A kind of odor-removing and denitrifying bacteria and its application in composite intelligent water purification

Abstract

The present invention belongs to the technical field of deep treatment and resource utilization of aquaculture tail water, and specifically relates to a deodorizing and denitrifying bacterium and its application in composite intelligent water purification. The deodorizing and denitrifying bacterium is Glutamicibacter sp. YTLJ-N-S7. The deodorizing and denitrifying bacterial strain and its bacterial agent of the present invention are obtained by pre-culturing and propagating Glutamicibacter sp. YTLJ-N-S7 obtained by screening, and then obtaining the corresponding single-bacterium powder through vacuum freeze-drying. The single-bacterium powder is mixed and assembled with Enterococcus sp. YTLJ-N-SXH1 / nitrifying bacteria, and then mixed with an auxiliary agent to prepare. The deodorizing and denitrifying bacterial agent is added to the aquaculture system, and part of the tail water to be treated flows through the externally connected deodorizing and denitrifying equipment system for treatment. After treatment, the aquaculture tail water is recycled after regeneration.

Description

Technical Field

[0001] The invention belongs to the technical field of deep treatment and resource utilization of aquaculture tail water, and particularly relates to an odor-removing denitrifying bacterium and its application in composite intelligent water purification. Background Art

[0002] Problems such as water environmental pollution and frequent occurrence of aquatic diseases caused by large-scale high-density aquaculture seriously trouble the development of the aquaculture industry. At present, there are few water treatment recycling technologies for high-density aquaculture systems, the treatment cost is relatively high, the nitrogen removal effect is average, and the accumulation of odor substances is likely to occur, which greatly limits the popularization and application of the recirculating aquaculture technology.

[0003] In recent years, the in-situ water purification technology based on biofloc aquaculture has been applied to a certain extent in the aquaculture industry. This technology can not only achieve the rapid conversion of ammonia nitrogen in the aquaculture pond, play a role in purifying water quality, but also serve as a high-protein bait for feeding aquatic animals, thereby reducing the feed cost. Through retrieving the prior art, it is found that Deng Yingneng et al. mentioned in the article "Formation conditions and effect of bioflocs in the closed culture experiment of Litopenaeus vannamei" that by introducing the biofloc technology into the closed culture system of Litopenaeus vannamei, the concentrations of ammonia nitrogen and nitrite nitrogen in the water body are maintained at a relatively low level, and the survival rate of Litopenaeus vannamei is above 80% (Progress in Fishery Sciences, 2012, 33(2): 69-75); Li Bin et al. mentioned in the article "Effect of bioflocs on water quality regulation and growth of juvenile Apostichopus japonicus" that the bioflocs formed by adding carbon sources and Bacillus can not only purify water quality, but also promote the growth of juvenile Apostichopus japonicus (Progress in Fishery Sciences, 2014, 46(1): 197-205). However, the above technologies all use a large amount of additional organic carbon sources as exogenous substances to promote the generation of organic nitrogen through assimilation of ammonia nitrogen. The biofloc production in the aquaculture system is high and the oxygen consumption is high. At the same time, the long-term accumulation of feces and residual baits in the aquaculture system is more likely to cause the accumulation of odor substances, thus affecting the quality of aquatic products. These disadvantages limit the popularization and application of high-density aquaculture technologies. Summary of the Invention

[0004] The purpose of the invention is to provide an odor-removing denitrifying bacterium and its application in composite intelligent water purification in view of the deficiencies of the prior art.

[0005] To achieve the above purpose, the technical solution adopted by the invention is as follows:

[0006] The odor-removing and denitrifying bacterium is Glutamicibacter sp. YTLJ-N-S7, which was deposited in the Guangdong Microbial Culture Collection Center on May 26, 2021, with the deposit number GDMCC No: 61694, the taxonomic name Glutamicibacter sp., and the deposit address in Guangzhou, China.

[0007] The application of Glutamicibacter sp. YTLJ-N-S7 in purifying water, removing odor, and denitrifying.

[0008] A water-purifying, odor-removing, and denitrifying bactericide, the bactericide containing the Glutamicibacter sp. YTLJ-N-S7 described above.

[0009] The bactericide is one or more of Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, or nitrifying bacteria. The Enterococcus sp. YTLJ-N-SXH1 was deposited in the Guangdong Microbial Culture Collection Center on November 26, 2021, with the deposit number GDMCC No: 62080, the taxonomic name Enterococcus sp., and the deposit address in Guangzhou, China.

[0010] The Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria are respectively propagated and dried to obtain the dry powders of each strain. Then, the dry powder of Glutamicibacter sp. YTLJ-N-S7 after propagation and the dry powder of Enterococcus sp. YTLJ-N-SXH1 are mixed according to a mass ratio of 1-10:1 to obtain powder A;

[0011] The dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of nitrifying bacteria are mixed according to a mass ratio of 1-10:1 to obtain powder B;

[0012] The above-mentioned powder A and powder B are respectively mixed with an auxiliary agent according to a mass ratio of 1:1-100 to obtain each bactericide, and the total effective viable count of each bactericide ≥ 1.0×10 9 CFU / mL;

[0013] Or, the mixtures obtained by mixing the powder A and powder B with the auxiliary agent respectively are further mixed to obtain the bactericide.

[0014] The auxiliary agent is prepared by mixing the disinfected residual aquaculture feces, wheat bran, soybean meal, and bagasse in a mass mixing ratio of 1:1:1:1; after mixing, 0.1% - 1.0% of the dried powder of Glutamicibacter sp. YTLJ-N-S7 after propagation based on the mass of the mixture (the mixture of disinfected residual aquaculture feces, wheat bran, soybean meal, and bagasse) is added, and then 0.05% - 0.5% of mixture A based on its mass is added. After mixing evenly, the water content of the reaction system is controlled to be 40% - 80%, and then fermentation is carried out. The fermented product is collected and polyglutamic acid accounting for 0.5 - 1.0% of the mass of the fermented product is added to prepare the auxiliary agent; wherein mixture A is a mixture of NH4NO3 and glutamic acid in a mass ratio of 1:1 - 5.

[0015] An application of the bacterial agent, the application of the bacterial agent in water purification, odor removal, and denitrification.

[0016] The application of the bacterial agent in comprehensively and intelligently treating the water inside and outside the aquaculture pond, removing odor, and denitrifying.

[0017] The comprehensive and intelligent treatment of the water inside and outside the aquaculture pond refers to using the bacterial agent obtained by mixing bacterial powder A and the auxiliary agent to treat the in-situ internal circulating water of the aquaculture pond; using the bacterial agent obtained by mixing bacterial powder B and the auxiliary agent to treat the external circulating tail water connected to the aquaculture pond.

[0018] For the treatment, odor removal, and denitrification of the in-situ internal circulating water of the aquaculture pond, the inoculation amount of the bacterial agent is 1.0 - 10.0 g / m 2 ;

[0019] For the treatment, odor removal, and denitrification of the external circulating tail water connected to the aquaculture pond, the inoculation amount of the bacterial agent is 0.1 - 1.0 g / m 2 。

[0020] During the treatment, odor removal, and denitrification of the in-situ internal circulating water of the aquaculture pond, a temperature, dissolved oxygen, and pH intelligent control system is installed inside the aquaculture pond. The dissolved oxygen controlled by the system is not less than 5 mg / L, and the pH value is not less than 6.5 and not higher than 8.5, ensuring that the internal circulation system is within the suitable environment range for the growth of aquaculture organisms and the water purification of the bacterial agent.

[0021] During the treatment, odor removal, and denitrification of the external circulating tail water connected to the aquaculture pond, a dissolved oxygen and pH intelligent control system is installed outside the aquaculture pond. When the dissolved oxygen in the tail water is higher than 5 mg / L, aeration is stopped, and the pH value is not less than 6.0 and not higher than 9.0. Ensure that the external circulation system is within the suitable environment range for the water purification of the bacterial agent.

[0022] An electrocoagulation or microfiltration device is also installed at the front end of the external circulating tail water odor removal and denitrification reuse system (external circulation system), and an ozone or ultraviolet disinfection system is installed at the end.

[0023] The advantages of the present invention are:

[0024] Functionally compound probiotics with denitrification, odor removal and pathogen inhibition functions to achieve the integration of denitrification, disinfection and deodorization functions. Specifically:

[0025] 1) Glutamicibacter sp. YTLJ-N-S7 used in the present invention has the dual functions of odor removal and denitrification while denitrifying biologically, compared with ordinary organisms.

[0026] 2) Mixing Glutamicibacter sp. YTLJ-N-S7 of the present invention with ordinary nitrifying bacteria can achieve complementary advantages in the nitrogen metabolism pathway, which is beneficial to improving the denitrification efficiency and shock resistance of the system. The special denitrification pathway of Glutamicibacter sp. YTLJ-N-S7 of the present invention is completely different from the pathway of ordinary nitrifying bacteria from ammonia nitrogen to nitrate. It has the special functions of heterotrophic short-cut nitrification and denitrification-aerobic denitrification. It can convert ammonia nitrogen in wastewater into hydroxylamine through heterotrophic short-cut nitrification and denitrification and then quickly generate nitrogen for removal, reducing the production of highly toxic nitrite. At the same time, it can completely remove nitrite and nitrate from the aquaculture water in the form of nitrogen under aerobic conditions through aerobic denitrification, further avoiding the accumulation problem of nitrite and nitrate in the system.

[0027] 3) The present invention uses special new strains that can produce glutamic acid, which has the effect of enhancing freshness and improving the palatability of bait, increasing the feeding rate of aquaculture animals, saving feed, realizing the recycling of bait, and being able to ecologically and friendly solve the problem of retention of feces and residual bait in the aquaculture water, reducing environmental pollution.

[0028] 4) Glutamicibacter sp. YTLJ-N-S7 of the present invention can form a mutually beneficial symbiotic relationship with Enterococcus sp. YTLJ-N-SXH1 in the aquaculture system and aquaculture organisms, inhibit pathogens and promote the proliferation of Glutamicibacter sp. YTLJ-N-S7 in the intestine and feces, achieving the effect of in-situ degradation of odor substances and deodorization, ensuring the simple operability of in-situ treatment and purification of aquaculture water, and at the same time enhancing the immunity of aquaculture organisms.

[0029] 5) Glutamicibacter sp. YTLJ-N-S7 of the present invention is intelligently assembled with other functional strains to create a specific water purification bactericide suitable for the internal and external double circulation system. Description of the Drawings

[0030] Figure 1This is a cluster analysis diagram of Glutamicibacter sp. YTLJ-N-S7 provided by the embodiments of the present invention and other strains of the same genus.

[0031] Figure 2 This is the structure diagram of the aquaculture pond provided by the embodiments of the present invention. Detailed implementation manners

[0032] The present invention will be further described below through embodiments. However, the present invention is not limited to the following embodiments.

[0033] The nitrifying bacteria mentioned in the following embodiments are commercially available strains. Embodiment 1

[0034] Isolation of Glutamicibacter sp. YTLJ-N-S7:

[0035] The Glutamicibacter sp. YTLJ-N-S7 was isolated from the coastal zone environment. The specific isolation process is as follows: Take 10 g of water sample and place it in 50 mL of sterilized water, keep it at a constant temperature of 25 °C and shake it for 48 h. After centrifuging the bacterial liquid at 8000 rpm for 10 min, remove the supernatant. Transfer the lower-layer bacterial liquid to a sterilized enrichment medium and culture it at 30 °C for 7 days. Then, perform dilution culture in LB medium, select single colonies and perform streak isolation on agar solid medium to obtain the purified strain Glutamicibacter sp. YTLJ-N-S7.

[0036] The enrichment medium used is 0.08% NH4NO3, 0.05% NH4NO2, 0.2% sodium acetate, 0.1% glutamic acid, 3% K2HPO4, 1% MgSO4, 2% NaCl, 0.03% FeSO4, 0.02% MnSO4, geosmin (100 μg / L) and 2-methylisoborneol (100 μg / L) by mass ratio.

[0037] The Glutamicibacter sp. YTLJ-N-S7 was deposited at the Guangdong Provincial Microbial Culture Collection Center on May 26, 2021, with the deposit number GDMCC No: 61694, and the taxonomic name is Glutamicibacter sp., and the deposit address is Guangzhou, China.

[0038] It was confirmed that Glutamicibacter sp. YTLJ-N-S7 is a newly discovered strain by comparing the 16S rDNA gene sequences.

[0039] The 16S rDNA gene sequence of the Glutamicibacter sp. YTLJ-N-S7 is as follows:

[0040] Example 2

[0041] Application of the obtained Glutamicibacter sp. YTLJ-N-S7 in the water purification system:

[0042] Cultivate Glutamicibacter sp. YTLJ-N-S7 pure bacteria in an enrichment medium at 30 °C until OD 600 ≥1.0, and then inoculate the bacterial liquid into the simulated wastewater at an inoculation amount of 10 wt%. The wastewater is the effluent of a sewage treatment plant added with ammonia nitrogen, nitrite, nitrate, geosmin, and glucose. The concentrations of ammonia nitrogen, nitrite, and nitrate nitrogen are 1, 0.5, and 50 mg / L respectively, the concentrations of the odor substances geosmin and 2-methylisoborneol are both 100 ng / L, and the glucose concentration is 200 mg / L.

[0043] After inoculating the bacterial liquid, perform aerobic treatment at 25 °C for 48 h. The concentrations of ammonia nitrogen, nitrite, and nitrate nitrogen are reduced to 0.02, 0.01, and 1 mg / L respectively, geosmin and 2-methylisoborneol are both lower than 10 ng / L, and glucose is lower than 1 mg / L; at the same time, 1 mg / L of glutamic acid and 0.02 mg / L of hydroxylamine are produced.

[0044] Compared with ordinary nitrifying bacteria, Glutamicibacter sp. YTLJ-N-S7 exhibits the functions of heterotrophic short-cut nitrification and aerobic denitrification. The consumption of the organic carbon source (glucose) and the production of hydroxylamine confirm the occurrence of heterotrophic short-cut nitrification by Glutamicibacter sp. YTLJ-N-S7. The removal of nitrate under aerobic conditions confirms the occurrence of aerobic denitrification by Glutamicibacter sp. YTLJ-N-S7. At the same time, Glutamicibacter sp. YTLJ-N-S7 overcomes the disadvantage that ordinary denitrifying bacteria cannot remove ammonia nitrogen and realizes the removal of ammonia nitrogen. Example 3

[0045] Advanced treatment and recycling of aquaculture water during the eel farming process in a coastal area:

[0046] 1) Preparation method of the odor-removing and nitrogen-removing bacterial agent

[0047] a) Strain propagation: Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1 and nitrifying bacteria were respectively inoculated into the propagation medium at an inoculation amount of 5 wt%, and cultured at 30 °C for 24 hours. After the culture time ended, the bacteria were collected for use. The medium for strain propagation was, by mass percentage, glutamic acid (0.02%), glucose (0.02%), and the balance was water.

[0048] The nitrifying bacteria were purchased from Huachu Company. Enterococcus sp. YTLJ-N-SXH1 was preserved in the Guangdong Microbial Culture Collection Center on November 26, 2021, with the preservation number GDMCC No: 62080, the taxonomic name Enterococcus sp., and the preservation address in Guangzhou, China.

[0049] b) Preparation of mixed bacterial powder: The bacterial solutions of Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria obtained by the above separate propagation were respectively freeze-dried (-20 °C pre-cooling for 2 h, -50 °C freeze-drying for 6 h) to obtain dry powders of single strains.

[0050] Then, the dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of Enterococcus sp. YTLJ-N-SXH1 were mixed in a ratio of 1:1 to prepare an internal circulation type odor-removing and denitrifying mixed bacterial powder; the dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of nitrifying bacteria were mixed in a ratio of 1:1 to prepare an external circulation type odor-removing and denitrifying mixed bacterial powder.

[0051] c) Preparation of additives: Take the breeding feces and residual bait (in this example, obtained from breeding eels), disinfect them with potassium bisulfate in a conventional manner, and then mix them with wheat bran, soybean meal, and bagasse. The mass mixing ratio of the disinfected feces and residual bait, wheat bran, soybean meal, and bagasse is 1:1:1:1. After mixing, 0.1% (by mass) of the dry powder of Glutamicibacter sp. YTLJ-N-S7 propagated according to the above steps and 0.05% (by mass) of the mixture were added to the system. After mixing evenly, the water content of the reaction system was controlled to be 40%, and then fermentation was carried out (fermentation conditions: 35 °C for 5 days). After the fermentation ended, the fermentation product was collected, dried, and 0.5% of polyglutamic acid based on the mass of the fermentation product was added to prepare the additive.

[0052] Among them, NH4NO3 and glutamic acid in the mixture were mixed in a mass ratio of 1:1.

[0053] d) Preparation of bacterial agent: The inner - cycle mixed bacterial powder or outer - cycle mixed bacterial powder obtained in step b is respectively mixed with the auxiliary agent obtained in step c at a ratio of 1:1 (mass ratio) to prepare an inner - cycle odor - removing and denitrifying bacterial agent and an outer - cycle odor - removing and denitrifying bacterial agent respectively.

[0054] 2) Start - up and operation of the composite water purification process system

[0055] a) The place to be treated is an eel breeding pond. The water body in the breeding pond after 180 days of eel breeding is used as the water body of the in - situ odor - removing and denitrifying system (inner - cycle system) of the breeding pond; the water body after in - cycle treatment in the breeding pond flows out through the outlet of the breeding pond and enters the external tail - water treatment pond, serving as the external tail - water odor - removing and reuse denitrifying system (outer - cycle system).

[0056] Among them, the water quality indicators in the inner - cycle system are as follows: COD concentration 65.4 mg / L, nitrate concentration 12.4 mg / L, nitrite concentration 0.7 mg / L, ammonia - nitrogen concentration 1.4 mg / L, 2 - methylisoborneol concentration 300 ng / L.

[0057] b) Add an inner - cycle odor - removing and denitrifying bacterial agent to the in - situ odor - removing and denitrifying system (inner - cycle system) of the breeding pond, and the inoculation amount of the bacterial agent is 1.0 g / m 2 .

[0058] c) Install an intelligent feeding control system, temperature, dissolved oxygen and pH intelligent control systems in the in - situ odor - removing and denitrifying system (inner - cycle system) of the breeding pond, and control the dissolved oxygen not to be lower than 5 mg / L; the pH value is not lower than 6.5 and not higher than 8.5, ensuring that the inner - cycle system is within the suitable environment range for the growth of breeding organisms and the water purification of the bacterial agent (see Figure 2 ).

[0059] After the above in - situ treatment, the water quality of the breeding pond is detected: COD concentration 22 mg / L, nitrate concentration 8.8 mg / L, nitrite concentration 0.5 mg / L, ammonia - nitrogen concentration 1.0 mg / L, 2 - methylisoborneol concentration 200 ng / L.

[0060] d) The external tail - water odor - removing and denitrifying reuse system (outer - cycle system) is equipped with fillers (see Figure 2 ), and an outer - cycle odor - removing and denitrifying bacterial agent is inoculated on the fillers, and the inoculation amount of the bacterial agent is 0.1 g / m 2 . An electro - flocculation - microfiltration device is installed at the front end of the external tail - water odor - removing and denitrifying reuse system (outer - cycle system), and an ozone or ultraviolet disinfection system is installed at the end; at the same time, a dissolved oxygen and pH intelligent control system is installed. When the dissolved oxygen in the tail water is higher than 5 mg / L, aeration stops, and the pH value is not lower than 6.0 and not higher than 9.0. Ensure that the outer - cycle system is within the suitable environment range for the water purification of the bacterial agent.

[0061] After the external circulation treatment, the effluent COD concentration is 6.4 mg / L, nitrate concentration is 2.1 mg / L, nitrite concentration is 0.12 mg / L, ammonia nitrogen concentration is 0.13 mg / L, and 2-methylisoborneol concentration is 10 ng / L. The removal rates of the composite water purification process system reach COD≥90%, ammonia nitrogen≥90%, nitrite≥80%, nitrate≥80%, and 2-methylisoborneol≥96% respectively. The treated tail water is recycled back to the aquaculture pond for reuse.

[0062] e) The aquaculture tail water is in-situ treated by the in-situ odor removal and denitrification system (internal circulation system) of the aquaculture pond. After in-situ treatment, part of the tail water is diverted to the external tail water odor removal and denitrification recycling system (external circulation system) for further purification treatment, and finally flows back into the aquaculture pond again. Example 4

[0063] Application of the composite water purification process for odor removal and denitrification in shrimp aquaculture in the Yellow River Delta region:

[0064] 1) Preparation method of odor removal and denitrification bacterial agent

[0065] a) Strain propagation: Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria are respectively inoculated into the propagation medium with an inoculation amount of 10 wt%. Then, they are cultured at 20 °C for 72 hours. After the culture time ends, the bacteria are collected. The medium for strain propagation is, by mass percentage, glutamic acid (0.2%), glucose (0.2%), and sucrose (1%), and the balance is water.

[0066] b) Preparation of mixed bacterial powder: Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria obtained by propagation are respectively freeze-dried to obtain dry powders of each single strain.

[0067] Then, the dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of Enterococcus sp. YTLJ-N-SXH1 are assembled and mixed in a ratio of 2:1 to form an internal circulation type odor removal and denitrification mixed bacterial powder; the dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of nitrifying bacteria are assembled and mixed in a ratio of 3:1 to form an external circulation type odor removal and denitrification mixed bacterial powder.

[0068] c) Preparation of the auxiliary agent: Take the breeding feces and residual bait (obtained from the cultured prawns in this example), disinfect them with potassium bisulfate in a conventional manner, and then mix them with wheat bran, soybean meal, and sugarcane bagasse. The mass mixing ratio of feces and residual bait, wheat bran, soybean meal, and sugarcane bagasse is 1:1:1:1. After mixing, add the dried powder of Glutamicibacter sp. YTLJ-N-S7 after propagation, which is 0.4% of the mass of the mixture, and then add 0.1% of the mixture. After mixing evenly, control the water content of the reaction system to be 50%, and then carry out fermentation. After the fermentation is completed, collect the fermentation product, dry it, and add polyglutamic acid, which is 0.6% of the mass of the fermentation product, to prepare the auxiliary agent.

[0069] Among them, NH4NO3 and glutamic acid in the mixture are mixed at a mass ratio of 1:3;

[0070] d) Preparation of the bacterial agent: Mix the inner-circulation odor-removing and denitrifying mixed bacterial powder or the outer-circulation odor-removing and denitrifying mixed bacterial powder obtained in step b with the auxiliary agent obtained in step c at a mass ratio of 1:10 to prepare the inner-circulation odor-removing and denitrifying bacterial agent and the outer-circulation odor-removing and denitrifying bacterial agent respectively.

[0071] 2) Startup and operation of the composite water purification process system

[0072] a) The place to be treated is a prawn breeding pond in the Yellow River Delta region. The water body in the breeding pond is used as the water body of the in-situ odor-removing and denitrifying system (inner-circulation system) of the breeding pond; the water body after the inner-circulation treatment in the breeding pond flows out through the outlet of the breeding pond and enters the external tail water treatment pond, serving as the external tail water odor-removing and denitrifying reuse system (outer-circulation system).

[0073] Among them, the water quality indicators in the inner-circulation system are as follows: COD concentration 60mg / L, nitrate concentration 22mg / L, nitrite concentration 0.2mg / L, ammonia nitrogen concentration 1.5mg / L, 2-methylisoborneol concentration 122ng / L.

[0074] b) Add the inner-circulation odor-removing and denitrifying bacterial agent to the in-situ odor-removing and denitrifying system (inner-circulation system) of the breeding pond, and the bacterial inoculation amount is 3.0g / m 2 .

[0075] Install an intelligent feeding control system in the in-situ odor-removing and denitrifying system (inner-circulation system) of the breeding pond to accurately control the additional organic carbon source addition amount to be 5% of the feeding amount, stimulating the biological denitrification of the bacterial agent and the production of glutamic acid. Among them, the organic carbon source includes brown sugar, sugarcane bagasse, wheat bran, and rice bran; and install an intelligent control system for temperature, dissolved oxygen, and pH to control the dissolved oxygen in the system to be not less than 5mg / L; the pH value is not less than 6.5 and not higher than 8.5, ensuring that the inner-circulation system is within the suitable environment range for the growth of breeding organisms and the water purification of the bacterial agent (see Figure 2 ).

[0076] After the above in-situ treatment, the water quality of the aquaculture pond was detected. The concentrations of COD, nitrate, nitrite, and ammonia nitrogen were 30, 18, 0.1, and 0.88 mg / L respectively, and the concentration of 2-methylisoborneol was 50 ng / L.

[0077] d) The external tail water deodorization and denitrification reuse system (external circulation system) is equipped with packing (see Figure 2 ), and an external circulation type deodorization and denitrification bacterial agent is inoculated on the packing. The inoculation amount of the bacterial agent is 0.2 g / m 2 . An electrocoagulation-microfiltration device is installed at the front end of the external tail water deodorization and denitrification reuse system (external circulation system), and an ozone or ultraviolet disinfection system is installed at the end; at the same time, a dissolved oxygen and pH intelligent control system is installed. Aeration stops when the dissolved oxygen in the tail water is higher than 5 mg / L, and the pH value is not lower than 6.0 and not higher than 9.0. Ensure that the external circulation system is within the suitable environment range for the bacterial agent to purify water.

[0078] After external circulation treatment, the effluent COD concentration is 5.9 mg / L, nitrate concentration is 3.9 mg / L, nitrite concentration is 0.04 mg / L, ammonia nitrogen concentration is 0.12 mg / L, and 2-methylisoborneol concentration is 10.5 ng / L. The removal rates of each pollutant reach COD≥90%, ammonia nitrogen≥90%, nitrite≥80%, nitrate≥80%, and 2-methylisoborneol≥90%. The treated tail water is recycled back to the aquaculture pond for reuse.

[0079] e) The aquaculture tail water is subjected to in-situ treatment by the aquaculture pond in-situ deodorization and denitrification system (internal circulation system). After in-situ treatment, part of the tail water is diverted to the external tail water deodorization and denitrification reuse system (external circulation system) for further purification treatment, and finally flows back into the aquaculture pond again. Example 5

[0080] Deep treatment of deodorization and denitrification and recycling of aquaculture water during the aquaculture process of groupers in a coastal area:

[0081] 1) The preparation method of the deodorization and denitrification bacterial agent

[0082] a) Strain propagation: Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria were respectively inoculated into the propagation medium at an inoculation amount of 10 wt%, and cultured at 20 °C for 72 hours. After the culture time ended, the bacteria were collected. The medium for strain propagation is, by mass percentage, glutamic acid (0.2%), glucose (0.2%), and sucrose (1%), and the balance is water.

[0083] b) Preparation of mixed bacterial powder: The Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria obtained through propagation were freeze-dried respectively to obtain dry powder of each single strain.

[0084] The dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of Enterococcus sp. YTLJ-N-SXH1 were assembled and mixed at a ratio of 5:1 to prepare an in-loop odor-removing and denitrifying mixed bacterial powder; the dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of nitrifying bacteria were assembled and mixed at a ratio of 6:1 to prepare an out-loop odor-removing and denitrifying mixed bacterial powder.

[0085] c) Preparation of auxiliary agent: The aquaculture fecal residues and baits (obtained from culturing groupers in this example) were disinfected with potassium bisulfate in a conventional manner and then mixed with wheat bran, soybean meal, and bagasse. The mass mixing ratio of fecal residues and baits, wheat bran, soybean meal, and bagasse was 1:1:1:1. After mixing, 0.6% (by mass) of Glutamicibacter sp. YTLJ-N-S7 after propagation and 0.3% (by mass) of the mixture of NH4NO3 and glutamic acid were added. After mixing evenly, the water content of the reaction system was controlled to be 60%, and then fermentation was carried out. After the fermentation was completed, the fermentation product was collected, dried, and 0.8% of polyglutamic acid was added to prepare the auxiliary agent. Among them, NH4NO3 and glutamic acid in the mixture were mixed at a mass ratio of 1:2.

[0086] d) Preparation of bacterial agent: The in-loop odor-removing and denitrifying mixed bacterial powder or out-loop odor-removing and denitrifying mixed bacterial powder obtained in step b was mixed with the auxiliary agent obtained in step c at a ratio of 1:1 - 100 (by mass) respectively to prepare an in-loop odor-removing and denitrifying bacterial agent for aquaculture ponds and an out-loop odor-removing and denitrifying bacterial agent suitable for the external water treatment system of aquaculture ponds.

[0087] 2) Startup and operation of composite water purification process system

[0088] a) The place to be treated is a grouper aquaculture pond in a coastal area. The water body in this aquaculture pond serves as the water body of the in-situ odor-removing and denitrifying system (in-loop system) of the aquaculture pond; the water body after in-loop treatment in this aquaculture pond flows out through the outlet of the aquaculture pond and then enters the external tail water treatment pond, serving as the external tail water odor-removing and denitrifying reuse system (out-loop system).

[0089] Among them, the water quality indicators in the in-loop system are as follows: COD concentration 82 mg / L, nitrate concentration 17 mg / L, nitrite concentration 0.5 mg / L, ammonia nitrogen concentration 1.2 mg / L, geosmin concentration 137 ng / L.

[0090] b) Add an in - situ odor and nitrogen removal bacteria agent (internal circulation type) to the in - situ odor and nitrogen removal system of the aquaculture pond (internal circulation system). The inoculation amount of the bacteria agent is 5.0 g / m 2 .

[0091] c) Install an intelligent feeding control system in the in - situ odor and nitrogen removal system of the aquaculture pond (internal circulation system) to accurately control the additional organic carbon source addition amount to 10% of the feeding amount, stimulating the biological nitrogen removal of the bacteria agent and the production of glutamic acid. Among them, the organic carbon source includes sodium acetate, sodium butyrate, white sugar, and brown sugar; and install an intelligent control system for temperature, dissolved oxygen, and pH. Control the dissolved oxygen in the system to be not less than 5 mg / L; the pH value is not less than 6.5 and not higher than 8.5, ensuring that the internal circulation system is within the suitable environment range for the growth of aquaculture organisms and the water purification of the bacteria agent (see Figure 2 ).

[0092] After the above - mentioned in - situ treatment, the water quality of the aquaculture pond is detected. The concentrations of COD, nitrate, nitrite, and ammonia nitrogen are 35, 11, 0.1, and 0.6 mg / L respectively, and the concentration of geosmin in the tail water is 56 ng / L.

[0093] d) The external tail - water odor and nitrogen removal and reuse system (external circulation system) is equipped with fillers (see Figure 2 ), and an external - circulation type odor and nitrogen removal bacteria agent is inoculated on the fillers. The inoculation amount of the bacteria agent is 0.5 g / m 2 . An electro - flocculation - microfiltration device is installed at the front end of the external tail - water odor and nitrogen removal and reuse system (external circulation system), and an ozone or ultraviolet disinfection system is installed at the end; at the same time, an intelligent control system for dissolved oxygen and pH is installed. When the dissolved oxygen in the tail water is higher than 5 mg / L, aeration is stopped, and the pH value is not less than 6.0 and not higher than 9.0. Ensure that the external circulation system is within the suitable environment range for the water purification of the bacteria agent.

[0094] After the external - circulation treatment, the concentrations of COD, nitrate, nitrite, and ammonia nitrogen in the effluent are 8.0, 3.3, 0.1, and 0.1 mg / L respectively, and the concentration of geosmin is 35 ng / L. The removal rates of pollutants in the tail water reach COD≥90%, ammonia nitrogen≥90%, nitrite≥80%, nitrate≥80%, and geosmin≥70% respectively. The treated tail water is recycled back to the aquaculture pond for reuse.

[0095] e) The aquaculture tail water is subjected to in - situ treatment by the in - situ odor and nitrogen removal system of the aquaculture pond (internal circulation system). After the in - situ treatment, part of the tail water is diverted to the external tail - water odor and nitrogen removal and reuse system (external circulation system) for further purification treatment, and finally flows back into the aquaculture pond again. Example 6

[0096] Deep treatment and recycling of odor and nitrogen removal from aquaculture water during the industrialized farming of crucian carp:

[0097] 1) Preparation method of odor and nitrogen removal bacteria agent

[0098] a) Strain propagation: Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria were inoculated into the propagation medium at an inoculation amount of 10 wt%, and cultured at 20 °C for 72 hours. After the culture time ended, the bacteria were collected. The culture medium for strain propagation was, by mass percentage, glutamic acid (0.2%), glucose (0.2%), and sucrose (1%), with the balance being water.

[0099] b) Preparation of mixed bacterial powder: Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria obtained by propagation were freeze-dried respectively to obtain dry powders of each single strain.

[0100] The dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of Enterococcus sp. YTLJ-N-SXH1 were assembled and mixed in a ratio of 10:1 to prepare an internal circulation type odor-removing and denitrifying mixed bacterial powder; the dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of nitrifying bacteria were assembled and mixed in a ratio of 10:1 to prepare an external circulation type odor-removing and denitrifying mixed bacterial powder.

[0101] c) Preparation of auxiliary agent: The aquaculture fecal residues and baits (in this example, obtained from culturing crucian carp) were disinfected with potassium bisulfate in a conventional manner and then mixed with wheat bran, soybean meal, and bagasse. The mass mixing ratio of fecal residues and baits, wheat bran, soybean meal, and bagasse was 1:1:1:1. After mixing, 1.0% (by mass) of Glutamicibacter sp. YTLJ-N-S7 after propagation and 0.5% (by mass) of the mixture of NH4NO3 and glutamic acid were added, and after mixing evenly, the water content of the reaction system was controlled to be 80%, and then fermentation was carried out. After the fermentation ended, the fermentation product was collected, dried, and 1.0% of polyglutamic acid was added to prepare the auxiliary agent. Among them, NH4NO3 and glutamic acid in the mixture were mixed in a mass ratio of 1:5.

[0102] d) Preparation of bacterial agent: The internal circulation type odor-removing and denitrifying mixed bacterial powder or the external circulation type odor-removing and denitrifying mixed bacterial powder obtained in step b was mixed with the auxiliary agent obtained in step c at a mass ratio of 1:100 respectively to prepare an internal circulation type odor-removing and denitrifying bacterial agent for aquaculture ponds and an external circulation type odor-removing and denitrifying bacterial agent suitable for the external water treatment system of aquaculture ponds.

[0103] 2) Start-up and operation of the composite water purification process system

[0104] a) The place to be treated is a factory-scale culture pond for crucian carp. The water body in the culture pond serves as the water body of the in-situ odor and nitrogen removal system (internal circulation system) of the culture pond. The water body after internal circulation treatment in the culture pond flows out through the water outlet of the culture pond and enters the external tail water treatment pond, serving as the external tail water odor and nitrogen removal and reuse system (external circulation system).

[0105] Among them, the water quality indicators in the internal circulation system are as follows: COD concentration 73 mg / L, nitrate concentration 20 mg / L, nitrite concentration 0.4 mg / L, ammonia nitrogen concentration 1.4 mg / L, geosmin concentration 165 ng / L.

[0106] b) An internal circulation type odor and nitrogen removal bacterial agent is added to the in-situ odor and nitrogen removal system (internal circulation system) of the culture pond. The inoculation amount of the bacteria is 10.0 g / m 2 .

[0107] c) An intelligent feeding control system is installed in the in-situ odor and nitrogen removal system (internal circulation system) of the culture pond to accurately control the additional organic carbon source addition amount to 1% of the feeding amount, stimulating the biological denitrification of the bacterial agent and the production of glutamic acid. Among them, the organic carbon source includes sodium acetate, sodium propionate, sodium butyrate, white sugar, and brown sugar; and an intelligent control system for temperature, dissolved oxygen, and pH is installed, controlling the dissolved oxygen in the system to be not less than 5 mg / L; the pH value is not less than 6.5 and not higher than 8.5, ensuring that the internal circulation system is within the suitable environment range for the growth of cultured organisms and the water purification of the bacterial agent (see Figure 2 ).

[0108] After the above in-situ treatment, the water quality of the culture pond is detected. The COD concentration is 40 mg / L, the nitrate concentration is 8.4 mg / L, the nitrite concentration is 0.4 mg / L, the ammonia nitrogen concentration is 0.7 mg / L, and the geosmin concentration is 85 ng / L.

[0109] d) The external tail water odor and nitrogen removal and reuse system (external circulation system) is equipped with packing (see Figure 2 ), and an external circulation type odor and nitrogen removal bacterial agent is inoculated on the packing. The inoculation amount of the bacterial agent is 1.0 g / m 2 . An electrocoagulation-microfiltration device is installed at the front end of the external tail water odor and nitrogen removal and reuse system (external circulation system), and an ozone or ultraviolet disinfection system is installed at the end; at the same time, an intelligent control system for dissolved oxygen and pH is installed. Aeration stops when the dissolved oxygen in the tail water is higher than 5 mg / L, and the pH value is not less than 6.0 and not higher than 9.0. Ensure that the external circulation system is within the suitable environment range for the water purification of the bacterial agent.

[0110] After external circulation treatment, the effluent has a COD concentration of 8.0 mg / L, a nitrate concentration of 2.7 mg / L, a nitrite concentration of 0.09 mg / L, an ammonia nitrogen concentration of 0.08 mg / L, and a geosmin concentration of 15 ng / L. The pollutant removal rates of the composite system reach COD ≥ 90%, ammonia nitrogen ≥ 90%, nitrite ≥ 80%, nitrate ≥ 80%, and geosmin ≥ 90%. The treated tail water is refluxed to the aquaculture pond for recycling.

[0111] e) The aquaculture tail water is in-situ treated by the in-situ odor removal and denitrification system (internal circulation system) of the aquaculture pond. After in-situ treatment, part of the tail water is diverted to the external tail water odor removal, denitrification and reuse system (external circulation system) for further purification treatment, and finally flows back into the aquaculture pond again.

Claims

1. A deodorizing and denitrifying bacterium, characterized in that: The odor-removing and denitrifying bacterium is Glutamicibacter sp. YTLJ-N-S7, which was deposited at the Guangdong Microbial Culture Collection Center on May 26, 2021, with the deposit number GDMCC No: 61694, the taxonomic name Glutamicibacter sp., and the deposit address in Guangzhou, China.

2. Use of the odor-removing and denitrifying bacteria according to claim 1, characterized in that: The application of Glutamicibacter sp. YTLJ-N-S7 in purifying water, removing odor, and denitrifying.

3. A water purification, odor removal, and denitrification bacterial agent, characterized in that: The bacterial agent contains Glutamicibacter sp. YTLJ-N-S7 described in claim 1.

4. The water purification, odor removal, and denitrification bactericide according to claim 3, characterized in that: The bacterial agent is Glutamicibacter sp. YTLJ-N-S7; or the bacterial agent is a mixture of Glutamicibacter sp. YTLJ-N-S7 and Enterococcus sp. YTLJ-N-SXH1; or the bacterial agent is a mixture of Glutamicibacter sp. YTLJ-N-S7 and nitrifying bacteria; or the bacterial agent is a mixture of Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria; Enterococcus sp. YTLJ-N-SXH1 was deposited at the Guangdong Microbial Culture Collection Center on November 26, 2021, with the deposit number GDMCC No: 62080, the taxonomic name Enterococcus sp., and the deposit address in Guangzhou, China.

5. The water purification, odor removal, and denitrification bactericide according to claim 4, characterized in that: Glutamicibacter sp. YTLJ-N-S7, Enterococcus sp. YTLJ-N-SXH1, and nitrifying bacteria are respectively propagated and dried to obtain dry powders of each strain, and then the dry powder of Glutamicibacter sp. YTLJ-N-S7 after propagation and the dry powder of Enterococcus sp. YTLJ-N-SXH1 are mixed according to a mass ratio of 1-10:1 to obtain powder A; The dry powder of Glutamicibacter sp. YTLJ-N-S7 and the dry powder of nitrifying bacteria are mixed according to a mass ratio of 1-10:1 to obtain powder B; Each of the above-mentioned bacterial powders is mixed with an adjuvant in a mass ratio of 1:1 to 100 to obtain each bacterial agent, and the total effective viable count of each bacterial agent is ≥ 1.0×10 9 CFU / mL; Or, the mixtures obtained by mixing each powder with an auxiliary agent are mixed again to obtain the bacterial agent.

6. The water purification, odor removal and denitrification bactericide according to claim 5, characterized in that: The auxiliary agent is prepared by mixing the disinfected aquaculture feces and bait residues with wheat bran, soybean meal, and bagasse according to a mass mixing ratio of 1:1:1:1; after mixing, 0.1%-1.0% of the dry powder of Glutamicibacter sp. YTLJ-N-S7 after propagation is added, and then 0.05%-0.5% of mixture A is added. After mixing evenly, the water content of the reaction system is controlled to be 40%-80%, and then fermentation is carried out. The fermented product is collected and mixed with 0.5-1.0% of polyglutamic acid based on the mass of the fermented product to obtain the auxiliary agent; where mixture A is a mixture of NH4NO3 and glutamic acid according to a mass ratio of 1:1-5.

7. Use of the microbial agent according to any one of claims 3-6, characterized in that: Application of the microbial agent in water purification, odor removal and denitrification.

8. The application according to claim 7, wherein: Application of the microbial agent in comprehensively and intelligently treating the water bodies inside and outside the aquaculture pond, removing odor and denitrifying.

9. The application according to claim 7, wherein: The comprehensive and intelligent treatment of the water bodies inside and outside the aquaculture pond means that the microbial agent obtained by mixing the bacterial powder A with the auxiliary agent is used to treat the in-situ internal circulating water of the aquaculture pond; the microbial agent obtained by mixing the bacterial powder B with the auxiliary agent is used to treat the external circulating tail water connected to the aquaculture pond.

10. The application according to claim 9, wherein: The inoculation amount of the bacterial agent in the treatment, odor removal, and denitrification of the in-situ recirculating water in the aquaculture pond is 1.0 - 10.0 g / m 2 ; the inoculation amount of the bacterial agent in the treatment, odor removal, and denitrification of the externally connected external circulating tail water of the aquaculture pond is 0.1 - 1.0 g / m 2 .

Images