Device for recovering ammonia from wastewater through microbial electrochemical coupling conducting film

Abstract

The utility model discloses a device for recovering ammonia from waste water by a microbial electrochemical coupling conducting membrane, which belongs to the technical field of waste water treatment, and comprises a water inlet area, a conversion area and a recovery area which are sequentially arranged, a carbon fiber brush is arranged in the water inlet area, the water inlet area and the conversion area are separated by a cation exchange membrane, and the water inlet area is communicated with the conversion area. The conversion area and the recovery area are arranged in a separated mode through a conductive film. The device for recovering ammonia from wastewater by adopting the microbial electrochemical coupling conductive film disclosed by the utility model can be used for recovering ammonia nitrogen resources while realizing efficient degradation of organic matters in wastewater, is simple in structure and easy to operate, is beneficial to subsequent integrated and large-scale production and operation, has more application scenes and has a wide market prospect.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, and in particular to a device for recovering ammonia from wastewater using a microbial electrochemical coupling conductive membrane. Background Technology

[0002] Ammonia (NH3) is one of the most important raw materials for manufacturing agricultural fertilizers, chemicals, and pharmaceutical products, possessing a high energy density (4.32 kW·h·L). −1 With its high nitrogen content and hydrogen storage capacity (18%), ammonia is considered a potential renewable energy carrier. Traditional wastewater treatment plants use nitrification-denitrification or anaerobic ammonia oxidation processes to convert ammonia nitrogen into N2 for removal, which requires additional energy input and leads to the loss of bioavailable nitrogen. Considering the rapidly increasing demand for ammonia due to global population growth, recovering high-value ammonia from wastewater can significantly reduce wastewater pollution load and treatment energy consumption, while promoting the resource utilization of nitrogen in wastewater. Currently, various technologies, including stripping, struvite precipitation, and ion exchange, have been successfully used to recover ammonia from wastewater. However, these methods are energy-intensive and require the addition of additional chemicals.

[0003] Microbial electrochemical technology has been widely applied in wastewater treatment and energy resource recovery. Utilizing the extracellular electron transfer capabilities of electroactive bacteria, it directly converts the chemical energy of organic pollutants in wastewater into electrical energy or produces high-value-added products. This technology offers advantages such as being green, environmentally friendly, and low-energy consumption, making it superior to existing technologies in ammonia recovery. Currently, ammonia recovery using microbial electrochemical technology mainly relies on the electric field generated by electroactive microorganisms to drive the directional migration or diffusion of ammonium ions, thereby obtaining a high-ammonia concentrate. However, obtaining high-purity ammonia still requires combining it with recovery technologies such as stripping and struvite precipitation. Therefore, microbial electrochemical ammonia recovery technology still faces problems such as low recovery purity, low efficiency, and high cost, which urgently need to be addressed.

[0004] Membrane separation technology plays a vital role in various fields such as water treatment, food industry, biotechnology, and chemical engineering due to its high efficiency, energy saving, and environmental friendliness. Membrane technology can effectively recover and utilize resources, extracting useful substances from wastewater for reuse. In particular, the application of hydrophobic and permeable membranes in the separation of gases and volatile organic compounds shows great promise. Therefore, coupling membrane technology with microbial electrochemical techniques can overcome the challenges of low purity and low efficiency in ammonia recovery, making it an effective means of achieving wastewater resource utilization. Utility Model Content

[0005] The purpose of this invention is to provide a device for recovering ammonia from wastewater using a microbial electrochemical coupling conductive membrane. This device achieves efficient degradation of organic matter in wastewater while simultaneously recovering ammonia nitrogen resources. It has a simple structure, is easy to operate, and is conducive to subsequent integrated and large-scale production and operation. It has many applicable scenarios and a broad market prospect.

[0006] To achieve the above objectives, this utility model provides a device for recovering ammonia from wastewater using a microbial electrochemical coupling conductive membrane, comprising an inlet zone, a conversion zone, and a recovery zone arranged sequentially. The inlet zone is equipped with a carbon fiber brush. The inlet zone and the conversion zone are separated by a cation exchange membrane, and the conversion zone and the recovery zone are separated by a conductive membrane.

[0007] Preferably, the carbon fiber brush serves as the anode, with its handle extending from the side of the water inlet area away from the conversion zone and electrically connected to the electrochemical workstation; the conductive film serves as the cathode and is electrically connected to the electrochemical workstation.

[0008] Preferably, the conductive film is composed of a carbon-based conductive material and a hydrophobic and breathable membrane, wherein the carbon-based conductive material is one of carbon nanotubes and carbon cloth, and the hydrophobic and breathable membrane is one of PVDF and PTFE hydrophobic membrane.

[0009] Preferably, the top of the water inlet zone is provided with a first inlet, the top of the conversion zone is provided with a second inlet, and the top of the recovery zone is provided with a third inlet. The third inlet is connected to the feed pump and the acid chamber in sequence through pipelines, and the recovery zone is provided with an outlet on the side away from the conversion zone.

[0010] Preferably, the water inlet zone, conversion zone, and recycling zone are an integrated structure made of acrylic plexiglass.

[0011] Therefore, the device for recovering ammonia from wastewater using the above-mentioned microbial electrochemical coupling conductive membrane has the following beneficial effects:

[0012] (1) Carbon fiber brushes provide a rich loading area for electrochemically active microorganisms. The conductive membrane uses electron electrolysis of water to create an alkaline environment that converts ammonia nitrogen into ammonia gas. The separation design of the cation exchange membrane and the conductive membrane ensures the independence and functional stability of each region.

[0013] (2) By utilizing the electron and electrochemical reactions generated by microbial metabolism, the organic matter in wastewater is efficiently degraded while ammonia nitrogen resources are recovered. Furthermore, no external chemical agents are required, which reduces secondary pollution to the environment and is in line with the sustainable development concept of carbon peaking and carbon neutrality.

[0014] (3) The system has low energy consumption and low operating cost due to the constant potential provided by the electrochemical workstation, and has good economic and environmental friendliness.

[0015] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the device for recovering ammonia from wastewater using a microbial electrochemical coupling conductive membrane according to this utility model.

[0017] Figure Labels

[0018] 1. Water inlet zone; 2. Conversion zone; 3. Recovery zone; 4. Electrochemical workstation; 5. Feed pump; 6. Acid chamber; 7. Carbon fiber brush; 71. Brush handle; 8. Cation exchange membrane; 9. Conductive membrane; 10. Discharge port; 11. First feed port; 12. Second feed port; 13. Third feed port. Detailed Implementation

[0019] The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments.

[0020] Unless otherwise defined, the technical or scientific terms used in this utility model shall have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar terms used in this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0021] Example 1

[0022] like Figure 1 As shown, this utility model provides a device for recovering ammonia from wastewater using a microbial electrochemical coupling conductive membrane, comprising an inlet zone 1, a conversion zone 2, and a recovery zone 3 arranged sequentially. The inlet zone 1, conversion zone 2, and recovery zone 3 are an integral structure made of acrylic plexiglass, which facilitates observation of the internal reaction and maintenance.

[0023] A first feed inlet 11 is provided at the top of the inlet zone 1, through which wastewater enters the inlet zone 1. A carbon fiber brush 7 is installed inside the inlet zone 1, serving as the anode. Its handle 71 extends from the side of the inlet zone 1 away from the conversion zone 2 and is electrically connected to the electrochemical workstation 4. The carbon fiber brush 7 is used to load electroactive microorganisms, and the electrochemical workstation 4 provides voltage to provide the necessary growth conditions for the electroactive microorganisms. The electroactive microorganisms metabolize and degrade organic matter in the wastewater, generating electrons.

[0024] The influent zone 1 and the conversion zone 2 are separated by a cation exchange membrane 8, which maintains an alkaline environment in the conversion zone 2 and converts ammonium nitrogen into gaseous ammonia. A second inlet 12 is located at the top of the conversion zone 2, through which sodium sulfate solution enters the conversion zone 2. Sodium sulfate plays multiple roles in the system, including adjusting pH, providing electrolytes, participating in chemical reactions, and promoting microbial activity, thus contributing to improved ammonia nitrogen removal efficiency.

[0025] Conversion zone 2 and recovery zone 3 are separated by a conductive membrane 9. The conductive membrane 9 acts as a cathode and is electrically connected to the electrochemical workstation 4. It utilizes electrons generated at the anode to electrolyze water, thus providing an alkaline environment and driving force for ammonia migration. The conductive membrane 9 is composed of a carbon-based conductive material (carbon nanotubes) and a hydrophobic and breathable membrane (PVDF). It possesses excellent conductivity and hydrophobicity, effectively preventing interpenetration of liquids in conversion zone 2 and recovery zone 3, ensuring the long-term stable operation of the reaction system. The preparation process of the conductive membrane 9 includes: 10-20 g / m³ of... 2 Carbon nanotubes were loaded onto the surface of a PVDF hydrophobic membrane through filtration, cross-linking, and drying.

[0026] The top of the recovery zone 3 is equipped with a third inlet 13, which is connected to the feed pump 5 and the acid chamber 6 via pipelines. Sulfuric acid solution enters the recovery zone 3 from the acid chamber 6 through the feed pump 5 and the third inlet 13, converting gaseous ammonia into ammonium sulfate. The recovery zone 3 is equipped with an outlet 10 on the side away from the conversion zone 2, through which liquid ammonium sulfate can be effectively recovered.

[0027] Working Principle: First, wastewater containing organic matter and ammonia nitrogen enters the influent zone 1 through the first inlet 11. Sodium sulfate solution enters the conversion zone 2 through the second inlet 12, and sulfuric acid solution enters the recovery zone 3 from the acid chamber 6 through the feed pump 5 and the third inlet 13. Subsequently, a constant potential of 0.5-0.7V is applied between the anode and cathode by the electrochemical workstation 4, causing electroactive microorganisms to be directionally enriched on the carbon fiber brush 7. The electroactive microorganisms metabolize and degrade the organic matter in the wastewater, generating electrons, which are transferred to the conductive membrane 9 through an external circuit. The conductive membrane 9 uses the electrons generated at the anode to electrolyze water, generating hydroxide ions in the conversion zone 2 to create an alkaline environment. Driven by the electric field generated by the electroactive microorganisms, ammonia nitrogen in the influent zone 1 migrates across the cation exchange membrane 8 to the conversion zone 2 and the conductive membrane 9, combines with hydroxide ions, and then passes through the conductive membrane 9 in the form of ammonia gas into the recovery zone 3. The recovery zone 3 uses a 0.1-0.4mol / L sulfuric acid solution to absorb the ammonia gas, finally converting the ammonia into high-purity ammonium sulfate, which is then recovered through the outlet 10.

[0028] Therefore, this utility model uses the above-mentioned device for recovering ammonia from wastewater by microbial electrochemical coupling conductive membrane, which realizes efficient degradation of organic matter in wastewater while recovering ammonia nitrogen resources. It has a simple structure, is easy to operate, and is conducive to subsequent integrated and large-scale production and operation. It has many applicable scenarios and broad market prospects.

[0029] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solution of this utility model, and these modifications or equivalent substitutions cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of this utility model.

Claims

1. A device for recovering ammonia from wastewater using a microbial electrochemically coupled conductive membrane, characterized in that: It includes an inlet water zone, a conversion zone, and a recycling zone arranged in sequence. The inlet water zone is equipped with a carbon fiber brush. The inlet water zone and the conversion zone are separated by a cation exchange membrane, and the conversion zone and the recycling zone are separated by a conductive membrane.

2. The device for recovering ammonia from wastewater using a microbial electrochemically coupled conductive membrane according to claim 1, characterized in that: The carbon fiber brush serves as the anode, with its handle extending from the side of the water inlet area away from the conversion zone and electrically connected to the electrochemical workstation; the conductive film serves as the cathode and is electrically connected to the electrochemical workstation.

3. The device for recovering ammonia from wastewater using a microbial electrochemical coupling conductive membrane according to claim 1, characterized in that: The conductive film is composed of a carbon-based conductive material and a hydrophobic and breathable membrane. The carbon-based conductive material is one of carbon nanotubes and carbon cloth, and the hydrophobic and breathable membrane is one of PVDF and PTFE hydrophobic membrane.

4. The device for recovering ammonia from wastewater using a microbial electrochemically coupled conductive membrane according to claim 1, characterized in that: The water inlet zone is provided with a first inlet at the top, the conversion zone is provided with a second inlet at the top, and the recovery zone is provided with a third inlet at the top. The third inlet is connected to the feed pump and the acid chamber in sequence through pipes. The recovery zone is provided with an outlet on the side away from the conversion zone.

5. The device for recovering ammonia from wastewater using a microbial electrochemically coupled conductive membrane according to claim 1, characterized in that: The water inlet zone, conversion zone, and recycling zone are an integrated structure made of acrylic plexiglass.

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