Sludge treatment system with integrated microbial fuel cell and treatment method thereof

Abstract

The present invention relates to the technical field of sewage treatment and resource utilization, and in particular to a sludge treatment system with an integrated microbial fuel cell and a treatment method thereof. The system comprises a sludge compression chamber and a pretreatment unit, wherein a first anode plate is provided at one end of the sludge compression chamber, and a first cathode plate matching the first anode plate is slidably provided at the other end of the sludge compression chamber. A driving mechanism for driving the first cathode electrode plate toward or away from the first anode electrode plate is provided on the sludge compression chamber, and a sludge discharge port is provided below the sludge compression chamber. When in use, chloride salt and tannic acid are added to the sludge in the pretreatment barrel, wherein the chloride salt is used to improve the electrochemical wall breaking effect of the sludge, and the tannic acid is used to improve the dehydration performance of the sludge and reduce the hydrothermal dehydration temperature of the sludge. The sludge is mixed in the pretreatment barrel and then enters a fuel tank for chemical reaction to generate electrical energy to provide power for a battery. Microorganisms can degrade organic matter in the sludge.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment and resource utilization, and in particular to a sludge treatment system with an integrated microbial fuel cell and a treatment method thereof. Background Art

[0002] Sludge, an inevitable byproduct of sewage treatment, faces significant challenges in efficient and environmentally friendly treatment technologies. In traditional sludge treatment processes, dehydration and drying units consume significant amounts of energy, accounting for 44% to 82% of the system's total energy consumption and becoming a key constraint on energy conservation and emission reduction in sewage treatment plants.

[0003] Common sludge dewatering devices on the market, such as belt filter presses, screw-type sludge dewatering machines, and plate and frame filter presses, can dewater sludge through pressure extrusion, but they generally suffer from low dewatering efficiency, high water content in the treated sludge, and inconvenience in subsequent transportation and disposal. These issues not only increase the operating costs of sewage treatment plants but can also cause secondary pollution, hindering environmental sustainability.

[0004] Therefore, innovating sludge treatment technologies, improving dewatering efficiency, reducing energy consumption, and achieving sludge reduction, harmlessness, and resource utilization have become critical challenges for current sewage treatment plants. Against this backdrop, the present invention proposes a sludge treatment system and method with an integrated microbial fuel cell, aiming to achieve efficient, energy-saving, and environmentally friendly sludge treatment through advanced technological means. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: in order to solve the problems of low dehydration efficiency and high energy consumption in traditional sludge treatment processes, a sludge treatment system with an integrated microbial fuel cell and a treatment method thereof are provided.

[0006] The technical solution adopted by the present invention to solve its technical problems is: a sludge treatment system with an integrated microbial fuel cell, including a sludge compression chamber and a pretreatment unit, a first anode plate is provided at one end of the sludge compression chamber, a first cathode plate matching the first anode plate is slidably provided at the other end of the sludge compression chamber, a driving mechanism for driving the first cathode electrode plate toward or away from the first anode electrode plate is provided on the sludge compression chamber, and a sludge discharge port is provided below the sludge compression chamber;

[0007] The pretreatment unit includes a pretreatment barrel, a fuel tank and a battery. A stirring mechanism and a heating mechanism are provided in the pretreatment barrel. A second anode plate, a second cathode plate and an ion exchange membrane are provided in the fuel tank. The ion exchange membrane divides the fuel tank into a first chamber and a second chamber. The second anode plate is located in the first chamber, and the second cathode plate is located in the second chamber. The battery is connected to the first anode plate, the second anode plate, the first cathode plate and the second cathode plate respectively. The pretreatment barrel is connected to the first chamber. The second anode plate and the second cathode plate are used to transmit the electrical energy generated in the reaction to the battery for energy storage. The battery is used to transmit electrical energy to the first anode plate and the first cathode plate. The first chamber and the second chamber are both connected to the outside, and the bottom of the first chamber is connected to the sludge compression chamber. Compared with the existing technology, this solution first pre-treats the sludge by the pre-treatment unit to improve the dehydration performance of the sludge and reduce the hydrothermal dehydration temperature, thereby increasing the extrusion force on the sludge and improving the subsequent sludge extrusion dehydration efficiency. At the same time, the pre-treatment unit generates electricity through chemical reaction with the sludge and stores the energy in the battery, which then supplies power to the first anode plate and the first cathode plate to achieve self-sufficiency.

[0008] In some preferred embodiments, the sludge compression chamber is provided with a connection port for connecting the first chamber with the interior of the sludge compression chamber, and a filter plate is mounted on the connection port. The filter plate primarily serves as a filter in the sludge treatment system. Installed on the connection port, it prevents sludge from directly entering the sludge compression chamber while allowing liquid or smaller particles in the pretreated sludge to pass through, while larger solid particles or impurities are trapped by the filter plate. This ensures that the sludge entering the sludge compression chamber has been purified to a certain extent, facilitating subsequent electrolysis and dehydration processes.

[0009] In some preferred embodiments, the pretreatment barrel is topped with a sealing cover, and the stirring mechanism is mounted on the sealing cover, forming a sealed chamber between the sealing cover and the pretreatment barrel. Since the sludge and added chemicals, such as chloride salts and tannic acid, need to mix and react at a certain temperature during the pretreatment process, the sealing cover effectively prevents these substances from volatilizing or leaking into the environment during the heating and stirring process, thereby avoiding potential harm to operators and pollution to the surrounding environment.

[0010] To facilitate the treatment of dehydrated sludge, some embodiments preferably further include a water outlet pipe and a mud delivery pipe. The water outlet pipe is connected to the mud discharge port, one end of the mud delivery pipe is connected to the water outlet pipe, and the other end of the mud delivery pipe is connected to a mud storage hopper. The water outlet pipe is provided with a plurality of drainage holes for draining water generated during squeezing.

[0011] In order to facilitate the control of the sludge in the pretreatment barrel, in some preferred embodiments, the pretreatment barrel and the first chamber are connected via an external pipe, and a valve is provided on the external pipe.

[0012] In order to ensure stable and reliable operation of the first anode plate and the second cathode plate, in some preferred embodiments, the first anode plate and the first cathode plate are both made of lead dioxide, so that the first anode plate and the second cathode plate have good electrical conductivity and corrosion resistance.

[0013] In some preferred embodiments, the second anode plate is made of carbon cloth or graphite felt, and the second cathode plate is a titanium mesh having a platinum-carbon catalyst coating. The second anode plate has high electrical conductivity, good biocompatibility, and corrosion resistance, and the second cathode plate has high catalytic activity and stability.

[0014] In some preferred embodiments, the ion exchange membrane is a Nafion membrane, which has high selectivity and permeability to ensure high performance and stability of the biofuel cell.

[0015] In some preferred embodiments, the fuel tank is provided with an input pipe and an output pipe, the input pipe is communicated with the second cavity and with an external gas source for delivering oxygen, and the output pipe is communicated with the first cavity.

[0016] A treatment method using the above-mentioned sludge treatment system with an integrated microbial fuel cell, the specific operating steps are as follows:

[0017] S1. Chloride salt, tannic acid and sludge are added to a pretreatment barrel, mixed by a stirring mechanism and heated by a heating mechanism to break down the cell walls of microorganisms in the sludge and release the water and organic matter in the cells;

[0018] S2. After mixing is completed, it is transported to the first chamber of the fuel chamber. The second anode plate in the first chamber contacts the sludge. Microorganisms oxidize the organic matter in the sludge through metabolic activities and produce electrons, protons and carbon dioxide, and transport oxygen to the second chamber. Oxygen serves as an electron acceptor. At the same time, protons pass through the ion exchange membrane and combine with electrons transferred from the second cathode plate through the external circuit to produce a reduction reaction to generate water. The chemical reactions between the sludge and the second anode plate, and between the protons and the second cathode plate release electrons. The electrons flow to generate electrical energy and store it in the battery.

[0019] S3. The treated sludge enters the sludge compression chamber, where the driving mechanism drives the first cathode plate to move toward the first anode plate. The first anode plate and the first cathode plate are powered by batteries, squeezing and electrolyzing the sludge in the sludge compression chamber to achieve sludge dehydration.

[0020] S4. The dehydrated sludge enters the drainage pipe through the mud discharge port at the bottom, and then enters the mud storage hopper through the mud delivery pipe.

[0021] The beneficial effects of the present invention are as follows: when in use, the sludge treatment system and treatment method of the present invention with an integrated microbial fuel cell are added with chloride salt and tannic acid to the sludge in the pretreatment barrel, the chloride salt is used to improve the electrochemical wall breaking effect of the sludge, and the tannic acid is used to improve the dehydration performance of the sludge and reduce the hydrothermal dehydration temperature. The sludge is mixed in the pretreatment barrel and then enters the fuel tank for chemical reaction and generates electricity to provide power for the battery. The microorganisms can degrade organic matter in the sludge, thereby improving the utilization rate of the organic matter in the sludge. The microbial fuel cell is combined with the electrolytic dehydration technology, and the electricity generated by the microbial fuel cell is used to directly power the electrolysis process, thereby achieving energy self-sufficiency, reducing dependence on external energy, and reducing energy consumption. The sludge is then sent to the sludge compression chamber for extrusion and electrolytic dehydration. The first anode plate and the first cathode plate have a heating function for the sludge. The water vaporization expansion on the electrode surface greatly increases the extrusion force on the sludge, thereby achieving deeper dehydration of the sludge, avoiding the problems of low dehydration efficiency and high energy consumption in traditional sludge treatment processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below with reference to the accompanying drawings and examples.

[0023] Figure 1 It is a structural schematic diagram of the present invention;

[0024] Figure 2 yes Figure 1 A partial enlarged view of middle A;

[0025] Figure 3 yes Figure 1 A partial enlarged view of B.

[0026] In the figure: 1. sludge compression chamber, 2. first anode plate, 3. first cathode plate, 4. driving mechanism, 5. mud discharge port, 6. pretreatment barrel, 7. fuel tank, 8. battery, 9. stirring mechanism, 10. heating mechanism, 11. second anode plate, 12. second cathode plate, 13. ion exchange membrane, 14. first cavity, 15. second cavity, 16. connecting port, 17. filter plate, 18. sealing cover, 19. water outlet pipe, 20. mud delivery pipe, 21. mud storage hopper, 22. drainage hole, 23. valve, 24. input pipe, 25. output pipe. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the embodiments:

[0028] The present invention is not limited to the following specific embodiments. Based on the disclosure of the present invention, a person skilled in the art may adopt a variety of other specific embodiments to implement the present invention. Any simple changes or modifications made to the design structure and concept of the present invention fall within the scope of protection of the present invention. It should be noted that the embodiments and features of the embodiments of the present invention may be combined with each other unless they conflict.

[0029] Example 1, as Figure 1-3 As shown, a sludge treatment system with an integrated microbial fuel cell includes a sludge compression chamber 1, a pretreatment unit, a water outlet pipe 19 and a mud delivery pipe 20. A first anode plate 2 is provided at one end of the sludge compression chamber 1, and a first cathode plate 3 matching the first anode plate 2 is slidably provided at the other end of the sludge compression chamber 1. The first anode plate 2 and the first cathode plate 3 are arranged opposite to each other. A driving mechanism 4 is provided on the sludge compression chamber 1. The driving mechanism 4 is used to drive the cathode electrode plate to approach or move away from the anode electrode plate to achieve electrolysis and extrusion dehydration of the sludge in the compression chamber. In this embodiment, the driving mechanism 4 is a cylinder. In addition to the cylinder, it can also be an electric push rod. A mud discharge port 5 is provided below the sludge compression chamber 1. The mud discharge port 5 is used to discharge the dehydrated sludge in the sludge compression chamber 1 and to discharge water during extrusion. The water outlet pipe 19 is connected to the mud discharge port 5, one end of the mud delivery pipe 20 is connected to the water outlet pipe 19, and the other end of the mud delivery pipe 20 is connected to a mud storage hopper 21. A plurality of drainage holes 22 are provided on the water outlet pipe 19.

[0030] The pretreatment unit includes a pretreatment barrel 6, a fuel tank 7 and a battery 8. A stirring mechanism 9 and a heating mechanism 10 are provided in the pretreatment barrel 6. In this embodiment, the stirring mechanism 9 includes a motor for driving a stirring paddle to rotate the stirring paddle. The heating mechanism 10 is a motor heat pipe. A second anode plate 11, a second cathode plate 12 and an ion exchange membrane 13 are provided in the fuel tank 7. The ion exchange membrane 13 divides the fuel tank 7 into a first cavity 14 and a second cavity 15. The second anode plate 11 is located in the first cavity 14, and the second cathode plate 12 is located in the second cavity 15. The battery 8 is connected to the first anode plate 2, the second anode plate 11, the first cathode plate 3 and the second cathode plate 12 respectively. The pretreatment barrel 6 and the first The cavity 14 is connected, the second anode plate 11 and the second cathode plate 12 are used to transmit the electrical energy generated in the reaction to the battery 8 for energy storage, and the battery 8 is used to transmit electrical energy to the first anode plate 2 and the first cathode plate 3. The first cavity 14 and the second cavity 15 are both connected to the outside. A connecting port 16 is provided on the sludge compression chamber 1. The connecting port 16 is used to connect the first cavity 14 with the sludge compression chamber 1. A filter plate 17 is installed on the connecting port 16 to achieve communication between the bottom of the first cavity 14 and the sludge compression chamber 1. An input pipe 24 and an output pipe 25 are provided on the fuel tank 7. The input pipe 24 is connected to the second cavity 15 and is connected to an external gas source for transmitting oxygen, and the output pipe 25 is connected to the first cavity 14.

[0031] The upper cover of the pretreatment barrel 6 is provided with a sealing cover 18 , and the stirring mechanism 9 is installed on the sealing cover 18 .

[0032] The pretreatment barrel 6 and the first chamber 14 are connected via an external pipe, and a valve 23 is provided on the external pipe.

[0033] The first anode plate 2 and the first cathode plate 3 are both made of lead dioxide.

[0034] The second anode plate 11 is made of carbon cloth or graphite felt, and the second cathode plate 12 is made of a titanium mesh having a platinum-carbon catalyst coating.

[0035] The ion exchange membrane 13 adopts Nafion membrane, which is a high-performance ion exchange membrane 13. The Nafion membrane is mainly composed of a polytetrafluoroethylene skeleton and proton exchange groups. The main function of the ion exchange membrane 13 is to separate the two chambers of the fuel tank 7, allowing specific ions or molecules to pass through while preventing other substances from passing through. Under normal circumstances, the ion exchange membrane 13 should be able to effectively prevent the passage of sludge or other macromolecular substances.

[0036] Example 2: Example 2 is a treatment method of Example 1, specifically: a treatment method using the above-mentioned sludge treatment system with an integrated microbial fuel cell, and the specific operating steps are as follows:

[0037] S1. Chloride salt, tannic acid, and sludge are added to a pretreatment barrel 6, mixed by a stirring mechanism 9, and heated by a heating mechanism 10, and subjected to a short-term hydrothermal treatment at a low temperature (160° C. in this embodiment). Chloride salt effectively breaks down the cell walls of microorganisms in the sludge, releasing water and organic matter within the cells, thereby improving the dehydration efficiency of subsequent electrolysis and mechanical extrusion, and reducing the energy consumption required for electrolysis.

[0038] S2. After mixing, the sludge is transported to the first chamber 14 of the fuel chamber. The second anode plate 11 in the first chamber 14 contacts the sludge. Microorganisms oxidize the organic matter in the sludge through metabolic activity and produce electrons, protons and carbon dioxide, and transport oxygen into the second chamber. Oxygen acts as an electron acceptor. At the same time, protons pass through the ion exchange membrane 13 and combine with electrons transferred from the second cathode plate 12 through the external circuit, causing a reduction reaction to produce water. Therefore, the chemical reactions between the sludge and the second anode plate 11, and between the protons, molecules, etc. and the second cathode plate 12 release electrons. The electrons flow, generate electrical energy, and are stored in the battery 8, thus forming a microbial fuel cell.

[0039] S3. The treated sludge passes through the filter plate 17 and enters the sludge compression chamber 1. The first cathode plate 3 is driven by the driving mechanism 4 to move toward the first anode plate 2. At the same time, the first anode plate 2 and the first cathode plate 3 are powered by the battery 8. The voltage range between the first anode plate 2 and the first cathode plate 3 is set between 20 and 35V. The sludge in the sludge compression chamber 1 is squeezed and electrolyzed. The first anode plate 2 and the first cathode plate 3 have a heating function for the sludge. The water vaporization and expansion on the contact surface of the first anode plate 2 and the first cathode plate 3 greatly increase the squeezing force of the sludge, thereby achieving deeper dehydration of the sludge. At the same time, when the sludge is squeezed between the first anode plate 2 and the first cathode plate 3, the water in the sludge is electrolyzed under the action of the electric field to produce hydrogen ions and hydroxide ions. Due to the electrolysis and the reaction of the complex components in the sludge , hydroxyl free radicals will be generated. Hydroxyl free radicals can penetrate the cell walls of microorganisms, destroy their structure, cause the cell walls to rupture, and release substances in the cells, thereby accelerating the decomposition and mineralization process of sludge. Once the cell walls are ruptured, hydroxyl free radicals will further oxidize organic substances such as proteins and nucleic acids in the cells, decomposing them into small molecules such as carbon dioxide, water and other inorganic substances, and help reduce the organic load in the sludge and improve the biodegradability of the sludge. The strong oxidizing property of hydroxyl free radicals can also kill harmful bacteria and viruses in the sludge, reduce the biological toxicity of the sludge, and make it safer and easier to handle. Furthermore, a limit switch is provided on the right side of the first anode plate 2. The limit switch is used to automatically stop the cylinder at the drive mechanism 4 when the first cathode plate 3 touches the limit switch on the first anode plate 2, so as to prevent excessive extrusion;

[0040] S4. The dehydrated sludge enters the drain pipe through the mud outlet 5 below, and then enters the mud storage hopper 21 through the mud conveying pipe 20. The microbial fuel cell is combined with the electrolytic dehydration technology. The electricity generated by the microbial fuel cell is used to directly power the electrolysis process, achieving energy self-sufficiency and reducing dependence on external energy. The microorganisms in the microbial fuel cell can degrade organic matter in the sludge, generating electricity and by-products such as carbon dioxide, thereby promoting the effective utilization of organic matter in the sludge.

[0041] The above description of the preferred embodiments of the present invention is intended to serve as a guide. Based on the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of this invention. The technical scope of this invention is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A sludge treatment system with an integrated microbial fuel cell, characterized in that: The invention comprises a sludge compression chamber (1) and a pretreatment unit, wherein a first anode plate (2) is provided at one end of the sludge compression chamber (1), a first cathode plate (3) matching the first anode plate (2) is slidably provided at the other end of the sludge compression chamber (1), a driving mechanism (4) for driving the first cathode electrode plate (2) to move closer to or away from the first anode electrode plate (3) is provided on the sludge compression chamber (1), and a sludge discharge port (5) is provided below the sludge compression chamber (1); The pretreatment unit comprises a pretreatment barrel (6), a fuel tank (7) and a storage battery (8). A stirring mechanism (9) and a heating mechanism (10) are provided in the pretreatment barrel (6). A second anode plate (11), a second cathode plate (12) and an ion exchange membrane (13) are provided in the fuel tank (7). The ion exchange membrane (13) divides the fuel tank (7) into a first chamber (14) and a second chamber (15). The second anode plate (11) is located in the first chamber (14), the second cathode plate (12) is located in the second chamber (15), and the storage battery (8) is provided with a plurality of electrodes. ) are respectively connected to the first anode plate (2), the second anode plate (11), the first cathode plate (3) and the second cathode plate (12); the pretreatment barrel (6) is connected to the first chamber (14); the second anode plate (11) and the second cathode plate (12) are used to transmit the electric energy generated in the reaction to the storage battery (8) for energy storage; the storage battery (8) is used to transmit electric energy to the first anode plate (2) and the first cathode plate (3); the first chamber (14) and the second chamber (15) are both connected to the outside; the bottom of the first chamber (14) is connected to the inside of the sludge compression chamber (1).

2. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: The sludge compression chamber (1) is provided with a connecting port (16), the connecting port (16) being used to connect the first cavity (14) and the sludge compression chamber (1), and a filter plate (17) is installed on the connecting port (16).

3. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: The upper cover of the pretreatment barrel (6) is provided with a sealing cover (18), and the stirring mechanism (9) is mounted on the sealing cover (18).

4. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: It also includes a water outlet pipe (19) and a mud delivery pipe (20), wherein the water outlet pipe (19) is connected to the mud discharge port (5), one end of the mud delivery pipe (20) is connected to the water outlet pipe (19), and the other end of the mud delivery pipe (20) is connected to a mud storage hopper (21), and a plurality of drainage holes (22) are provided on the water outlet pipe (19).

5. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: The pretreatment barrel (6) and the first chamber (14) are connected via an external pipe, and a valve (23) is provided on the external pipe.

6. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: The first anode plate (2) and the first cathode plate (3) are both made of lead dioxide.

7. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: The second anode plate (11) is made of carbon cloth or graphite felt, and the second cathode plate (12) is a titanium mesh having a platinum-carbon catalyst coating.

8. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: The ion exchange membrane (13) is a Nafion membrane.

9. The sludge treatment system with an integrated microbial fuel cell according to claim 1, characterized in that: The fuel tank (7) is provided with an input pipe (24) and an output pipe (25), wherein the input pipe (24) is in communication with the second chamber (15) and with an external oxygen supply, and the output pipe (25) is in communication with the first chamber (14).

10. A treatment method using the sludge treatment system with an integrated microbial fuel cell according to any one of claims 1 to 9, characterized in that: The specific steps are as follows: S1, adding chloride salt, tannic acid and sludge into the pretreatment barrel (6), mixing them through the stirring mechanism (9), and heating them through the heating mechanism (10), so as to break down the cell walls of microorganisms in the sludge and release the water and organic matter in the cells; S2. After the mixing is completed, it is transported to the first chamber (14) of the fuel chamber. The second anode plate (11) in the first chamber (14) contacts the sludge. The microorganisms oxidize the organic matter in the sludge through metabolic activities and produce electrons, protons and carbon dioxide, and transport oxygen to the second chamber. Oxygen acts as an electron acceptor. At the same time, protons pass through the ion exchange membrane (13) and combine with electrons transferred from the second cathode plate (12) through the external circuit to produce a reduction reaction to generate water. The chemical reactions between the sludge and the second anode plate (11) and between the protons and the second cathode plate (12) release electrons. The electrons flow to generate electrical energy and store it in the battery (8); S3, the treated sludge enters the sludge compression chamber (1), and the first cathode plate (3) is driven by the driving mechanism (4) to move toward the first anode plate (2). At the same time, the first anode plate (2) and the first cathode plate (3) are powered by the battery (8), and the sludge in the sludge compression chamber (1) is squeezed and electrolyzed to achieve dehydration of the sludge; S4. The dehydrated sludge enters the drainage pipe through the mud discharge port (5) below, and then enters the mud storage hopper (21) through the mud delivery pipe (20).

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