Ammonia-nitrogen wastewater treatment method

Abstract

The invention relates to the technical field of wastewater treatment, in particular to an ammonia-nitrogen wastewater treatment method.A composite modified zeolite material has excellent physical adsorption capacity on ammonia nitrogen by means of the unique pore structure and surface property of the composite modified zeolite material, ammonia nitrogen molecules in wastewater can be rapidly captured, and the ammonia nitrogen wastewater treatment effect is improved. Then, under the synergistic effect of illumination and ultrasonic waves, free radicals with strong oxidizing property are generated through the composite photocatalyst, ammonia nitrogen molecules which are not completely adsorbed by the zeolite material are deeply degraded, and the removal efficiency of ammonia nitrogen is remarkably improved through the synergistic effect of adsorption and photocatalysis; after adsorption and photocatalysis treatment, the concentration of ammonia nitrogen in the wastewater is greatly reduced, then resin adsorption treatment is adopted as a subsequent step, and residual trace ammonia nitrogen and other impurities can be selectively adsorbed, so that deep purification of the wastewater is realized, and the effluent quality is ensured to reach or be superior to related emission standards.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and particularly relates to a method for treating ammonia nitrogen wastewater. Background Art

[0002] With the acceleration of the global industrialization process and the continuous growth of the population scale, various industrial production activities and human lives continuously generate a large amount of wastewater containing ammonia nitrogen. The problem of ammonia nitrogen wastewater pollution has become one of the key environmental challenges restricting the sustainable development of the ecological environment and threatening human health and safety. In the process of chemical production, many chemical reactions use ammonia-containing raw materials or intermediates, and the wastewater after the reaction often contains a high concentration of ammonia nitrogen; in the pharmaceutical industry, in the links of drug synthesis and extraction, due to the use of nitrogen-containing organic compounds, the ammonia nitrogen content in the generated wastewater is also relatively high; in the food processing industry, such as meat processing and soybean product processing, a large amount of ammonia nitrogen produced by protein decomposition will be brought in during the raw material cleaning and processing wastewater discharge process; the ammonia-containing tanning agents used in the leather tanning industry also keep the ammonia nitrogen concentration in the wastewater at a high level.

[0003] Currently, the commonly used methods for treating ammonia nitrogen wastewater include physical methods, chemical methods, biological methods, etc. However, these methods have problems such as low treatment efficiency, high cost, and easy generation of secondary pollution. Therefore, researching a composite treatment method that combines multiple treatment technologies to improve the treatment efficiency and purification effect of ammonia nitrogen wastewater has become an urgent technical problem in this field. Summary of the Invention

[0004] Technical Problem to be Solved In view of the above-mentioned disadvantages of the prior art, the present invention provides a method for treating ammonia nitrogen wastewater, which can effectively solve the technical defects of the existing methods for treating ammonia nitrogen wastewater, such as low treatment efficiency, high cost, and easy generation of secondary pollution.

[0005] Technical Solution To achieve the above object, the present invention is realized through the following technical solutions: A method for treating ammonia nitrogen wastewater, the treatment method is as follows: S1. Add a composite modified zeolite material to the ammonia nitrogen wastewater, then perform an oscillation treatment. After standing for 1 - 2 h, filter the supernatant to obtain the adsorption treatment component; S2. Adjust the pH value of the adsorption treatment component to 10 - 11, then add a composite photocatalyst, and perform photocatalytic treatment under ultrasonic vibration conditions to obtain the degradation component; S3. Adjust the pH value of the degradation component to 7 with a 1 mol / L hydrochloric acid solution, and then perform resin adsorption treatment to complete the treatment of ammonia nitrogen wastewater.

[0006] Furthermore, the input amount in S1 is 2 - 12 g / L, and the oscillation treatment method in S1 is to oscillate at a power of 100 W for 10 min.

[0007] Furthermore, the preparation steps of the composite modified zeolite material in S1 are as follows: Step A: Crush natural zeolite and then pass it through a 200 - mesh sieve. Then, add it to a 1 mol / L sodium chloride solution according to a solid - liquid ratio of 1:10, stir at a speed of 300 r / min at a temperature of 25°C for 12 h, let it stand for 12 h, and then centrifuge at a speed of 7000 r / min for 10 min. After rinsing the centrifuged precipitate with deionized water until neutral, the obtained product is denoted as the salt - treated component; Step B: Place the salt - treated component in an oven at 105°C and dry it to a constant weight. Then, place it in a muffle furnace at 450°C and calcine it for 1 h. After taking it out and cooling to room temperature, the obtained product is the composite modified zeolite material.

[0008] Furthermore, the filtration treatment method in S1 is to circulate - filter with a polyethersulfone hollow - fiber ultrafiltration membrane for 2 - 3 h.

[0009] Furthermore, in S2, the pH value of the adsorption - treated component is adjusted with a 1 mol / L sodium hydroxide solution, and the input amount of the composite photocatalyst in S2 is 0.5 - 1 g / L.

[0010] Furthermore, the preparation steps of the composite photocatalyst in S2 are as follows: Step 1: Place 10 g of melamine in a muffle furnace, heat it up to 600°C, keep it at this temperature for 2 h, then cool it to room temperature. After grinding, place it in the muffle furnace again and anneal it at 550°C for 3 h. After cooling to room temperature, the obtained product is denoted as the pretreatment component; Step 2: Immerse the pretreatment component in a saturated boric acid solution, stir it, and then perform freeze - drying. Then, place it in a tube furnace under a nitrogen atmosphere, heat it up to 550°C, keep it at this temperature for 2 h, cool it to room temperature, and wash it with distilled water 3 - 5 times. After drying, it is denoted as the nano - mesh component; Step 3: Weigh 5 - 6 g of zinc sulfate heptahydrate and disperse it in 600 mL of sodium hydroxide solution. After stirring and dispersing, add 3 - 4 g of the nano - mesh component, then add 90 mL of ammonia water and continue to stir for 30 min. Then, react in a high - pressure reactor at 90°C for 6 h. The obtained product is denoted as the reaction component; Step 4: Centrifuge the reaction component at a speed of 6000 r / min for 10 min, rinse the centrifuged precipitate with deionized water and absolute ethanol 3 times in sequence, and then perform drying treatment. The obtained product is the composite photocatalyst.

[0011] Further, the heating rate for heating up in Step 1 is 2 °C / min, the annealing rate for annealing in Step 1 is 2 °C / min, the stirring treatment method in Step 2 is to stir at a rotation speed of 500 r / min for 30 min, the heating rate for heating up in Step 2 is 2.3 °C / min, and the drying treatment method in Step 2 is to dry at a temperature of 80 °C until constant weight.

[0012] Further, the concentration of the sodium hydroxide solution in Step 3 is 0.5 mol / L, the stirring and dispersing method in Step 3 is to stir at a rotation speed of 500 r / min for 30 min, and the drying treatment method in Step 4 is to dry at a temperature of 80 - 85 °C until constant weight.

[0013] Further, the ultrasonic power of the ultrasonic vibration condition in S2 is 50 W, the ultrasonic frequency is 40 kHz, the light source for the photocatalytic treatment in S2 is a 300 W xenon lamp, the fixed position of the light source is 15 cm above the liquid level, and the catalytic treatment time is 2 - 3 h.

[0014] Further, the resin adsorption treatment method in S3 is as follows: Add the adsorption resin into the degradation component with a pH value of 7 at an input amount of 20 - 40 g / L, stir at a rotation speed of 150 r / min at a temperature of 25 °C for 2 - 3 h, then let it stand for 3 - 5 h for adsorption, and complete the resin adsorption treatment after removing the adsorption resin.

[0015] Beneficial effects The present invention provides a method for treating ammonia - nitrogen wastewater. Compared with the existing well - known technologies, the present invention has the following beneficial effects: 1. Due to its unique pore structure and surface properties, the composite modified zeolite material in the present invention has excellent physical adsorption ability for ammonia - nitrogen, and can quickly capture ammonia - nitrogen molecules in the wastewater. Then, under the synergistic action of light and ultrasonic waves by the composite photocatalyst, strongly oxidizing free radicals are generated to deeply degrade the ammonia - nitrogen molecules not completely adsorbed by the zeolite material. Through the synergistic action of adsorption and photocatalysis, the removal efficiency of ammonia - nitrogen is significantly improved; after adsorption and photocatalytic treatment, the ammonia - nitrogen concentration in the wastewater has been greatly reduced. Then, using resin adsorption treatment as a subsequent step can selectively adsorb residual trace ammonia - nitrogen and other impurities, thereby realizing the deep purification of the wastewater and ensuring that the effluent quality meets or exceeds relevant discharge standards.

[0016] 2. The composite modified zeolite material and the composite photocatalyst used in the present invention are both non-toxic and harmless environmentally friendly materials, which will not produce toxic and harmful substances during the preparation and use processes, are environmentally friendly, conform to the concept of sustainable development, and the waste generated during the treatment process, such as the saturated zeolite material and resin, can be treated through simple regeneration or safe disposal methods, thus avoiding the generation of secondary pollution. Secondly, the raw materials for preparing the composite modified zeolite material and the composite photocatalyst are widely sourced and have low costs, and can still maintain good performance after being used multiple times, and can be reused through regeneration treatment, thereby further reducing the treatment cost. Detailed Embodiment

[0017] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] The present invention will be further described below in conjunction with embodiments.

[0019] The sources of some components in the examples and comparative examples are as follows: Natural zeolite, produced in Wenshan, Yunnan; Sodium chloride, Zhengzhou Chunqiu Chemical Co., Ltd.; The average relative molecular mass of the polyethersulfone hollow fiber ultrafiltration membrane is 60,000, the cut-off pore size is 0.1 - 0.3 μm, and the cut-off relative molecular mass is 3,000 - 20,000, Hangzhou Aoke Filtration Technology Co., Ltd.; Melamine, Sinopharm Chemical Reagent Co., Ltd.; Boric acid, Sinopharm Chemical Reagent Co., Ltd.; Zinc sulfate heptahydrate, Sinopharm Chemical Reagent Co., Ltd.; Sodium hydroxide, Sinopharm Chemical Reagent Co., Ltd.; Absolute ethanol, Sinopharm Chemical Reagent Co., Ltd.; Hydrochloric acid, Sinopharm Chemical Reagent Co., Ltd.; Adsorption resin, strongly polar AH-0 resin.

[0020] Example 1 A method for treating ammonia-nitrogen wastewater in this example has the following treatment method: S1. After adding the composite modified zeolite material to the ammonia-nitrogen wastewater at an input amount of 2 g / L, oscillate it at a power of 100 W for 10 min, let it stand for 1 h, and then circulate and filter the supernatant with the polyethersulfone hollow fiber ultrafiltration membrane for 2 h, and the obtained is denoted as the adsorption treatment component; Among them, the preparation steps of the composite modified zeolite material are as follows: Step A: Crush natural zeolite and then pass it through a 200-mesh sieve. Then, put it into a sodium chloride solution with a concentration of 1 mol / L according to a solid-liquid ratio of 1:10, stir it at a speed of 300 r / min at a temperature of 25 °C for 12 h, let it stand for 12 h, and then centrifuge it at a speed of 7000 r / min for 10 min. After rinsing the centrifuged precipitate with deionized water until it is neutral, the obtained product is denoted as the salt-treated component; Step B: Place the salt-treated component in an oven at 105 °C and dry it to a constant weight. Then, place it in a muffle furnace at 450 °C and calcine it for 1 h. After taking it out and cooling it to room temperature, the obtained product is the composite modified zeolite material.

[0021] S2: After adjusting the pH value of the adsorption-treated component to 10 with a sodium hydroxide solution with a concentration of 1 mol / L, add the composite photocatalyst according to an input amount of 0.5 g / L, and carry out photocatalytic treatment under ultrasonic vibration conditions. The obtained product is denoted as the degradation component; Among them, the preparation steps of the composite photocatalyst are as follows: Step 1: Place 10 g of melamine in a muffle furnace and heat it up to 600 °C at a heating rate of 2 °C / min, keep it warm for 2 h, and then cool it to room temperature. After grinding, place it in the muffle furnace again and anneal it at a temperature of 550 °C at an annealing rate of 2 °C / min for 3 h. After cooling to room temperature, the obtained product is denoted as the pre-treated component; Step 2: Immerse the pre-treated component in a saturated boric acid solution, stir it at a speed of 500 r / min for 30 min, and then carry out freeze-drying. Then, place it in a tube furnace under a nitrogen atmosphere and heat it up to 550 °C at a heating rate of 2.3 °C / min and keep it warm for 2 h. After cooling to room temperature, wash it 3 times with distilled water, and place it at a temperature of 80 °C and dry it to a constant weight, which is denoted as the nano-network component; Step 3: Weigh 5 g of zinc sulfate heptahydrate and disperse it in 600 mL of a sodium hydroxide solution with a concentration of 0.5 mol / L. Stir it at a speed of 500 r / min for 30 min, then add 3 g of the nano-network component, add 90 mL of ammonia water, and continue to stir for 30 min. Then, react it in a high-pressure reactor at 90 °C for 6 h. The obtained product is denoted as the reaction component; Step 4: Centrifuge the reaction component at a speed of 6000 r / min for 10 min, wash the centrifuged precipitate with deionized water and absolute ethanol 3 times in sequence, and then place it at a temperature of 80 °C and dry it to a constant weight. The obtained product is the composite photocatalyst.

[0022] In S2, the ultrasonic power of the ultrasonic vibration condition is 50 W, the ultrasonic frequency is 40 kHz, the light source for photocatalytic treatment is a 300-W xenon lamp, the fixed position of the light source is 15 cm above the liquid level, and the catalytic treatment time is 2 h.

[0023] S3. Adjust the pH value of the degradation component to 7 with a hydrochloric acid solution at a concentration of 1 mol / L, and then perform resin adsorption treatment to complete the treatment of ammonia nitrogen wastewater.

[0024] Among them, the method of resin adsorption treatment is as follows: Add the adsorption resin into the degradation component with a pH value of 7 at an input amount of 20 g / L, stir at a speed of 150 r / min at a temperature of 25°C for 2 h, and then stand still for 3 h for adsorption. After removing the adsorption resin, the resin adsorption treatment is completed.

[0025] Example 2 A method for treating ammonia nitrogen wastewater in this example, the treatment method is as follows: S1. Add the composite modified zeolite material into the ammonia nitrogen wastewater at an input amount of 12 g / L, oscillate at a power of 100 W for 10 min, stand still for 2 h, and then circulate and filter the supernatant with a polyethersulfone hollow fiber ultrafiltration membrane for 3 h. The obtained is denoted as the adsorption treatment component; Among them, the preparation steps of the composite modified zeolite material are as follows: Step A. Crush natural zeolite and pass it through a 200-mesh sieve, then add it into a sodium chloride solution with a concentration of 1 mol / L at a solid-liquid ratio of 1:10, stir at a speed of 300 r / min at a temperature of 25°C for 12 h, stand still for 12 h, centrifuge at a speed of 7000 r / min for 10 min, and wash the centrifuged precipitate with deionized water until neutral. The obtained is denoted as the salt treatment component; Step B. Dry the salt treatment component in an oven at 105°C until constant weight, then calcine it in a muffle furnace at 450°C for 1 h. After taking it out and cooling to room temperature, the obtained is the composite modified zeolite material.

[0026] S2. After adjusting the pH value of the adsorption treatment component to 11 with a sodium hydroxide solution at a concentration of 1 mol / L, add the composite photocatalyst at an input amount of 1 g / L, and perform photocatalytic treatment under ultrasonic vibration conditions. The obtained is denoted as the degradation component; Among them, the preparation steps of the composite photocatalyst are as follows: Step 1. Place 10 g of melamine in a muffle furnace, heat it at a heating rate of 2°C / min to 600°C, keep it warm for 2 h, then cool it to room temperature, grind it, and then place it in the muffle furnace again and anneal it at a temperature of 550°C at an annealing rate of 2°C / min for 3 h. After cooling to room temperature, the obtained is denoted as the pretreatment component; Step 2. Immerse the pretreatment component in a saturated boric acid solution, stir at a speed of 500 r / min for 30 min, then perform freeze-drying, then place it in a tube furnace under a nitrogen atmosphere, heat it at a heating rate of 2.3°C / min to 550°C and keep it warm for 2 h, cool it to room temperature, wash it 5 times with distilled water, and dry it at a temperature of 80°C until constant weight. The obtained is denoted as the nano-network component; Step 3: Weigh 6 g of zinc sulfate heptahydrate and disperse it in 600 mL of sodium hydroxide solution with a concentration of 0.5 mol / L. Stir it at a speed of 500 r / min for 30 min, then add 4 g of the nano-network component. After adding 90 mL of ammonia water, continue to stir for 30 min. Then react it in a high-pressure reactor at 90 °C for 6 h. The obtained product is denoted as the reaction component. Step 4: Centrifuge the reaction component at a speed of 6000 r / min for 10 min. Wash the centrifuged precipitate successively with deionized water and absolute ethanol three times, and then dry it at 85 °C until constant weight. The obtained product is the composite photocatalyst.

[0027] In S2, the ultrasonic power of the ultrasonic vibration condition is 50 W, the ultrasonic frequency is 40 kHz, the light source for photocatalytic treatment is a 300 W xenon lamp, the fixed position of the light source is 15 cm above the liquid level, and the catalytic treatment time is 3 h.

[0028] S3: Adjust the pH value of the degradation component to 7 with a 1 mol / L hydrochloric acid solution, and then perform resin adsorption treatment to complete the treatment of ammonia nitrogen wastewater.

[0029] Among them, the method of resin adsorption treatment is as follows: Add the adsorption resin into the degradation component with a pH value of 7 at an input amount of 40 g / L. Stir it at a speed of 150 r / min at 25 °C for 3 h, and then let it stand for 5 h for adsorption. After removing the adsorption resin, the resin adsorption treatment is completed.

[0030] Example 3 A method for treating ammonia nitrogen wastewater in this example, the treatment method is as follows: S1: Add the composite modified zeolite material into the ammonia nitrogen wastewater at an input amount of 7 g / L, oscillate it at a power of 100 W for 10 min, let it stand for 2 h, and then circulate and filter the supernatant with a polyethersulfone hollow fiber ultrafiltration membrane for 3 h. The obtained product is denoted as the adsorption treatment component. Among them, the preparation steps of the composite modified zeolite material are as follows: Step A: Crush natural zeolite and pass it through a 200-mesh sieve. Then add it into a 1 mol / L sodium chloride solution according to a solid-liquid ratio of 1:10. Stir it at a speed of 300 r / min at 25 °C for 12 h, let it stand for 12 h, and then centrifuge it at a speed of 7000 r / min for 10 min. Wash the centrifuged precipitate with deionized water until it is neutral. The obtained product is denoted as the salt treatment component. Step B: Dry the salt treatment component in an oven at 105 °C until constant weight, then calcine it in a muffle furnace at 450 °C for 1 h. After taking it out and cooling it to room temperature, the obtained product is the composite modified zeolite material.

[0031] S2. After adjusting the pH value of the adsorption treatment component to 11 with a 1 mol / L sodium hydroxide solution, add the composite photocatalyst at an input amount of 0.8 g / L, and perform photocatalytic treatment under ultrasonic vibration conditions. The obtained product is denoted as the degradation component; Among them, the preparation steps of the composite photocatalyst are as follows: Step 1. Place 10 g of melamine in a muffle furnace, heat it up to 600 °C at a heating rate of 2 °C / min, keep it warm for 2 h, then cool it to room temperature. After grinding, place it in the muffle furnace again and anneal it at 550 °C at an annealing rate of 2 °C / min for 3 h. After cooling to room temperature, the obtained product is denoted as the pretreatment component; Step 2. Immerse the pretreatment component in a saturated boric acid solution, stir it at a rotation speed of 500 r / min for 30 min, then perform freeze-drying. Then place it in a tube furnace under a nitrogen atmosphere and heat it up to 550 °C at a heating rate of 2.3 °C / min, keep it warm for 2 h. After cooling to room temperature, wash it 4 times with distilled water, and dry it at 80 °C until constant weight. The obtained product is denoted as the nano-network component; Step 3. Weigh 6 g of zinc sulfate heptahydrate and disperse it in 600 mL of a 0.5 mol / L sodium hydroxide solution. Stir it at a rotation speed of 500 r / min for 30 min, then add 4 g of the nano-network component, add 90 mL of ammonia water, and continue to stir for 30 min. Then react in a high-pressure reactor at 90 °C for 6 h. The obtained product is denoted as the reaction component; Step 4. Centrifuge the reaction component at a rotation speed of 6000 r / min for 10 min, wash the centrifugal precipitate 3 times successively with deionized water and absolute ethanol, and then dry it at 82 °C until constant weight. The obtained product is the composite photocatalyst.

[0032] In S2, the ultrasonic power under the ultrasonic vibration conditions is 50 W, the ultrasonic frequency is 40 kHz, the light source for photocatalytic treatment is a 300 W xenon lamp, the fixed position of the light source is 15 cm above the liquid level, and the catalytic treatment time is 3 h.

[0033] S3. Adjust the pH value of the degradation component to 7 with a 1 mol / L hydrochloric acid solution, and then perform resin adsorption treatment to complete the treatment of ammonia nitrogen wastewater.

[0034] Among them, the method of resin adsorption treatment is as follows: Add the adsorption resin to the degradation component with a pH value of 7 at an input amount of 30 g / L, stir it at a rotation speed of 150 r / min at 25 °C for 3 h, then let it stand for 4 h for adsorption. After removing the adsorption resin, the resin adsorption treatment is completed.

[0035] Comparative Example 1 A method for treating ammonia nitrogen wastewater provided in this comparative example is generally the same as that in Example 1, and the main difference is that: in this comparative example, the composite modified zeolite material in Example 1 is replaced with natural zeolite that has been pulverized and passed through a 200-mesh sieve.

[0036] Comparative Example 2 A method for treating ammonia nitrogen wastewater provided in this comparative example is generally the same as that in Example 1, and the main difference is that: in this comparative example, the composite photocatalyst in Example 1 is replaced with nano-zinc oxide.

[0037] Comparative Example 3 A method for treating ammonia nitrogen wastewater provided in this comparative example is generally the same as that in Example 1, and the main difference is that: in this comparative example, the resin adsorption treatment in Example 1 is not carried out.

[0038] Performance Test The treatment results of the ammonia nitrogen wastewater treatment methods in Examples 1-3 and Comparative Examples 1-3 were detected. The ammonia nitrogen degradation rate of the wastewater treated by the ammonia nitrogen wastewater treatment methods in Examples 1-3 and Comparative Examples 1-3 was measured by the Nessler's reagent spectrophotometry method, and the obtained data were recorded in the following table; It can be seen from the data in the above table that the ammonia nitrogen degradation rate of the wastewater treated by the ammonia nitrogen wastewater treatment methods in Examples 1-3 of the present invention is significantly higher than that in Comparative Examples 1-3, indicating that by adsorbing and photocatalytically treating and then using resin adsorption treatment in the present invention, the ammonia nitrogen in the ammonia nitrogen wastewater can be better degraded, and a better wastewater purification effect can be achieved.

[0039] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0040] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements will not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for treating ammonia nitrogen wastewater, characterized in that, The treatment method is as follows: S1. Add the composite modified zeolite material to the ammonia-nitrogen wastewater, then conduct oscillating treatment. After standing for 1 - 2 h, filter the supernatant. The obtained filtrate is denoted as the adsorption treatment component; S2. Adjust the pH value of the adsorption treatment component to 10 - 11, then add the composite photocatalyst, and conduct photocatalytic treatment under ultrasonic vibration conditions. The obtained product is denoted as the degradation component; S3. Adjust the pH value of the degradation component to 7 with a hydrochloric acid solution with a concentration of 1 mol / L, and then conduct resin adsorption treatment to complete the treatment of ammonia-nitrogen wastewater.

2. The ammonia nitrogen wastewater treatment method according to claim 1, characterized in that, The input amount in S1 is 2 - 12 g / L, and the oscillating treatment method in S1 is to oscillate at a power of 100 W for 10 min.

3. The ammonia nitrogen wastewater treatment method according to claim 1, characterized in that, The preparation steps of the composite modified zeolite material in S1 are as follows: Step A. Crush natural zeolite and pass it through a 200-mesh sieve. Then, add it to a sodium chloride solution with a concentration of 1 mol / L according to a solid-liquid ratio of 1:10, stir at a speed of 300 r / min at a temperature of 25°C for 12 h, stand for 12 h, then centrifuge at a speed of 7000 r / min for 10 min, and rinse the centrifugal precipitate with deionized water until it is neutral. The obtained product is denoted as the salt treatment component; Step B. Dry the salt treatment component in an oven at 105°C until it reaches a constant weight, then calcine it in a muffle furnace at 450°C for 1 h. After taking it out and cooling to room temperature, the obtained product is the composite modified zeolite material.

4. A method for treating ammonia nitrogen wastewater according to claim 1, characterized in that, The filtration treatment method in S1 is to circulate and filter with a polyethersulfone hollow fiber ultrafiltration membrane for 2 - 3 h.

5. A method for treating ammonia nitrogen wastewater according to claim 1, characterized in that, In S2, the pH value of the adsorption treatment component is adjusted with a sodium hydroxide solution with a concentration of 1 mol / L, and the input amount of the composite photocatalyst in S2 is 0.5 - 1 g / L.

6. A method for treating ammonia nitrogen wastewater according to claim 1, characterized in that, The preparation steps of the composite photocatalyst in S2 are as follows: Step 1. Place 10 g of melamine in a muffle furnace, heat it up to 600°C at a heating rate of 2°C / min, keep it at this temperature for 2 h, then cool it to room temperature. After grinding, place it in the muffle furnace again and anneal it at 550°C for 3 h at an annealing rate of 2°C / min. After cooling to room temperature, the obtained product is denoted as the pretreatment component; Step 2. Immerse the pretreatment component in a saturated boric acid solution, stir it, then conduct freeze-drying. Then, place it in a tubular furnace under a nitrogen atmosphere, heat it up to 550°C at a heating rate of 2.3°C / min, keep it at this temperature for 2 h, cool it to room temperature, wash it with distilled water 3 - 5 times, and conduct drying treatment. The obtained product is denoted as the nano-network component; Step 3. Weigh 5 - 6 g of zinc sulfate heptahydrate, disperse it in 600 mL of sodium hydroxide solution, stir and disperse it, then add 3 - 4 g of the nano-network component, then add 90 mL of ammonia water, and continue to stir for 30 min. Then, react in a high-pressure reaction kettle at 90°C for 6 h. The obtained product is denoted as the reaction component; Step 4. Centrifuge the reaction component at a speed of 6000 r / min for 10 min, rinse the centrifugal precipitate with deionized water and absolute ethanol 3 times in sequence, and then conduct drying treatment. The obtained product is the composite photocatalyst.

7. A method for treating ammonia nitrogen wastewater according to claim 6, characterized in that, In Step 1, the heating rate of heating up is 2°C / min, the annealing rate of annealing in Step 1 is 2°C / min, the stirring treatment method in Step 2 is to stir at a speed of 500 r / min for 30 min, the heating rate of heating up in Step 2 is 2.3°C / min, and the drying treatment method in Step 2 is to dry at a temperature of 80°C until it reaches a constant weight.

8. A method for treating ammonia nitrogen wastewater according to claim 6, characterized in that, In step 3, the concentration of the sodium hydroxide solution is 0.5 mol / L. The method of stirring and dispersing in step 3 is to stir at a speed of 500 r / min for 30 min. The method of drying treatment in step 4 is to dry at a temperature of 80 - 85 °C until constant weight.

9. A method for treating ammonia nitrogen wastewater according to claim 1, characterized in that, In S2, the ultrasonic power of the ultrasonic vibration condition is 50 W, and the ultrasonic frequency is 40 kHz. The light source for photocatalytic treatment in S2 is a 300 W xenon lamp. The fixed position of the light source is 15 cm above the liquid level, and the time for catalytic treatment is 2 - 3 h.

10. A method for treating ammonia nitrogen wastewater according to claim 1, characterized in that, The method of resin adsorption treatment in S3 is as follows: Add the adsorption resin into the degradation component with a pH value of 7 at an input amount of 20 - 40 g / L, stir at a speed of 150 r / min at a temperature of 25 °C for 2 - 3 h, then let it stand for 3 - 5 h for adsorption. After removing the adsorption resin, the resin adsorption treatment is completed.

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