An ammonia-nitrogen recovery device and method based on electrodialysis and coupled reverse osmosis membrane

Abstract

The application relates to a device and a method for recovering ammonia nitrogen based on electrodialysis and coupling reverse osmosis membranes, and relates to the field of water treatment. The device for recovering ammonia nitrogen based on electrodialysis and coupling reverse osmosis membranes comprises a cathode chamber, a product chamber, an anode chamber, a feed storage chamber, a pure water storage chamber, an electrode liquid storage chamber, a residual liquid collecting chamber, an ammonia liquid collecting chamber, an anode chamber effluent collecting chamber, a reverse osmosis membrane, a proton exchange membrane, a cathode electrode plate, an anode electrode plate, a screen, a gasket and a power supply. The device combines the double advantages of electrodialysis and reverse osmosis membrane technology, can efficiently recover ammonia nitrogen by using electrochemical reaction without adding chemical additives, can realize efficient recovery of ammonia nitrogen by electrodialysis coupling reverse osmosis membranes under a certain current density, and the recovery rate of ammonia nitrogen can reach 92.31%, and secondary pollution is reduced. In addition, the device has the advantages of simple structure, low cost, suitability for industrial application and good market promotion prospect.

Description

Technical Field

[0001] This invention relates to the field of water treatment, and specifically to an ammonia nitrogen recovery device and method based on electrodialysis and coupled reverse osmosis membrane. Background Technology

[0002] In existing technologies, common methods for nitrogen resource recovery include ammonia stripping, ion exchange, and membrane methods. Ammonia stripping is simple to operate and has low equipment costs, but it consumes a lot of energy and requires subsequent treatment of the released ammonia, which may cause secondary pollution. Ion exchange can selectively remove and recover ammonia nitrogen from wastewater, suitable for wastewater with varying concentrations of ammonia nitrogen. However, this technology faces challenges due to the limited lifespan of ion exchange resins and the frequent regeneration requirements, which can increase operational complexity and costs. Furthermore, its processing capacity is limited by the selectivity and flux of the membrane. While membrane technologies such as reverse osmosis can effectively recover ammonia nitrogen under low-energy conditions, they face membrane clogging and aging problems when treating high-concentration ammonia nitrogen wastewater, severely impacting their lifespan and economic efficiency.

[0003] To address the shortcomings of the above methods, electrodialysis technology, due to its unique treatment mechanism and excellent separation effect, has gradually become a more efficient, economical, and environmentally friendly alternative solution. Electrodialysis is a separation process that utilizes an electric field to allow charged particles to penetrate a semi-permeable membrane, effectively recovering dissolved inorganic salts and organic matter from wastewater. However, electrodialysis alone still faces problems of insufficient efficiency and excessive energy consumption when treating certain high-concentration pollutants, especially ammonia nitrogen. Therefore, it is necessary to explore a high-efficiency ammonia nitrogen recovery device and method that is simple in construction, low in economic cost, has low membrane fouling tendency, and low energy consumption. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention provides an ammonia nitrogen recovery device and method based on electrodialysis and coupled reverse osmosis membrane.

[0005] This invention combines the advantages of both electrodialysis and reverse osmosis membrane technologies, enabling efficient recovery of ammonia nitrogen through electrochemical reactions without the need for chemical additives, thus reducing secondary pollution. Furthermore, the device is simple in structure, low in cost, suitable for industrial applications, and has promising market prospects.

[0006] An ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane includes a cathode chamber 1, a product chamber 2, an anode chamber 3, a feed storage chamber 4, a pure water storage chamber 5, an electrode solution storage chamber 6, a residual liquid collection chamber 7, an ammonia solution collection chamber 8, an anode chamber effluent collection chamber 9, a reverse osmosis membrane 10, a proton exchange membrane 11, a cathode electrode plate 12, an anode electrode plate 13, a separator, a gasket, and a power supply.

[0007] The negative terminal of the power supply is connected to the cathode electrode plate 12, and the positive terminal is connected to the anode electrode plate 13. A reverse osmosis membrane 10 and a proton exchange membrane 11 are disposed between the cathode electrode plate 12 and the anode electrode plate 13. The reverse osmosis membrane 10 is disposed between the separator and the gasket. The space formed between the cathode electrode plate 12 and the reverse osmosis membrane 10 is the cathode chamber 1. The space formed between the reverse osmosis membrane 10 and the proton exchange membrane 11 is the product chamber 2. The space formed between the proton exchange membrane 11 and the anode electrode plate 13 is the anode chamber 3.

[0008] The feed storage chamber 4 and the residual liquid collection chamber 7 are respectively connected to the cathode chamber 1;

[0009] The pure water storage chamber 5 and the ammonia collection chamber 8 are respectively connected to the product chamber 2;

[0010] The electrode liquid storage chamber 6 and the anode chamber effluent collection chamber 9 are respectively connected to the anode chamber 3.

[0011] A method for ammonia nitrogen recovery based on electrodialysis and coupled reverse osmosis membranes is implemented using an ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membranes, and specifically includes the following steps:

[0012] Ammonia-containing wastewater from feed storage chamber 4 is introduced into cathode chamber 1 via a peristaltic pump, pure water from pure water storage chamber 5 is introduced into product chamber 2, and Na2SO4 solution from electrode liquid storage chamber 6 is introduced into anode chamber 3. Cathode electrode plate 12 and anode electrode plate 13 are connected to the negative and positive terminals of the power supply, respectively, and a constant voltage mode or constant current mode is applied to cathode electrode plate 12 and anode electrode plate 13.

[0013] Redox reactions occur on cathode electrode plate 12 and anode electrode plate 13, with OH- being generated on cathode electrode plate 12. - The anode electrode plate 13 generates H + Under the influence of an electric field, OH- is generated in cathode chamber 1. - This causes the ammonium ions (NH4+) in ammonia nitrogen-containing wastewater to increase. + It is converted into free ammonia (NH3);

[0014] The NH3 generated in cathode chamber 1 rapidly permeates through the reverse osmosis membrane 10 into product chamber 2, while other cations in the ammonia-nitrogen-containing wastewater are retained on the cathode electrode plate 12 side of product chamber 2 under the action of the electric field coupled to the reverse osmosis membrane, thereby reducing the fouling tendency of the reverse osmosis membrane 10 and extending its service life. Anions in cathode chamber 1 migrate into product chamber 2 under the action of the electric field. Since the reverse osmosis membrane 10 has a high rejection rate for divalent anions, monovalent anions permeate through the reverse osmosis membrane 10 into product chamber 2 to maintain charge balance. The residual liquid generated in cathode chamber 1 is collected in residual liquid collection chamber 7 for subsequent treatment.

[0015] H generated in anode chamber 3 + Under the influence of an electric field, NH3 diffuses through proton exchange membrane 11 into product chamber 2, converting NH3 back into NH4. - The effluent from product chamber 2 is a pure NH4Cl ammonia solution, which is collected in ammonia collection chamber 8; the effluent from anode chamber 3 is collected in anode chamber effluent collection chamber 9 and can be recycled back to anode chamber 3 for reuse.

[0016] Technical features and beneficial effects of the present invention:

[0017] I. The present invention provides an ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane, which combines the dual advantages of electrodialysis and reverse osmosis membrane technologies, effectively improving the recovery efficiency of ammonia nitrogen. Through electrodialysis technology, the device can selectively migrate ions in wastewater under low energy consumption conditions, while reverse osmosis membrane technology can efficiently retain salt ions. The synergistic effect of the two makes the extraction of ammonia nitrogen more efficient and pure.

[0018] II. This invention discloses an ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membranes, which utilizes an electrochemical reaction to directly generate OH in cathode chamber 1. - This process converts ammonium ions in ammonia-nitrogen-containing wastewater into free ammonia. The free ammonia permeates through the reverse osmosis membrane 10 and enters the product chamber 2, where it reacts with the H2O generated at the anode. + The conversion of ammonia ions into ammonium ions optimizes the ammonia nitrogen recovery process and reduces the reliance on chemical reagents and potential secondary pollution. Furthermore, the adsorption of cations by the electrode plates in the cathode chamber 1 helps reduce the accumulation of hardness ions such as calcium and magnesium on the reverse osmosis membrane surface, effectively extending the service life of the reverse osmosis membrane 10. In summary, the device of this invention has a simple structure, partially replaces expensive anion and cation exchange membranes with the reverse osmosis membrane 10, and is economically cost-effective and highly feasible. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of an ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane in this invention;

[0020] Figure 2 This is a schematic diagram of the ammonia nitrogen recovery method based on electrodialysis and coupled reverse osmosis membrane in this invention.

[0021] Figure 3 This is a graph showing the change in ammonia nitrogen concentration in the product chamber in Example 2. Detailed Implementation

[0022] The technical solution of the device of the present invention will be further described below through a specific implementation example. In this example, the ammonia nitrogen wastewater used is landfill leachate. Before entering this device, the raw landfill leachate is pretreated to remove organic matter. The description of this embodiment is only for further illustrating the features and advantages of the present invention, and is not intended to limit the scope of the claims of the present invention.

[0023] Specific Implementation Method 1: This implementation method is an ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane, including a cathode chamber 1, a product chamber 2, an anode chamber 3, a feed storage chamber 4, a pure water storage chamber 5, an electrode liquid storage chamber 6, a residual liquid collection chamber 7, an ammonia liquid collection chamber 8, an anode chamber effluent collection chamber 9, a reverse osmosis membrane 10, a proton exchange membrane 11, a cathode electrode plate 12, an anode electrode plate 13, a separator, a gasket, and a power supply;

[0024] The negative terminal of the power supply is connected to the cathode electrode plate 12, and the positive terminal is connected to the anode electrode plate 13. A reverse osmosis membrane 10 and a proton exchange membrane 11 are disposed between the cathode electrode plate 12 and the anode electrode plate 13. The reverse osmosis membrane 10 is disposed between the separator and the gasket. The space formed between the cathode electrode plate 12 and the reverse osmosis membrane 10 is the cathode chamber 1. The space formed between the reverse osmosis membrane 10 and the proton exchange membrane 11 is the product chamber 2. The space formed between the proton exchange membrane 11 and the anode electrode plate 13 is the anode chamber 3.

[0025] The feed storage chamber 4 and the residual liquid collection chamber 7 are respectively connected to the cathode chamber 1;

[0026] The pure water storage chamber 5 and the ammonia collection chamber 8 are respectively connected to the product chamber 2;

[0027] The electrode liquid storage chamber 6 and the anode chamber effluent collection chamber 9 are respectively connected to the anode chamber 3.

[0028] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that: a peristaltic pump is installed on the pipeline connecting the feed storage chamber 4 and the cathode chamber 1; a peristaltic pump is installed on the pipeline connecting the pure water storage chamber 5 and the product chamber 2; and a peristaltic pump is installed on the pipeline connecting the electrode liquid storage chamber 6 and the anode chamber 3. The other steps are the same as in Specific Implementation Method One.

[0029] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the cathode electrode plate 12 and anode electrode plate 13 are made of metal electrodes, non-metal electrodes, or doped and modified electrodes. The other steps are the same as in Specific Implementation Method One or Two.

[0030] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that: the metal electrode includes an Ir electrode, a Ru electrode, a Pt electrode, or a ruthenium-iridium electrode; the non-metal electrode is a graphite electrode; and the doped and modified electrode is an electrode obtained by doping and modifying an Ir electrode, a Ru electrode, or a graphite electrode. Other steps are the same as in Specific Implementation Methods One to Three.

[0031] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the distance between the cathode electrode plate 12 and the anode electrode plate 13 is 0.5cm to 2.0cm. The other steps are the same as in Specific Implementation Methods One to Four.

[0032] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that: the proton exchange membrane 11 is a perfluorosulfonic acid type proton exchange membrane; the reverse osmosis membrane 10 is a commercial polyamide reverse osmosis composite membrane BW30XLE, which consists of three parts: a PA layer, a support layer, and a non-woven fabric, wherein the thickness of the PA layer is 100nm to 200nm. Other steps are the same as in Specific Implementation Methods One to Five.

[0033] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that: the ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane is a closed device; and the voltage applied by the power supply is greater than 1.23V. Other steps are the same as in Specific Implementation Methods One to Six.

[0034] Specific Implementation Method Eight: This implementation method for ammonia nitrogen recovery based on electrodialysis and coupled reverse osmosis membranes is accomplished using an ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membranes, and specifically includes the following steps:

[0035] Ammonia-containing wastewater from feed storage chamber 4 is introduced into cathode chamber 1 via a peristaltic pump, pure water from pure water storage chamber 5 is introduced into product chamber 2, and Na2SO4 solution from electrode liquid storage chamber 6 is introduced into anode chamber 3. Cathode electrode plate 12 and anode electrode plate 13 are connected to the negative and positive terminals of the power supply, respectively, and a constant voltage mode or constant current mode is applied to cathode electrode plate 12 and anode electrode plate 13.

[0036] Redox reactions occur on cathode electrode plate 12 and anode electrode plate 13, with OH- being generated on cathode electrode plate 12. - The anode electrode plate 13 generates H + Under the influence of an electric field, OH- is generated in cathode chamber 1. - This causes the ammonium ions (NH4+) in ammonia nitrogen-containing wastewater to increase. + It is converted into free ammonia (NH3);

[0037] The NH3 generated in cathode chamber 1 rapidly permeates through the reverse osmosis membrane 10 into product chamber 2, while other cations in the ammonia-nitrogen-containing wastewater are retained on the cathode electrode plate 12 side of product chamber 2 under the action of the electric field coupled to the reverse osmosis membrane, thereby reducing the fouling tendency of the reverse osmosis membrane 10 and extending its service life. Anions in cathode chamber 1 migrate into product chamber 2 under the action of the electric field. Since the reverse osmosis membrane 10 has a high rejection rate for divalent anions, monovalent anions permeate through the reverse osmosis membrane 10 into product chamber 2 to maintain charge balance. The residual liquid generated in cathode chamber 1 is collected in residual liquid collection chamber 7 for subsequent treatment.

[0038] H generated in anode chamber 3 + Under the influence of an electric field, NH3 diffuses through proton exchange membrane 11 into product chamber 2, converting NH3 back into NH4. - The effluent from product chamber 2 is a pure NH4Cl ammonia solution, which is collected in ammonia collection chamber 8; the effluent from anode chamber 3 is collected in anode chamber effluent collection chamber 9 and can be recycled back to anode chamber 3 for reuse.

[0039] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that: the ammonia-nitrogen-containing wastewater mentioned in step one is domestic sewage or landfill leachate; the concentration of ammonia nitrogen in the domestic sewage is 40 mg / L to 70 mg / L, and the concentration of ammonia nitrogen in the landfill leachate is 600 mg / L to 800 mg / L; the concentration of the Na₂SO₄ solution is 0.1 mol / L. The other steps are the same as in Specific Implementation Methods One to Eight.

[0040] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One to Nine in that: the pH value of the ammonia-nitrogen-containing wastewater described in step one is 3-12; when the ammonia-nitrogen-containing wastewater is acidic or neutral, the OH generated by the cathode electrode plate 12... - This allows ammonium ions to be converted into free ammonia, which then permeates through the reverse osmosis membrane 10. When the ammonia-containing wastewater is alkaline, the free ammonia in the wastewater can directly permeate through the reverse osmosis membrane 10. Other steps are the same as in specific implementation methods one through nine.

[0041] The beneficial effects of the present invention are verified using the following embodiments:

[0042] Example 1: An ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane, such as Figure 1 As shown, it includes a cathode chamber 1, a product chamber 2, an anode chamber 3, a feed storage chamber 4, a pure water storage chamber 5, an electrode solution storage chamber 6, a residual liquid collection chamber 7, an ammonia liquid collection chamber 8, an anode chamber effluent collection chamber 9, a reverse osmosis membrane 10 (RO), a proton exchange membrane 11 (PEM), a cathode electrode plate 12, an anode electrode plate 13, a separator, gaskets, and a power supply.

[0043] Feed storage chamber 4 is used to store the ammonia nitrogen-containing wastewater required in cathode chamber 1;

[0044] Pure water storage chamber 5 is used to store the pure water required by product chamber 2;

[0045] Electrode solution storage chamber 6 is used to store the electrode solution (sodium sulfate solution) required in anode chamber 3;

[0046] The residual liquid collection chamber 7 is used to collect the effluent from the cathode chamber 1 for subsequent processing;

[0047] Ammonia collection chamber 8 is used to collect the effluent from product chamber 2, thereby realizing nitrogen resource recovery;

[0048] Anode chamber effluent collection chamber 9 is used to collect and store the effluent from anode chamber 3 for reuse;

[0049] The screen serves two purposes: firstly, it ensures uniform water distribution, allowing ammonia-nitrogen-containing wastewater to be evenly distributed on the surface of the reverse osmosis membrane 10; secondly, it increases the shear velocity on the membrane surface, maintaining the liquid flow in the cathode chamber 1 in a turbulent state.

[0050] Gaskets are used to assist in collecting the effluent from product chamber 2;

[0051] A peristaltic pump is used to connect the inlet pipes of cathode chamber 1, product chamber 2, and anode chamber 3 to control the water inlet and flow rate of the electrode chambers.

[0052] A power supply is used to connect the cathode electrode plate 12 and the anode electrode plate 13. The power supply applies voltage, which on the one hand creates an electric field between the cathode electrode plate 12 and the anode electrode plate 13 to control the direction of migration of cations and anions in different electrode chambers; on the other hand, the application of the external voltage causes redox reactions (such as water electrolysis) to occur on the cathode and anode electrode plates, producing OH-. - and H + This, in turn, regulates the form transformation of ammonia nitrogen between free ammonia and ammonium ions;

[0053] A reverse osmosis membrane 10 is used to allow free ammonia to diffuse rapidly across the membrane while retaining salt ions, wherein the active layer of the reverse osmosis membrane is exposed in the cathode chamber 1;

[0054] The proton exchange membrane 11 is used to conduct protons while blocking other ions (such as sodium ions);

[0055] The negative terminal of the power supply is connected to the cathode electrode plate 12, and the positive terminal is connected to the anode electrode plate 13. A reverse osmosis membrane 10 and a proton exchange membrane 11 are disposed between the cathode electrode plate 12 and the anode electrode plate 13. The reverse osmosis membrane 10 is disposed between the separator and the gasket. The space formed between the cathode electrode plate 12 and the reverse osmosis membrane 10 is the cathode chamber 1. The space formed between the reverse osmosis membrane 10 and the proton exchange membrane 11 is the product chamber 2. The space formed between the proton exchange membrane 11 and the anode electrode plate 13 is the anode chamber 3.

[0056] The feed storage chamber 4 and the residual liquid collection chamber 7 are respectively connected to the cathode chamber 1;

[0057] The pure water storage chamber 5 and the ammonia collection chamber 8 are respectively connected to the product chamber 2;

[0058] The electrode liquid storage chamber 6 and the anode chamber effluent collection chamber 9 are respectively connected to the anode chamber 3;

[0059] A peristaltic pump is installed on the pipeline connecting the feed storage chamber 4 and the cathode chamber 1; a peristaltic pump is installed on the pipeline connecting the pure water storage chamber 5 and the product chamber 2; a peristaltic pump is installed on the pipeline connecting the electrode liquid storage chamber 6 and the anode chamber 3.

[0060] The cathode electrode plate 12 is made of ruthenium-iridium electrode material;

[0061] The anode electrode plate 13 is made of ruthenium-iridium electrode.

[0062] The distance between the cathode electrode plate 12 and the anode electrode plate 13 is 1.5 cm;

[0063] The proton exchange membrane 11 is a perfluorosulfonic acid type proton exchange membrane, and the effective area of ​​the membrane is 5cm×7cm; the reverse osmosis membrane 10 is a commercial polyamide reverse osmosis composite membrane BW30XLE, which is composed of three parts: PA layer, support layer and non-woven fabric, wherein the thickness of PA layer is 100nm.

[0064] The ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane is a closed device.

[0065] Example 2: An ammonia nitrogen recovery method based on electrodialysis and coupled reverse osmosis membrane is implemented using the ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane described in Example 1, and specifically includes the following steps:

[0066] Ammonia-containing wastewater from feed storage chamber 4 is introduced into cathode chamber 1 via a peristaltic pump. Pure water from pure water storage chamber 5 is introduced into product chamber 2. A 0.1 mol / L Na₂SO₄ solution from electrode solution storage chamber 6 is introduced into anode chamber 3. Cathode electrode plate 12 and anode electrode plate 13 are connected to the negative and positive terminals of a power supply, respectively. A constant current mode with a current density of 15 mA / cm² is applied to cathode electrode plate 12 and anode electrode plate 13. 2 ;

[0067] Redox reactions occur on cathode electrode plate 12 and anode electrode plate 13, with OH- being generated on cathode electrode plate 12. - The anode electrode plate 13 generates H + Under the influence of an electric field, OH- is generated in cathode chamber 1. - This causes the ammonium ions (NH4+) in ammonia nitrogen-containing wastewater to increase. + 4) It is converted into free ammonia (NH3);

[0068] The NH3 generated in cathode chamber 1 rapidly permeates through the reverse osmosis membrane 10 into product chamber 2, while other cations in the ammonia-nitrogen-containing wastewater are retained on the cathode electrode plate 12 side of product chamber 2 under the action of the electric field coupled to the reverse osmosis membrane, thereby reducing the fouling tendency of the reverse osmosis membrane 10 and extending its service life. Anions in cathode chamber 1 migrate into product chamber 2 under the action of the electric field. Since the reverse osmosis membrane 10 has a high rejection rate for divalent anions, monovalent anions permeate through the reverse osmosis membrane 10 into product chamber 2 to maintain charge balance. The residual liquid generated in cathode chamber 1 is collected in residual liquid collection chamber 7 for subsequent treatment.

[0069] H generated in anode chamber 3 + Under the influence of an electric field, NH3 diffuses through proton exchange membrane 11 into product chamber 2, converting NH3 back into NH4. + The effluent from product chamber 2 is a pure NH4Cl ammonia solution, which is collected in ammonia collection chamber 8; the effluent from anode chamber 3 is collected in anode chamber effluent collection chamber 9 and can be recycled back to anode chamber 3 for reuse.

[0070] The ammonia nitrogen-containing wastewater mentioned in step one is landfill leachate. Before entering this device, the raw landfill leachate is pretreated to remove organic matter, with a pH value of 6.9±0.05, an ammonia nitrogen concentration range of 650mg / L, and an electrical conductivity of approximately 29mS / cm.

[0071] The shear flow rate on the surface of the reverse osmosis membrane 10 is controlled to be 20 L / h using a peristaltic pump;

[0072] The total operating time of the device was 100 minutes. Ammonia nitrogen concentration in product chamber 2 was measured every 25 minutes. The resulting graph showed the changes in ammonia nitrogen concentration in product chamber 2 over different operating times. Figure 3 As shown;

[0073] Figure 3 The graph shows the change in ammonia nitrogen concentration in the product chamber in Example 2. The results show that the device of the present invention can achieve efficient ammonia nitrogen recovery through electrodialysis coupled with reverse osmosis membrane under a certain current density, and the ammonia nitrogen recovery rate can reach 92.31%.

Claims

1. An ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane, characterized in that... The device includes a cathode chamber (1), a product chamber (2), an anode chamber (3), a feed storage chamber (4), a pure water storage chamber (5), an electrode liquid storage chamber (6), a residual liquid collection chamber (7), an ammonia liquid collection chamber (8), an anode chamber effluent collection chamber (9), a reverse osmosis membrane (10), a proton exchange membrane (11), a cathode electrode plate (12), an anode electrode plate (13), a mesh, gaskets, and a power supply; The negative terminal of the power supply is connected to the cathode electrode plate (12), and the positive terminal is connected to the anode electrode plate (13). A reverse osmosis membrane (10) and a proton exchange membrane (11) are provided between the cathode electrode plate (12) and the anode electrode plate (13). The reverse osmosis membrane (10) is disposed between the separator and the gasket. The space formed between the cathode electrode plate (12) and the reverse osmosis membrane (10) is the cathode chamber (1). The space formed between the reverse osmosis membrane (10) and the proton exchange membrane (11) is the product chamber (2). The space formed between the proton exchange membrane (11) and the anode electrode plate (13) is the anode chamber (3). The feed storage chamber (4) and the residual liquid collection chamber (7) are respectively connected to the cathode chamber (1); The pure water storage chamber (5) and the ammonia collection chamber (8) are respectively connected to the product chamber (2); The electrode liquid storage chamber (6) and the anode chamber effluent collection chamber (9) are respectively connected to the anode chamber (3).

2. The ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane according to claim 1, characterized in that... A peristaltic pump is installed on the pipeline connecting the feed storage chamber (4) and the cathode chamber (1); a peristaltic pump is installed on the pipeline connecting the pure water storage chamber (5) and the product chamber (2); a peristaltic pump is installed on the pipeline connecting the electrode liquid storage chamber (6) and the anode chamber (3).

3. The ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane according to claim 1, characterized in that... The cathode electrode plate (12) and anode electrode plate (13) are made of metal electrodes, non-metal electrodes or doped and modified electrodes.

4. The ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane according to claim 3, characterized in that... The metal electrode includes an Ir electrode, a Ru electrode, a Pt electrode, or a ruthenium-iridium electrode; the non-metal electrode is a graphite electrode; and the doped and modified electrode is an electrode obtained by doping and modifying an Ir electrode, a Ru electrode, or a graphite electrode.

5. An ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane according to claim 1, characterized in that... The distance between the cathode electrode plate (12) and the anode electrode plate (13) is 0.5cm to 2.0cm.

6. An ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane according to claim 1, characterized in that... The proton exchange membrane (11) is a perfluorosulfonic acid type proton exchange membrane; the reverse osmosis membrane (10) is a commercial polyamide reverse osmosis composite membrane BW30XLE, which consists of three parts: a PA layer, a support layer and a non-woven fabric, wherein the thickness of the PA layer is 100nm~200nm.

7. An ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane according to claim 1, characterized in that... The ammonia nitrogen recovery device based on electrodialysis and coupled reverse osmosis membrane is a closed device; the voltage applied by the power supply is greater than 1.23V.

8. A method for ammonia nitrogen recovery based on electrodialysis and coupled reverse osmosis membrane, characterized in that... The method is performed using the apparatus described in any one of claims 1 to 7, and specifically includes the following steps: Ammonia-containing wastewater from the feed storage chamber (4) is introduced into the cathode chamber (1) by a peristaltic pump, pure water from the pure water storage chamber (5) is introduced into the product chamber (2), and Na2SO4 solution from the electrode liquid storage chamber (6) is introduced into the anode chamber (3). The cathode electrode plate (12) and the anode electrode plate (13) are connected to the negative and positive terminals of the power supply, respectively. A constant voltage mode or a constant current mode is applied to the cathode electrode plate (12) and the anode electrode plate (13). A redox reaction occurs on the cathode electrode plate (12) and the anode electrode plate (13), and OH- is generated on the cathode electrode plate (12). - H is generated by the anode electrode plate (13). + Under the influence of an electric field, OH- is generated in the cathode chamber (1). - This causes the NH4 in ammonia nitrogen-containing wastewater to increase. + Converted to NH3; The NH3 generated in the cathode chamber (1) rapidly permeates through the reverse osmosis membrane (10) into the product chamber (2), while other cations in the ammonia nitrogen-containing wastewater are retained on the cathode electrode plate (12) side of the product chamber (2) under the action of the electric field coupled to the reverse osmosis membrane, thereby reducing the fouling tendency of the reverse osmosis membrane (10) and extending the service life of the reverse osmosis membrane (10); the anions in the cathode chamber (1) migrate into the product chamber (2) under the action of the electric field. Since the reverse osmosis membrane (10) has a high retention of divalent anions, monovalent anions permeate through the reverse osmosis membrane (10) into the product chamber (2) to maintain charge balance; the residual liquid generated in the cathode chamber (1) is collected in the residual liquid collection chamber (7) for subsequent treatment; H generated in the anode chamber (3) + Under the influence of an electric field, the NH3 diffuses through the proton exchange membrane (11) into the product chamber (2), converting NH3 back into NH4. + The effluent from the product chamber (2) is a pure NH4Cl ammonia solution, which is collected in the ammonia collection chamber (8); the effluent from the anode chamber (3) is collected in the anode chamber effluent collection chamber (9) and can be recycled back to the anode chamber (3) for reuse.

9. The ammonia nitrogen recovery method based on electrodialysis and coupled reverse osmosis membrane according to claim 8, characterized in that... The ammonia nitrogen-containing wastewater mentioned in step one is domestic sewage or landfill leachate; the concentration of ammonia nitrogen in the domestic sewage is 40 mg / L to 70 mg / L, and the concentration of ammonia nitrogen in the landfill leachate is 600 mg / L to 800 mg / L; the concentration of the Na2SO4 solution is 0.1 mol / L.

10. The ammonia nitrogen recovery method based on electrodialysis and coupled reverse osmosis membrane according to claim 8, characterized in that... The pH value of the ammonia-nitrogen-containing wastewater mentioned in step one is 3~12; when the ammonia-nitrogen-containing wastewater is acidic or neutral, the OH generated by the cathode electrode plate (12) - This allows ammonium ions to be converted into free ammonia and permeate the reverse osmosis membrane (10); when the ammonia-containing wastewater is alkaline, the free ammonia in the ammonia-containing wastewater can directly permeate the reverse osmosis membrane (10).

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