Process for removing pollutants from the effluent of the factory farming of penaeus vannamei

Abstract

The application discloses a process for removing pollutants in factory breeding tail water of penaeus vannamei, and belongs to the technical field of breeding tail water treatment. The process comprises the following steps: (1) filtering breeding wastewater to remove solid matters; (2) adding composite bacteria to the filtered breeding wastewater for aeration treatment to obtain aeration wastewater, wherein the composite bacteria comprise, by weight, 1-2 parts of rhodococcus, 2-3 parts of bacillus subtilis, 3-4 parts of halococcus and 0.8-1.5 parts of photosynthetic bacteria; (3) adding a flocculating agent to the aeration wastewater, treating the aeration wastewater at 45-50 DEG C for 0.5-1 h, and filtering to obtain a first filtrate; (4) adding modified activated carbon to the first filtrate, treating the first filtrate at 45-50 DEG C for 1-2 h, filtering to obtain a second filtrate; and (5) flowing and mixing the second filtrate through a macroporous adsorption resin to obtain a third filtrate, and sterilizing the third filtrate. The application realizes efficient removal of pollutants in the breeding tail water of penaeus vannamei through the combination of physical, chemical and biological treatments.

Description

TECHNICAL FIELD

[0001] The application relates to a process for removing pollutants in factory breeding tail water of Penaeus vannamei, and belongs to the technical field of breeding tail water treatment. BACKGROUND

[0002] The pollutants in the factory breeding tail water of Penaeus vannamei mainly come from the residual bait, shrimp excrement, biological metabolites and breeding water regulating additives (such as disinfectants, water quality improvers and the like) in the breeding process, and may also contain trace pollutants such as antibiotics and heavy metals, which have biological accumulation and ecological risk.

[0003] At present, the tail water treatment technology of shrimp factory breeding has formed three systems of physical, chemical and biological treatment. Among them, the physical treatment includes physical means such as filtration, sedimentation and interception, but the treatment effect is poor when used alone; the chemical treatment includes chemical means such as flocculation, oxidation-reduction and complexation, but the cost is high when used alone; the biological treatment includes the use of microorganisms and plants to degrade ammonia nitrogen, nitrite and nitrate in water, but the cost is high when used alone.

[0004] Developing a high-efficiency, economical and stable treatment technology suitable for the factory breeding tail water of Penaeus vannamei to solve the bottleneck problem of the prior art has become an urgent need to ensure the green and sustainable development of aquaculture. SUMMARY

[0005] The application provides a process for removing pollutants in factory breeding tail water of Penaeus vannamei, which realizes efficient removal of pollutants in the factory breeding tail water of Penaeus vannamei by combining physical, chemical and biological treatment, improves the treatment efficiency of the factory breeding tail water of Penaeus vannamei, and realizes the standard discharge of the factory breeding tail water of Penaeus vannamei while efficiently recycling the factory breeding tail water of Penaeus vannamei.

[0006] The application provides a process for removing pollutants in factory breeding tail water of Penaeus vannamei, which includes the following steps:

[0007] (1) filtering the breeding wastewater to remove solid matters;

[0008] (2) adding composite bacteria to the filtered breeding wastewater for aeration treatment to obtain aeration wastewater, the adding amount of the composite bacteria is 6-8 g / L, and the composite bacteria include red cocci, bacillus subtilis, halotolerant brevitalea and photosynthetic bacteria at a weight ratio of (1-2):(2-3):(3-4):(0.8-1.5);

[0009] (3) adding 0.5wt%-1.0wt% of flocculants to the aeration wastewater, treating at 45-50 DEG C for 0.5-1 h, and filtering to obtain a first filtrate;

[0010] (4) adding 1.5-2.0wt% of modified activated carbon to the first filtrate, treating at 45-50℃ for 1-2h, and obtaining a second filtrate after filtration;

[0011] (5) treating the second filtrate by flowing through a macroporous adsorption resin at a feeding flow rate of (3-5) BV / h to obtain a third filtrate, and sterilizing the third filtrate.

[0012] This process solves the complex pollution of the white shrimp factory farming tail water through the complementary advantages of biological, chemical and physical treatment, and improves the treatment efficiency of the white shrimp factory farming tail water.

[0013] Through the application of composite bacteria, the whole process of white shrimp factory farming tail water can be synergistically purified, the ineffective adsorption of activated carbon on easily treated pollutants can be reduced, and the high-risk pollutants can be targeted removed: Rhodococcus target degradation of refractory organic matter in tail water, adsorption and degradation of trace pollutants; Bacillus subtilis efficiently decomposes particulate or macromolecular organic matter in tail water, such as protein, polysaccharide and chitin in leftover feed, shrimp manure and exuviae; Halobacillus can efficiently degrade complex organic matter, reduce oxygen consumption load of water body, utilize organic carbon source while realizing simultaneous conversion of nitrogen and phosphorus, and assist in nitrogen and phosphorus removal; Photosynthetic bacteria decompose small molecular organic matter such as amino acids and sugars in micro-anaerobic or anaerobic environment, assist in removal of COD and part of nitrogen and phosphorus, and can also secrete growth-promoting factors such as vitamin B and amino acids, improve the microecology of aquaculture water, and enhance the immunity of shrimps.

[0014] The addition of flocculants can efficiently remove suspended particulate matter, simultaneously remove particulate nitrogen and phosphorus, provide low-load water quality for subsequent activated carbon adsorption treatment, and also ensure stable effluent water quality; modified activated carbon and macroporous resin can efficiently adsorb antibiotics that cannot be degraded by composite bacteria, intercept heavy metal ions, reduce biological toxicity, and improve water quality and stability, which is suitable for the needs of recirculating aquaculture and provides finishing treatment for the purification process.

[0015] Specifically, the flocculant is at least one of polyaluminum ferric chloride, polyferric sulfate and polyaluminum chloride.

[0016] Optionally, the concentration of the Rhodococcus is 1×10 7 -1×10 8 CFU / ml.

[0017] Optionally, the concentration of the Bacillus subtilis is 1×10 7 -1×10 8 CFU / ml.

[0018] Optionally, the concentration of the Halobacillus is 1×10 9-1×10 10 CFU / ml.

[0019] Optionally, the concentration of the photosynthetic bacteria is 1×10 9 -1×10 10 CFU / ml.

[0020] Optionally, the preparation method of the modified activated carbon is as follows:

[0021] S1: placing the activated activated carbon in a dispersion solution of phosphoric acid and thiourea, and stirring to obtain a mixed solution;

[0022] S2: spray drying and calcining the mixed solution to obtain an intermediate A;

[0023] S3: placing the intermediate A in a mixed solution, drying after a certain period of treatment, to obtain the modified activated carbon.

[0024] The modified activated carbon is first expanded by phosphoric acid, and then co-doped with thiourea. The above treatment can optimize the pore structure and surface chemical properties of the activated carbon, solve the defects of insufficient pore volume or single active site of single modification, and provide strong guarantee for efficient adsorption. Moreover, the adsorption stability of the above improved modified porous carbon to impurities is improved, and more impurities can be absorbed with the addition of a small amount of modified activated carbon.

[0025] Specifically, the activation step of the activated carbon is as follows:

[0026] ① drying the activated carbon, heating to 600-800℃ under an inert gas atmosphere, and keeping the temperature for 1-3h;

[0027] ② after keeping the temperature, introducing water vapor, heating to 800-950℃, and keeping the temperature for 1-6h;

[0028] ③ after ending, cooling to room temperature, washing with deionized water until the filtrate pH is neutral, and finally drying to obtain the activated carbon.

[0029] Optionally, the weight ratio of the activated activated carbon, phosphoric acid and thiourea is 1: (0.8-1.2): (0.5-1.0).

[0030] Under this range, the maximum effect of phosphoric acid and thiourea can be fully exerted: phosphoric acid can form an ideal multi-stage pore network, and thiourea can make the N / S co-doping amount reach the best value. If the ratio of the three is unbalanced, the synergistic effect of phosphoric acid and thiourea will be weakened, and the dual enhancement of physical and chemical adsorption cannot be realized at the same time.

[0031] Optionally, the concentration of phosphoric acid in the dispersion solution of phosphoric acid and thiourea is 2wt%-6wt%.

[0032] Optionally, the temperature of the spray drying in step S2 is 150-250℃.

[0033] Optionally, the temperature of the calcination in step S2 is 800-1200℃, and the time is 0.2-1.0h.

[0034] Optionally, the heating rate of the calcination in step S2 is 50-80℃ / min.

[0035] Optionally, the mixed solution in step S3 is composed of glutamic acid, dodecylamine and water in a weight ratio of (0.5-0.6):(0.3-0.5):10.

[0036] The mixed solution further functionalizes the modified activated carbon: glutamic acid provides amino and carboxyl groups, has excellent biocompatibility, can form hydrogen bonds and chelation with pollutants, and improves the adsorption capacity for pollutants; dodecylamine as a cationic surfactant can adjust the surface charge of activated carbon, enhance electrostatic adsorption and hydrophobic interaction, further strengthen the surface adsorption performance on the basis of the modified activated carbon, and avoid the limitations of single component modification.

[0037] Optionally, the treatment temperature of step S3 is 40-50℃, and the treatment time is 3-4h.

[0038] The beneficial effects of the present application include but are not limited to:

[0039] 1. The process for removing pollutants in white shrimp factory farming tail water according to the present application, by combining physical, chemical and biological treatment, realizes efficient removal of pollutants in white shrimp factory farming tail water, improves the treatment efficiency of white shrimp factory farming tail water, and realizes standard discharge of white shrimp water while efficiently recycling the white shrimp water.

[0040] 2. The process for removing pollutants in white shrimp factory farming tail water according to the present application, by applying composite bacteria, realizes full-process synergistic purification of white shrimp factory farming tail water, improves the microecology of the farming water, and improves the immunity of the shrimp.

[0041] 3. The process for removing pollutants in white shrimp factory farming tail water according to the present application, by modifying the activated carbon, strengthens the surface adsorption performance, efficiently adsorbs antibiotic residues, traps heavy metal ions, reduces biological toxicity, and improves the sensory and stability of the water quality, and adapts to the needs of recirculating aquaculture. DETAILED DESCRIPTION

[0042] The present application will be described in detail below with reference to the examples, but the present application is not limited to these examples.

[0043] The raw materials in the examples and comparative examples of the present application are commercially available unless otherwise specified.

[0044] Rhodococcus ruber used in the examples of the present application is purchased from China Center for Type Culture Collection, with the preservation number of CCTCC NO: M20191008.

[0045] Bacillus subtilis used in the examples of the present application is purchased from China Center for Type Culture Collection, with the preservation number of CCTCC NO: M2020355.

[0046] Brevibacterium halotolerans used in the examples of the present application is purchased from China Center for Type Culture Collection, with the preservation number of CCTCC KB 20081310.

[0047] Photosynthetic bacteria used in the examples of the present application is purchased from China Center for Type Culture Collection, with the preservation number of CCTCC NO: M 2022251.

[0048] Bacillus velezensis used in Comparative Example 2 of the present application is purchased from China Center for Type Culture Collection, with the preservation number of CCTCC AB 200052.

[0049] Rhodococcus erythropolis used in Comparative Example 3 of the present application is purchased from China Center for Type Culture Collection, with the preservation number of CCTCC KA 2008001.

[0050] The methods used in the examples and comparative examples of the present application are conventional methods in the prior art unless otherwise specified.

[0051] Example 1

[0052] This example relates to a process for removing pollutants from the tail water of factory farming of Penaeus vannamei, comprising the following steps:

[0053] (1) filtering the farming wastewater to remove solid matters;

[0054] (2) adding a compound bacteria to the filtered farming wastewater for aeration treatment to obtain aeration wastewater, the addition amount of the compound bacteria is 6 g / L, and the compound bacteria comprises Rhodococcus ruber, Bacillus subtilis, Brevibacterium halotolerans and photosynthetic bacteria in a weight ratio of 1:2:3:0.8, the concentration of Rhodococcus ruber is 1×10 7 CFU / ml, the concentration of Bacillus subtilis is 1×10 8 CFU / ml; the concentration of Brevibacterium halotolerans is 1×10 9 CFU / ml; and the concentration of photosynthetic bacteria is 1×10 10 CFU / ml.

[0055] (3) adding 1.0wt% of the flocculant polymeric ferric sulfate to the aeration wastewater, treating at 45℃ for 1h, and filtering to obtain a first filtrate;

[0056] (4) adding 1.5wt% of the modified activated carbon to the first filtrate, treating at 50℃ for 1h, and filtering to obtain a second filtrate;

[0057] (5) treating the second filtrate by flowing through a macroporous adsorption resin at a feeding flow rate of 3BV / h to obtain a third filtrate, and sterilizing the third filtrate.

[0058] The preparation method of the modified activated carbon is as follows:

[0059] ① drying the activated carbon, heating to 800℃ under a nitrogen inert gas atmosphere, and maintaining the temperature for 1h;

[0060] ② after maintaining the temperature, introducing water vapor, heating to 950℃, and maintaining the temperature for 1h;

[0061] ③ after ending the heating, cooling to room temperature, washing with deionized water until the filtrate has a neutral pH, and finally drying to obtain the activated activated carbon;

[0062] S1: placing the activated activated carbon in a dispersion liquid of phosphoric acid and thiourea, stirring to obtain a mixed liquid, the weight ratio of the activated activated carbon, the phosphoric acid and the thiourea being 1:0.8:0.5, and the concentration of the phosphoric acid in the dispersion liquid of the phosphoric acid and the thiourea being 2wt%;

[0063] S2: spray drying the mixed liquid at a temperature of 150℃, and then calcining at a temperature of 800℃ for 1.0h at a heating rate of 50℃ / min to obtain an intermediate A;

[0064] S3: placing the intermediate A in a mixed solution composed of glutamic acid, dodecylamine and water at a weight ratio of 0.5:0.3:10, treating at a temperature of 40℃ for 4h, and drying to obtain the modified activated carbon.

[0065] Example 2

[0066] This example relates to a process for removing pollutants from the tail water of the factory farming of Penaeus vannamei, comprising the following steps:

[0067] (1) filtering the farming wastewater to remove solid matters;

[0068] (2) adding a compound bacteria to the filtered farming wastewater for aeration treatment to obtain aeration wastewater, the addition amount of the compound bacteria being 8g / L, and the compound bacteria comprising Rhodococcus ruber, Bacillus subtilis, Brevibacterium halophilum and photosynthetic bacteria at a weight ratio of 2:3:4:1.5, the concentration of the Rhodococcus ruber being 1×10 8CFU / ml, the concentration of Bacillus subtilis is 1×10⁻⁶. 7 CFU / ml; the concentration of salt-tolerant short bacilli was 1×10⁻⁶. 10 CFU / ml; the concentration of photosynthetic bacteria is 1×10⁻⁶. 9 CFU / ml;

[0069] (3) Add 0.5 wt% of polyaluminum chloride flocculant to the aerated wastewater, treat at 50°C for 0.5 h, and filter to obtain the first filtrate;

[0070] (4) Add 2.0 wt% of modified activated carbon to the first filtrate, treat at 45°C for 2 h, and filter to obtain the second filtrate.

[0071] (5) The second filtrate is passed through a mixed macroporous adsorption resin and processed at a loading flow rate of 5 BV / h to obtain the third filtrate, which is then sterilized.

[0072] The preparation method of modified activated carbon is as follows:

[0073] ①Dry the activated carbon and heat it to 600℃ in a nitrogen inert gas atmosphere, and keep it at that temperature for 3 hours;

[0074] ②After the heat preservation is completed, water vapor is introduced to raise the temperature to 800℃ and keep it warm for 6 hours;

[0075] ③ After the process is completed, cool to room temperature, rinse with deionized water until the pH of the filtrate is neutral, and finally dry to obtain the activated carbon;

[0076] S1: The activated carbon is placed in a dispersion of phosphoric acid and thiourea and stirred to obtain a mixed solution. The weight ratio of activated carbon, phosphoric acid and thiourea is 1:1.2:1.0, and the concentration of phosphoric acid in the dispersion of phosphoric acid and thiourea is 6 wt%.

[0077] S2: The mixture is spray-dried at 250°C and then calcined at 1200°C for 0.2 hours at a heating rate of 80°C / min to obtain intermediate A;

[0078] S3: The intermediate A is placed in a mixed solution of glutamic acid, dodecylamine and water in a weight ratio of 0.6:0.5:10 and treated at 50°C for 3 hours. After drying, the modified activated carbon is obtained.

[0079] Example 3

[0080] This embodiment relates to a process for removing pollutants from the wastewater of factory farming of Litopenaeus vannamei, including the following steps:

[0081] (1) Filter the aquaculture wastewater to remove solids;

[0082] (2) adding compound bacteria into the filtered aquaculture wastewater for aeration treatment to obtain aeration wastewater, the adding amount of the compound bacteria being 8 g / L, the compound bacteria including Rhodococcus ruber, Bacillus subtilis, Brevibacterium halophilum and photosynthetic bacteria at a weight ratio of 1.5:2:3:1.2, the concentration of the Rhodococcus ruber being 1×10 8 CFU / ml, the concentration of the Bacillus subtilis being 1×10 7 CFU / ml; the concentration of the Brevibacterium halophilum being 1×10 10 CFU / ml; and the concentration of the photosynthetic bacteria being 1×10 9 CFU / ml;

[0083] (3) adding 0.8wt% of flocculating agent polyaluminum ferric chloride in the aeration wastewater to the aeration wastewater, treating at 48℃ for 0.8h, and filtering to obtain a first filtrate;

[0084] (4) adding 1.8wt% of modified activated carbon in the first filtrate to the first filtrate, treating at 45℃ for 2h, and filtering to obtain a second filtrate;

[0085] (5) flowing and mixing the second filtrate through a macroporous adsorption resin to treat the second filtrate at a feeding flow rate of 5BV / h to obtain a third filtrate, and sterilizing the third filtrate.

[0086] The preparation method of the modified activated carbon is as follows:

[0087] ① drying the activated carbon, heating to 750℃ under a nitrogen inert gas atmosphere, and keeping the temperature for 2.5h;

[0088] ② after the temperature keeping, introducing water vapor, heating to 900℃, and keeping the temperature for 4h;

[0089] ③ after the end, cooling to room temperature, washing with deionized water until the pH of the filtrate is neutral, and finally drying to obtain the activated activated carbon;

[0090] S1: placing the activated activated carbon in a dispersion liquid of phosphoric acid and thiourea, stirring to obtain a mixed liquid, the weight ratio of the activated activated carbon, the phosphoric acid and the thiourea being 1:1.0:0.8, and the concentration of the phosphoric acid in the dispersion liquid of the phosphoric acid and the thiourea being 5wt%;

[0091] S2: spray drying the mixed liquid at a temperature of 200℃, and then calcining at a temperature of 1000℃ for 0.5h at a heating rate of 60℃ / min to obtain an intermediate A;

[0092] S3: placing the intermediate A in a mixed solution composed of glutamic acid, dodecylamine and water at a weight ratio of 0.5:0.4:10 for treatment at a temperature of 45℃ for 4h, and drying to obtain the modified activated carbon.

[0093] Example 4

[0094] Example 4 differs from Example 3 in that the weight ratio of activated activated carbon, phosphoric acid and thiourea after activation in step S1 is 1:1.3:0.8, and the rest is the same.

[0095] Example 5

[0096] Example 5 differs from Example 3 in that the weight ratio of activated activated carbon, phosphoric acid and thiourea after activation in step S1 is 1:1.0:1.1, and the rest is the same.

[0097] Example 6

[0098] Example 6 differs from Example 3 in that the mixed solution in step S3 is composed of glutamic acid, dodecylamine and water with a weight ratio of 0.7:0.4:10, and the rest is the same.

[0099] Example 7

[0100] Example 7 differs from Example 3 in that the mixed solution in step S3 is composed of glutamic acid, dodecylamine and water with a weight ratio of 0.5:0.6:10, and the rest is the same.

[0101] Example 8

[0102] Example 8 differs from Example 3 in that thioacetamide is used instead of thiourea in step S1, and the rest is the same.

[0103] Example 9

[0104] Example 9 differs from Example 3 in that the mixed solution of step S3 is added to the dispersion of phosphoric acid and thiourea in step S1, and there is no step S3, and the rest is the same.

[0105] Example 10

[0106] Example 10 differs from Example 3 in that the mixed solution in step S3 is composed of citric acid, octadecylamine and water with a weight ratio of 0.5:0.4:1, and the rest is the same.

[0107] Example 11

[0108] Example 11 differs from Example 3 in that there is no step S3, and the rest is the same.

[0109] Comparative Example 1

[0110] Comparative Example 1 differs from Example 3 in that the amount of composite bacteria added in step (2) is 9 g / L, and the rest is the same.

[0111] Comparative Example 2

[0112] The difference between Comparative Example 2 and Example 3 is that Bacillus velezensis is used instead of Brevibacterium halophilum in the composite bacteria in step (2), and the rest are the same.

[0113] Comparative Example 3

[0114] The difference between Comparative Example 3 and Example 3 is that Rhodococcus ruber is used instead of Rhodococcus rhodochrous in the composite bacteria in step (2), and the rest are the same.

[0115] Comparative Example 4

[0116] The difference between Comparative Example 4 and Example 3 is that the composite bacteria in step (2) include Rhodococcus rhodochrous, Bacillus subtilis, Brevibacterium halophilum, and photosynthetic bacteria in a weight ratio of 2.4:3.2:3:1.2, and the rest are the same.

[0117] Comparative Example 5

[0118] The difference between Comparative Example 5 and Example 3 is that the composite bacteria in step (2) include Rhodococcus rhodochrous, Bacillus subtilis, Brevibacterium halophilum, and photosynthetic bacteria in a weight ratio of 1.5:2:4.2:1.7, and the rest are the same.

[0119] Comparative Example 6

[0120] The difference between Comparative Example 6 and Example 3 is that unmodified activated carbon is used in step (3), there is no step S1-S3, and only the activated activated carbon obtained by steps ①-③ is used to treat the first filtrate, and the rest are the same.

[0121] Test Example

[0122] The water samples treated by the treatment processes in the above examples and comparative examples are tested for total nitrogen, total phosphorus, chemical oxygen demand, suspended particulate matter, and pH value, and the test results are shown in Table 1, and the specific test methods are as follows:

[0123] Total nitrogen: after digestion at 120°C for 30 min using alkaline potassium persulfate, it is determined by ultraviolet spectrophotometry, and the determination standard is HJ 636-2012;

[0124] Total phosphorus: after digestion at 120°C for 30 min using potassium persulfate, it is determined by ammonium molybdate spectrophotometry, and the determination standard is GB 11893-1989;

[0125] Chemical oxygen demand (COD): using dichromate at 170°C for strong oxidation digestion for 2h, the determination standard is GB / T11914-1989;

[0126] Suspended particulate matter (SS): the water sample is filtered using a 0.45μm filter membrane, dried at 103-105°C to constant weight, and then weighed to calculate the difference, and the determination standard is GB 11901-1989;

[0127] pH: measured by glass electrode method, and the measurement standard is GB / T 6920-1986.

[0128] Table 1

[0129]

[0130] According to the data in Table 1, the water samples treated by Examples 1-11 achieved efficient removal of pollutants in the tail water of Penaeus vannamei aquaculture, meeting the standard of circulating water samples, and the treatment effect of Example 3 was the best. The treatment of water samples of Comparative Examples 1-6 was obviously poor, indicating that the strain compound in the application had a significant effect on the treatment of pollutants in the water sample, and the activated carbon after two-step modification had stronger adsorption. The adsorption effect of Example 9 which combined the two-step modification into one step and Example 11 which only modified the activated carbon in one step was obviously poorer than that of Example 3.

[0131] The above description of the examples is for the purpose of facilitating the understanding and use of the application by those of ordinary skill in the art. Those skilled in the art can obviously make various modifications to these examples, and apply the general principles described herein to other examples without having to go through creative labor. Therefore, the present application is not limited to the above examples, and the improvements and modifications made by those skilled in the art according to the disclosure of the present application without departing from the scope of the present application should be within the protection scope of the present application.

Claims

1. A process for removing pollutants from the wastewater of factory-farmed Litopenaeus vannamei, characterized in that, Includes the following steps: (1) Filter the aquaculture wastewater to remove solids; (2) Add compound bacteria to the filtered aquaculture wastewater for aeration treatment to obtain aerated wastewater. The amount of compound bacteria added is 6-8 g / L. The compound bacteria include Rhodococcus rubrum, Bacillus subtilis, salt-tolerant short bacilli and photosynthetic bacteria in a weight ratio of (1-2):(2-3):(3-4):(0.8-1.5). (3) Add 0.5wt%-1.0wt% of flocculant to the aerated wastewater, treat at 45-50℃ for 0.5-1h, and filter to obtain the first filtrate; (4) Add 1.5-2.0 wt% of modified activated carbon to the first filtrate, treat at 45-50℃ for 1-2 h, and filter to obtain the second filtrate; (5) The second filtrate is passed through a mixed macroporous adsorption resin and treated at a loading flow rate of (3-5) BV / h to obtain the third filtrate, which is then sterilized. The method for preparing the modified activated carbon is as follows: S1: The activated carbon is placed in a dispersion of phosphoric acid and thiourea and stirred to obtain a mixture. The weight ratio of the activated carbon, phosphoric acid and thiourea is 1:(0.8-1.2):(0.5-1.0). S2: The mixture is spray-dried and calcined to obtain intermediate A; S3: The intermediate A is placed in a mixed solution, treated for a certain period of time, and then dried to obtain the modified activated carbon. The mixed solution is composed of glutamic acid, dodecylamine, and water in a weight ratio of (0.5-0.6):(0.3-0.5):

10. Modified activated carbon is first expanded by phosphoric acid, and then co-doped with thiourea to optimize the pore structure and surface chemical properties of the activated carbon; glutamic acid provides amino and carboxyl bifunctional groups, which form hydrogen bonds and chelation with pollutants to improve the adsorption capacity of pollutants; Dodecylamine, as a cationic surfactant, regulates the surface charge of activated carbon, enhancing electrostatic adsorption and hydrophobic effects.

2. The process for removing pollutants from the effluent of factory-farmed Litopenaeus vannamei according to claim 1, characterized in that, The concentration of the Rhodococcus is 1×10⁻⁶. 7 -1×10 8 CFU / ml; The concentration of Bacillus subtilis was 1×10⁻⁶. 7 -1×10 8 CFU / ml; The concentration of the salt-tolerant short bacilli was 1×10⁻⁶. 9 -1×10 10 CFU / ml; The concentration of the photosynthetic bacteria is 1×10⁻⁶. 9 -1×10 10 CFU / ml.

3. The process for removing pollutants from the effluent of factory-farmed Litopenaeus vannamei according to claim 1, characterized in that, The concentration of phosphoric acid in the dispersion of phosphoric acid and thiourea is 2wt%-6wt%.

4. The process for removing pollutants from the effluent of factory-farmed Litopenaeus vannamei according to claim 1, characterized in that, The spray drying temperature in step S2 is 150-250℃.

5. The process for removing pollutants from the effluent of factory-farmed Litopenaeus vannamei according to claim 1, characterized in that, The calcination temperature in step S2 is 800-1200℃, and the time is 0.2-1.0h.

6. The process for removing pollutants from the effluent of factory-farmed Litopenaeus vannamei according to claim 1, characterized in that, The heating rate for calcination in step S2 is 50-80℃ / min.

7. The process for removing pollutants from the effluent of factory-farmed Litopenaeus vannamei according to claim 1, characterized in that, The processing temperature in step S3 is 40-50℃, and the processing time is 3-4 hours.

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