Method for treating high ammonia-nitrogen wastewater and recycling

Abstract

This invention discloses a method for treating and recycling high-ammonia nitrogen wastewater. The method comprises the following steps: (1) inoculating microalgae into a nitrogen-free TAP medium and subjecting them to nitrogen starvation acclimatization culture for 4-6 days; (2) adding zeolite to the high-ammonia nitrogen wastewater to reduce the TAN concentration to 200-300 mg / L; (3) co-culturing the nitrogen-starved microalgae with yeast to treat the wastewater obtained in step (2), while simultaneously adjusting the pH of the wastewater to 6.0-7.0 daily. After 6-8 days of treatment, the resulting wastewater exhibits a TAN removal rate of over 95% compared to the treated high-ammonia nitrogen wastewater. This invention can treat aquaculture wastewater with high nutrient levels, particularly aquaculture wastewater containing high ammonia nitrogen and organic matter, and achieve wastewater resource recycling to reduce costs and improve economic efficiency.

Description

Technical fields:

[0001] This invention relates to the field of ammonia nitrogen wastewater treatment technology, specifically to a method for treating and recycling high-ammonia nitrogen wastewater. Background technology:

[0002] With the rapid development of global livestock farming, a large amount of nutrient-rich wastewater has been generated. The concentrations of chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen (TN), total ammonia nitrogen (TAN), and total phosphorus (TP) in this wastewater reach 7786, 2094, 2048, 1820, and 124.7 mg / L, respectively. High concentrations of TAN and TOC can negatively impact the efficiency, stability, and safety of traditional treatment technologies, including chemical and biological methods. Developing new high-carbon and high-nitrogen wastewater treatment technologies is crucial for the resource-based treatment of livestock wastewater.

[0003] To offset treatment costs and achieve resource recycling, nutrient recovery can be performed during wastewater treatment to produce high-value biomass. As a prominent example of "turning waste into treasure," microalgae, with their excellent nutrient assimilation capabilities and high-value components, have been widely cultivated for wastewater treatment. Microalgae can efficiently assimilate carbon, nitrogen, phosphorus, and various trace elements in wastewater to reduce the discharge of high-carbon and high-nitrogen wastewater. Simultaneously, microalgae can utilize carbon dioxide for photosynthesis to produce oxygen, aligning with the low-carbon and environmentally friendly goals of wastewater resource utilization. Furthermore, cultivating microalgae in wastewater can produce high-value components at relatively low operating costs, including proteins, carotene, astaxanthin, polyunsaturated fatty acids, and phycocyanin, which can be used in animal feed to improve the quality of agricultural and livestock products. Therefore, sustainable wastewater resource utilization technologies based on microalgae are gradually becoming a focus of attention.

[0004] Nitrogen plays a crucial role in protein synthesis and determines the nutritional value of harvested biomass in animal feed; therefore, nitrogen recovery from microalgae is essential for the resource utilization of aquaculture wastewater. However, nitrogen recovery in microalgae-based wastewater resource utilization is limited by several issues, including long treatment cycles, ammonia toxicity, and low nitrogen recovery rates. Firstly, the long operating cycle (14-20 days) of microalgae-based aquaculture wastewater resource utilization not only increases total investment and operating costs but also easily leads to bacterial contamination. Therefore, in industrial applications, traditional technologies with shorter treatment cycles, such as sequencing batch reactors (SBRs) activated sludge processes and anaerobic-anoxic-anoxic processes, are more widely used in aquaculture wastewater resource utilization compared to microalgae technology. However, these traditional technologies generate large amounts of sludge that require further treatment, and it is difficult to recover high-value components. On the other hand, high concentrations of ammonia nitrogen in aquaculture wastewater increase intracellular oxidative stress, hinder photosynthesis, and even lead to microalgae culture failure, thus restricting algal cell growth. To control ammonia toxicity, freshwater dilution or ammonia stripping has been widely used in the pretreatment of aquaculture wastewater. However, the high freshwater consumption caused by wastewater dilution and the nitrogen loss due to ammonia stripping do not align with the principles of a circular economy. Furthermore, microalgae cultivation for wastewater resource recovery primarily focuses on denitrification efficiency, neglecting the recovery ratio of nitrogen from wastewater to microbial biomass. Although Chlorella cultivation achieved removal rates of 86.80%, 86.64%, 84.99%, and 100% for TAN, TN, COD, and TP in pig manure pretreatment, respectively, the proportion of nitrogen assimilated by microalgae is unclear, and ammonia nitrogen volatilization losses due to pH increases during cultivation remain significant. Moreover, ammonia volatilization increases the carbon-to-nitrogen ratio, inducing lipid production rather than protein formation, thus hindering its use in animal feed. Therefore, a thorough understanding and improvement of the nitrogen migration process from wastewater to microbial biomass in microalgae-based aquaculture wastewater resource recovery are crucial to increasing the protein content in microalgae. Summary of the Invention:

[0005] In order to overcome the above-mentioned problems in the existing technology, the present invention provides a method for treating and recycling high ammonia nitrogen wastewater. This method can treat aquaculture wastewater with high nutrient elements, especially aquaculture wastewater containing high ammonia nitrogen and organic matter, and realize wastewater resource utilization to reduce costs and improve economic benefits.

[0006] The first objective of this invention is to provide a method for treating and recycling high-ammonia-nitrogen wastewater, comprising the following steps:

[0007] (1) Microalgae were inoculated in TAP medium without nitrogen source and subjected to nitrogen starvation acclimatization culture for 3-6 days. The culture temperature, light intensity, shaking speed and light-dark cycle were set to 22℃-30℃, 100-200μmol / m·s, 80-150rpm and 12 / 12-16 / 8h, respectively.

[0008] (2) Add zeolite to the high ammonia nitrogen wastewater to reduce the TAN concentration (total ammonia nitrogen concentration) of the high ammonia nitrogen wastewater to 200-300 mg / L;

[0009] (3) Microalgae and yeast that have undergone nitrogen starvation acclimatization are co-cultured at a mass ratio of 4:1 to 1:1 to treat the wastewater obtained in step (2). At the same time, the pH value of the wastewater is adjusted to 6.0-7.0 every day. After 6-8 days of treatment, the wastewater obtained has a TAN removal rate of more than 95% compared with the high ammonia nitrogen wastewater to be treated.

[0010] Step (1) involves nitrogen starvation acclimatization for only 3-6 days to prevent microalgae from excessively decomposing intracellular proteins and dying. Nitrogen-starved microalgae improved nitrogen removal efficiency in aquaculture wastewater with TAN concentration adjusted to 200-300 mg / L using an aeration device to 39.86-77.33 mg / L / day. Nitrogen-starved microalgae were recovered by centrifugation at 5000g for further experiments. In step (3), after co-culturing microalgae with yeast for 6-8 days, a biomass greater than 4 g / L was achieved, and the removal rates of TOC, TN, TAN, and TP were all greater than 75%, with the TAN removal rate reaching over 95%.

[0011] Preferably, the TAP culture medium in step (1) comprises the following components: 20 mM tris(hydroxymethyl)aminomethane, 17 mM glacial acetic acid, 0.69 mM disodium hydrogen phosphate, 0.45 mM dipotassium dihydrogen phosphate, 0.4 mM magnesium sulfate, 0.35 mM calcium chloride, 1 mL / L Hunter's trace elements, and the remainder being deionized water.

[0012] Preferably, the concentration of microalgae cells inoculated in the culture medium in step (1) is 1×10⁻⁶. 7 -10×10 7 per ml.

[0013] Preferably, the microalgae in the microalgae cells described in step (1) include common Chlorella and Chlorella proteoglycans.

[0014] Preferably, the microalgae described in step (3) are inoculated into the wastewater obtained in step (2) at a biomass of 0.1-0.3 g / L.

[0015] Preferably, in step (3), the microalgae that have undergone nitrogen starvation acclimatization are co-cultured with yeast at a mass ratio of 2:1.

[0016] Preferably, in step (3), the pH value of the wastewater is adjusted to 6.0-7.0 daily using hydrochloric acid.

[0017] This invention also protects the application of the method for treating and recycling high ammonia nitrogen wastewater in the treatment of high ammonia nitrogen wastewater.

[0018] Preferably, the ammonia nitrogen concentration in the high ammonia nitrogen wastewater is greater than 300 mg / L, and the total organic carbon is 8000-20000 mg / L.

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

[0020] 1. In the method proposed in this invention, when microalgae undergo nitrogen starvation pretreatment, the daily total nitrogen removal rate of microalgae from zeolite-containing aquaculture wastewater increases to 74.57 mg / L / day, and the treatment cycle is shortened to less than 7 days. Therefore, during microalgal nitrogen fixation, nitrogen starvation can improve the TN removal rate and shorten the total treatment time. Because nitrogen starvation, as an unfavorable condition for microalgal growth, induces the formation of algal dormant vesicles. When algal cells move from a nitrogen-deficient environment to a nitrogen-rich environment, they readily absorb nitrogen. The response of these algal cells to the sudden increase in total nitrogen concentration in the culture medium can be considered as compensatory nitrogen assimilation caused by nutrient mode shift.

[0021] 2. This invention adds zeolite to reduce the initial total ammonia nitrogen (TAN) concentration by adsorbing ammonium ions, thus avoiding the toxic effects of high ammonia nitrogen in aquaculture wastewater on microalgae. Simultaneously, as microalgae grow and consume TAN, the ammonium in the zeolite desorbs, continuously providing a nitrogen source for algal cells, balancing the carbon-to-nitrogen ratio in the aquaculture wastewater to maintain a high microalgae yield. Undiluted wastewater can be directly used for microalgae cultivation, simplifying the wastewater treatment process. The reduced ammonia nitrogen concentration, under daily pH control, also reduces the volatilization of high-concentration ammonia and its serious threat to air quality. Therefore, adding zeolite not only reduces ammonia toxicity but also promotes nitrogen migration and algal growth, increasing nitrogen recovery rate and microalgal protein content. The co-growth of yeast and domesticated microalgae in the aquaculture wastewater also mitigates pH fluctuations, as yeast growth promotes wastewater acidification, while microalgae growth promotes wastewater alkalization. A neutral pH without drastic fluctuations prevents ammonia volatilization and reduces nitrogen loss during wastewater resource recovery. More importantly, the co-culture of yeast and microalgae increases low molecular weight organic matter, which helps to assimilate nitrogen more quickly, improve biomass and nutrient removal rate, and greatly reduce the energy footprint in practical applications.

[0022] 3. The method proposed in this invention is a more environmentally friendly, economical, and applicable method for the resource recovery of aquaculture wastewater. Besides aquaculture wastewater, many other wastewaters rich in ammonia nitrogen, such as food processing wastewater and slaughterhouse wastewater, can also be treated using the method proposed in this invention. Attached image description:

[0023] Figure 1 This is a flowchart of the method for treating and recycling high ammonia nitrogen wastewater proposed in this invention.

[0024] Figure 2This is a diagram illustrating the effect of algal cells growing under nitrogen-deficient acclimatization to remove nutrients in Example 1.

[0025] Figure 3 This is a diagram illustrating the effect of algal cells in Comparative Example 2 growing to remove nutrients without nitrogen deficiency. Detailed implementation method:

[0026] The following embodiments are further illustrations of the present invention, but not limitations thereof.

[0027] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention. Unless otherwise specified, the materials used in the following embodiments are commercially available, and Hunter Trace Elements was purchased from Shanghai Guangyu Biotechnology Co., Ltd.

[0028] like Figure 1 As shown, a method for treating and recycling high-ammonia nitrogen wastewater includes the following steps:

[0029] (1) Microalgae were inoculated in TAP medium without nitrogen source and subjected to nitrogen starvation acclimatization culture for 3-6 days. The culture temperature, light intensity, shaking speed and light-dark cycle were set to 22℃-30℃, 100-200μmol / m·s, 80-150rpm and 12 / 12-16 / 8h, respectively. The TAP medium contained the following components: 20mM tris(hydroxymethyl)aminomethane, 17mM glacial acetic acid, 0.69mM disodium hydrogen phosphate, 0.45mM dipotassium dihydrogen phosphate, 0.4mM magnesium sulfate, 0.35mM calcium chloride, 1mL / L Hunter's trace elements, and the remainder was deionized water. Only 3-6 days of nitrogen starvation acclimatization culture was carried out to avoid the microalgae from decomposing too much intracellular protein and dying.

[0030] (2) Add zeolite to the high ammonia nitrogen wastewater to reduce the TAN concentration of the high ammonia nitrogen wastewater to 200-300 mg / L; microalgae that have undergone nitrogen starvation can improve the nitrogen removal efficiency of aquaculture wastewater with TAN concentration adjusted to 200-300 mg / L by an aeration device to 39.86-77.33 mg / L / day.

[0031] (3) Microalgae and yeast that have undergone nitrogen starvation acclimatization are co-cultured at a mass ratio of 4:1 to 1:1 to treat the wastewater obtained in step (2). At the same time, the pH value of the wastewater is adjusted to 6.0-7.0 every day. After 6-8 days of treatment, the wastewater obtained has a biomass of more than 4 g / L and a removal rate of more than 75% for TOC, TN, TAN and TP compared with the high ammonia nitrogen wastewater to be treated. Among them, the removal rate of TAN can reach more than 95%.

[0032] Preferably, the culture conditions in step (1) are set as follows: temperature, light intensity, shaking speed and light-dark cycle are set to 28±1℃, 150±10μmol / m·s, 100rpm and 16 / 8h, respectively.

[0033] Preferably, in the following embodiments, the concentration of microalgae cells inoculated in the culture medium in step (1) is 1×10⁻⁶. 7 -10×10 7 Cells / mL, the microalgae in the microalgae cells include common Chlorella and proteocyst Chlorella.

[0034] In the following embodiments, it is preferred that the microalgae inoculate the wastewater obtained in step (2) at a biomass of 0.1-0.3 g / L in step (3); the microalgae after nitrogen starvation acclimatization culture are co-cultured with yeast at a mass ratio of 2:1; and the pH of the wastewater is adjusted to 6.0-7.0 daily using hydrochloric acid.

[0035] The water quality parameters of the pig farm wastewater used in the following examples and comparative examples are shown in Table 1.

[0036] Table 1 Water quality parameters of pig farm wastewater

[0037]

[0038] In the following examples, the TAP culture medium preferably comprises the following components: 20 mM tris(hydroxymethyl)aminomethane, 17 mM glacial acetic acid, 0.69 mM disodium hydrogen phosphate, 0.45 mM dipotassium dihydrogen phosphate, 0.4 mM magnesium sulfate, 0.35 mM calcium chloride, 1 mL / L Hunter's trace elements, and the remainder being deionized water.

[0039] Example 1:

[0040] Common Chlorella cells with high protein content (>50%) were selected. Approximately 1.1 × 10⁻⁶ Chlorella cells were inoculated into modified TAP medium without a nitrogen source. 7 The microalgae were cultured at a density of 1 microalgae / mL at a temperature of 28±1℃, a light intensity of 150±10 μmol / m·s, a shaking speed of 100 rpm, and a light / dark cycle of 16 / 8 h for 4 days under nitrogen starvation acclimatization. The nitrogen-starved microalgae were recovered by centrifugation (5000g) and inoculated into 1L of pig farm wastewater containing 125g / L zeolite adsorption for 15 hours at a biomass of 0.2 g / L. At this point, the TAN concentration decreased to approximately 300 mg / L. Simultaneously, yeast was inoculated at a microalgae to yeast mass ratio of 2:1 to form a co-culture system to treat the zeolite-adsorbed pig farm wastewater. The pH of the wastewater was adjusted to 6.0 daily using 1M hydrochloric acid.

[0041] After 7 days of treatment under the above conditions, various water quality indicators and biomass were tested, and the removal rates of COD, TOC, TP, TAN, and TN, as well as biomass, protein content, and nitrogen recovery rate, were calculated. See Table 2 for details.

[0042] Table 2. Processing effect of Example 1

[0043]

[0044] Example 2:

[0045] Similar to Example 1, except that yeast was inoculated at a mass ratio of 4:1 to form a co-culture system to treat the pig wastewater after zeolite adsorption.

[0046] After 7 days of treatment, various water quality indicators and biomass were tested, and the removal rates of COD, TOC, TP, TAN, and TN, as well as biomass, protein content, and nitrogen recovery rate, were calculated. See Table 3 for details.

[0047] Table 3. Treatment effect of Example 2

[0048]

[0049] Example 3:

[0050] Similar to Example 1, except that yeast was inoculated at a mass ratio of 1:1 to form a co-culture system to treat the pig wastewater after zeolite adsorption.

[0051] After 7 days of treatment, various water quality indicators and biomass were tested, and the removal rates of COD, TOC, TP, TAN, and TN, as well as biomass, protein content, and nitrogen recovery rate, were calculated. See Table 4 for details.

[0052] Table 4. Treatment effect of Example 3

[0053]

[0054] Example 4:

[0055] Same as Example 1, except that: microalgae were inoculated in nitrogen-free TAP medium, cultured at a temperature of 22℃±1℃, a light intensity of 100±10 μmol / m·s, a shaking speed of 80 rpm, and a light / dark cycle of 12 / 12 h; the concentration of microalgae cells in the inoculated medium was 1×10⁻⁶. 7 Microalgae were inoculated at a biomass of 0.1 g / L into the wastewater obtained in step (2) for 4 days of nitrogen starvation acclimatization culture. Zeolite was added to the high ammonia nitrogen wastewater to be treated to reduce the TAN concentration of the high ammonia nitrogen wastewater to 200 mg / L. Microalgae were inoculated into the wastewater obtained in step (2) at a biomass of 0.1 g / L. The pH of the wastewater was adjusted to 6.0 with hydrochloric acid every day for 6 days.

[0056] After treatment under the above conditions for 6 days, various water quality indicators and biomass were tested, and the removal rates of COD, TOC, TP, TAN, and TN, as well as biomass, protein content, and nitrogen recovery rate, were calculated. See Table 5 for details.

[0057] Table 5. Processing effect of Example 4

[0058]

[0059] Example 5:

[0060] Same as Example 1, except that: microalgae were inoculated in nitrogen-free TAP medium, cultured at a temperature of 30℃±1℃, a light intensity of 200±10 μmol / m·s, a shaking speed of 150 rpm, and a light / dark cycle of 16 / 8 h; the concentration of microalgae cells in the inoculated medium was 10×10⁻⁶. 7 Microalgae were inoculated at a biomass of 0.3 g / L into the wastewater obtained in step (2) for 6 days of nitrogen starvation acclimatization culture. Zeolite was added to the high ammonia nitrogen wastewater to be treated to reduce the TAN concentration of the high ammonia nitrogen wastewater to 300 mg / L. Microalgae were inoculated into the wastewater obtained in step (2) at a biomass of 0.3 g / L. The pH of the wastewater was adjusted to 7.0 with hydrochloric acid every day for 8 days.

[0061] After 8 days of treatment under the above conditions, various water quality indicators and biomass were tested, and the removal rates of COD, TOC, TP, TAN, and TN, as well as biomass, protein content, and nitrogen recovery rate, were calculated. See Table 6 for details.

[0062] Table 6. Processing effect of Example 5

[0063]

[0064]

[0065] Comparative Example 1:

[0066] The difference from Example 1 is that fresh water dilution and ammonia stripping are used instead of the new treatment process of this invention.

[0067] Specifically, a method for treating aquaculture wastewater includes the following steps: Based on preliminary experiments, 1L of pig farm wastewater is diluted by mixing it with 2L of fresh water. Ammonia stripping is performed by reducing the TAN concentration in 1L of pig farm wastewater to approximately 300mg / L using an aeration device. After pretreatment, microalgae are inoculated at an initial density of only 0.2g / L. Except for the absence of nitrogen starvation and pH control, the culture conditions and pig farm wastewater used in this comparison are the same as in Example 1.

[0068] After treating the wastewater under the above conditions for 7 days, the nitrogen index was measured, and the nitrogen fate during the treatment process was calculated. See Table 7 for details.

[0069] Table 7 Nitrogen fate under different treatment methods

[0070]

[0071] Comparing Example 1 and Comparative Example 1, it is evident that when using traditional freshwater dilution and ammonia stripping to reduce the adverse effects of high ammonia nitrogen on microalgae, in addition to failing to achieve the higher biomass, nitrogen utilization rate, and protein content of this invention, it also results in the loss of freshwater and nitrogen resources and air pollution. Therefore, high freshwater consumption hinders its application in arid or semi-arid regions. The low nutrient concentration resulting from dilution also severely reduces the yield of microalgae biomass. In practical applications, high concentrations of ammonia volatilization also pose a serious threat to air quality; therefore, it cannot be considered an eco-friendly method for the resource-based treatment of pig farm wastewater.

[0072] Comparative Example 2:

[0073] The difference from Example 1 is that the treatment effect of nitrogen starvation on aquaculture wastewater with and without nitrogen starvation is compared.

[0074] Common Chlorella, containing a high protein content (50%), was selected. Approximately 1.1 × 10⁶ algal cells were inoculated into TAP medium containing a nitrogen source. 7 The microalgae were cultured at a density of 1 / mL at a temperature of 28±1℃, a light intensity of 150±10 μmol / m·s, a shaking speed of 100 rpm, and a light / dark cycle of 16 / 8 h for a 4-day nitrogen starvation period. The nitrogen-containing ATP culture medium consisted of: 20 mM tris(hydroxymethyl)aminomethane, 17 mM glacial acetic acid, 0.69 mM disodium hydrogen phosphate, 0.45 mM dipotassium dihydrogen phosphate, 7.5 mM ammonium chloride, 0.4 mM magnesium sulfate, 0.35 mM calcium chloride, 1 mL / L Hunter trace element, and the remainder deionized water. Microalgae that had undergone nitrogen starvation were recovered by centrifugation at 5000 g and inoculated at a biomass of 0.2 g / L into 1 L of pig farm wastewater that had been treated with 125 g / L zeolite for 15 hours. At this point, the TAN concentration had decreased to approximately 300 mg / L. Simultaneously, the pH of the wastewater was adjusted to 6.0 daily using 1 M hydrochloric acid. Except for the absence of nitrogen starvation, the culture conditions and pig wastewater used in this comparison were the same as in Example 1.

[0075] Monitor various water quality indicators and biomass to obtain the number of days required to treat aquaculture wastewater under the above conditions. The parameters include TOC, total phosphorus, ammonia nitrogen, total nitrogen, and biomass. Figure 2 and 3 As shown. Comparison Figure 2 and 3 It can be found that nitrogen starvation treatment of microalgae can reduce the treatment time from 12 days to 7 days while ensuring satisfactory treatment results and biomass.

[0076] Comparative Example 3:

[0077] Similar to Example 1, except that: only 5000g of microalgae that had been acclimatized to nitrogen starvation were centrifuged and recovered, and inoculated into 1L of pig farm wastewater that had been adsorbed with 125g / L zeolite for 15 hours with a biomass of 0.3g / L. At this time, the TAN concentration dropped to about 300mg / L, and the pH of the wastewater was adjusted to 6.0 with 1M hydrochloric acid every day.

[0078] After 7 days of treatment under the above conditions, various water quality indicators and biomass were tested, and the removal rates of COD, TOC, TP, TAN, and TN, as well as biomass, protein content, and nitrogen recovery rate, were calculated. See Table 8 for details.

[0079] Table 8 shows the treatment effect of Comparative Example 3.

[0080]

[0081] Comparative Example 4:

[0082] Similar to Example 1, except that: yeast was inoculated into 1L of pig farm wastewater with a biomass of 0.3 g / L and zeolite adsorption of 125 g / L for 15 hours. At this time, the TAN concentration dropped to about 300 mg / L. The pH of the wastewater was adjusted to 6.0 with 1M hydrochloric acid every day.

[0083] After 7 days of treatment under the above conditions, various water quality indicators and biomass were tested, and the removal rates of COD, TOC, TP, TAN, and TN, as well as biomass, protein content, and nitrogen recovery rate, were calculated. See Table 9 for details.

[0084] Table 9 shows the treatment effects in Comparative Example 4.

[0085]

[0086] The above description of the embodiments is only for the purpose of helping to understand the technical solution and core idea of ​​the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for treating and recycling high-ammonia nitrogen wastewater, characterized in that, Includes the following steps: (1) Microalgae were inoculated in nitrogen-free TAP medium and subjected to nitrogen starvation acclimatization culture for 3-6 days to prevent excessive decomposition of intracellular proteins and death of the microalgae. The culture temperature, light intensity, shaking speed and light-dark cycle were set at 22℃-30℃ and 100-200 μmol / (m²) respectively. 2 •s), 80-150 rpm and 12 / 12-16 / 8 h; (2) Add zeolite to the high ammonia nitrogen wastewater to reduce the TAN concentration of the high ammonia nitrogen wastewater to 200-300 mg / L, wherein the ammonia nitrogen concentration in the high ammonia nitrogen wastewater is greater than 300 mg / L and the total organic carbon is 8000-20000 mg / L; (3) The microalgae that have undergone nitrogen starvation acclimatization culture are co-cultured with yeast at a mass ratio of 2:1 to treat the wastewater obtained in step (2). The microalgae are inoculated into the wastewater obtained in step (2) at a biomass of 0.1-0.3 g / L. At the same time, the pH value of the wastewater is adjusted to 6.0-7.0 every day. After 6-8 days of treatment, the wastewater obtained has a TAN removal rate of more than 95% compared with the high ammonia nitrogen wastewater to be treated.

2. The method according to claim 1, characterized in that, Step (1) The concentration of microalgae cells inoculated in the culture medium is 1×10⁻⁶. 7 -10×10 7 per ml.

3. The method according to claim 1, characterized in that, The microalgae mentioned in step (1) include common Chlorella and Chlorella proteoglycans.

4. The method according to claim 1, characterized in that, In step (3), the pH value of the wastewater is adjusted to 6.0-7.0 daily using hydrochloric acid.

5. The application of the method for treating and recycling high ammonia nitrogen wastewater according to claim 1 in the treatment of high ammonia nitrogen wastewater.

6. The application according to claim 5, characterized in that, The ammonia nitrogen concentration in the high ammonia nitrogen wastewater is greater than 300 mg / L, and the total organic carbon is 8000-20000 mg / L.

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