A device for recovering ammonia energy and hydrogen energy from high-ammonia-nitrogen organic wastewater

Abstract

The application relates to a device for recovering ammonia energy and hydrogen energy from high-ammonia-nitrogen organic wastewater, which utilizes a static electric field as driving force and utilizes a selective permeation membrane to separate NH4 + + from the wastewater, collects ammonia energy by using a chemical method, and is characterized in that the whole process is carried out at normal temperature and pressure, the requirement for equipment is low, H + + in a cathode chamber is converted into H2 by using a cathode reduction reaction, consumed electric energy is converted into hydrogen energy, part of the cost of recovering ammonia energy is offset, and the energy consumption of the ammonia energy recovery process is reduced. The cathode material used in the application is graphite, which has good conductivity and reduction capacity and can quickly convert H + + into H2 for recovery; the anode material used in the application is a DSA catalytic oxidation anode, which has good oxidation capacity and can efficiently oxidize and remove COD in the wastewater. The application has the technical effects of reducing the COD value of the wastewater and generating ammonia energy and hydrogen energy.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wastewater treatment, and specifically designs a device for recovering ammonia energy and hydrogen energy from high-ammonia-nitrogen organic wastewater. BACKGROUND

[0002] High-ammonia-nitrogen organic wastewater is often produced in coking industry, petrochemical industry, semiconductor industry, steel industry, food processing industry, etc. A large number of facts have proved that the discharge of high-ammonia-nitrogen organic wastewater is the main cause of water eutrophication. With the increasingly stringent discharge standards of high-ammonia-nitrogen wastewater in China, efficient removal of ammonia nitrogen (NH4 + ) in wastewater has become the primary task of the development of various industries. At present, the ammonia nitrogen in wastewater is mainly removed by nitrification / denitrification technology, which has high processing cost. Separating and recovering ammonia from high-concentration ammonia-nitrogen wastewater is an effective way, such as magnesium ammonium phosphate precipitation method, ammonia evaporation process, etc. In recent years, ammonia energy has gradually entered people's field of vision. Ammonia (NH3) is an effective energy and hydrogen carrier, and ammonia as a carbon-free compound, the combustion product is pure and carbon-free, which can be used as a clean energy for direct combustion. The importance of ammonia energy has been gradually promoted to the same position as hydrogen energy. Therefore, recovering ammonia energy from high-ammonia-nitrogen organic wastewater has become a new way for various industries to treat high-ammonia-nitrogen organic wastewater.

[0003] At present, some technicians in the field adopt a vacuum system with 0.1-0.5 atm to convert NH4 + in wastewater into ammonia gas, and then into liquid ammonia for recovery. During operation, the system needs to be kept at a temperature of 30-60℃. This vacuum system needs to be completed in a strictly sealed space, which has high requirements for equipment, and needs to consume a lot of energy in order to maintain the required conditions. Therefore, how to recover ammonia in wastewater mildly and with low energy consumption has become a key problem to be solved in the field of ammonia energy utilization. SUMMARY

[0004] (I) Technical problems to be solved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present application provides a device for recovering ammonia energy and hydrogen energy from high-ammonia-nitrogen organic wastewater, which adopts a method combining "electrostatic field + selective permeation membrane + chemical reaction" to recover ammonia energy from high-ammonia-nitrogen organic wastewater mildly, and at the same time converts the consumed electric energy into hydrogen energy to offset part of the energy consumption cost of ammonia energy recovery, which has the advantages of integrating sewage treatment, ammonia energy recovery and hydrogen energy production, being green and environmentally friendly, having mild operating conditions and low energy consumption.

[0006] (II) Technical solutions

[0007] The technical solutions of the present application are as follows:

[0008] The device for recovering ammonia energy and hydrogen energy from high-ammonia-nitrogen organic wastewater comprises an electrolytic cell (1), a first graphite cathode (6) and a second graphite cathode (6) arranged at two ends of the electrolytic cell respectively, a DSA catalytic oxidation anode (7) arranged at a middle position of the electrolytic cell (1), a first distance between the first graphite cathode (6) and the DSA catalytic oxidation anode (7), a monovalent cation selective permeation membrane or an ammonium ion selective permeation membrane (8) arranged in the first distance, a second distance between the second graphite cathode (6) and the DSA catalytic oxidation anode (7), and a monovalent cation selective permeation membrane or an ammonium ion selective permeation membrane (8) arranged in the second distance.

[0009] The DSA catalytic oxidation anode (7) and the monovalent cation selective permeation membrane or the ammonium ion selective permeation membrane (8) on both sides thereof form an anode chamber (10); the first graphite cathode (6) and the adjacent monovalent cation selective permeation membrane or ammonium ion selective permeation membrane (8) form a cathode chamber (9); and the second graphite cathode (6) and the adjacent monovalent cation selective permeation membrane or ammonium ion selective permeation membrane (8) form a cathode chamber (9).

[0010] The anode chamber (10) is provided with a water inlet (4) at a bottom thereof for inputting high-ammonia-nitrogen organic wastewater to be treated and a water outlet (5) at a top thereof for outputting organic wastewater treated by oxidation and degradation; the cathode chamber (9) is provided with an absorption liquid inlet (1) at a bottom thereof for inputting absorption liquid, and a gas outlet (2) and an absorption liquid pump (3) at a top thereof, the absorption liquid pump (3) being connected with a circulating absorption liquid tank (12), the circulating absorption liquid tank (12) being connected with the absorption liquid inlet (1) at the bottom of the cathode chamber (9); ammonium salt output from the circulating absorption liquid tank (12) is mixed with lye to react, and then enters an ammonia evaporation tower (15) to evaporate, and ammonia gas generated by evaporation is collected.

[0011] The first graphite cathode (6) and the second graphite cathode (6) are connected with a negative electrode of a chemical workstation (19), the DSA catalytic oxidation anode (7) is connected with a positive electrode of the chemical workstation (19), the absorption liquid is acid liquid, and the gas discharged from the gas outlet (2) contains hydrogen.

[0012] According to the preferred embodiment of the present application, a wastewater storage tank (11) is further included for storing high-ammonia-nitrogen organic wastewater to be treated, so as to homogenize the wastewater and stabilize the input speed of the wastewater into the electrolytic cell (1).

[0013] According to the preferred embodiment of the present application, the absorption liquid is stored in an acid liquid tank (13), the acid liquid in the acid liquid tank is dilute sulfuric acid, carbonic acid, sulfurous acid, nitric acid or nitrous acid; and the acid liquid tank (13) is connected with the circulating absorption liquid tank (12) or the absorption liquid inlet (1).

[0014] According to the preferred embodiment of the present application, the alkali solution tank (14) is used to store sodium hydroxide solution or calcium hydroxide solution, and the alkali solution tank (14) is connected to the ammonia absorption tower (15) to react with the ammonium salt solution from the circulating absorption tank (12) to produce ammonium hydroxide, which is evaporated in the ammonia absorption tower (15) to produce ammonia gas.

[0015] According to the preferred embodiment of the present application, the freezing compression tank (16) is used to collect the ammonia gas from the top of the ammonia absorption tower (15) and compress the ammonia gas into liquid ammonia (ammonia energy).

[0016] According to the preferred embodiment of the present application, the gas outlet (2) is connected to the hydrogen storage tank (18), and when the gas from the gas outlet (2) contains acidic gas such as CO2 or sulfur dioxide, a gas washing tank is arranged between the gas outlet (2) and the hydrogen storage tank (18), and the gas washing medium in the gas washing tank is sodium hydroxide, calcium hydroxide, dilute acid or water.

[0017] According to the preferred embodiment of the present application, when the gas washing medium in the gas washing tank is dilute acid or water, the gas washing tank is also connected to the acid solution tank (13) or the absorption liquid inlet (1).

[0018] According to the preferred embodiment of the present application, the circulating absorption tank (12) is provided with a pH sensor (17), and when the pH sensor (17) detects that the pH in the circulating absorption tank (12) is greater than or equal to 8.5, the operation of the absorption pump (3) is stopped, the ammonium salt solution in the circulating absorption tank (12) is discharged and reacts with the alkali solution, and then enters the ammonia absorption tower (15) to evaporate ammonia gas.

[0019] According to the preferred embodiment of the present application, the acid solution tank (13) is connected to the acid production tower (131), and the acid production tower (131) is connected to wastewater and acidic waste gas from a power plant, and the acidic waste gas includes at least one of sulfur dioxide, nitrogen oxide, sulfur trioxide and carbon dioxide.

[0020] According to the preferred embodiment of the present application, an insulating mesh cylinder is arranged around the DSA catalytic oxidation anode (7), the insulating mesh cylinder is sleeved on the outside of the DSA catalytic oxidation anode (7) and takes the DSA catalytic oxidation anode (7) as the center, and the insulating mesh cylinder occupies the anode chamber (10); the insulating mesh cylinder is filled with stainless steel ball particles with a diameter of 1-10 mm and a precious metal coating.

[0021] According to the preferred embodiment of the present application, the DSA catalytic oxidation anode (7) is installed with multiple layers of horizontal stainless steel meshes along the height direction of the DSA catalytic oxidation anode (7), and the horizontal stainless steel meshes have a precious metal coating on the surface; the horizontal stainless steel meshes have a mesh size of 0.5-5 mm; the horizontal stainless steel meshes have a transverse length occupying the anode chamber (10); and molecular sieve or nutshell activated carbon is filled between two adjacent layers of horizontal stainless steel meshes.

[0022] In this article, the DSA catalytic oxidation anode is a titanium anode, officially called a titanium-based mixed noble metal oxide coated titanium anode (MMO), also known as a DSA anode (shape-stable anode). It uses titanium as the substrate and coats it with a noble metal coating, giving it good electrocatalytic activity and conductivity.

[0023] (III) Beneficial Effects

[0024] This invention utilizes an electrostatic field as the driving force to selectively separate NH4 from wastewater using a membrane. + Ammonia can then be collected chemically. The entire process is carried out at room temperature and pressure, requiring relatively low equipment specifications. Simultaneously, it utilizes a cathode reduction reaction to remove H₂ from the cathode chamber. + The energy consumed is converted into hydrogen energy, specifically H2, thus offsetting part of the cost of ammonia recovery and reducing energy consumption in the ammonia recovery process. The cathode material used in this invention is graphite, which has excellent conductivity and reduction capabilities, enabling rapid conversion of H2 into hydrogen energy. + The anode material used in this invention is a DSA catalytic oxidation anode, which has good oxidation ability and can efficiently and thoroughly oxidize and remove COD from wastewater. It has the technical effects of reducing the COD value of wastewater and generating ammonia and hydrogen energy.

[0025] In some embodiments of the present invention, the ability to degrade COD in wastewater is improved by modifying the structure of the DSA catalytic oxidation anode.

[0026] In some embodiments of the present invention, the absorbent is obtained by reacting acidic waste gas from a power plant with water, which can reduce acidic gas pollution and carbon emissions, and generate high-value-added hydrogen and ammonia energy, thus having both environmental and economic benefits.

[0027] In some embodiments of the present invention, the alkaline solution used is calcium hydroxide, which reacts with ammonium salts in the circulating suction tank to generate byproducts such as calcium carbonate or calcium sulfate gypsum, thereby improving the economic efficiency of the process. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of a preferred embodiment 1 of the present invention.

[0029] Figure 2 This is a schematic diagram of a preferred embodiment 2 of the present invention.

[0030] Figure 3 This is a schematic diagram of the structure of the DSA catalytic oxidation anode 7 in the preferred embodiment 3 of the present invention.

[0031] Figure 4 This is a schematic diagram of the structure of the DSA catalytic oxidation anode 7 in the preferred embodiment of the present invention. Detailed Implementation

[0032] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Example 1

[0034] like Figure 1 As shown, this is an apparatus for recovering ammonia and hydrogen energy from high-ammonia nitrogen organic wastewater according to Embodiment 1 of the present invention. It includes an electrolytic cell 1, with a first graphite cathode 6 and a second graphite cathode 6 (which are plate-shaped electrodes) respectively provided at both ends of the electrolytic cell. A DSA catalytic oxidation anode 7 (which is a plate-shaped or rod-shaped electrode) is provided in the middle of the electrolytic cell 1. The distances from the DSA catalytic oxidation anode 7 to the first graphite cathode 6 and the second graphite cathode 6 are equal.

[0035] The first graphite cathode 6 is separated from the DSA catalytic oxidation anode 7 by a first distance, within which a monovalent cation selective permeable membrane or an ammonium ion selective permeable membrane 8 is provided. The second graphite cathode 6 is separated from the DSA catalytic oxidation anode 7 by a second distance, within which a monovalent cation selective permeable membrane or an ammonium ion selective permeable membrane 8 is provided. The first graphite cathode 6 and the second graphite cathode 6 are connected to the negative electrode of the chemical workstation 19, and the DSA catalytic oxidation anode 7 is connected to the positive electrode of the chemical workstation 19. The DSA catalytic oxidation anode 7 and the monovalent cation selective permeable membranes or ammonium ion selective permeable membranes 8 on both sides form an anode chamber 10. The first graphite cathode 6 and the adjacent monovalent cation selective permeable membrane or ammonium ion selective permeable membrane 8, and the second graphite cathode 6 and the adjacent monovalent cation selective permeable membrane or ammonium ion selective permeable membrane 8 respectively form cathode chambers 9.

[0036] The anode chamber 10 is provided with a water inlet 4 at the bottom for inputting high ammonia-nitrogen organic wastewater to be treated, and a water outlet 5 at the top for outputting the organic wastewater treated by oxidation and degradation. The cathode chamber 9 is provided with an absorption liquid inlet 1 at the bottom for inputting absorption liquid, and a gas outlet 2 and an absorption liquid pump 3 at the top. The absorption liquid pump 3 is connected to a circulating absorption liquid tank 12. The gas outlet 2 discharges hydrogen gas, and is connected to a hydrogen storage tank 18. The circulating absorption liquid tank 12 is also connected to the absorption liquid inlet 1 at the bottom of the cathode chamber 9, and the ammonium salt in the circulating absorption liquid tank 12 and the acid liquid from an acid liquid tank 13 are input into the cathode chamber 9 through circulation to accumulate the ammonium salt to a higher concentration. A pH sensor 17 is arranged on the circulating absorption liquid tank 12, and when the pH sensor 17 monitors that the pH in the circulating absorption liquid tank 12 is greater than or equal to 8.5, the operation of the absorption liquid pump 3 is stopped, the ammonium salt solution in the circulating absorption liquid tank 12 is discharged and mixed with the alkali liquid output from an alkali liquid tank 14 to react, and then enters an ammonia evaporation tower 15 for evaporation. The ammonia gas generated by evaporation is collected. The ammonia gas is input into a refrigeration compression tank 16 for low-temperature compression to form liquid ammonia (ammonia energy). In the embodiment, the absorption liquid input into the absorption liquid inlet 1 is acid liquid, the absorption liquid is stored in the acid liquid tank 13, the acid liquid in the acid liquid tank 13 is dilute sulfuric acid, and the alkali liquid in the alkali liquid tank 14 is sodium hydroxide solution. The acid liquid tank 13 is connected to the circulating absorption liquid tank 12 or the absorption liquid inlet 1.

[0037] The working principle of the embodiment is as follows:

[0038] The high ammonia-nitrogen organic wastewater is stored in a wastewater storage tank 11, which is used to homogenize the wastewater and stabilize the input speed into the electrolytic tank 1. After the high ammonia-nitrogen organic wastewater is input into the anode chamber 10, the organic pollutants in the wastewater are directly oxidized and degraded on the surface of the DSA catalytic oxidation anode 7, so that the COD in the wastewater is reduced, and then discharged from the water outlet 5 at the top of the anode chamber 10. The acid liquid (dilute sulfuric acid) in the circulating absorption liquid tank 12 is input into the cathode chamber 9 under the action of a pump from the absorption liquid inlet 1. Under the action of the electric field, the cations and NH4 + Under the action of the electric field, the monovalent cations or the ammonium ions pass through the monovalent cation selective permeation membrane or the ammonium ion selective permeation membrane 8 into the cathode chamber 9, and the NH4 + react with SO4 2- to generate (NH4)2SO4, which is discharged from the absorption liquid pump 3 together with the absorption liquid dilute sulfuric acid and returned to the circulating absorption liquid tank 12. Since the ammonium salt and the dilute sulfuric acid solution in the circulating absorption liquid tank 12 are continuously circulated between the cathode chamber 9 and the circulating absorption liquid tank 12, the concentration of the ammonium salt in the circulating absorption liquid tank 12 becomes higher and higher. The H + On the surface of the graphite cathode 6, the H

[0039] As the process of treating organic waste water continues, the concentration of (NH4)2SO4 in the circulating absorption tank 12 increases, and the pH in the circulating absorption tank 12 increases as well. When the pH in the circulating absorption tank 12 reaches 8.5, the system is stopped, and the solution in the circulating absorption tank 12 is drained out. The solution is mixed with the NaOH solution from the alkali tank 14 to form Na2SO4 and NH4OH, which are fed into the ammonia distillation tower 15. In the ammonia distillation tower 15, Na2SO4 is discharged from the bottom of the ammonia distillation tower 15 and collected, and NH3 is discharged from the top of the ammonia distillation tower 15 and fed into the refrigeration compression tank 16 to form liquid ammonia, which is stored as ammonia energy. After the solution in the circulating absorption tank 12 is drained out, the acid tank 13 quickly injects new dilute H2SO4 solution into the circulating absorption tank 12, and the system is started again.

[0040] In the above embodiment, the alkali solution stored in the alkali tank 14 is NaOH solution. In other embodiments, the alkali solution stored in the alkali tank 14 is calcium hydroxide solution, or the alkali tank 14 is removed, and calcium oxide powder is directly sprayed into the ammonia distillation tower 15, and calcium sulfate solid (i.e. gypsum) is discharged from the bottom of the ammonia distillation tower 15.

[0041] In the above embodiment, the acid solution stored in the acid tank 13 is dilute sulfuric acid solution. In other embodiments, the dilute sulfuric acid solution can be replaced by dilute nitric acid solution, dilute hydrochloric acid solution, sulfurous acid, nitric acid or nitrous acid. When the acid solution is nitric acid solution, the circulating absorption tank 12 can produce ammonium nitrate (a nitrogen-rich fertilizer), which can be concentrated or concentrated combined with refrigeration crystallization to obtain ammonium nitrate crystals.

[0042] In the above embodiment, the acid solution stored in the acid tank 13 is dilute sulfuric acid solution. In other embodiments, the dilute sulfuric acid solution can be replaced by carbonic acid solution. When the absorption solution input into the cathode chamber is carbonic acid solution, the gas discharged from the gas outlet 2 can include CO2 and hydrogen gas, and a gas washing tank 181 is provided between the gas outlet 2 and the hydrogen storage tank 18. The gas washing medium in the gas washing tank 181 is sodium hydroxide, calcium hydroxide, dilute acid or water. The circulating absorption tank 12 outputs ammonium carbonate, which reacts with sodium hydroxide output from the alkali tank 14 to produce ammonia gas and baking soda, or reacts with calcium hydroxide output from the alkali tank 14 to produce ammonia gas and calcium carbonate solid. When the gas washing medium in the gas washing tank is dilute acid or water, the gas washing tank is also connected to the acid tank 13 or the absorption solution inlet 1 to provide part of the acid solution as absorption solution, and to produce hydrogen gas on the surface of the graphite cathode 6.

[0043] Embodiment 2

[0044] As Figure 2As shown, the difference between this embodiment and Embodiment 1 is that the acid in the acid tank 13 is the acid produced by the acid-producing tower 131, which is connected to wastewater and acidic waste gas from the power plant. The acidic waste gas includes at least one of sulfur dioxide, nitrogen oxides, sulfur trioxide, and carbon dioxide. The absorbent stored in the acid tank 13 is at least one or a combination of two or more of the following: carbonic acid, sulfuric acid, sulfurous acid, nitric acid, or nitrous acid. Since acids such as carbonic acid, sulfurous acid, and nitrous acid are unstable and easily decompose, a gas scrubbing tank 181 needs to be installed between the gas outlet 2 and the hydrogen storage tank 18. The scrubbing medium in the gas scrubbing tank can be sodium hydroxide, calcium hydroxide, dilute acid, or water to absorb CO2 or sulfur dioxide gas. When the scrubbing medium in the gas scrubbing tank 181 is dilute acid or water, the gas scrubbing tank 181 can be connected to the acid tank 13 or the absorbent inlet 1 to provide absorbent to the cathode chamber 9 and generate hydrogen on the surface of the graphite cathode 6. This embodiment can convert acidic pollutant gases emitted by power plants into acidic liquid. Using the acidic liquid as an absorbent, hydrogen is obtained in the cathode chamber 9. At the same time, the anionic portion of the acidic liquid reacts with ammonium ions to produce nitrogen fertilizer. The ammonium salt can further react with alkaline solution to generate sodium salt or calcium salt, etc., thus realizing the fixation of acidic gases and generating high-value-added clean hydrogen energy.

[0045] Example 3

[0046] like Figure 3 As shown, this embodiment differs from Embodiments 1 or 2 in that the DSA catalytic oxidation anode 7 is modified to improve COD degradation efficiency. The DSA catalytic oxidation anode 7 is a rod-shaped electrode, with a large insulating mesh cylinder 71 arranged around it as the center. The insulating mesh cylinder 71 occupies the anode chamber 10, and stainless steel spheres 72 with a diameter of 1-10 mm are filled inside the insulating mesh cylinder 71. The stainless steel spheres 72 are conductive and have a noble metal coating on their surface, thereby greatly increasing the actual electrode catalytic area of ​​the DSA catalytic oxidation anode 7 and improving its ability to degrade COD in high ammonia nitrogen organic wastewater.

[0047] Example 4

[0048] like Figure 4As shown, the difference between the present embodiment and Embodiments 1 or 2 is that the DSA catalytic oxidation anode 7 is modified to improve the COD degradation efficiency. The DSA catalytic oxidation anode 7 is a rod-shaped electrode, and a plurality of horizontal stainless steel meshes 73 are installed along the height direction of the DSA catalytic oxidation anode 7, the horizontal stainless steel meshes 73 have a noble metal coating on the surface and take the DSA catalytic oxidation anode 7 as the central axis; the mesh size of the horizontal stainless steel meshes is 0.5-5 mm, and the horizontal length of the horizontal stainless steel meshes 73 occupies the anode chamber 10. Molecular sieve or shell (preferably coconut shell) activated carbon 74 is filled between two adjacent horizontal stainless steel meshes, through these large-particle adsorbents, the adsorption and fixation of small-molecule organic matter in water and the time-delay residence of large-molecule organic matter can be strengthened, so as to strengthen the removal capacity of the DSA catalytic oxidation anode 7 to the COD in water. According to the test, the technical effect of the present embodiment is better than that of Embodiment 3.

[0049] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A device for recovering ammonia and hydrogen energy from high-ammonia-nitrogen organic wastewater, characterized in that, It includes an electrolytic cell (1), with a first graphite cathode (6) and a second graphite cathode (6) respectively at both ends of the electrolytic cell. A DSA catalytic oxidation anode (7) is provided in the middle of the electrolytic cell (1). The first graphite cathode (6) and the DSA catalytic oxidation anode (7) are separated by a first distance. A monovalent cation selective permeable membrane or an ammonium ion selective permeable membrane (8) is provided within the first distance. The second graphite cathode (6) and the DSA catalytic oxidation anode (7) are separated by a second distance. A monovalent cation selective permeable membrane or an ammonium ion selective permeable membrane (8) is provided within the second distance. The DSA catalytic oxidation anode (7) forms an anode chamber (10) between the monovalent cation selective permeable membrane or ammonium ion selective permeable membrane (8) on both sides; and a cathode chamber (9) is formed between the first graphite cathode (6) and the adjacent monovalent cation selective permeable membrane or ammonium ion selective permeable membrane (8), and between the second graphite cathode (6) and the adjacent monovalent cation selective permeable membrane or ammonium ion selective permeable membrane (8). The anode chamber (10) is provided with an inlet (4) at the bottom for inputting high ammonia nitrogen organic wastewater to be treated, and an outlet (5) at the top for outputting organic wastewater treated by oxidation degradation; the cathode chamber (9) is provided with an absorbent inlet at the bottom for inputting absorbent, and a gas outlet (2) and a suction pump (3) at the top of the cathode chamber (9). The suction pump (3) is connected to the circulating suction tank (12), and the circulating suction tank (12) is connected to the absorbent inlet at the bottom of the cathode chamber (9); the circulating suction tank (12) is provided with a pH sensor (17). When the pH sensor (17) detects that the pH in the circulating suction tank (12) is ≥8.5, the suction pump (3) stops working, and the ammonium salt solution in the circulating suction tank (12) is exported and reacted with the alkaline solution before entering the ammonia stripping tower (15) for evaporation. The ammonia gas generated by evaporation is collected. The first graphite cathode (6) and the second graphite cathode (6) are connected to the negative electrode of the chemical workstation (19), and the DSA catalytic oxidation anode (7) is connected to the positive electrode of the chemical workstation (19). The absorbent is an acid solution, and the gas discharged from the gas outlet (2) contains hydrogen. The absorbent is stored in an acid tank (13), and the acid in the acid tank is dilute sulfuric acid, carbonic acid, sulfurous acid, nitric acid, or nitrous acid. The acid tank (13) is connected to a circulating suction tank (12). The acid tank (13) is connected to an acid production tower (131), which is connected to wastewater and acidic waste gas from the power plant. The acidic waste gas includes at least one of sulfur dioxide, nitrogen oxides, sulfur trioxide, and carbon dioxide. After all the absorbent in the circulating suction tank (12) is discharged, the acid tank (13) quickly injects a new quantitative amount of dilute H2SO4 solution into the circulating suction tank (12), and then the system is restarted.

2. The apparatus according to claim 1, characterized in that, It also includes a wastewater storage tank (11) for storing high ammonia nitrogen organic wastewater to be treated, so as to homogenize the wastewater and stabilize the rate at which it is fed into the electrolyzer (1).

3. The apparatus according to claim 1, characterized in that, It also includes an alkali tank (14) which stores alkali solution, which is sodium hydroxide solution or calcium hydroxide solution; the alkali solution output from the alkali tank (14) reacts with the ammonium salt solution output from the circulating liquid absorption tank (12) to generate ammonium hydroxide, and the ammonium hydroxide enters the ammonia stripping tower (15) to evaporate and generate ammonia gas, which is discharged from the top of the ammonia stripping tower (15).

4. The apparatus according to claim 1, characterized in that, It also includes a refrigerated compression tank (16) for collecting ammonia gas discharged from the top of the ammonia stripping tower (15) and compressing the ammonia gas into liquid ammonia.

5. The apparatus according to claim 1, characterized in that, The gas outlet (2) is connected to the hydrogen storage tank (18); when the gas discharged from the gas outlet (2) contains acidic gas, a gas washing tank is provided between the gas outlet (2) and the hydrogen storage tank (18), and the gas washing medium in the gas washing tank is sodium hydroxide, calcium hydroxide, dilute acid or water.

6. The apparatus according to claim 5, characterized in that, When the washing medium in the washing tank is dilute acid or water, the washing tank is also connected to the acid tank (13).

7. The apparatus according to claim 1, characterized in that, An insulating mesh cylinder is provided around the DSA catalytic oxidation anode (7), the insulating mesh cylinder is fitted over the outside of the DSA catalytic oxidation anode (7) and centered on the DSA catalytic oxidation anode (7), the insulating mesh cylinder occupies the anode chamber (10); the insulating mesh cylinder is filled with stainless steel granules with a diameter of 1-10 mm and coated with precious metals; or, The DSA catalytic oxidation anode (7) is equipped with multiple layers of horizontal stainless steel mesh along its height direction. The surface of the horizontal stainless steel mesh has a noble metal coating. The mesh size of the horizontal stainless steel mesh is 0.5-5 mm. The transverse length of the horizontal stainless steel mesh occupies the anode chamber (10). Molecular sieves or fruit shell activated carbon are filled between two adjacent layers of horizontal stainless steel mesh.

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