Livestock wastewater treatment process based on biological synergist

Abstract

The invention relates to the technical field of wastewater treatment, in particular to a livestock wastewater treatment process based on a biological synergist. The method overcomes the problem of poor removal effect on organic matters, ammonia nitrogen and total phosphorus in livestock wastewater in a traditional wastewater treatment process. A biological synergist I and a synergist II are prepared, the preparation method is optimized, the application proportion of the biological synergist I and the synergist II in different pools is reasonably adjusted, the backflow stage in the process is reasonably adjusted, and parameters such as illumination, dissolved oxygen and hydraulic retention time of each stage are adjusted according to the process steps. Therefore, organic matters, ammonia nitrogen and total phosphorus in the livestock wastewater can be effectively removed, and the livestock wastewater meets the discharge standard.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and particularly to a livestock wastewater treatment process based on a biological synergist. Background Art

[0002] With the large-scale and intensive development of the livestock and poultry breeding industry, the generation amount of livestock and poultry wastewater has increased sharply. Livestock and poultry wastewater is rich in high-concentration organic matters, nitrogen, phosphorus, pathogens and other pollutants. If directly discharged without effective treatment, it will cause serious pollution to the soil, water body and atmospheric environment, threatening the ecological balance and human health.

[0003] Taking the activated sludge method as an example, the typical steps of traditional livestock and poultry wastewater treatment processes are as follows: The wastewater is first intercepted by a grid to remove larger suspended solids and sundries to prevent subsequent equipment blockage; then it flows into a grit chamber, and inorganic particles such as sand grains are removed by gravity sedimentation; subsequently, it enters the primary sedimentation tank, and part of the suspended solids and organic matters are separated by natural sedimentation; then it enters the aeration tank, and microorganisms are brought into full contact with the wastewater through aeration to decompose organic matters; then it enters the secondary sedimentation tank to achieve the separation of mud and water, and the settled water is discharged up to standard, and part of the settled sludge is refluxed to the aeration tank, and part is discharged as surplus sludge from the treatment system. However, traditional processes have many drawbacks. Especially for the livestock and poultry wastewater from pig breeding, the treatment efficiency is low, and it is difficult to remove pollutants such as high-concentration organic matters, nitrogen and phosphorus in the wastewater.

[0004] The traditional treatment process has a weak anti-shock load capacity. Once the wastewater quality and quantity fluctuate greatly, the treatment effect will be greatly reduced. The nitrogen and phosphorus removal effects are not ideal and cannot meet the increasingly stringent current environmental protection standards. With the continuous improvement of environmental protection requirements, it is urgent to develop a more efficient, stable and low-cost livestock and poultry wastewater treatment process. Summary of the Invention

[0005] The purpose of the present invention is to provide a livestock wastewater treatment process based on a biological synergist. The present invention overcomes the problem of poor removal effects of organic matters, ammonia nitrogen and total phosphorus in livestock and poultry wastewater in traditional wastewater treatment processes. By preparing biological synergist one and synergist two, optimizing the preparation method, reasonably adjusting the application ratios of biological synergist one and synergist two in different tanks, reasonably adjusting the reflux stage in the process, and adjusting parameters such as light, dissolved oxygen (DO value) and hydraulic retention (HRT) time in each stage to adapt to the process steps, so that the organic matters, ammonia nitrogen and total phosphorus in livestock and poultry wastewater can be effectively removed and meet the discharge standards.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] The present invention provides a livestock wastewater treatment process based on a biological synergist. The treatment process is as follows:

[0008] After the wastewater removes larger suspended solids and floating substances through the grille, it enters the storage pool, where a simple biochemical reaction takes place to remove a small part of the waste. The mixture in the storage pool is pumped into the separator, where solid-liquid separation occurs. The separated solids enter the waste residue yard, and the separated wastewater enters the air flotation pool, where some suspended pollutants are removed, and the effluent enters the adjustment pool. The adjustment pool obtains the livestock wastewater to be treated in the present invention, with initial COD (chemical oxygen demand), ammonia nitrogen, and total phosphorus concentrations of 9486 mg / L, 413 mg / L, and 31 mg / L respectively.

[0009] A livestock wastewater treatment process based on a biological enhancer, and the treatment process is as follows:

[0010] S1 The wastewater enters the symbiotic pool through pipeline 1, stops after being illuminated at 5000 - 7000 lux for 2.5 - 4.5 h, with intermittent illumination until the treatment in the symbiotic pool ends after 5 - 7.5 d. The algae-treated wastewater obtained enters the aerobic pool;

[0011] S2 Start the vertical aerator 1, with the DO value being 1.8 - 4.0 mg / L and the HRT value being 10 - 12 h. The treated wastewater flows back to the symbiotic pool through the air lift in pipeline 3. Start the vertical aerator 2 to make the DO value in the symbiotic pool 1.8 - 3.5 mg / L. After aeration for 2.5 - 4.5 h, illumination is carried out, with irradiation at 7000 lux for 3.5 - 5.0 h. Aeration and illumination are alternated until the treatment in the symbiotic pool ends after 3.5 - 5 d. The two-stage illuminated wastewater obtained enters the aerobic pool again through pipeline 2;

[0012] S3 Start the vertical aerator 1. The three-stage aerated wastewater obtained enters the anaerobic pool through pipeline 4. After fully reacting for 2.5 - 4 d of HRT, it passes through the air lift in pipeline 5 and flows back into the aerobic pool;

[0013] S4 Start the vertical aerator 1. The four-stage aerated wastewater obtained enters the anaerobic pool again through pipeline 4, flows out through pipeline 6 after treatment, and the secondary anaerobically treated wastewater is introduced into the three-dimensional particle electrode electro-Fenton reactor equipped with an ultrasonic transducer to obtain the livestock wastewater based on the biological enhancer.

[0014] Preferably, the addition ratios of the mixed algae in the symbiotic pool, the biological enhancer 1 in the aerobic pool, and the biological enhancer 2 in the anaerobic pool to the livestock wastewater are 30 - 50 g:1 L, 20 - 60 g:1 L, and 10 - 45 g:1 L respectively.

[0015] Preferably, the preparation method of the strain concentrate in the biological enhancer 1 is as follows:

[0016] The preparation method of the concentrated solution of Nitrosomonas europaea (ATCC 19718) is as follows: In a 50 L fermenter, the inoculation amount of the Nitrosomonas europaea seed solution is 3 L, and the concentration of the Nitrosomonas europaea seed solution is 10 8 CFU / mL; ammonium chloride in the fermenter is used as the nitrogen source with a concentration of 1.5 g / L; potassium dihydrogen phosphate provides phosphorus with a concentration of 2.5 g / L; magnesium sulfate heptahydrate provides magnesium ions with a concentration of 0.5 g / L; sodium bicarbonate is used as the carbon source and pH buffer with a concentration of 2 g / L; ferric chloride, manganese chloride, and zinc chloride are used as trace element supplements with concentrations of 0.05 g / L, 0.02 g / L, and 0.06 g / L respectively; the dissolved oxygen DO value is controlled at 4 mg / L, the pH of the fermentation is adjusted to 7.5, the fermentation is carried out until it enters the stationary phase, and the fermentation is stopped after 5 days; the obtained Nitrosomonas europaea solution is concentrated 50 times to obtain the concentrated solution of Nitrosomonas europaea.

[0017] The preparation method of the concentrated solution of Nitrosomonas mesophila (ATCC 25978) is as follows: In a 50 L fermenter, the inoculation amount of the Nitrosomonas mesophila seed solution is 2.5 L, and the concentration of the Nitrosomonas mesophila seed solution is 10 8 CFU / mL; ammonium chloride in the fermenter is used as the nitrogen source with a concentration of 2 g / L; potassium dihydrogen phosphate provides phosphorus with a concentration of 2.5 g / L; magnesium sulfate heptahydrate provides magnesium ions with a concentration of 0.5 g / L; sodium bicarbonate is used as the carbon source and pH buffer with a concentration of 3 g / L; ferric chloride, manganese chloride, and zinc chloride are used as trace element supplements with concentrations of 0.05 g / L, 0.02 g / L, and 0.06 g / L respectively; the dissolved oxygen DO value is controlled at 4 mg / L, the pH of the fermentation is adjusted to 7.5, the fermentation is carried out until it enters the stationary phase, and the fermentation is stopped after 6.5 days; the obtained Nitrosomonas mesophila solution is concentrated 50 times to obtain the concentrated solution of Nitrosomonas mesophila.

[0018] The above two kinds of bacteria are mainly responsible for oxidizing ammonia nitrogen to nitrite, which is the first step of nitrification. The reaction formula is: 2NH 4 + +3O 2 →2NO 2 - +2H 2 O + 4H + ; This process converts the ammonia nitrogen in the pig and poultry wastewater into nitrite, laying a foundation for the subsequent active Nitrobacter and Nitrobacter winogradskyi to further oxidize nitrite to nitrate, thereby achieving the removal of ammonia nitrogen in the wastewater.

[0019] The preparation method of the concentrated solution of Nitrobacter winogradskyi (ATCC 25391) is as follows: In a 50 L fermenter, the inoculation amount of the Nitrobacter winogradskyi seed solution is 2.5 L, and the concentration of the Nitrobacter winogradskyi seed solution is 10 8CFU / mL; Sodium nitrite in the fermenter is used as a nitrogen source with a concentration of 1.5 g / L; Potassium dihydrogen phosphate provides phosphorus element with a concentration of 1 g / L; Magnesium sulfate heptahydrate provides magnesium ions with a concentration of 0.4 g / L; Sodium bicarbonate is used as a carbon source and a pH buffer with a concentration of 2 g / L; Ferric chloride, manganese chloride and zinc chloride are used as trace element supplements with concentrations of 0.05 g / L, 0.02 g / L and 0.06 g / L respectively; The dissolved oxygen DO value is controlled at 4 mg / L, the pH of the fermentation is adjusted to 7.0, the fermentation temperature is 30 °C, and the fermentation is stopped after 7 days when it enters the stationary phase; The obtained Nitrobacter winogradskyi liquid is concentrated 50 times to obtain a Nitrobacter winogradskyi concentrated liquid.

[0020] The preparation method of the concentrated liquid of Nitrobacter agilis (ATCC 14123) is as follows: In a 50 L fermenter, the inoculation amount of the Nitrobacter agilis seed liquid is 2.5 L, and the concentration of the Nitrobacter agilis seed liquid is 10 8 CFU / mL; Sodium nitrite in the fermenter is used as a nitrogen source with a concentration of 2 g / L; Potassium dihydrogen phosphate provides phosphorus element with a concentration of 0.8 g / L; Magnesium sulfate heptahydrate provides magnesium ions with a concentration of 0.5 g / L; Sodium bicarbonate is used as a carbon source and a pH buffer with a concentration of 2.6 g / L; Ferric chloride, manganese chloride and zinc chloride are used as trace element supplements with concentrations of 0.05 g / L, 0.02 g / L and 0.06 g / L respectively; The dissolved oxygen DO value is controlled at 4 mg / L, the pH of the fermentation is adjusted to 7.5, the fermentation temperature is 30 °C, and the fermentation is stopped after 6 days when it enters the stationary phase; The obtained Nitrobacter agilis liquid is concentrated 50 times to obtain a Nitrobacter agilis concentrated liquid.

[0021] The above two kinds of bacteria further oxidize nitrite to nitrate. This process is the second step of nitrification, and the reaction formula is: 2NO 2 - +O 2 →2NO 3 - Through this process, the concentration of nitrite in the wastewater is reduced, and at the same time, it provides a substrate for the denitrification of subsequent denitrifying bacteria.

[0022] The preparation method of the concentrated liquid of Pseudomonas aeruginosa (ATCC 15442) is as follows: In a 50 L fermenter, the inoculation amount of the Pseudomonas aeruginosa seed liquid is 2.5 L, and the concentration of the Pseudomonas aeruginosa seed liquid is 10 9CFU / mL; In the fermenter, peptone is used as the organic nitrogen source with a concentration of 8 g / L; glucose provides the carbon source with a concentration of 15 g / L; potassium nitrate is used as the inorganic nitrogen source with a concentration of 3 g / L; the concentration of potassium dihydrogen phosphate is 1.0 g / L; the concentration of dipotassium hydrogen phosphate is 1.2 g / L; magnesium sulfate heptahydrate provides magnesium ions with a concentration of 0.4 g / L; the concentration of ferrous sulfate heptahydrate is 0.05 g / L; pantothenic acid is used as a growth factor with an added concentration of 0.002 g / L; the pH is maintained at 7.5 during fermentation, fermentation is carried out at 30 °C, the average DO is 4 mg / L, and fermentation stops after 2.8 d; after concentrating 50 times, a concentrated solution of Pseudomonas aeruginosa is obtained.

[0023] Pseudomonas aeruginosa has a strong ability to decompose organic matter. Pig and poultry wastewater contains a large amount of organic substances such as proteins, fats, and carbohydrates. Pseudomonas aeruginosa can secrete various extracellular enzymes, such as proteases, lipases, amylases, etc., to decompose these macromolecular organic substances into small molecules such as amino acids, fatty acids, and glucose, and then further absorb and utilize them to reduce the COD in the wastewater. It can also decompose and transform some toxic and harmful substances in pig and poultry wastewater, such as certain phenolic compounds and pesticide residues, and degrade them into relatively harmless substances through its own metabolic pathways to reduce the toxicity of the wastewater.

[0024] The preparation method of the concentrated solution of Candida tropicalis (CICC 1956) is as follows: In a 50 L fermenter, the inoculation amount of the Candida tropicalis seed solution is 6.0 L, and the concentration of the yeast seed solution is 10 8 CFU / mL; In the fermenter, glucose provides the carbon source with a concentration of 20 g / L; yeast extract powder is used as the nitrogen source with a concentration of 10 g / L; ammonium sulfate is 1.5 g / L; the concentration of dipotassium hydrogen phosphate is 2 g / L; magnesium sulfate heptahydrate provides magnesium ions with a concentration of 0.8 g / L; the average value of dissolved oxygen DO during fermentation is controlled at 5.5 mg / L, the pH of fermentation is adjusted to 7.0, the fermentation temperature is 32 °C, and fermentation stops when it enters the stationary phase after 2.5 d; after concentrating the obtained Candida tropicalis solution 50 times, a concentrated solution of Candida tropicalis is obtained.

[0025] Candida tropicalis can decompose carbohydrates such as sugars in livestock and poultry wastewater, such as starch, glucose, sucrose, etc. Yeast decomposes these sugars into substances such as carbon dioxide and alcohol through its own metabolic enzymes, and can also utilize some nitrogen-containing organic substances for growth.

[0026] The preparation method of the concentrated solution of Gloeophyllum trabeum (China Microbial Strain Platform No. bio-26062) is as follows: In a 50 L fermenter, the inoculation amount of the Gloeophyllum trabeum seed solution is 6.0 L, and the concentration of the Gloeophyllum trabeum seed solution is 10 8CFU / mL; Starch in the fermenter provides a carbon source with a concentration of 20 g / L; yeast extract powder provides an organic nitrogen source with a concentration of 5 g / L; urea provides an inorganic nitrogen source with a concentration of 1 g / L; ammonium nitrate provides an inorganic nitrogen source with a concentration of 1.5 g / L; manganese sulfate 0.05 g / L; potassium dihydrogen phosphate 1.5 g / L; magnesium sulfate heptahydrate 0.8 g / L; the average dissolved oxygen DO during fermentation is controlled at 7.0 mg / L, the pH of fermentation is adjusted to 7.0, the fermentation temperature is 28 °C, fermentation continues until the stationary phase is reached, and fermentation stops after 12 d; the obtained Gloeophyllum trabeum is concentrated 50 times to obtain a concentrated Gloeophyllum trabeum solution.

[0027] Gloeophyllum trabeum can decompose cellulose, hemicellulose, lignin, protein, and fat substances in livestock and poultry wastewater; livestock and poultry feeds usually contain a large amount of plant fibers, which include cellulose and hemicellulose, and they enter the wastewater with livestock and poultry manure. Gloeophyllum trabeum can secrete cellulase and hemicellulase. Among them, cellulase can decompose cellulose into cellobiose and glucose, and hemicellulase can degrade hemicellulose into monosaccharides such as xylose and mannose. In this way, Gloeophyllum trabeum reduces the content of cellulose and hemicellulose in livestock and poultry wastewater, reduces the organic load of the wastewater, and at the same time the generated monosaccharides may also provide a carbon source for the growth of other microorganisms. Although Gloeophyllum trabeum does not have as strong a lignin degradation ability as white rot fungi (the suitable growth environment pH is 5.0 - 6.5, which is not suitable for the pH growth environment of the present invention), it also has a certain ability to modify and decompose lignin. There may be a small amount of lignin components in livestock and poultry feeds. After entering the wastewater, Gloeophyllum trabeum can produce some oxidases, such as laccase, to damage the structure of lignin to a certain extent, making its molecular structure smaller and more easily decomposed by other microorganisms or removed from the wastewater. Livestock and poultry wastewater contains proteins that have not been completely digested and absorbed by livestock and poultry. Gloeophyllum trabeum can secrete protease to hydrolyze proteins into polypeptides and amino acids. These small-molecule polypeptides and amino acids can be used by Gloeophyllum trabeum itself as nitrogen and carbon sources, or can be further decomposed and metabolized by other microorganisms, and finally converted into substances such as ammonia and carbon dioxide, thereby reducing the protein content in the wastewater. There may be some fat substances in livestock and poultry wastewater. Gloeophyllum trabeum can produce lipase to decompose fat into glycerol and fatty acids. Glycerol can be further metabolized and utilized by microorganisms, and fatty acids can be gradually degraded through pathways such as β-oxidation, reducing the fat content in the wastewater and improving the water quality of the wastewater.

[0028] The preparation method of the concentrated solution of Streptomyces griseus (ATCC 23345) is as follows: In a 50 L fermenter, the inoculation amount of the Streptomyces griseus seed liquid is 6.5 L, and the concentration of the Streptomyces griseus seed liquid is 10 8CFU / mL; Starch in the fermenter provides the carbon source with a concentration of 20 g / L; soybean cake powder provides the nitrogen source with a concentration of 10 g / L; potassium dihydrogen phosphate 0.8 g / L; calcium carbonate 2 g / L; the average value of dissolved oxygen DO during the fermentation process is controlled at 6.0 mg / L, the pH of the fermentation is adjusted to 7.0, the fermentation temperature is 30 °C, and the fermentation stops after 6 d when it enters the stationary phase; the obtained Streptomyces griseus is concentrated 50 times to obtain the concentrated Streptomyces griseus solution.

[0029] Streptomyces griseus can degrade various nitrogen-containing organic compounds, complex polysaccharides, etc. It can decompose nitrogen-containing organic compounds such as proteins and amino acids, as well as polysaccharide substances such as starch in livestock and poultry wastewater.

[0030] The denitrifying bacterium is Pseudomonas denitrificans (ATCC 13867)

[0031] The preparation method of the concentrated Pseudomonas denitrificans solution is as follows: in a 50 L fermenter, the inoculation amount of the Pseudomonas denitrificans seed liquid is 1.5 L, and the concentration of the Pseudomonas denitrificans seed liquid is 10 8 CFU / mL; Sodium acetate in the fermenter provides the carbon source with a concentration of 10 g / L; potassium nitrate provides the nitrogen source with a concentration of 2 g / L; potassium dihydrogen phosphate 0.8 g / L; magnesium sulfate heptahydrate 0.5 g / L; the average value of dissolved oxygen DO during the fermentation process is controlled below 0.3 mg / L, the pH of the fermentation is adjusted to 7.0, the fermentation temperature is 30 °C, and the fermentation stops after 2 d when it enters the stationary phase; the obtained Pseudomonas denitrificans is concentrated 50 times to obtain the concentrated Pseudomonas denitrificans solution.

[0032] Pseudomonas denitrificans acts on nitrates and nitrites in pig and poultry wastewater. Under anaerobic or anoxic conditions, it can use nitrates or nitrites as electron acceptors, reduce them to nitrogen gas and release it into the air, thereby achieving the removal of nitrogen elements in the wastewater.

[0033] The preparation method of the concentrated Acinetobacter calcoaceticus (original number BRI-00279 of the Institute of Biotechnology, Chinese Academy of Agricultural Sciences) solution is as follows: in a 50 L fermenter, the inoculation amount of the Acinetobacter calcoaceticus seed liquid is 1.0 L, and the concentration of the Acinetobacter calcoaceticus seed liquid is 10 8 CFU / mL; Glucose in the fermenter provides the carbon source with a concentration of 15 g / L; beef extract provides the nitrogen source with a concentration of 5 g / L; potassium dihydrogen phosphate 1.0 g / L; magnesium sulfate heptahydrate 0.5 g / L; the average value of dissolved oxygen DO during the fermentation process is controlled at 5 mg / L, the pH of the fermentation is adjusted to 7.0, the fermentation temperature is 30 °C, and the fermentation stops after 1.8 d when it enters the stationary phase; the obtained Acinetobacter calcoaceticus is concentrated 50 times to obtain the concentrated Acinetobacter calcoaceticus solution.

[0034] Under aerobic conditions, Acinetobacter calcoaceticus absorbs phosphate in livestock wastewater and converts it into polyphosphate, which is stored in the cells. With the growth and proliferation of the bacteria, phosphorus is fixed in the cells. Through subsequent treatments such as sludge sedimentation, the phosphorus-containing bacteria are separated from the livestock wastewater, thus achieving phosphorus removal.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] 1. By diluting concentrated solutions of various activated strains according to a fixed ratio, mixing them according to the ratio, and adding various enzyme solutions to obtain a mixed solution; by loading the mixed solution onto UIO-66 material, the contact area between the wastewater and the strains and enzymes is increased. Then, by binding with sodium alginate and chitosan, the binding strength of the bacterial solution, enzymes, and UIO-66 material is improved. After cross-linking sodium alginate and chitosan with calcium chloride, solidified microspheres are further formed; by optimizing the addition ratio of the biological enhancer I and livestock wastewater in the aerobic tank, as well as the DO value and HRT value when the wastewater first enters the aerobic tank, the present invention process has a good removal effect on COD in pig and livestock wastewater.

[0037] 2. During the preparation of the carrier UIO-66 of the biological enhancer I, by adding compounds containing titanium and indium, titanium and indium are embedded in UIO-66 through chemical bonds. In the aerobic tank, the wastewater flows back to the symbiotic tank through pipeline II. Under light conditions, the biological enhancer I and algae decompose organic matter. At the same time, the synthesized UIO-66 material has the function of generating photogenerated electrons, producing free radicals to scavenge organic matter. By adjusting the dosage ratio of the mixed algae and the biological enhancer I in the symbiotic tank and the aerobic tank, as well as adjusting the light and HRT value when the wastewater first enters the symbiotic tank, and alternating the DO value, light, and aeration when the wastewater enters the symbiotic tank after the first reflux, the present invention process has a good removal rate of COD.

[0038] 3. By optimizing the preparation method of the biological enhancer II and loading the prepared biological enhancer II on an ammoniated silica gel column, the loss of anaerobic bacteria caused by the wastewater flowing back from the anaerobic tank to the aerobic tank is avoided, and the negative impact of the toxins produced by anaerobic bacteria on aerobic bacteria after the mixing of anaerobic bacteria and aerobic bacteria is avoided. By adjusting the HRT value of the anaerobic tank, as well as the addition ratio of the biological enhancer II and livestock wastewater in the anaerobic tank, and the synergistic effect of the biological enhancer I and the biological enhancer II, the concentrations of ammonia nitrogen and total phosphorus in the wastewater are jointly reduced.

[0039] 4. By adjusting the wastewater treatment process steps and reasonably setting the number of cycles, the wastewater treated in the aerobic tank is refluxed into the symbiotic tank, enters the aerobic tank after exposure and aeration treatment, and then enters the anaerobic tank from the aerobic tank. After being treated in the anaerobic tank, it is refluxed into the aerobic tank. After treatment, it passes through the anaerobic tank and the ultrasonic-based electrode electro-Fenton reactor, so as to achieve good removal effects on COD, ammonia nitrogen, and total phosphorus in livestock and poultry wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The figure is a process flow chart of the livestock and poultry wastewater treatment process based on the biological enhancer of the present invention.

[0041] In the figure: 1. Symbiotic tank; 2. Aerobic tank; 3. Anaerobic tank; 4. Three-dimensional particle electrode electro-Fenton reactor equipped with ultrasonic transducers; 11. Vertical aerator II; 21. Vertical aerator I; 22. Air lift of pipeline II; 31. Solidification product of biological enhancer II and silica gel column; 32. Air lift of pipeline V. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0043] Please refer to Figure 1 , the present invention provides a livestock and poultry wastewater treatment process based on a biological enhancer, and the technical solution is as follows:

[0044] Example 1

[0045] S1 The livestock and poultry wastewater enters the symbiotic tank 1 through pipeline 1. After 1 hour, the light is turned on, the light intensity is 7000 lux, the light is turned off after 4 hours of lighting for 2 hours, and then the light is turned on again. The pH of the symbiotic tank 1 is maintained at 7.5 until the end of a HRT of 7.5 days in the symbiotic tank 1, and the light is turned off to obtain algae-treated livestock and poultry wastewater. When the sludge concentration in the symbiotic tank 1 is lower than 10 g / L, mixed algae are supplemented; the algae-treated livestock and poultry wastewater enters the symbiotic tank 2;

[0046] S2 Start the vertical aerator 21 for the first time, so that the DO value in the symbiotic pond 2 is 3.2 mg / L, keep the pH of the symbiotic pond 2 at 7.0, and the HRT value of the symbiotic pond 2 is 10 h. Then, return the aerobic-treated livestock and poultry wastewater to the symbiotic pond 1 through the air-lift device 22 of pipeline three. Start the vertical aerator 11, so that the DO value in the symbiotic pond 1 is 3.0 mg / L. After aeration for 4 h, carry out illumination, irradiate with 7000 lux for 4 h, and alternate aeration and illumination until the HRT of the symbiotic pond 1 ends for 5 d to obtain the second-stage illuminated livestock and poultry wastewater; and add biological enhancer 1 when the sludge concentration in the symbiotic pond 2 is lower than 8 g / L; the second-stage illuminated livestock and poultry wastewater enters the symbiotic pond 2 again through pipeline two;

[0047] S3 Start the vertical aerator 21 again, so that the DO value in the symbiotic pond 2 is 4.0 mg / L, keep the pH of the symbiotic pond 2 at 7.0, and the HRT value of the symbiotic pond 2 is 8 h to obtain the three-stage aerated livestock and poultry wastewater; the three-stage aerated livestock and poultry wastewater enters the anaerobic pond 3 through pipeline four, adjust the pH to 7.0, and the DO value is 0.1 mg / L. After fully reacting for a HRT of 3.5 d, pass through the air-lift device 32 of pipeline five and return to the symbiotic pond 2 again. Add biological enhancer 2 when the sludge concentration in the anaerobic pond 3 is lower than 5 g / L;

[0048] S4 Start the vertical aerator 21 for the third time, maintain the concentration in the symbiotic pond 2 at 4.0 mg / L and the pH at 7.0, adjust the HRT value of the symbiotic pond 2 to 7 h, and obtain the four-stage aerated livestock and poultry wastewater after a HRT time; the four-stage aerated livestock and poultry wastewater enters the anaerobic pond 3 through pipeline four twice, reacts with denitrifying bacteria for a HRT value of 5 h, and then flows out through pipeline six to obtain the secondary anaerobically treated livestock and poultry wastewater; outside the three-dimensional particle electrode electro-Fenton reactor 4 equipped with an ultrasonic transducer externally, apply a high-frequency pulsed voltage, and at the same time start the ultrasonic generator. The high-frequency pulsed voltage is 15 V and the ultrasonic frequency is 40 kHz. After introducing the secondary anaerobically treated livestock and poultry wastewater, adjust the pH to 6.5 and treat it at 25 °C for 3 h; after flowing out through pipeline seven, adjust the pH to 7.0 to obtain the livestock and poultry wastewater based on the biological enhancer;

[0049] The preparation method of the biological enhancer is as follows: The biological enhancer includes biological enhancer 1 and biological enhancer 2;

[0050] The preparation method of biological enhancer 1 is as follows: Mix the concentrated fermentation solutions of Nitrosomonas europaea, Nitrosomonas mesophila, Nitrobacter winogradskyi, Nitrobacter agilis, Pseudomonas aeruginosa, Candida tropicalis, Gloeophyllum trabeum, Streptomyces griseus, and Acinetobacter calcoaceticus according to the mass ratio of 2:1:1:1:1:1:1:1:1 to obtain a strain mixture, and then dilute the strain mixture with sterile water to a strain concentration of 1.5×10 9CFU / mL; Take 50 parts of the strain mixed dilution solution, add 24 parts of the enzyme solution thereto, mix well under sterile conditions, and stir at 28 °C for 2 h to obtain a mixed solution; Add 15 parts of the UIO-66 material to the mixed solution, stir gently to allow the mixed solution to fully infiltrate the UIO-66 material, and then perform ultrasonic oscillation for 4 h to obtain a bio-enhancer precursor; Add 60 parts of the sodium alginate solution to the bio-enhancer precursor, stir evenly and then dropwise add 60 parts of the chitosan solution, continuously stir to form gel microspheres, stir fully at 25 °C for 60 min, and finally transfer to a calcium chloride solution with a concentration of 5% (w / v) and soak for 2 h to form solidified gel microspheres, namely the bio-enhancer intermediate; Wash the bio-enhancer intermediate 3 times with sterile water and dry to obtain the bio-enhancer I; The concentration of the sodium alginate solution is 4% (w / v), and the solvent is water; The concentration of the chitosan solution is 2.5% (w / v), and the solvent is an acetic acid solution with a concentration of 1% (v / v);

[0051] The preparation method of the bio-enhancer II is as follows: Take out the Pseudomonas denitrificans concentrate, and then dilute it with sterile water to a concentration of 1.0×10 9 CFU / mL to obtain a Pseudomonas denitrificans dilution solution; Add 30 parts of the Pseudomonas denitrificans dilution solution, 30 parts of the sodium alginate solution and 30 parts of the chitosan solution thereto, stir evenly and dropwise add to a calcium chloride solution with a concentration of 5% (w / v) and soak for 1.5 h to form gel beads; Wash the gel beads with sterile water and dry to obtain dry gel beads with an average particle size of 4.2 mm, namely the bio-enhancer II;

[0052] Mix concentrated sulfuric acid with a mass fraction of 98% and concentrated nitric acid with a mass fraction of 65% in a volume ratio of 3:1 to prepare a mixed acid solution; Melt dry silica gel spheres with an average particle size of 60 mm and place them in a mold to cool and solidify to obtain a silica gel column with a diameter of 10 cm and a height of 20 cm; Add the silica gel column to the mixed acid solution and perform ultrasonic reaction at 60 °C for 6 h; The solid-liquid ratio is 1:10 (w / v, g / mL); After ultrasonic reaction, dry, and add the acid-treated silica gel column to ammonia water with a mass fraction of 25%, the solid-liquid ratio is 1:10 (w / v, g / mL), perform ultrasonic reaction at 60 °C for 6 h, and then perform suction filtration and dry to obtain an ammoniated silica gel column; Add 300 parts of the ammoniated silica gel column to 1000 parts of a glutaraldehyde solution with a mass concentration of 5%, perform ultrasonic reaction at 30 °C for 2 h, and finally add gel beads and continue ultrasonic reaction for 6 h. After drying, obtain a cured product 31 of the bio-enhancer II and the silica gel column; Vertically fix the cured product at the bottom of the anaerobic pond 3.

[0053] Mixed algae are added to Symbiotic Pond 1, and the mass ratio of Chlorella vulgaris to Spirulina platensis in the mixed algae is 2:3; the addition ratio of the mixed algae to livestock wastewater in Symbiotic Pond 1 is 40 g:1 L; a biological enhancer I is added to Symbiotic Pond 2, and the addition ratio of the biological enhancer I to livestock wastewater in Symbiotic Pond 2 is 50 g:1 L; a biological enhancer II is added to Anaerobic Pond 3, and the addition ratio of the biological enhancer II to livestock wastewater in Anaerobic Pond 3 is 30 g:1 L.

[0054] The preparation method of UIO-66 material is as follows: Add 4.19 parts of zirconium nitrate pentahydrate to 180 parts of dimethylformamide and dissolve to obtain a zirconium nitrate solution; dissolve 1.50 parts of terephthalic acid in 180 parts of dimethylformamide to obtain a terephthalic acid solution; slowly add 1.8 parts of tetrabutyl titanate to 90 parts of dimethylformamide and stir while adding to obtain a tetrabutyl titanate solution; add 0.9 part of indium nitrate hydrate to 90 parts of dimethylformamide and stir to dissolve to obtain an indium nitrate solution; add 1.8 parts of 37% (w / v) hydrochloric acid aqueous solution to the zirconium nitrate solution, and then slowly add the terephthalic acid solution to the above solution and stir evenly to obtain a precursor of the reaction solution; after sequentially adding the tetrabutyl titanate solution and the indium nitrate solution to the precursor of the reaction solution, stir for 60 min to obtain a reaction solution; transfer the reaction solution to a stainless steel reaction kettle lined with polytetrafluoroethylene, seal it and put it into an oven, and react at 140 °C for 48 h to obtain a UIO-66 material precursor; wait for the reaction kettle to cool to room temperature, centrifuge the UIO-66 material precursor, wash the precipitate 3 times with dimethylformamide, and then wash it 3 times with absolute ethanol to displace dimethylformamide to obtain a UIO-66 material intermediate; the UIO-66 material intermediate is vacuum dried at 100 °C for 24 h to obtain the UIO-66 material, and the specific surface area is 1120 m 2 / g;

[0055] The enzyme solution is prepared by mixing cellulase solution, lipase solution, thioesterase solution and protease solution according to a mass ratio of 11:3:4:6; the cellulase solution is activated by mixing cellulase and acetic acid-sodium acetate buffer solution with a pH of 4.5, with a mass concentration of 3.5%, and the enzyme activity after activation is 450 U / mL (high enzyme activity); the lipase solution is activated by mixing lipase and phosphate buffer solution with a pH of 7.0, with a mass concentration of 2.0%, and the enzyme activity after activation is 115 U / mL (medium enzyme activity); the thioesterase solution is activated by mixing thioesterase and Tris-HCl buffer solution with a pH of 7.5, with a mass concentration of 1.0%, and the enzyme activity after activation is 80 U / mL (medium enzyme activity); the protease solution is activated by mixing protease and phosphate buffer solution with a pH of 7.0, with a mass concentration of 1.0%, and the enzyme activity after activation is 530 U / mL (medium enzyme activity).

[0056] Example 2-4

[0057] Different from Example 1, the preparation method of Bioaugmenter 1 and the DO value, pH value and HRT value changed during the first startup of Vertical Aerator 1, as shown in Table 1 specifically.

[0058] Table 1 Preparation of Bioaugmenter 1 and Parameter Adjustment during the First Startup of Vertical Aerator

[0059]

[0060] Example 5

[0061] Different from Example 1, during the first startup of Vertical Aerator 1, the DO value of the aerobic tank was made to be 1.8 mg / L.

[0062] Example 6

[0063] Different from Example 1, during the first startup of Vertical Aerator 1, the DO value of the aerobic tank was made to be 4.0 mg / L.

[0064] Example 7

[0065] Different from Example 1, the HRT value before obtaining the livestock wastewater treated aerobically was 12 h.

[0066] Comparative Example 1

[0067] Different from Example 4, Nitrosomonas europaea and Nitrosomonas mesophila were not added.

[0068] Comparative Example 2

[0069] Different from Example 4, Nitrobacter winogradskyi and Nitrobacter agilis were not added.

[0070] Comparative Example 3

[0071] Different from Example 4, Pseudomonas aeruginosa was not added.

[0072] Comparative Example 4

[0073] Different from Example 4, Candida tropicalis was not added.

[0074] Comparative Example 5

[0075] Different from Example 4, Gloeophyllum trabeum was not added.

[0076] Comparative Example 6

[0077] Different from Example 4, Streptomyces griseus was not added.

[0078] Comparative Example 7

[0079] Different from Example 4, Acinetobacter calcoaceticus was not added.

[0080] Comparative Example 8

[0081] Different from Example 4, the enzyme solution was not added.

[0082] Comparative Example 9

[0083] Different from Example 4, the enzyme activity after activation of the cellulase solution was 200 U / mL.

[0084] Comparative Example 10

[0085] Different from Example 4, the UIO-66 material was not added.

[0086] Comparative Example 11

[0087] Different from Example 4, the UIO-66 material was replaced with a ceramic porous material of equal mass fraction, and the specific surface area was 450 m 2 / g.

[0088] Comparative Example 12

[0089] Different from Example 4, the sodium alginate solution was not added, and the dosage of the chitosan solution was 120 parts.

[0090] Comparative Example 13

[0091] Different from Example 4, the chitosan solution was not added, and the dosage of the sodium alginate solution was 120 parts.

[0092] Experimental Example 1

[0093] The water quality of the above livestock and poultry wastewater based on the biological enhancer was tested, and the test results are shown in Table 2. Referring to GB18596-2001 "Pollutant Discharge Standard for Livestock and Poultry Breeding", among them, the limit values for chemical oxygen demand (COD), ammonia nitrogen and total phosphorus are 400 mg / L, 80 mg / L and 8 mg / L respectively.

[0094] Table 2 Test Results of the Water Quality of Livestock and Poultry Wastewater Based on Biological Enhancers in Examples 1-7 and Comparative Examples 1-14

[0095]

[0096]

[0097] Using the biological synergist I prepared by the present invention and the production process, under the conditions of Examples 1-7, the COD of livestock and poultry wastewater based on the biological synergist was 161-323 mg / L, and the removal rate of COD was 96.6%-98.3%. In Examples 1-4, by adjusting the mass ratio of nine mixed strains and the dosage of the enzyme solution, a mixed solution was obtained; the mixed solution was loaded into the pores of the UIO-66 material, the dosage of the UIO-66 material was adjusted, and the dosages of the sodium alginate solution and chitosan solution for crosslinking were adjusted, so as to obtain a good removal rate of COD; in Example 5, by adjusting the DO value, since the DO value was too low, it was not conducive to the growth of aerobic microorganisms, and the COD removal rate decreased compared with Example 1; compared with Example 1, the DO value in Example 6 increased, resulting in a further increase in the COD removal rate; in Example 7, by adjusting the HRT time, the contact time between the wastewater and the biological synergist I in the aerobic tank was increased, and the removal rate of COD was improved. For Comparative Example 1 and Comparative Example 2, due to the absence of the corresponding strains, the removal effect of organic compounds was reduced, and the COD value decreased compared with Example 4. In Comparative Examples 3-6, Pseudomonas aeruginosa, Candida tropicalis, Gloeophyllum trabeum, and Streptomyces griseus were not added respectively, and the decomposition ability of proteins, fats, carbohydrates, cellulose, hemicellulose, lignin, nitrogen-containing organic compounds, and complex polysaccharides decreased, and thus the COD value increased compared with Example 4. In Comparative Example 7, Acinetobacter calcoaceticus was not added, and the decomposition ability of organic matter also decreased compared with Example 4. In Comparative Example 8, the enzyme solution was not added, and the decomposition ability of cellulose, proteins, and fats decreased, so the COD removal rate decreased compared with Example 4. In Comparative Example 9, the enzyme activity after activation of the cellulase solution was low. Since the pH of the system where the cellulase solution was located was lower than the pH under the process conditions, the enzyme activity was further reduced, and the decomposition ability of organic matter decreased. In Comparative Example 10, the UIO-66 material was not added, and the contact area between the wastewater and the strains decreased, so the removal effect of COD decreased significantly. In Comparative Example 11, the specific surface area of the ceramic porous material was small, and the binding ability between the ceramic porous material and the strains was weak, so the removal effect of organic matter was also poor. In Comparative Examples 12 and 13, only the chitosan solution or sodium alginate solution was added, and the COD removal rate decreased compared with the examples.

[0098] Examples 8-11

[0099] Different from Example 4, the lighting conditions and process conditions in the symbiotic pond and the preparation method of the UIO-66 material were changed, as shown in Table 3 specifically.

[0100] Example 12

[0101] Different from Example 4, the addition ratio of the mixed algae and livestock and poultry wastewater in the symbiotic pond was 50 g:1 L.

[0102] Example 13

[0103] Different from Example 4, the addition ratio of mixed algae and livestock wastewater in the symbiotic pond is 30 g: 1 L.

[0104] Example 14

[0105] Different from Example 4, the addition ratio of Bioaugmentation Agent I and livestock wastewater in the aerobic pond is 20 g: 1 L.

[0106] Example 15

[0107] Different from Example 4, the addition ratio of Bioaugmentation Agent I and livestock wastewater in the aerobic pond is 60 g: 1 L.

[0108] Comparative Example 14

[0109] Different from Example 4, when the wastewater first enters the symbiotic pond, the lighting stops after 1 h and resumes after 2 h.

[0110] Comparative Example 15

[0111] Different from Example 4, the DO value of the refluxed symbiotic pond is 1.0 mg / L.

[0112] Comparative Example 16

[0113] Different from Example 4, aeration and lighting are carried out simultaneously.

[0114] Comparative Example 17

[0115] Different from Example 4, indium nitrate hydrate is not added during the preparation of the UIO-66 material.

[0116] Comparative Example 18

[0117] Different from Example 4, tetrabutyl titanate is not added during the preparation of the UIO-66 material.

[0118] Comparative Example 19

[0119] Different from Example 4, neither tetrabutyl titanate nor indium nitrate hydrate is added during the preparation of the UIO-66 material.

[0120] Table 3 Lighting conditions and preparation method of UIO-66 material

[0121]

[0122]

[0123] Experimental Example 2

[0124] COD tests were conducted on the livestock and poultry wastewater based on bioaugmenters obtained in Example 4, Examples 8 - 15, and Comparative Examples 14 - 19, and the final test results are shown in Table 4.

[0125] Table 4 Wastewater COD Results of Example 4, Examples 8 - 15, and Comparative Examples 14 - 19

[0126] COD (mg / L) Removal rate (%) COD (mg / L) Removal rate (%) Example 4 161 98.3 Example 15 173 98.2 Example 8 169 98.2 Comparative Example 14 378 96.0 Example 9 213 97.8 Comparative Example 15 462 95.1 Example 10 176 98.1 Comparative Example 16 524 94.5 Example 11 150 98.4 Comparative Example 17 339 96.4 Example 12 173 98.2 Comparative Example 18 321 96.6 Example 13 227 97.6 Comparative Example 19 455 95.2 Example 14 185 98.0

[0127] For the livestock and poultry wastewater based on bioaugmenters obtained in the present invention, under the conditions of Example 4, Examples 8 - 15, the COD value is 150 - 227 mg / L, and the removal rate of COD is 97.6% - 98.4%. In Example 4 and Examples 8 - 11, by optimizing the preparation method of the UIO - 66 material, adjusting the light exposure time and light when the wastewater first enters the symbiotic pond, adjusting the DO value of the symbiotic pond after the first reflux, setting the alternating mode of exposure and aeration, and adjusting the respective hydraulic retention time (HRT) values, the removal effect of COD under the production process conditions is increased. By adding tetrabutyl titanate and indium nitrate hydrate during the preparation process of the UIO - 66 material, the embedded titanium and indium atoms increase the light absorption coefficient of the material, enabling the material to more effectively absorb photon energy, generating more photogenerated electron - hole pairs, providing more active species for the subsequent redox reaction; improving the electron conduction performance of the material, promoting the transport of photogenerated carriers, and enabling the photogenerated electrons to migrate to the surface of the material more quickly to react with the organic pollutants adsorbed on the surface, thus improving the reaction rate and efficiency. Loading the strain on the surface of the UIO - 66 material to obtain Bioaugmenter 1. Under light conditions, on the basis of the original algae decomposing organic matter, Bioaugmenter 1 also decomposes organic matter, promoting the degradation of organic matter. Not adding any one of the above substances in Comparative Examples 17 and 18 will result in a decrease in the removal rate of COD; not adding the above two substances in Comparative Example 19 greatly reduces the removal effect of COD. In Examples 12 - 15, by adjusting the addition ratios of the mixed algae and livestock and poultry wastewater in the symbiotic pond and the addition ratios of Bioaugmenter 1 and livestock and poultry wastewater in the aerobic pond, there are sufficient amounts of algae and microorganisms to act on the wastewater. In Comparative Example 14, due to the relatively short single - stage light exposure time, it is not conducive to the degradation and removal of organic matter by algae and Bioaugmenter 1, and the COD value is greatly reduced. The DO value of the refluxed symbiotic pond in Comparative Example 15 is 1.0 mg / L, which is not conducive to the growth of aerobic bacteria, thus reducing the removal effect of COD. In Comparative Example 16, aeration and light exposure are carried out simultaneously, with too long exposure time and too long aeration time. Too long exposure time damages the loaded strain, thus being not conducive to COD removal.

[0128] Examples 16 - 18

[0129] Different from Example 11, the preparation method of biological enhancer II, the addition amount in the anaerobic tank, and the DO value and reaction time after the three-stage aerated livestock wastewater enters the anaerobic tank through pipeline 4 are changed, as shown in Table 5 specifically. The ultrasonic temperature in Table 5 is the temperature after adding the glutaraldehyde solution; the ultrasonic time is the time after adding the gel beads. HRT is the HRT value when the three-stage aerated livestock wastewater first enters the anaerobic tank through pipeline 4. The ratio between the two is the addition ratio of biological enhancer II and livestock wastewater.

[0130] Table 5 Production process related to biological enhancer II

[0131]

[0132] Comparative Example 20

[0133] Different from Example 11, the dilution concentration of the Pseudomonas denitrificans concentrate is 1.0×10 7 .

[0134] Comparative Example 21

[0135] Different from Example 11, the ultrasonic temperature is 40 °C and the ultrasonic time is 2.0 h.

[0136] Comparative Example 22

[0137] Different from Example 11, the silica gel column is not ammoniated.

[0138] Comparative Example 23

[0139] Different from Example 11, biological enhancer II is directly added to the anaerobic tank.

[0140] Comparative Example 24

[0141] Different from Example 11, HRT is 7 d.

[0142] Comparative Example 25

[0143] Pseudomonas denitrificans is not added during the preparation process of biological enhancer I.

[0144] Experimental Example 3

[0145] The wastewater treated by the above processes is tested for ammonia nitrogen and total phosphorus (calculated as P), and the final test results are shown in Table 6.

[0146] Table 6 Test results of ammonia nitrogen and total phosphorus for Examples 11, 16 - 18 and Comparative Examples 20 - 26

[0147]

[0148] The livestock and poultry wastewater based on the biological enhancer has an ammonia nitrogen removal rate of 84.0%-85.7% and a total phosphorus removal rate of 75.4%-77.7% under the conditions of Examples 11 and 16-18. In the above examples, by adjusting the concentration of the bacterial solution in the preparation process of the biological enhancer II and optimizing the addition ratio of the biological enhancer II in the anaerobic tank, sufficient and appropriate Pseudomonas denitrificans can react in the anaerobic stage; by adjusting the dosage of the Pseudomonas denitrificans dilution solution, forming microspheres with the sodium alginate solution and the chitosan solution, and then ammoniating the silica gel column, the biological enhancer II is chemically bonded to the silica gel column. By controlling the temperature and time of ultrasound, after the biological enhancer II is solidified with the ammoniated silica gel column, it stably exists in the anaerobic tank, avoiding interference with other systems and the loss of anaerobic bacteria during the reflux process, thus avoiding an increase in production costs. By adjusting the HRT value of the livestock and poultry wastewater with three-stage aeration entering the anaerobic tank for the first time through pipeline four, good removal of ammonia nitrogen substances is achieved. In Comparative Example 1 and Comparative Example 2, Nitrosomonas and Nitrobacter are not added to the biological enhancer I respectively, and the nitrification process cannot proceed smoothly, resulting in a decrease in the ammonia nitrogen removal effect; however, it has little impact on the removal of total phosphorus. In Comparative Example 7, Acinetobacter calcoaceticus is not added to the biological enhancer I, and the system lacks strains for phosphorus absorption and degradation, resulting in a decrease in the total phosphorus removal effect compared to Example 11. In Comparative Example 20, the dilution concentration is too low, which is not conducive to the growth of denitrifying bacteria and the nitrification process, thus resulting in a decrease in the ammonia nitrogen removal effect. In Comparative Example 21, the ultrasound temperature is too high, the growth activity of denitrifying bacteria decreases, and the ammonia nitrogen removal effect decreases significantly, but it has little impact on the removal of total phosphorus. In Comparative Example 22, the silica gel column is not ammoniated, the binding force between the silica gel column and the biological enhancer II decreases, anaerobic bacteria are lost when the wastewater flows back from the anaerobic tank to the aerobic tank, and a large number of anaerobic bacteria die in the aerobic tank, and the substances produced have an adverse effect on the production of aerobic bacteria, resulting in a decrease in the removal rates of both ammonia nitrogen and total phosphorus. In Comparative Example 23, the biological enhancer II is directly added to the anaerobic tank, resulting in a further decrease in the removal effects of ammonia nitrogen and total phosphorus. In Comparative Example 24, the HRT value is too high, and microorganisms are in an environment with a low substrate concentration for a long time, which will lead to a slowdown in their metabolic rate; it will cause the sludge to stay in the anaerobic tank for too long and age, and the microorganisms in the sludge will produce some gases, such as nitrogen, carbon dioxide, etc.; these gases adhere to the sludge, which will reduce the specific gravity of the sludge and cause the sludge to float. The floating of the sludge will not only affect the normal operation of the anaerobic tank, so the ammonia nitrogen removal effect is greatly reduced. The ammonia nitrogen removal is greatly affected under the conditions of Comparative Example 25.

[0149] Comparative Example 26

[0150] Different from Example 18, the livestock and poultry wastewater treated aerobically does not flow back to the symbiotic pond through the air stripper in pipeline three, but directly enters the anaerobic tank through pipeline four.

[0151] Comparative Example 27

[0152] Different from Example 18, after the three-stage aerated livestock and poultry wastewater enters the anaerobic tank through Pipeline 4, it directly enters the electrode electro-Fenton reactor through Pipeline 6 for treatment.

[0153] Comparative Example 28

[0154] Different from Example 18, the oxygen-treated livestock and poultry wastewater does not flow back to the symbiotic tank through the air stripper in Pipeline 3, but directly enters the anaerobic tank through Pipeline 4, and after the wastewater enters the anaerobic tank through Pipeline 4, it directly enters the electrode electro-Fenton reactor through Pipeline 6 for treatment.

[0155] Comparative Example 29

[0156] Different from Example 18, after the livestock and poultry wastewater flows back to the symbiotic tank through the air stripper in Pipeline 3, it enters the aerobic tank, and then flows back to the symbiotic tank through the air stripper in Pipeline 3 again.

[0157] Comparative Example 30

[0158] Different from Example 18, after the livestock and poultry wastewater flows back to the aerobic tank through Pipeline 5, it enters the anaerobic tank through Pipeline 4, then flows back to the aerobic tank through Pipeline 5 again, and after being treated in the anaerobic tank through Pipeline 4, it enters the electrode electro-Fenton reactor through Pipeline 6 for treatment.

[0159] Comparative Example 31

[0160] Different from Example 18, after the livestock and poultry wastewater flows back to the symbiotic tank through the air stripper in Pipeline 3, it enters the aerobic tank, and then flows back to the symbiotic tank through the air stripper in Pipeline 3 again. And after the livestock and poultry wastewater flows back to the aerobic tank through Pipeline 5, it enters the anaerobic tank through Pipeline 4, then flows back to the aerobic tank through Pipeline 5 again, and after being treated in the anaerobic tank through Pipeline 4, it enters the electrode electro-Fenton reactor through Pipeline 6 for treatment.

[0161] Comparative Example 32

[0162] Different from Example 18, the ultrasonic generator is not started.

[0163] Comparative Example 33

[0164] Different from Example 18, it does not undergo co-treatment by the electrode electro-Fenton reactor and ultrasound.

[0165] Experimental Example 4

[0166] The livestock and poultry wastewater based on the biological enhancer prepared in Comparative Examples 26 - 33 was subjected to water quality detection, and the final detection results are shown in Table 7.

[0167] Table 7 Wastewater treatment water quality of Example 18 and Comparative Examples 26 - 33

[0168]

[0169] Under the process conditions of Example 18 of the present invention, the removal rates of COD, ammonia nitrogen and total phosphorus are 98.5%, 85.7% and 77.7% respectively. In Comparative Example 26 and Comparative Example 27, the wastewater did not undergo reflux treatment when passing through the aerobic tank and anaerobic tank respectively. First of all, the contact time between the wastewater and algae, aerobic microorganisms and anaerobic microorganisms became shorter, and the removal effects of organic compounds, ammonia nitrogen and total phosphorus in the wastewater decreased. For Comparative Example 28, the wastewater only passed through the symbiotic tank, aerobic tank, anaerobic tank and the ultrasonic-based electrode electro-Fenton reactor in sequence, and the removal effects of the above substances further decreased. Comparative Example 29 and Comparative Example 30 carried out secondary reflux respectively, but the removal effects of the above three substances were basically the same as those of Example 18. Comparative Example 31 underwent multiple rounds of reflux, and the removal rates of COD, ammonia nitrogen and total phosphorus increased, but the increase was not obvious, and the treatment time was increased, the treatment efficiency was reduced, and greater losses were caused to strains, electricity and materials, etc. In Comparative Example 32, the ultrasonic generator was not started, and the treatment effect decreased. After ultrasonic treatment, cavitation effect will be generated when ultrasonic propagates in the liquid, that is, tiny bubbles are formed and quickly collapse. At the moment when the bubbles collapse, extreme conditions of high temperature (up to 5000K) and high pressure (up to 1000atm) will be generated, causing the water molecules to be cleaved to produce strongly oxidizing hydroxyl radicals (·OH), which can further remove substances such as antibiotics in the water body; the mechanical vibration effect of ultrasonic can cause strong stirring and mixing effects on the wastewater, promote the uniform distribution of various substances in the electrode electro-Fenton reaction system, and in the treatment of livestock wastewater, make the active substances on the electrode surface better contact with antibiotics and accelerate the reaction rate. In Comparative Example 33, the wastewater was not co-treated by the electrode electro-Fenton reactor and ultrasonic, and the removal rates of COD, ammonia nitrogen and total phosphorus were lower than those of Example 18. The co-treatment of the electrode electro-Fenton reactor and ultrasonic achieved a further removal effect on the organic matter in the wastewater.

[0170] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A livestock wastewater treatment process based on bio-enhancer, characterized in that: The processing technology is as follows: The S1 wastewater enters the symbiosis pool (1) through pipeline 1, and is illuminated at 5000-7000 lux for 2.5-4.5 hours, then stops, and is illuminated intermittently until the symbiosis pool (1) is treated for 5-7.5 days, and the algae-treated wastewater is then entered into the aerobic pool (2); S2 starts the vertical aerator 1 (21), the DO value is 1.8-4.0 mg / L, the HRT value is 10-12h, the treated wastewater flows back to the symbiotic pond (1) through the air stripper (22) of the pipeline 3, starts the vertical aerator 2 (11), so that the DO value of the symbiotic pond (1) is 1.8-3.5 mg / L, and after aeration for 2.5-4.5 hours, it is illuminated, and 7000 lux is irradiated for 3.5-5.0 hours. Aeration and illumination are performed alternately until the symbiotic pond (1) is treated for 3.5-5 days, and the obtained second-stage illumination wastewater enters the aerobic pond (2) again through the pipeline 2; S3: start the vertical aerator 1 (21), and the three-stage aerated wastewater obtained by the treatment enters the anaerobic tank (3) through the pipeline 4, and after fully reacting for HRT 2.5-4d, it flows back into the aerobic tank (2) through the air stripper (32) of the pipeline 5; S4 starts the vertical aerator 1 (21), and the obtained four-stage aerated wastewater enters the anaerobic tank (3) through the pipeline 4 for the second time, and flows out through the pipeline 6 after treatment. The obtained secondary anaerobic treatment wastewater is passed into the three-dimensional particle electrode electro-Fenton reactor (4) equipped with an ultrasonic transducer to obtain the poultry and livestock wastewater based on the bio-enhancer.

2. The process for treating livestock wastewater based on bio-enhancer according to claim 1, characterized in that: The mixed algae in the symbiotic pond (1), the biological enhancer 1 in the aerobic pond (2) and the biological enhancer 2 in the anaerobic pond (3) are added to the livestock wastewater in a ratio of 30-50 g:1 L, 20-60 g:1 L and 10-45 g:1 L respectively.

3. A livestock wastewater treatment process based on bio-enhancer according to claim 2, characterized in that: The preparation method of the biological enhancer 1 is as follows: European Nitrosomonas, mesophilic Nitrosomonas, Nitrobacter versicanus, Nitrobacter active, Pseudomonas aeruginosa, Candida tropicalis, Glehnia littoralis, Streptomyces griseus and Acinetobacter calcoaceticus fermentation strain concentrates are mixed in a mass ratio of 1-3:1-3:1-4:1-3:1:1-2:1-2:1-2:1 to obtain a strain mixture, and the mixture is diluted to obtain a strain mixture dilution; 24-26 parts of enzyme solution are added to the mixed dilution of the strains, and the mixture is mixed to obtain a mixed solution; 15-25 parts of UIO-66 material are added to the mixed solution, and the mixture is stirred and ultrasonically oscillated to obtain a biosynergist precursor; 45-70 parts of sodium alginate solution are added to the biosynergist precursor, and 50-60 parts of chitosan solution are added dropwise after stirring evenly, and the mixture is continuously stirred to form gel microspheres, and after stirring, the microspheres are transferred to a calcium chloride solution for immersion, rinsed with sterile water, and dried to obtain the biosynergist precursor.

4. A livestock wastewater treatment process based on bio-enhancer according to claim 2, characterized in that: The preparation method of the biological enhancer 2 is as follows: sodium alginate solution and chitosan solution are added to 26-35 parts of denitrifying Pseudomonas dilution, stirred evenly, and then soaked in calcium chloride solution, washed gel beads and dried to obtain the biological enhancer 2; the concentration of the nitrogen Pseudomonas dilution is 0.8×10 9 -1.2×10 9 CFU / mL.

5. The process for treating livestock wastewater based on bio-enhancer according to claim 1, characterized in that: Concentrated sulfuric acid and concentrated nitric acid are mixed in a volume ratio of 3:1 to prepare a mixed acid solution; dry silica gel balls are melted and placed in a mold for cooling and solidification to obtain a silica gel column with a diameter of 10 cm and a height of 20 cm; the silica gel column is added to the mixed acid solution, dried after ultrasonic reaction, and the acid-treated silica gel column is added to ammonia water, filtered after ultrasonic reaction, and dried to obtain an ammoniated silica gel column; 290-320 parts of the ammoniated silica gel column are added to glutaraldehyde solution, ultrasonically reacted at 25-30°C for 2h, and finally a biosynergist 2 is added, and ultrasonication is continued for 5-9h. After drying, a solidified product (31) of the biosynergist 2 and the silica gel column is obtained; and the solidified product is vertically fixed at the bottom of an anaerobic tank (3).

6. The process for treating livestock wastewater based on bio-enhancer according to claim 3, characterized in that: The enzyme solution is prepared by mixing a cellulase solution, a lipase solution, a thioesterase solution and a protease solution in a mass ratio of 8-11:3-7:3-6:4-7.

7. The process for treating livestock wastewater based on bio-enhancer according to claim 3, characterized in that: The preparation method of the UIO-66 material is as follows: 1.5-2.0 parts of tetrabutyl titanate are slowly added dropwise to 90 parts of dimethylformamide, and stirred while adding dropwise to obtain a tetrabutyl titanate solution; 0.4-0.9 parts of indium nitrate hydrate are added to 90 parts of dimethylformamide, and stirred to dissolve to obtain an indium nitrate solution; 1.8 parts of hydrochloric acid aqueous solution are added to the zirconium nitrate solution, and then a terephthalic acid solution is added, and stirred evenly to obtain a liquid precursor to be reacted; The tetrabutyl titanate solution and the indium nitrate solution are slowly added to the reaction liquid precursor in sequence, and stirred for 60 minutes to obtain the reaction liquid; the reaction liquid is transferred to a stainless steel reactor lined with polytetrafluoroethylene, sealed and placed in an oven, and reacted at 140°C for 48 hours to obtain a UIO-66 material precursor; then cooled, centrifuged and washed to obtain a UIO-66 material intermediate; the UIO-66 material intermediate is vacuum dried at 100°C for 24 hours to obtain a UIO-66 material.

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