Device for treating high-concentration ammonium salt wastewater by adopting membrane technology

Abstract

The invention discloses a device for treating high-concentration ammonium salt wastewater by adopting a membrane technology, which belongs to the field of sewage treatment, is used for treating the high-concentration ammonium salt wastewater, and comprises the following steps: adjusting the alkali of the wastewater injected into a mother liquor tank, heating the alkali-adjusted wastewater in a mother liquor preheater, and heating the mother liquor preheater; the heated wastewater is fed into a liquid inlet of the columnar membrane reactor and forms turbulent flow through a liquid distribution pipe and a flow guide baffle in the columnar membrane reactor; a sulfuric acid solution in the acid storage tank is fed into an acid inlet of the columnar membrane reactor through a pump body, and the sulfuric acid solution and wastewater are located on the two sides of the hollow fiber membrane respectively and form a concentration gradient; and the sulfuric acid solution after generating ammonium sulfate crystals circularly enters the acid storage tank. According to the application, ammonia nitrogen selective adsorption in the presence of antibiotics can be successfully realized, ammonia nitrogen can be converted into high-added-value products, and cyclic utilization and appreciation of resources are realized.

Description

Technical Field

[0001] The present invention relates to the field of sewage treatment, and more specifically, to a device for treating high-concentration ammonium salt wastewater using membrane technology. Background Art

[0002] Currently, the main methods for treating high ammonium salt wastewater containing antibiotics are air stripping, evaporation crystallization, membrane separation technology, and steam distillation.

[0003] Air stripping is a physicochemical treatment technology based on the principle of gas-liquid mass transfer. By regulating the chemical equilibrium and physical conditions in the wastewater, dissolved volatile pollutants (such as ammonia nitrogen) are transferred from the liquid phase to the gas phase, thereby achieving the separation and removal of pollutants. Although air stripping offers the advantages of rapid load reduction and mature technology in the treatment of high-ammonium salt wastewater, it requires technical upgrades through anti-scaling design, energy recovery, and intelligent control.

[0004] Evaporative crystallization involves heating and evaporating the solvent from a solution, gradually increasing the solute concentration until saturation is achieved and crystals are precipitated. The core of evaporative crystallization is to vaporize the solvent (usually water) in the solution by heating, thereby continuously increasing the solute concentration. Once the solution reaches saturation, further evaporation of the solvent causes the solute to precipitate as crystals. However, this method is primarily suitable for substances whose solubility does not change much with temperature.

[0005] Steam stripping distillation is a technology that uses steam or other gases as a carrier gas to transfer volatile substances (such as ammonia and hydrogen sulfide) dissolved in wastewater from the liquid phase to the vapor phase through gas-liquid contact, thereby achieving separation and purification. The core of steam stripping distillation is based on gas-liquid equilibrium and mass transfer processes. By introducing steam or other gases into the wastewater, the partial pressure of the target components in the vapor phase is reduced, thereby promoting the escape of these volatile substances from the liquid phase into the vapor phase.

[0006] However, in the existing technology, biological treatment is still the main method. However, the wastewater produced by the pharmaceutical industry in the production of antibiotics often exceeds the tolerance limit of conventional biological treatment systems. Taking cephalosporin wastewater as an example, the residual cephalosporin content is about 20 mg / L, the COD content is about 20,000 mg / L, the total dissolved solids content is about 15,000~28,000 mg / L, and the conductivity is about 18~32 m 2 / cm, which is 3 to 5 times the tolerance limit of conventional biological treatment systems. The high salt environment in wastewater easily leads to a triple treatment dilemma: 1. The inhibitory effect of the biological treatment system, the activity of the digestive flora is inhibited, and the denitrification process is disturbed, affecting the efficiency of the subsequent biochemical treatment.

[0007] 2. It will cause the physical and chemical process to fail. Concrete failure will reduce the flocculation efficiency by 60%~70%, and salt crystallization will easily cause membrane pollution.

[0008] 3. The resource utilization of the product is hindered, the purity of ammonium salt is reduced, and the commercial value as a fertilizer raw material is lost.

[0009] Therefore, the high salinity and high ammonia nitrogen concentration in high ammonium salt wastewater place higher requirements on the tolerance of the biological treatment system. At the same time, it is also necessary to upgrade the single treatment technology in the biological treatment system to meet strict emission standards and resource recovery needs. Summary of the Invention

[0010] The purpose of this application is to provide a device for treating high-concentration ammonium salt wastewater using membrane technology, which can control the ammonium salt concentration in the wastewater, which is beneficial to the subsequent biochemical treatment; at the same time, it also solves the problem of high-concentration ammonium salt in high-concentration ammonium salt wastewater inhibiting the biological treatment system, and can successfully achieve selective adsorption of ammonia nitrogen in the presence of antibiotics. At the same time, through green conversion technology, ammonia nitrogen is converted into high-value-added products, thereby realizing the circular utilization and value-added of resources.

[0011] To achieve the above objectives, this application is implemented through the following technical solutions: The present application discloses a device for treating high-concentration ammonium salt wastewater by using membrane technology, which comprises the following steps: injecting high-concentration ammonium salt wastewater into a mother liquor pool, and adding alkaline solution in an alkali solution dosing tank into the mother liquor pool to adjust the pH of the high-concentration ammonium salt wastewater in the mother liquor pool to above 11; passing the high-concentration ammonium salt wastewater after alkali adjustment into a mother liquor preheater and raising the temperature to 60°C in the mother liquor preheater, and sending the high-concentration ammonium salt wastewater after the temperature is raised to 60°C into a membrane filter, and pre-filtering the high-concentration ammonium salt wastewater through the membrane filter; the high-concentration ammonium salt wastewater after prefiltration is sent to the liquid inlet at the bottom of the columnar membrane reactor through a booster pump and a PVC pipeline, and the high-concentration ammonium salt wastewater passes through the coordinated action of the internal water distribution pipe and the guide baffle. It is used to form uniform turbulence inside the columnar membrane reactor; the sulfuric acid solution in the acid storage tank is reversely pumped into the acid inlet of the columnar membrane reactor near the liquid inlet, and is physically isolated from the high-concentration ammonium salt wastewater after pre-filtration through the hydrophobic hollow fiber membrane in the columnar membrane reactor, and a concentration gradient is formed on both sides of the hollow fiber membrane. Driven by the concentration gradient, NH3 in the high-concentration ammonium salt wastewater selectively penetrates the membrane pores and enters the sulfuric acid solution side to form ammonium sulfate crystals. After the formation of ammonium sulfate crystals, the sulfuric acid solution is returned to the acid storage tank through the acid outlet and the circulation pipeline under the action of the pump body for recycling; the low-concentration ammonium salt wastewater formed after treatment enters the deammonification tank from the liquid outlet at the top of the columnar membrane reactor for coupling treatment with the subsequent biochemical system.

[0012] As one of the preferred technical solutions of the present application, the filtration accuracy of the membrane filter is 0.5μm, the material of the hydrophobic hollow fiber membrane in the columnar membrane reactor is polyvinylidene fluoride, the inner diameter of the membrane pore of the hollow fiber membrane is 0.01μm~0.1μm, and the porosity is 60~85%; the hollow fiber membrane is woven with membrane wire through a mesh weaving process, and then the membrane wire woven by the mesh process is rolled on the surface of the water distribution pipe, and a number of water distribution holes are distributed on the water distribution pipe.

[0013] As one of the preferred technical solutions of the present application, the alkaline solution in the alkali solution dosing tank is a sodium hydroxide solution, and the sodium hydroxide solution is adjusted by mechanical stirring after being added into the mother liquor pool.

[0014] As one of the preferred technical solutions of the present application, the mass concentration of the sodium hydroxide solution is 30%~32%.

[0015] As one of the preferred technical solutions of the present application, the ammonia nitrogen concentration of the high-concentration ammonium salt wastewater is 1500 mg / L~2000 mg / L.

[0016] As one of the preferred technical solutions of the present application, the ammonia nitrogen concentration of the high-concentration ammonium salt wastewater is 1800 mg / L~2000 mg / L.

[0017] As one of the preferred technical solutions of the present application, the pH value of the sulfuric acid solution is 0.1~0.5.

[0018] As one of the preferred technical solutions of the present application, the pH value of the sulfuric acid solution is 0.5.

[0019] As one of the preferred technical solutions of the present application, the acid storage tank and the mother liquor pool are both provided with pH monitors to monitor the pH values ​​of the acid storage tank and the mother liquor pool; the saturated sulfuric acid solution in the acid storage tank is recovered by an MVR evaporation device to realize ammonium salt recovery.

[0020] Compared with the prior art, the present invention has the following advantages: 1. This application can reduce the ammonium salt concentration in high-concentration ammonium salt cephalosporin wastewater by 80%, reduce the difficulty of subsequent biochemical treatment, and realize the recovery of ammonium salt in cephalosporin antibiotic wastewater.

[0021] 2. This application improves the membrane contact process, upgrades the traditional vertical membrane column to a three-dimensional gradient weaving structure, uses in-situ cross-linking technology of polymer materials to form a network system, and constructs a separation membrane component with a mechanical interlocking reinforcement layer (tensile strength increased by 230%). The specific surface area is doubled through precise weaving of membrane filaments, showing breakthrough performance in the treatment of cephalosporin antibiotic wastewater; under the action of turbulence, it can enhance mass transfer and increase the membrane-liquid contact efficiency by 40%. Combined with the low pressure drop characteristics brought by the gradient densification arrangement, this application has a small footprint and can be modularized to facilitate large-scale industrial application to treat large-flow, high-concentration ammonium salt wastewater, and the absorbed ammonia nitrogen can be recycled as ammonium salt.

[0022] 3. The columnar membrane reactor described in this application is provided with a water distribution pipe at the center, and a baffle is provided at the middle position of the columnar membrane reactor. The above structure can ensure that the water flows evenly through the entire membrane area and fully contacts with the sulfuric acid solution, thereby effectively improving the gas transmission efficiency between the shell side and the tube side.

[0023] 4. This application is different from other traditional denitrification technologies. It uses a mother liquor preheater to increase the temperature to achieve the best absorption efficiency of ammonium salts. It is simple to operate and can connect multiple membranes in series, reducing production costs and investment costs. It also significantly reduces environmental risks and improves economic benefits, providing strong support for the sustainable development of wastewater treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a flow chart of a device for controlling and recovering the ammonium salt concentration in the antibiotic cephalosporin wastewater containing high ammonium salt concentration in the present application.

[0025] Figure 2 This is a schematic diagram of a cylindrical membrane reactor in this application. Figure 1 .

[0026] Figure 3 It is a schematic diagram of the internal structure of the columnar membrane reactor in this application.

[0027] Figure 4 This is a graph showing changes in ammonia nitrogen concentration when the antibiotic cephalosporin wastewater with a high ammonium salt concentration is continuously treated for 4 hours in Example 1 of the present application.

[0028] In the figure: 1. Liquid inlet; 2. Acid inlet; 3. Acid outlet; 4. Liquid outlet; 5. Hollow fiber membrane; 6. Guide baffle; 7. Water distribution pipe; 8. Membrane column sealing ring; 9. Alkali solution dosing tank; 10. pH monitor; 11. Mother liquor tank; 12. Deammonification tank; 13. Mother liquor preheater; 14. Membrane filter; 15. Columnar membrane reactor; 16. Acid storage tank; 17. MVR evaporation device. DETAILED DESCRIPTION

[0029] The technical solution described in this application is further described below with reference to the accompanying drawings and embodiments.

[0030] See also Figures 1 to 3 The device used in this application includes a mother liquor pool 11, a deammonification pool 12, a mother liquor preheater 13, a membrane filter 14, a columnar membrane reactor 15, an acid storage tank 16, and an MVR device 17, wherein the mother liquor pool 11 is also connected to an alkali dosing tank 9. The mother liquor pool 11 is used to store and adjust the alkali of high-concentration ammonium salt pharmaceutical wastewater. The alkali adjustment is connected to the alkali dosing tank 9 through a pipeline. The alkali dosing tank 9 adds the sodium hydroxide solution stored inside the mother liquor pool 11 and mixes it with the wastewater in the mother liquor pool under mechanical stirring. The mother liquor pool 11 is also connected to the mother liquor preheater 13, and the mother liquor preheater 13 is connected to the membrane filter 14. The membrane filter 14 is connected to the liquid inlet 1 through a PVC pipeline and a booster pump, and the liquid outlet 4 is connected to the deammonification pool 12 through a pipeline. The acid outlet 3 and the acid inlet 2 on the columnar membrane reactor 15 are connected to the acid storage tank 16 to form a circulation pipeline, and a pump body is provided on the circulation pipeline. The acid storage tank 16 and the alkali solution dosing tank 9 are respectively provided with corresponding pH monitors, and the acid storage tank 16 is also connected to the MVR evaporation device 17. In the present application, the liquid outlet 4 can also send part of the low-concentration ammonium salt wastewater into the mother liquor tank 11 through a pipeline.

[0031] In the present application, the columnar membrane reactor 15 includes a main body of a hollow cylindrical structure, with a liquid inlet 1 and a liquid outlet 4 respectively connected at the bottom and top ends of the main body, an acid inlet 2 connected on the side wall near the liquid inlet 1, and an acid outlet 3 connected on the side wall near the liquid outlet 4. A water distribution pipe 7 is arranged at the central axis position of the main body of the hollow cylindrical structure, and a hollow fiber membrane 5 is wrapped on the circumferential outer wall of the water distribution pipe 7. The middle position of the water distribution pipe 7 is connected to the main body through a guide baffle 6, and column membrane sealing rings 8 for achieving sealed connection are provided at the connection positions of the liquid inlet 1, the acid inlet 2, the acid outlet 3, the liquid outlet 4 and the external pipe body.

[0032] This application utilizes membrane separation technology to implement an ammonium salt regulation system through a columnar membrane reactor 15, overcoming the limitations of traditional biological denitrification. This application utilizes a two-phase interface mass transfer channel within the hollow fiber membrane 5, made of polyvinylidene fluoride (PVDF), an internal component of the columnar membrane reactor 15. Under operating conditions of pH 11 and 60°C, ammonia nitrogen (NH3-N) from the wastewater side is activated by hot alkaline and converted into free NH3. Driven by a transmembrane partial pressure gradient, NH3 molecules selectively penetrate the membrane pores of the hollow fiber membrane 5 into the sulfuric acid absorption phase, undergoing a protonation reaction to generate ammonium salts.

[0033] This application achieves a wastewater ammonia nitrogen removal rate exceeding 80%, while simultaneously producing agricultural-grade ammonium sulfate (MVR crystallization purity ≥99.2%). This process saves 50% energy compared to traditional processes and eliminates secondary pollution. The cylindrical membrane reactor 15 regulates the microenvironment at the interface of the hollow fiber membrane 5, achieving a deamination flux of 12.5 kg / (m²·d), a threefold increase in efficiency compared to conventional gas stripping. This provides an environmentally friendly solution for cephalosporin antibiotic wastewater, combining deep denitrification with resource recovery.

[0034] The device and working principle / process of this application are as follows: high-concentration ammonium salt wastewater containing cephalosporin impurities is stored as mother liquor in a mother liquor tank 11. Sodium hydroxide solution is added to the mother liquor tank 11 through an alkali solution dosing tank 12 to adjust the alkalinity of the mother liquor in the mother liquor tank 11, and the pH value of the mother liquor in the mother liquor tank 11 is adjusted to above 11. After the alkalinity adjustment, the mother liquor is heated in a mother liquor preheater 13 to a temperature of 60°C.

[0035] The mother liquor after the temperature reaches 60°C and the alkali adjustment is completed enters the membrane filter 14. The filtration accuracy of the membrane filter 14 is 0.5μm, which can realize preliminary pre-filtration of the mother liquor. The filtered mother liquor is sent to the liquid inlet 1 of the columnar membrane reactor 15 through a booster pump and a PVC pipeline.

[0036] The sulfuric acid solution in the acid storage tank 16 is pumped to the acid inlet 2 of the columnar membrane reactor 15 by a booster pump.

[0037] The columnar membrane reactor 15 forms a uniform turbulent flow through the synergistic effect of the internal water distribution pipe 7 and the guide baffle 6. The hollow fiber membrane 5 in the columnar membrane reactor 15 can physically isolate the mother liquor after alkali adjustment from the sulfuric acid solution. The ammonium salt in the mother liquor after alkali adjustment will emit gaseous NH3 due to the alkaline high temperature environment. + , flows evenly through the water distribution holes of the water distribution pipe 7 through the hollow fiber membrane 5 made of polyvinylidene fluoride, and the sulfuric acid solution in the hollow fiber membrane 5 and the gaseous NH3 + The cephalosporin wastewater with low concentration of ammonium salt flows from the liquid outlet 4 to the deamination tank 12, thereby achieving the purpose of controlling the ammonium salt concentration in the cephalosporin wastewater and facilitating the subsequent coupling treatment with the biochemical system.

[0038] In the following examples, the columnar membrane reactor 15 was purchased from Hangzhou Hengfiltrate Technology Engineering Co., Ltd., model HF8X80T / W. The hollow fiber membrane 5 was a polyvinylidene fluoride membrane with an outer diameter of 300 μm to 350 μm, a pore size of 0.01 μm to 0.1 μm, and a porosity of 60% to 85%.

[0039] In the following examples, the ammonia nitrogen concentration was quantitatively analyzed using Nessler's reagent spectrophotometry (HJ 535-2009) using a μV-2700 UV-visible spectrophotometer.

[0040] Example 1

[0041] Pharmaceutical wastewater from an antibiotic production process in Lanzhou New District was selected. This wastewater contained ammonia nitrogen concentrations as high as 1800 mg / L, cephalosporins at 20 mg / L, compound antibiotics, and organic components. Its pH range was 5-7 (weakly acidic), and the wastewater was reddish-brown and transparent. The extremely high concentration of ammonium salts in this wastewater interacted synergistically with residual antibiotics, exerting a strong inhibitory effect on organic matter in the biochemical system. This made it difficult to directly treat this high-concentration ammonia nitrogen wastewater using a biochemical system.

[0042] First, the above-mentioned pharmaceutical wastewater is passed into the mother liquor pool 11, and sodium hydroxide solution is added to the mother liquor pool 11 through the alkali solution dosing tank 9. After the pH value of the pharmaceutical wastewater in the mother liquor pool 11 rises to 11, the addition of sodium hydroxide solution is stopped to obtain the pharmaceutical wastewater after the alkali adjustment is completed.

[0043] The pharmaceutical wastewater after alkali adjustment is introduced into the mother liquor preheater 13 by using the mother liquor preheater 13, and the introduced pharmaceutical wastewater is heated and the temperature is maintained after the pharmaceutical wastewater is heated to 60°C.

[0044] The pharmaceutical wastewater heated to 60° C. is passed through a membrane filter 14 with a pore size of 0.5 μm to finely filter the impurities in the pharmaceutical wastewater, thereby reducing the turbidity of the pharmaceutical wastewater and improving the water quality.

[0045] The pH value of the sulfuric acid solution contained in the liquid storage tank 16 is 0.5, and it is used as a deamination agent. The pharmaceutical wastewater and sulfuric acid solution after reducing the turbidity enter the columnar membrane reactor 15 through the corresponding liquid inlet 1 and acid inlet 2, respectively, and form a wastewater side and an acid absorption side on both sides of the hollow fiber membrane 5. The hollow fiber membrane 5 adopts a polyvinylidene fluoride membrane, and the pharmaceutical wastewater can be evenly distributed on the entire membrane through the liquid distribution holes of the water distribution pipe 7, so as to effectively volatilize the ammonium salt in the pharmaceutical wastewater and achieve the control of the ammonium salt concentration.

[0046] This embodiment utilizes a continuous flow treatment method. A pump (model BT1600F, brand Leifu, manufactured in China) continuously circulates sulfuric acid solution between the acid storage tank 16 and the columnar membrane reactor 15 at a circulation rate of 30 L / h. When the pH of the sulfuric acid solution in the acid storage tank 16 rises above 2, one-third of the sulfuric acid solution is withdrawn and replaced with sulfuric acid solution at a pH of 0.5 to maintain the pH of the sulfuric acid solution in the acid storage tank 16 and ensure the system's removal efficiency. The sulfuric acid solution withdrawn from the acid storage tank 16 is passed to the MVR evaporator 17, where its removal rate is calculated based on the amount of sulfuric acid added.

[0047] like Figure 2 As shown, a sample was taken from the liquid outlet 4 at an interval of 1 hour. At 0 min, the ammonia nitrogen concentration in the wastewater was 2139.29 mg / L. At 60 minutes, the ammonia nitrogen in the wastewater dropped to 549.91 mg / L. The pH in the acid solution was higher than 2, and the acid was replaced. At 120 minutes, the ammonia nitrogen in the wastewater was 436.98 mg / L. At 180 minutes, the ammonia nitrogen in the wastewater was 505.72 mg / L. At 240 minutes, the ammonia nitrogen in the wastewater was 556.46 mg / L. The pH in the acid solution was higher than 2, and the acid was replaced again. The pH of the wastewater dropped to 9.35. The treatment results are shown as follows: Figure 4 .

[0048] Although the foregoing describes specific embodiments of the present invention in detail, those skilled in the art will appreciate that these are for illustrative purposes only. The scope of protection of the present invention is defined by the appended claims. Without departing from the core principles and essential characteristics of the present invention, those skilled in the art may make various changes and modifications to the embodiments, and such changes and modifications are included in the scope of protection of the present invention.

Claims

1. A device for treating high-concentration ammonium salt wastewater using membrane technology, characterized in that: The device comprises: injecting high-concentration ammonium salt wastewater into a mother liquor pool (11), and adding alkaline solution in an alkali solution dosing tank (9) into the mother liquor pool (11) to adjust the pH of the high-concentration ammonium salt wastewater in the mother liquor pool (11) to above 11; the high-concentration ammonium salt wastewater after alkali adjustment is passed into a mother liquor preheater (13) and the temperature is raised to 60°C in the mother liquor preheater (13); the high-concentration ammonium salt wastewater after the temperature is raised to 60°C is sent to a membrane filter (14), and the high-concentration ammonium salt wastewater is pre-filtered by the membrane filter (14); the high-concentration ammonium salt wastewater after prefiltration is sent to a liquid inlet (1) at the bottom of a columnar membrane reactor (15) through a booster pump and a PVC pipeline, and the high-concentration ammonium salt wastewater is formed inside the columnar membrane reactor (15) through the synergistic action of an internal water distribution pipe (7) and a guide baffle (6). Uniform turbulence; the sulfuric acid solution in the acid storage tank (16) is reversely pumped in through the acid inlet (2) of the columnar membrane reactor (15) near the liquid inlet (1), and is physically isolated from the high-concentration ammonium salt wastewater after pre-filtration through the hydrophobic hollow fiber membrane (5) in the columnar membrane reactor (15), and a concentration gradient is formed on both sides of the hollow fiber membrane (5). Driven by the concentration gradient, NH3 in the high-concentration ammonium salt wastewater selectively penetrates the membrane pores and enters the sulfuric acid solution side to generate ammonium sulfate crystals, and the sulfuric acid solution after the generation of ammonium sulfate crystals passes through the acid outlet (3) and the circulation pipeline under the action of the pump body to return to the acid storage tank (16) for recycling; the low-concentration ammonium salt wastewater formed after treatment enters the deammonification tank (12) through the liquid outlet (4) at the top of the columnar membrane reactor (15) so as to be coupled with the subsequent biochemical system for treatment.

2. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 1, wherein: The filtration accuracy of the membrane filter (14) is 0.5 μm. The material of the hydrophobic hollow fiber membrane (5) in the columnar membrane reactor (15) is polyvinylidene fluoride. The inner diameter of the membrane pore of the hollow fiber membrane (5) is 0.01 μm~0.1 μm and the porosity is 60~85%. The hollow fiber membrane (5) is woven by membrane wire through a mesh weaving process, and the membrane wire woven by the mesh weaving process is then rolled on the surface of the water distribution pipe (7). A plurality of water distribution holes are distributed on the water distribution pipe (7).

3. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 1, wherein: The alkaline solution in the alkali solution dosing tank (9) is a sodium hydroxide solution. After the sodium hydroxide solution is added to the mother liquor tank (11), the alkali is adjusted by mechanical stirring.

4. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 3, wherein: The mass concentration of the sodium hydroxide solution is 30% to 32%.

5. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 1, characterized in that: The ammonia nitrogen concentration of the high-concentration ammonium salt wastewater is 1500 mg / L~2000 mg / L.

6. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 5, characterized in that: The ammonia nitrogen concentration of the high-concentration ammonium salt wastewater is 1800 mg / L~2000 mg / L.

7. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 1, characterized in that: The pH value of the sulfuric acid solution is 0.1-0.

5.

8. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 7, characterized in that: The pH value of the sulfuric acid solution is 0.

5.

9. The device for treating high-concentration ammonium salt wastewater using membrane technology according to claim 1, characterized in that: The acid storage tank (16) and the mother liquor pool (11) are both provided with pH monitors (10) to monitor the pH values ​​of the acid storage tank (16) and the mother liquor pool (11); the saturated sulfuric acid solution in the acid storage tank (16) is recovered by an MVR evaporation device (17) to recover ammonium salt.

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