Device for recovering ammonium sulfate through electrocatalytic reduction and using method thereof

Abstract

The invention discloses a device for recovering ammonium sulfate through electrocatalytic reduction and a using method thereof.The device comprises a wastewater pool and an outer shell, a physical filtering bin is fixedly installed in the outer shell, a water inlet of the physical filtering bin is communicated with the wastewater pool, and a water outlet of the physical filtering bin is fixedly connected with a closed electrolytic tank; the upper end of the closed electrolytic tank is fixedly connected with an electrochemical workstation, the lower end surface of the closed electrolytic tank is fixedly provided with a lead-out port, the lead-out port is fixedly connected with a product recovery device, the product recovery device comprises a first chamber and a second chamber, and a gas diffusion port is formed between the first chamber and the second chamber; a gas diffusion film is fixedly installed in the gas diffusion opening, a product discharging opening is fixedly formed in the second cavity, a product discharging valve is fixedly installed at the product discharging opening, and the nitrate reduction device is simple in structure and convenient to use, and the nitrate reduction efficiency is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of electrocatalysts, and in particular to a device for recovering ammonium sulfate by electrocatalytic reduction and a method for using the device. Background Art

[0002] Nitrate is the most highly oxidized form of nitrogen and exists in natural water bodies and various types of industrial wastewater. Excessive nitrate in the environment can lead to eutrophication of water, which in turn affects human health. NO3- is converted into nitrite anions in the human body, which is closely related to various adverse health consequences, including liver damage, colorectal cancer, bladder cancer, breast cancer and thyroid disease. At present, various treatment technologies for removing NO3- from water are very common, including physical adsorption, biological denitrification, electrodialysis, ion exchange, reverse osmosis and catalytic hydrogenation, but these technologies all have certain disadvantages, such as low reaction efficiency, high operating costs, and serious influence of environmental conditions. The selective electrocatalytic reduction of nitrate to NH3 using renewable electricity is attracting considerable research interest because it requires relatively simple operating conditions and less energy loss and does not produce sludge. More attractively, the NH3 produced in NO3- can be recycled as a value-added product, such as (NH4)2SO4 fertilizer.

[0003] Ammonium sulfate is a physiologically acidic fertilizer with broad application prospects in agriculture. It is suitable for general soils and crops. It can make branches and leaves grow vigorously, improve fruit quality and yield, and enhance the resistance of crops to disasters. It can be used as base fertilizer, topdressing and seed fertilizer. Summary of the invention

[0004] The main purpose of the present invention is to provide a device for recovering ammonium sulfate by electrocatalytic reduction.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A device for recovering ammonium sulfate by electrocatalytic reduction comprises a wastewater tank and an outer shell, wherein a physical filter bin is fixedly installed in the outer shell, a water inlet of the physical filter bin is connected to the wastewater tank, a water outlet of the physical filter bin is fixedly connected to a closed electrolytic cell, an upper end of the closed electrolytic cell is fixedly connected to an electrochemical workstation, a lower end surface of the closed electrolytic cell is fixedly provided with a guide outlet, a product recovery device is fixedly connected to the guide outlet, the product recovery device comprises a first chamber and a second chamber, a gas diffusion port is provided between the first chamber and the second chamber, a gas diffusion membrane is fixedly installed in the gas diffusion port, a product discharge port is fixedly provided on the second chamber, a product discharge valve is fixedly installed at the product discharge port.

[0007] Furthermore, the sealed electrolytic cell comprises a first electrolytic cell and a second electrolytic cell, a connecting pipe is provided between the first electrolytic cell and the second electrolytic cell, and a cation exchange membrane is fixedly installed in the connecting pipe.

[0008] Furthermore, a water level sensor is fixedly installed in the sealed electrolytic cell, and a water level sensor is also fixedly installed in the product recovery device.

[0009] Furthermore, a water level automatic control system is fixedly installed in the outer shell, and the water level control system is electrically connected to a peristaltic pump, a gas pressurizing device and a water level sensor. The peristaltic pump is respectively arranged between the physical filtration bin and the closed electrolytic cell and between the closed electrolytic cell and the product recovery device. The output end of the gas pressurizing device is fixedly connected to the product recovery device.

[0010] Furthermore, the electrochemical workstation includes an electrochemical controller, and a reference electrode electrically connected to the electrochemical controller, a cathode sheet, a water level sensor, and an electrocatalyst releasing device.

[0011] Furthermore, a plurality of partition plates are fixedly installed in the physical filter bin, and filter fillers are respectively arranged between the plurality of partition plates.

[0012] Furthermore, the filter filler includes a combination of one or more of activated carbon, volcanic rock, zeolite, sponge, broken bricks and cotton.

[0013] Furthermore, a solar panel is fixedly mounted on the upper end surface of the outer shell, a solar battery is fixedly mounted inside the outer shell, and an external power port is also fixedly mounted on the outer shell.

[0014] Furthermore, the electrocatalyst releasing device is a working electrode of a nickel foam loaded cuprous oxide catalyst, and the cathode sheet is an iridium ruthenium-titanium counter electrode.

[0015] Furthermore, a method for using the electrocatalytic reduction device to recover ammonium sulfate comprises the steps of:

[0016] S1, nitrate wastewater is injected into the wastewater pool, and after initial precipitation in the wastewater pool, the nitrate wastewater is pumped into the physical filtration tank by a peristaltic pump, and after solid impurities are removed in the physical filtration tank, it enters the closed electrolytic cell for nitrate electroconversion for reduction;

[0017] S2, a closed electrolytic cell is responsible for treating the physically filtered nitrate wastewater. It is an H-shaped closed electrolytic cell, wherein the first electrolytic cell and the second electrolytic cell are separated by a cation exchange membrane. The reaction is controlled by a three-electrode system, which includes a working electrode of a nickel foam-loaded cuprous oxide catalyst, an iridium ruthenium-titanium counter electrode and an Ag / AgCl reference electrode. A saturated Na2SO4 solution is injected into the anode chamber. The residence time of the sewage in the reaction tank is controlled to be (4-5) hours;

[0018] S3, after the electrolysis is completed, the peristaltic pump pumps the wastewater in the cathode chamber into the product collection device. The first chamber of the product collection device is the reaction liquid after electrolysis, and the second chamber is sulfuric acid. The middle is separated by a gas diffusion membrane. The pressure device is inflated to the left to promote the product ammonia nitrogen to pass through the gas diffusion membrane; when the product ammonia nitrogen combines with sulfuric acid to generate ammonium sulfate and reaches a certain concentration, the product output valve is opened to discharge the product for collection and utilization.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The invention has a simple structure, is easy to use, and greatly improves the nitrate reduction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention.

[0022] Reference numerals

[0023] 1. Wastewater tank; 2. Outer shell; 3. Physical filtration chamber; 4. Sealed electrolytic cell; 5. Electrochemical workstation; 6. Product recovery device; 61. First chamber; 62. Second chamber; 63. Gas diffusion membrane; 64. Discharge valve; 41. First electrolytic cell; 42. Second electrolytic cell; 43. Cation exchange membrane; 10. Water level sensor; 7. Water level automatic control system; 71. Peristaltic pump; 72. Gas pressurizing device; 51. Electrochemical controller; 52. Reference electrode; 53. Cathode sheet; 54. Electrocatalyst release device; 8. Solar battery; 9. External power port. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0025] See also Figure 1As shown, a device for recovering ammonium sulfate by electrocatalytic reduction comprises a wastewater tank 1 and an outer shell 2, wherein a physical filter chamber 3 is fixedly installed in the outer shell 2, the water inlet of the physical filter chamber 3 is connected to the wastewater tank 1, the water outlet of the physical filter chamber 3 is fixedly connected to a closed electrolytic cell 4, the upper end of the closed electrolytic cell 4 is fixedly connected to an electrochemical workstation 5, the lower end surface of the closed electrolytic cell 4 is fixedly provided with a guide outlet, the guide outlet is fixedly connected to a product recovery device 6, the product recovery device 6 comprises a first chamber 61 and a second chamber 62, a gas diffusion port is provided between the first chamber 61 and the second chamber 62, a gas diffusion membrane 63 is fixedly installed in the gas diffusion port, a product discharge port is fixedly provided on the second chamber 62, and a product discharge valve 64 is fixedly installed at the product discharge port.

[0026] Furthermore, the sealed electrolytic cell includes a first electrolytic cell 41 and a second electrolytic cell 42 , a connecting pipe is provided between the first electrolytic cell 41 and the second electrolytic cell 42 , and a cation exchange membrane 43 is fixedly installed in the connecting pipe.

[0027] Furthermore, a water level sensor 10 is fixedly installed in the sealed electrolytic cell, and a water level sensor 10 is also fixedly installed in the product recovery device 6.

[0028] Furthermore, a water level automatic control system 7 is fixedly installed in the outer shell 2, and the water level control system is electrically connected to a peristaltic pump 71, a gas pressurizing device 72 and a water level sensor 10. The peristaltic pump 71 is respectively arranged between the physical filtration bin 3 and the closed electrolytic cell 4 and between the closed electrolytic cell 4 and the product recovery device 6. The output end of the gas pressurizing device 72 is fixedly connected to the product recovery device 6.

[0029] Furthermore, the electrochemical workstation 5 includes an electrochemical controller 51 , a reference electrode 52 electrically connected to the electrochemical controller 51 , a cathode sheet 53 , a water level sensor 10 , and an electrocatalyst releasing device 54 .

[0030] Furthermore, a plurality of partition plates are fixedly installed in the physical filter chamber 3, and filter fillers are respectively arranged between the plurality of partition plates.

[0031] Furthermore, the filter filler includes a combination of one or more of activated carbon, volcanic rock, zeolite, sponge, broken bricks and cotton.

[0032] Furthermore, a solar panel is fixedly mounted on the upper end surface of the outer shell 2 , a solar battery 8 is fixedly mounted inside the outer shell 2 , and an external power port 9 is also fixedly mounted on the outer shell 2 .

[0033] Furthermore, the electrocatalyst releasing device 54 is a working electrode of a nickel foam loaded cuprous oxide catalyst, and the cathode plate 53 is an iridium ruthenium-titanium counter electrode.

[0034] Furthermore, a method for using the electrocatalytic reduction device to recover ammonium sulfate comprises the steps of:

[0035] S1, nitrate wastewater is injected into the wastewater tank 1, and after initial precipitation in the wastewater tank 1, the nitrate wastewater is pumped into the physical filtration tank 3 by the peristaltic pump 71, and after solid impurities are removed in the physical filtration tank 3, the nitrate wastewater enters the closed electrolytic cell 4 for nitrate electroconversion for reduction;

[0036] S2, the closed electrolytic cell 4 is responsible for treating the nitrate wastewater after physical filtration, which is an H-shaped closed electrolytic cell 4, wherein the first electrolytic cell 41 and the second electrolytic cell 42 are separated by a cation exchange membrane 43, and the reaction is controlled by a three-electrode system, which includes a working electrode of a nickel foam loaded cuprous oxide catalyst, an iridium ruthenium-titanium counter electrode and an Ag / AgCl reference electrode 52, and a saturated Na2SO4 solution is injected into the anode chamber, and the residence time of the sewage in the reaction tank is controlled to be (4-5) hours;

[0037] S3, after the electrolysis is completed, the peristaltic pump 71 pumps the wastewater that has been electrolyzed in the cathode chamber into the product collection device. The first chamber 61 of the product collection device is the reaction liquid after electrolysis, and the second chamber 62 is sulfuric acid. The middle is separated by a gas diffusion membrane 63, and the pressurizing device is used to inflate to the left to promote the product ammonia nitrogen to pass through the gas diffusion membrane 63; when the product ammonia nitrogen combines with sulfuric acid to generate ammonium sulfate and reaches a certain concentration, the product output valve is opened to discharge the product for collection and utilization.

[0038] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed by the present invention should be included in the protection scope recorded in the claims.

Claims

1. A device for recovering ammonium sulfate by electrocatalytic reduction, comprising a wastewater tank (1) and an outer shell (2), characterized in that: A physical filter chamber (3) is fixedly installed in the outer shell (2); the water inlet of the physical filter chamber (3) is connected to the wastewater pool (1); the water outlet of the physical filter chamber (3) is fixedly connected to a closed electrolytic cell (4); the upper end of the closed electrolytic cell (4) is fixedly connected to an electrochemical workstation (5); a guide outlet is fixedly opened on the lower end surface of the closed electrolytic cell (4); the guide outlet is fixedly connected to a product recovery device (6); the product recovery device (6) comprises a first chamber (61) and a second chamber (62); a gas diffusion port is opened between the first chamber (61) and the second chamber (62); a gas diffusion membrane (63) is fixedly installed in the gas diffusion port; a product discharge port is fixedly opened on the second chamber (62); a product discharge valve (64) is fixedly installed at the product discharge port.

2. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 1, characterized in that: The sealed electrolytic cell comprises a first electrolytic cell (41) and a second electrolytic cell (42), a connecting pipeline is provided between the first electrolytic cell (41) and the second electrolytic cell (42), and a cation exchange membrane (43) is fixedly installed in the connecting pipeline.

3. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 1, characterized in that: A water level sensor (10) is also fixedly installed in the sealed electrolytic cell, and a water level sensor (10) is also fixedly installed in the product recovery device (6).

4. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 1, characterized in that: A water level automatic control system (7) is also fixedly installed in the outer shell (2). The water level control system is electrically connected to a peristaltic pump (71), a gas pressurizing device (72) and a water level sensor (10). The peristaltic pump (71) is respectively arranged between the physical filtration bin (3) and the closed electrolytic cell (4) and between the closed electrolytic cell (4) and the product recovery device (6). The output end of the gas pressurizing device (72) is fixedly connected to the product recovery device (6).

5. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 1, characterized in that: The electrochemical workstation (5) comprises an electrochemical controller (51), a reference electrode (52) electrically connected to the electrochemical controller (51), a cathode sheet (53), a water level sensor (10) and an electrocatalyst releasing device (54).

6. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 1, characterized in that: A plurality of partition plates are fixedly installed in the physical filtering chamber (3), and filtering fillers are respectively arranged between the plurality of partition plates.

7. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 6, characterized in that: The filter filler comprises a combination of one or more of activated carbon, volcanic rock, zeolite, sponge, broken bricks and cotton.

8. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 1, characterized in that: A solar panel is fixedly mounted on the upper end surface of the outer shell (2), a solar battery (8) is fixedly mounted inside the outer shell (2), and an external power port (9) is also fixedly mounted on the outer shell (2).

9. The device for recovering ammonium sulfate by electrocatalytic reduction according to claim 5, characterized in that: The electrocatalyst releasing device (54) is a working electrode of a nickel foam loaded cuprous oxide catalyst, and the cathode plate (53) is an iridium ruthenium-titanium counter electrode.

10. A method for using the electrocatalytic reduction and ammonium sulfate recovery device according to any one of claims 1 to 9, characterized in that: Includes steps: S1, nitrate wastewater is injected into a wastewater tank (1), and after initial precipitation in the wastewater tank (1), the nitrate wastewater is pumped into a physical filtration chamber (3) by a peristaltic pump (71), and after solid impurities are removed in the physical filtration chamber (3), the nitrate wastewater enters a closed electrolytic cell (4) for nitrate electroconversion for reduction; S2, a closed electrolytic cell (4) is responsible for treating the physically filtered nitrate wastewater, and is an H-shaped closed electrolytic cell (4), wherein the first electrolytic cell (41) and the second electrolytic cell (42) are separated by a cation exchange membrane (43), and the reaction is controlled by a three-electrode system, which includes a working electrode of a nickel foam loaded cuprous oxide catalyst, an iridium ruthenium-titanium counter electrode and an Ag / AgCl reference electrode (52), and a saturated Na2SO4 solution is injected into the anode chamber, and the residence time of the wastewater in the reaction tank is controlled to be (4-5) hours; S3, after the electrolysis is completed, the peristaltic pump (71) pumps the wastewater that has been electrolyzed in the cathode chamber into the product collection device. The first chamber (61) of the product collection device contains the reaction liquid after electrolysis, and the second chamber (62) contains sulfuric acid. The two chambers are separated by a gas diffusion membrane (63). The pressure device is used to inflate the gas to the left to promote the product ammonia nitrogen to pass through the gas diffusion membrane (63). When the product ammonia nitrogen combines with sulfuric acid to generate ammonium sulfate and reaches a certain concentration, the product output valve is opened to discharge the product for collection and utilization.

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