An apparatus and method for recovering nitrous oxide from high ammonia nitrogen wastewater using algae-bacteria symbiosis technology.

Abstract

This invention provides an apparatus and method for recovering nitrous oxide from high-ammonia-nitrogen wastewater using algae-bacteria symbiotic technology. The apparatus includes an aerobic reaction unit and an anoxic reaction unit; the first outlet of the aerobic reaction unit and the inlet of the anoxic reaction unit are connected, and a monovalent anion exchange membrane is installed at the connection point; the aerobic reaction unit is connected to a first gas collection unit via a first gas outlet, and the anoxic reaction unit is connected to a second gas collection unit via a second gas outlet, for recovering nitrous oxide generated in both the aerobic and anoxic reaction units. This invention, by inoculating the aerobic reaction unit with algae-bacteria symbiotic sludge that achieves short-cut nitrification, effectively reduces the aeration energy consumption of short-cut nitrification through microalgae photosynthesis, realizes the recovery of nitrous oxide in the aerobic reaction unit, reduces the denitrification load in the anoxic reaction unit, increases the denitrification conversion rate, and reduces operating costs, embodying a high-efficiency, low-carbon, and environmentally friendly design concept.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to an apparatus and method for recovering nitrous oxide from high ammonia nitrogen wastewater using algae-bacteria symbiosis technology. Background Technology

[0002] Nitrous oxide (N2O) is an energy gas with high energy value and can be used as a combustion aid or rocket oxidizer. Currently, in the field of wastewater treatment, N2O has always been an undesirable greenhouse gas released during wastewater denitrification. Reducing its emissions has always been the mainstream of this research field. However, some studies are dedicated to recovering N2O from high ammonia nitrogen wastewater.

[0003] There are three main pathways for N2O generation in biological denitrification of wastewater: First, in the aerobic short-cut nitrification process, hydroxylamine undergoes incomplete oxidation to generate nitryl groups, which then generate N2O through enzymatic catalysis or chemical degradation. Second, ammonia-oxidizing bacteria (AOB), which dominate short-cut nitrification, carry out denitrification under the stimulation of low dissolved oxygen and high nitrite concentrations. Since AOB lacks the nosZ gene, the denitrification product is N2O. Third, N2O is generated in the anoxic denitrification process when Nos enzyme activity is inhibited or electron donors are insufficient.

[0004] Currently, existing technologies mainly achieve efficient N2O conversion by regulating the denitrification process in the anoxic stage. However, based on the known principles of N2O production, the aerobic stage can also produce N2O. Since this stage typically provides dissolved oxygen to the activated sludge through aeration, it is not conducive to recovery. Furthermore, the N2O produced by activated sludge in the aerobic stage is generally only between 0.5% and 3%, resulting in a very low recovery cost-effectiveness. Therefore, in most biological nitrogen removal and N2O recovery methods, the aerobic stage is only used as a pretreatment process for the anoxic stage. Therefore, how to simultaneously achieve low aeration and high N2O conversion in the aerobic stage, thereby achieving efficient N2O recovery while also achieving energy conservation and emission reduction, is one of the hot research topics in this field. Summary of the Invention

[0005] This invention provides an apparatus and method for recovering nitrous oxide from high ammonia nitrogen wastewater using algae-bacteria symbiosis technology, which can achieve efficient N2O recovery while also achieving energy conservation and emission reduction.

[0006] In a first aspect, the present invention provides an apparatus for recovering nitrous oxide from high ammonia nitrogen wastewater, comprising an aerobic reaction unit, an anoxic reaction unit, a first gas collection unit, and a second gas collection unit;

[0007] The aerobic reaction unit includes a first inlet, a first outlet, a second outlet, and a first gas outlet. The first inlet is used to input high ammonia nitrogen wastewater to be treated. The first outlet is connected to the second inlet of the anoxic reaction unit, and a monovalent anion exchange membrane is provided at the connection. The first gas outlet is connected to a first gas collection unit, which is used to recover nitrous oxide generated by the aerobic reaction unit. The second outlet is used to output the wastewater treated by the aerobic reaction unit. The aerobic reaction unit is inoculated with activated sludge containing bacteria and algae, including ammonia-oxidizing bacteria, denitrifying bacteria, and common Chlorella. Chlorella vulgaris The common Chlorella Chlorella vulgaris Its number in the Freshwater Algae Culture Bank of the Chinese Academy of Sciences is FACHB-2338; The anoxic reaction unit includes a second water inlet, a second gas outlet, a third water outlet, and a feed inlet. The second gas outlet is connected to a second gas collection unit, which is used to recover nitrous oxide generated by the anoxic reaction unit. The feed inlet is used to replenish carbon sources into the anoxic reaction unit. The third water outlet is used to discharge wastewater treated by the anoxic reaction unit. The hypoxia reaction unit was inoculated with nosZ Denitrifying engineered bacteria with missing genes.

[0008] The apparatus described above, wherein the ammonia nitrogen (NH4) in the high ammonia nitrogen wastewater to be treated + The concentration of (-N) was 400±20 mg / L, and the pH was 8.5±0.2.

[0009] In the device described above, the aerobic reaction unit and the anoxic reaction unit can have the same volume, that is, the ratio of the internal volume of the aerobic reaction unit to the anoxic reaction unit is 1:1; specifically, the volume of both the aerobic reaction unit and the anoxic reaction unit is 1L.

[0010] As described above, in the device described, the ammonia-oxidizing bacteria (AOB) in the algae-activated sludge reduce ammonia nitrogen (NH4) in the wastewater. + ) is oxidized to nitrite (NO2) - ), while nitrite (NO2) - Because nitrite-oxidizing bacteria (NOB) are inhibited, they cannot further oxidize to nitrate (NO3). - This process mainly enhances the activity of ammonia-oxidizing bacteria (AOB) and effectively inhibits the activity of nitrite-oxidizing bacteria (NOB) in sludge through environmental factors such as light and dissolved oxygen.

[0011] In the device described above, the denitrifying bacteria include aerobic denitrifying bacteria and incomplete denitrifying bacteria, which are mainly used to produce nitrous oxide.

[0012] In the device described above, the activated sludge is derived from activated sludge from a low-dissolved-oxygen aerobic tank and common Chlorella vulgaris. Chlorella vulgaris The mixture is prepared by mixing in a 5:1 mass ratio and then undergoing an acclimatization process. The acclimatization process includes inoculating the activated sludge with a certain concentration of ammonia nitrogen in wastewater. After the activated sludge adapts to the concentration, the concentration of ammonia nitrogen in the wastewater is increased until the activated sludge can accept the target concentration of ammonia nitrogen in the wastewater, thus obtaining the acclimatized activated sludge.

[0013] In the apparatus described above, the concentration of the activated sludge in the aerobic reaction unit is 6000±500 mg / L.

[0014] The device as described above, the nosZ Gene-deleted denitrifying engineered bacteria are specifically... nosZ Gene deletion P.aeruginosa PAO1 requires sodium acetate as its carbon source.

[0015] The device described above further includes a temperature control unit for controlling the temperature within the aerobic reaction unit and the anoxic reaction unit.

[0016] The device described above further includes a supplementary lighting unit for providing illumination to the activated sludge.

[0017] The apparatus as described above further includes a dissolved oxygen and pH monitoring unit, which is used to detect the dissolved oxygen concentration and pH within the aerobic reaction unit.

[0018] The apparatus as described above further includes an aeration unit for supplying oxygen to the aerobic reaction unit.

[0019] The apparatus as described above further includes a stirring unit located within the aerobic reaction unit and the anoxic reaction unit.

[0020] In a second aspect, the present invention provides a method for recovering nitrous oxide from high ammonia nitrogen wastewater, using any of the apparatus described above, comprising: The high ammonia nitrogen wastewater to be treated is fed into the aerobic reaction unit through the first inlet. The ammonia nitrogen in the wastewater is converted into nitrite nitrogen and nitrous oxide by the activated sludge of bacteria and algae inoculated in the aerobic reaction unit. The generated nitrous oxide is output to the first gas collection unit through the first gas outlet. The treated wastewater is output from the first outlet and the second outlet. Wastewater discharged from the first outlet is fed into the anoxic reaction unit through the monovalent anion exchange membrane, and then inoculated within the anoxic reaction unit... nosZGene-deleted denitrifying engineered bacteria convert nitrite nitrogen in wastewater into nitrous oxide. The generated nitrous oxide is output to the second gas collection unit through the second gas outlet, and the treated wastewater is output from the third outlet. nosZ The carbon source required by the gene-deleted denitrifying engineered bacteria is fed into the anoxic reaction unit through the feed inlet.

[0021] As described above, the light intensity in the aerobic reaction unit is 8000 Lux, and the light-dark cycle is 10h:14h.

[0022] As described above, the dissolved oxygen concentration in the aerobic reaction unit is 0.2-0.5 mg / L, and the pH is 8.0 ± 0.2.

[0023] As described above, the temperature within the aerobic reaction unit and the hypoxic reaction unit is 30℃±1℃.

[0024] As described above, the short-range nitrification reaction cycle in the aerobic reaction unit is 24 hours, and the denitrification reaction cycle in the anoxic reaction unit is 24 hours.

[0025] This invention, by inoculating an aerobic reaction unit with activated sludge containing common Chlorella, effectively reduces the aeration energy consumption for short-cut nitrification through microalgae photosynthesis, achieving N2O recovery in the aerobic stage. Furthermore, the N2O conversion in the aerobic stage requires no carbon source addition, and this conversion rate consumes up to 30% of the total nitrogen, significantly reducing the denitrification load in the anoxic stage, decreasing the amount of carbon source required, and further lowering operating costs, embodying the low-carbon and environmentally friendly concept of this invention. In this invention, the denitrification and N2O production processes in the aerobic and anoxic stages are almost simultaneous, greatly improving the denitrification conversion rate and reducing the reaction time. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the device provided by the present invention for recovering nitrous oxide from high ammonia nitrogen wastewater; Figure 2 The composition and distribution of nitrogen in the aerobic reaction unit in Example 2 and Comparative Example 1; Figure 3 The abundance statistics of each functional bacteria in Example 2 and Comparative Example 3 are shown.

[0027] Explanation of reference numerals in the attached figures: 1-First water inlet; 2-First gas outlet; 3-Second water outlet; 4-Aeration unit; 5-Aeration pump; 6-Third water outlet; 7-Second gas outlet; 8-Second gas collection unit; 9-First gas collection unit; 10-Second stirring unit; 11-First stirring unit; 12-First temperature control unit; 13-Second temperature control unit; 14-Aerobic reaction unit; 15-Anoxic reaction unit; 16-Monovalent anion exchange membrane; 17-Dissolved oxygen and pH monitoring unit; 18-Feeding port; 19-Supplemental lighting unit. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, embodiments of this invention, and should not be construed as limiting the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. In the description of this invention, it should be understood that the terminology used is for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0030] Example 1: Apparatus for recovering nitrous oxide from high ammonia nitrogen wastewater like Figure 1 As shown, the device includes an aerobic reaction unit 14 and an anoxic reaction unit 15, which are arranged sequentially along the flow direction of the wastewater to be treated.

[0031] The aerobic reaction unit 14 is equipped with a first inlet 1, a first outlet 3, a second outlet 3, and a first gas outlet 2. The first inlet 1 is located at the top of the aerobic reaction unit and is used to input the high ammonia nitrogen wastewater to be treated into the aerobic reaction unit 14. The first outlet is connected to the anoxic reaction unit 15 through a connecting pipe, and a monovalent anion exchange membrane 16 is installed in the middle of the connecting pipe to remove NO2 generated in the aerobic reaction unit 14. -The wastewater diffuses freely into the anoxic reaction unit 15; the second outlet 3 is located in the middle of the aerobic reaction unit 14 and is used to output the treated wastewater; the first gas outlet 2 is connected to the first gas collection unit 9, which is used to recover the nitrous oxide generated by the aerobic reaction unit 14. In addition, the device also includes a first stirring unit 11, an aeration unit 4, a first temperature control unit 12, a dissolved oxygen and pH monitoring unit 17, and a supplementary lighting unit 19. The first stirring unit 11 is located inside the aerobic reaction unit 14 and is used to ensure the uniform distribution of substances such as bacterial and algal activated sludge and dissolved oxygen within the aerobic reaction unit 14. The aeration unit 4 is located at the bottom of the aerobic reaction unit 14 and is used to supply oxygen to the interior of the aerobic reaction unit 14. The aeration unit 4 is also connected to an aeration pump 5. The first temperature control unit 12 is connected to the aerobic reaction unit 14 via a temperature sensor and is used to control the temperature within the aerobic reaction unit 14. The dissolved oxygen and pH monitoring unit 17 is connected to the aerobic reaction unit 14 via a sensor and is used to monitor the dissolved oxygen concentration and pH value within the aerobic reaction unit 14. The supplementary lighting unit is used to provide light for the bacterial and algal activated sludge.

[0032] The aerobic reaction unit 14 is inoculated with activated sludge containing bacteria and algae, including common Chlorella vulgaris. Chlorella vulgaris The common Chlorella Chlorella vulgaris The activated sludge, designated FACHB-2338 in the Chinese Academy of Sciences Freshwater Algae Culture Bank, originated from a low-dissolved-oxygen aerobic tank in a pig farm's wastewater treatment facility. The functional microbial community it contained included ammonia-oxidizing bacteria and denitrifying bacteria. The activated sludge and common Chlorella were mixed at a mass ratio of 5:1, and the mixture was acclimatized to obtain the bacterial-algae activated sludge. The acclimation method specifically includes: mixing activated sludge and common Chlorella to obtain a bacterial-algae sludge mixture; setting an influent concentration gradient based on the ammonia nitrogen concentration of the wastewater to be treated; starting from the lowest concentration, several cycles are set for each concentration of wastewater according to the effluent conditions, with each cycle set to 24 hours, including a 10-minute influent stage, a 22-hour aeration stage, a 1-hour sedimentation stage, a 20-minute effluent stage, and a 30-minute idle stage; once the bacterial-algae sludge mixture adapts to the influent ammonia nitrogen concentration, the ammonia nitrogen concentration in the wastewater is increased, and the acclimation to the next concentration gradient is initiated until the bacterial-algae sludge mixture can adapt to the target wastewater, resulting in well-acclimated bacterial-algae activated sludge. The acclimated bacterial-algae activated sludge can effectively convert ammonia nitrogen in the wastewater into nitrite nitrogen and stably produce nitrous oxide. When the wastewater to be treated enters the aerobic reaction unit 14, it is converted into nitrite and N2O through the combined action of activated sludge and common Chlorella. N2O is collected in the first gas collection unit 9 through the first gas outlet 2, while nitrite enters the anoxic reaction unit 15 through the anion exchange membrane.

[0033] The anoxic reaction unit 15 is equipped with a second water inlet, a second gas outlet 7, a third water outlet 6, and a feed inlet 18. The second water inlet is connected to the aerobic reaction unit 14 via a connecting pipe. The second gas outlet 7 is connected to the second gas collection unit 8, which is used to recover nitrous oxide generated by the anoxic reaction unit. The feed inlet 18 is used to supplement the anoxic reaction unit with carbon source. The third water outlet 6 is located in the middle of the anoxic reaction unit 15 and is used to discharge wastewater of the same volume as the added carbon source.

[0034] The device also includes a second temperature control unit 13 and a second stirring unit 10; the second stirring unit 10 is located inside the anoxic reaction unit 15 and is used to ensure that denitrifying bacteria and other substances are evenly distributed in the anoxic reaction unit 15; the second temperature control unit 13 is connected to the anoxic reaction unit 15 through a temperature sensor and is used to control the temperature inside the anoxic reaction unit 15.

[0035] The hypoxia reaction unit was inoculated with nosZ Gene deletion P.aeruginosa PAO1 denitrifying strain. When NO2 is present... - After the wastewater enters the anoxic reaction unit 15, it undergoes... nosZ The gene-knockout denitrifying engineered bacteria convert it into N2O, which is then collected in the second gas collection unit 8 via the second gas output. nosZ Gene deletion P.aeruginosa The PAO1 denitrifying strain is described in the literature: Lin, Z., Sun, D., Dang, Y., Holmes, DE, 2018. Significant enhancement of nitrous oxide energy yields from wastewater achieved by bioaugmentation with a recombinants train of Pseudomonas aeruginosa. Sci. Rep.8 (1), 11916.

[0036] The high-ammonia nitrogen wastewater to be treated enters the aerobic reaction unit 14 through the first inlet 1. The retention time is set to 24 hours. The aeration unit 4 and the dissolved oxygen and pH monitoring unit 17 are used to provide oxygen to the aerobic reaction unit 14 and control the dissolved oxygen concentration at 0.2-0.5 mg / L and the pH at 8.0±0.2. The stirring speed of the first stirring unit 11 is controlled at 200 r / min to ensure that the activated sludge of bacteria and algae in the aerobic reaction unit 14 is fully contacted and evenly distributed with the wastewater and dissolved oxygen. The first temperature control unit 12 is used to control the temperature in the aerobic reaction unit 14 at 30±1℃. The above control parameters are the optimal conditions for short-cut nitrification by nitrifying bacteria (AOB). Nitrifying bacteria (NOB) are inhibited in this environment, so ammonia nitrogen is converted into NO2. - This facilitates subsequent reactions; within the aerobic reaction unit, a portion of the nitrite nitrogen is converted into N2O under the aerobic denitrification of the bacterial and algal sludge, and enters the first gas collection unit 9 through the first gas outlet 2 of the aerobic reaction unit 14 to complete N2O recovery; the other portion of NO2 - The nitrogen ions pass through the monovalent anion exchange membrane 16 into the anoxic reaction unit 15, where a large number of denitrifying engineered bacteria are enriched, capable of converting NO2 into nitrogen. - The N2O is converted into N2O and enters the second gas collection unit 8 through the second gas outlet 7 of the anoxic reaction unit 15 to complete N2O recovery. Sodium acetate is continuously added through the feed inlet 18 to supplement the carbon source required for denitrification. After the reaction is completed, a bacterial solution of the same volume as the added carbon source is discharged through the third outlet 6 of the anoxic reaction unit 15 to maintain the system balance.

[0037] Example 2: The anaerobic effluent from a pig farm wastewater treatment project was treated using the apparatus provided in Example 1. Taking the anaerobic effluent from a pig farm wastewater treatment project as an example, the influent water quality is: COD concentration 500 mg / L, BOD5 concentration 250 mg / L, NH4+ concentration... + The -N concentration is 400 mg / L, and the pH is approximately 8.5. The total volume of the aerobic reaction unit 14 and the anoxic reaction unit is 2 L, with each unit containing 1 L. The aerobic reaction unit 14 is inoculated with acclimated algal-based activated sludge at a concentration of 6000 mg / L and an age of 30 days. The aeration rate in the aerobic tank is 25 ml / min, dissolved oxygen is 0.2-0.5 mg / L, pH is 8.0 ± 0.2, light intensity is 8000 Lux, and the light-dark cycle is 10 h:14 h. The anoxic tank is inoculated with... nosZ For denitrifying bacteria with gene deletion, the temperature of both the aerobic and anoxic reaction units was controlled at 30℃.

[0038] Wastewater to be treated, filling 50% of its effective volume, is introduced into the aerobic reaction unit 14, followed by aeration and stirring. Simultaneous stirring is also carried out in the anoxic tank. The influent stage lasts for 10 minutes. After running for 11 hours, an appropriate amount of carbon source and trace elements are added to the anoxic reaction unit 15. The running stage lasts for 22 hours. The sedimentation time is 1 hour. The effluent volume of the aerobic reaction unit is 50% of the total wastewater volume in the aerobic reaction unit, and the effluent volume of the anoxic reaction unit is equal to the volume of added carbon source. The effluent stage lasts for 20 minutes. The idle stage lasts for 0.5 hours.

[0039] After the device is running stably, the NH4 content in the aerobic and anoxic reaction units is measured. + -N, NO2 - The concentrations of -N and N2O were detected in the aerobic reaction unit. + -N is converted to NO2 - -N conversion rate reaches over 95%, of which 30% is NO2. - -N is converted into N2O by the aerobic reaction unit, with 65% of NO2 being converted into N2O. - -N enters the anoxic reaction unit through the monovalent anion exchange membrane; this portion of NO2 - The conversion rate of -N to N2O reaches 99%, achieving a high conversion rate of N2O while ensuring a high denitrification rate.

[0040] Comparative Example 1 The same wastewater as in Example 2 was treated using a similar method, the only difference being that the activated sludge in Comparative Example 1 was not inoculated with any microalgae.

[0041] Comparative Example 2 The same wastewater as in Example 2 was treated using a similar method, except that in Comparative Example 2, the activated sludge was not inoculated with any microalgae, and the aeration rate of the aerobic reaction unit was increased every 3-5 cycles until the denitrification efficiency was equal to that in Example 2.

[0042] Comparative Example 3 Inoculate activated sludge from the same source that was not inoculated with microalgae with *Mammillaria*. Micractinium pusillum Microscopic algae Micractinium pusillum The sample was deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 46280. After being acclimatized under the same conditions, it was inoculated into an aerobic reaction unit. All other experimental parameters were the same as in Example 2.

[0043] Regarding N2O and NO2 in the aerobic reaction units of Example 2 and Comparative Example 1 - NO3 - The concentrations of nitrogen and other forms were measured, and the results are visible. Figure 2 ,according to Figure 2It can be seen that the ammonia nitrogen removal rate of the uninoculated microalgae activated sludge (AS) under the same aeration rate is only 70% of that of the bacterial-algae activated sludge (AS-Cv), and the nitrous oxide conversion rate is 26% of that of the bacterial-algae group.

[0044] Comparing Example 2 with Comparative Example 2, it was found that the ammonia nitrogen removal rate was similar to that of Example 2 only when the aeration rate in the aerobic reaction unit was increased by 50%.

[0045] Comparing Example 2 and Comparative Example 3, it can be seen that the N2O conversion rate of the bacterial-algal sludge inoculated with Chlorella is 15% higher than that of the bacterial-algal sludge inoculated with Micrococcus; the abundance of related functional bacteria is as follows: Figure 3 AS-Cv(1,2,3) represents activated sludge inoculated with Chlorella vulgaris, and AS-Mp(1,2,3) represents activated sludge inoculated with Micrococcus microcarpa. The results suggest that nitrous oxide production may occur through aerobic denitrification. Nitrosomonas_sp., Nitrosomonas_europaea The proportion of certain bacteria in AS-Cv reaches about 4%, which is 4 times that in AS-Mp; this may lead to the production of nitrous oxide through incomplete denitrification. Thauera_ sp., Thauera_aminoaromatica, Pseudoxanthomonas_sp. The proportion of bacteria in AS-Cv reached 50%, while that in AS-Mp was 43%.

[0046] The experimental data above demonstrate that the algae-bacterial symbiosis technology used in this invention can effectively reduce aeration energy consumption in aerobic tanks, increase nitrous oxide conversion rate, reduce denitrification load in anoxic tanks, and reduce carbon source addition. It possesses the advantages of high-efficiency denitrification, high N2O conversion rate, and low carbon and energy consumption.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An apparatus for recovering nitrous oxide from high-ammonia-nitrogen wastewater, characterized in that, It includes an aerobic reaction unit, an anoxic reaction unit, a first gas collection unit, and a second gas collection unit; The aerobic reaction unit includes a first inlet, a first outlet, a second outlet, and a first gas outlet. The first inlet is used to input high ammonia nitrogen wastewater to be treated. The first outlet is connected to the second inlet of the anoxic reaction unit, and a monovalent anion exchange membrane is provided at the connection. The first gas outlet is connected to a first gas collection unit, which is used to recover nitrous oxide generated by the aerobic reaction unit. The second outlet is used to output the wastewater treated by the aerobic reaction unit. The aerobic reaction unit is inoculated with activated sludge containing bacteria and algae, including ammonia-oxidizing bacteria, denitrifying bacteria, and common Chlorella. Chlorella vulgaris The common Chlorella Chlorella vulgaris Its number in the Freshwater Algae Culture Bank of the Chinese Academy of Sciences is FACHB-2338; The anoxic reaction unit includes a second water inlet, a second gas outlet, a third water outlet, and a feed inlet. The second gas outlet is connected to a second gas collection unit, which is used to recover nitrous oxide generated by the anoxic reaction unit. The feed inlet is used to replenish carbon sources into the anoxic reaction unit. The third water outlet is used to discharge wastewater treated by the anoxic reaction unit. The hypoxia reaction unit was inoculated with nosZ Denitrifying engineered bacteria with missing genes.

2. The apparatus according to claim 1, characterized in that, The algae-bacterial activated sludge is made by mixing activated sludge with common Chlorella. Chlorella vulgaris The mixture was obtained after domestication treatment; In the mixture, the activated sludge and common Chlorella Chlorella vulgaris The mass ratio is 5:

1.

3. The apparatus according to claim 1 or 2, characterized in that, The device also includes a temperature control unit, which is used to control the temperature within the aerobic reaction unit and the hypoxic reaction unit.

4. The apparatus according to claim 1 or 2, characterized in that, The device also includes a supplementary lighting unit, which is used to provide light to the activated sludge.

5. The apparatus according to claim 1 or 2, characterized in that, The device also includes a dissolved oxygen and pH monitoring unit, which is used to detect the dissolved oxygen concentration and pH within the aerobic reaction unit.

6. The apparatus according to claim 1 or 2, characterized in that, The device also includes an aeration unit for supplying oxygen to the aerobic reaction unit.

7. The apparatus according to claim 1 or 2, characterized in that, The device also includes a stirring unit, which is located within the aerobic reaction unit and the anoxic reaction unit.

8. A method for recovering nitrous oxide from high-ammonia-nitrogen wastewater, characterized in that, Using the apparatus according to any one of claims 1-7, comprising: The high ammonia nitrogen wastewater to be treated is fed into the aerobic reaction unit through the first inlet. The ammonia nitrogen in the wastewater is converted into nitrite nitrogen and nitrous oxide by the activated sludge of bacteria and algae inoculated in the aerobic reaction unit. The generated nitrous oxide is output to the first gas collection unit through the first gas outlet. The treated wastewater is output from the first outlet and the second outlet. Wastewater discharged from the first outlet is fed into the anoxic reaction unit through the monovalent anion exchange membrane, and then inoculated within the anoxic reaction unit... nosZ Gene-deleted denitrifying engineered bacteria convert nitrite nitrogen in wastewater into nitrous oxide. The generated nitrous oxide is output to the second gas collection unit through the second gas outlet, and the treated wastewater is output from the third outlet. nosZ The carbon source required by the gene-deleted denitrifying engineered bacteria is fed into the anoxic reaction unit through the feed inlet.

9. The method according to claim 8, characterized in that, The aerobic reaction unit has a light intensity of 8000 Lux, a light-dark cycle of 10h:14h, a dissolved oxygen concentration of 0.2-0.5 mg / L, and a pH of 8.0±0.

2. And / or, the short-range nitrification reaction cycle in the aerobic reaction unit is 24 hours, and the denitrification reaction cycle in the anoxic reaction unit is 24 hours.

10. The method according to claim 8, characterized in that, The temperature inside the aerobic reaction unit and the hypoxic reaction unit is 30℃±1℃.

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