 3.

[0034] Electrode module 3 includes an anode plate and a cathode plate. Electrode module 3 clamps three-dimensional electrode module 2 in the middle. Three-dimensional electrode module 2 and electrode module 3 are electrically connected to the positive and negative terminals of external power supply 6, respectively.

[0035] A perforated acrylic plate 7 is provided at the opening of the reactor shell 1 to fix the two electrode plates of the electrode module 3, and an opening is provided at the lower end for the aeration conduit 9 of the aeration device 5 to be inserted. The aeration device 5 is located at the bottom of the reactor shell 1 and disperses the gas evenly through the microporous plate 4, which can provide dissolved oxygen and stir the fluid. This device has the advantages of simple structure, convenient operation and low cost. Due to its more active sites and higher mass transfer efficiency, it can achieve the same treatment effect at a lower voltage compared with two-dimensional electrode electrocoagulation, and the energy consumption is reduced. The metal components rich in flue ash significantly enhance the surface active sites of biochar, thereby significantly improving its adsorption performance. The granular electrode in the three-dimensional granular electrode is made of modified biochar and PTFE, which has good mechanical strength, excellent chemical and electrochemical stability, and the porous structure inside the granular electrode promotes turbulence and dispersion, which helps to alleviate the concentration polarization problem of two-dimensional electrode. At the same time, the rich porous structure inside the granular electrode gives it a large adsorption capacity, which can be recycled in multiple batches and has good regeneration performance.

[0036] The three-dimensional electrode module 2 serves as both an electrode and a channel for fluid flow.

[0037] The aeration device 5 includes an aeration head 8, an aeration conduit 9, and a manipulator 10. The aeration conduit 9 extends into the inner cavity of the reactor through the lower opening of the reactor shell 1. In the aeration chamber, the gas is dispersed through the aeration head 8. The generated bubbles are sheared twice by the microporous plate 4 to form micron-sized bubbles with uniform particle size. While maintaining the stability of the three-dimensional electrode bed, it significantly increases the dissolved oxygen concentration in the liquid phase and enhances mass transfer through the turbulence effect at the gas-liquid interface.

[0038] The microporous plate 4 separates the three-dimensional electrode modules 2 and 3 inside the reactor shell 1 from the aeration device 5. Positioning plates 11 are fixedly installed on both sides of the top of the perforated acrylic plate 7. Insertion rods 12 are inserted into the positioning plates 11, with one end of the rod passing through the electrode module 3 and extending to its exterior. A baffle 13 is fixedly installed at one end of the rod 12. A threaded ring 14 is threaded onto the surface of the rod 12, and a tension spring 15 is arranged around its surface. One end of the tension spring 15 is fixedly connected to one side of the positioning plate 11, and the other end is fixedly connected to one side of the baffle 13. These components restrict the spatial distribution of the granular electrodes towards the bottom of the reactor while maintaining the gas-liquid mass transfer channel between the aeration device 5 and the electrochemical oxidation-reduction active area. The biochar of the granular electrodes is obtained by using smoke... The biochar is produced by modifying municipal sludge and then pyrolyzing and carbonizing it. PTFE is used as a binder for the granular electrodes to form agglomerated powdered biochar. The granules are manually granulated, with a diameter between 3.5-3.7 mm. A wrench is fixedly installed at one end of the screw ring 14, and the surface of the wrench has anti-slip texture. A handle is fixedly installed on one side of the baffle 13, and the surface of the handle also has anti-slip texture. Both the electrode module 3 and the positioning plate 11 have insertion holes for the insertion rod 12 to pass through. The inner wall of the insertion hole is slidably connected to the surface of the insertion rod 12. During use, the positioning plate 11 and the insertion rod 12 can be separated from the electrode module 3 by pulling the insertion rod 12, which facilitates the removal of the limit operation and also facilitates the installation and positioning operation, thereby improving the ease of use of the device.

[0039] The electrode module 3 should have good conductivity, corrosion resistance, and chemical stability. The materials of the electrode module 3 include: titanium suboxide, ruthenium-iridium titanium alloy, titanium-based alloy, and graphite. The microporous plate 4 should have appropriate porosity and good air permeability. The materials of the microporous plate 4 include: titanium, nickel-based alloy, alumina, silicon carbide (SiC), PTFE membrane, PVDF membrane, nylon filter cloth, metal-polymer composite mesh, ceramic fiber reinforced resin plate, etc. The structural forms of the microporous plate 4 include: single-layer microporous plate, multi-layer gradient filtration, dynamic anti-clogging structure, and multi-layer composite structure.

[0040] Working principle: Sludge from the sludge pond of a sewage treatment plant is mixed with steelmaking flue ash in a certain proportion and then pyrolyzed at high temperature in a muffle furnace under a nitrogen atmosphere. After the pyrolysis process is completed, the power is turned off and the muffle furnace is allowed to cool naturally. The biochar sample is then removed, and the modified biochar is mixed with PTFE emulsion and manually granulated. The diameter is measured with vernier calipers and controlled within 3.5-3.7 mm. The granular sample is then placed in the muffle furnace and dried at 100°C for 2 hours to remove excess moisture from the granular electrode. After drying, the sample is removed and cooled to room temperature to produce the granular electrode used in this embodiment. A water sample prepared with potassium dihydrogen phosphate is used as phosphorus-containing wastewater. When the voltage of the three-dimensional electrode electrocoagulation reaction device is constant, the device can be tested to ensure successful startup.

[0041] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. The substitutions may be replacements of some structures, devices, or method steps, or they may be complete technical solutions. Equivalent substitutions or modifications made based on the technical solution and inventive concept of this utility model should all be covered within the protection scope of this utility model.

Claims

1. A three-dimensional electrode electrocoagulation device, comprising a reactor shell (1), characterized in that: The reactor shell (1) is provided with a three-dimensional electrode module (2), an electrode module (3), a microporous plate (4), an aeration device (5), and an external power supply (6). The inner cavity of the reactor shell (1) is used to accommodate the core electrode module and related accessories as well as the aeration device (5). The three-dimensional electrode module (2) and the electrode module (3) are both used as electrodes for electrochemical oxidation-reduction reactions. The electrode module (3) includes an anode plate and a cathode plate. The electrode module (3) clamps the three-dimensional electrode module (2) in the middle. The three-dimensional electrode module (2) and the electrode module (3) are electrically connected to the positive and negative terminals of the external power supply (6), respectively. The reactor shell (1) has an opening with a perforated acrylic plate (7) for fixing the two electrode plates of the electrode module (3), and an opening at the lower end for inserting the aeration duct (9) of the aeration device (5). The three-dimensional electrode module (2) serves as both an electrode and a channel for fluid flow. The aeration device (5) includes an aeration head (8), an aeration conduit (9), and an operating machine (10). The aeration conduit extends into the inner cavity of the reactor through the lower opening of the reactor shell (1).

2. The three-dimensional electrode electrocoagulation device according to claim 1, characterized in that, The microporous plate (4) is used to separate the three-dimensional electrode module (2), electrode module (3) and aeration device (5) inside the reactor shell (1). Positioning plates (11) are fixedly installed on both sides of the top of the perforated acrylic plate (7). Insertion rods (12) are inserted on the positioning plates (11). One end of the insertion rod (12) passes through the electrode module (3) and extends to the outside of the electrode module (3). A baffle (13) is fixedly installed on one end of the insertion rod (12). A threaded ring (14) is threaded on the surface of the insertion rod (12). A tension spring (15) is arranged around the surface of the insertion rod (12). One end of the tension spring (15) is fixedly connected to one side of the positioning plate (11), and the other end of the tension spring (15) is fixedly connected to one side of the baffle (13).

3. The three-dimensional electrode electrocoagulation device according to claim 1, characterized in that, The inner cavity of the reactor shell (1) is divided into two parts by the microporous plate (4). The upper part is the site for electrochemical oxidation-reduction reaction, and the lower part is the aeration chamber.

4. The three-dimensional electrode electrocoagulation device according to claim 1, characterized in that, The reactor shell (1) has an opening with a perforated acrylic plate (7) for fixing the electrode plate in the electrode module (3).

5. The three-dimensional electrode electrocoagulation device according to claim 1, characterized in that, The aeration device (5) is located at the bottom of the reactor shell (1) and disperses the gas evenly through the microporous plate (4).

6. The three-dimensional electrode electrocoagulation device according to claim 2, characterized in that, A wrench is fixedly installed at one end of the screw ring (14), and the surface of the wrench is provided with anti-slip texture. A handle is fixedly installed on one side of the baffle (13), and the surface of the handle is provided with anti-slip texture. The electrode module (3) and the positioning plate (11) are both provided with insertion holes for the insertion rod (12) to pass through. The inner wall of the insertion hole is slidably connected to the surface of the insertion rod (12).

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