Biological treatment method for high-salt organic wastewater

Abstract

The invention discloses a high-salinity organic wastewater biological treatment method which is characterized by comprising the following steps: step 1, screening halophilic bacteria: directly screening the required halophilic bacteria through soil of saline-alkali soil, and then carrying out secondary screening on flora mixed culture obtained by primary screening; the method has the beneficial effects that halophilic bacteria ZC2403-SYL, ZC2404-SYT and halotolerant bacteria ZC2402-MT which can still degrade pollutants are screened out in a high-salt environment by utilizing a microbial method, organic matters including triethylamine, n-butylamine and formamide can be degraded in the high-salt environment, the degradation rate can reach 90% or above within 72 hours, and the method is simple and convenient to operate and has a wide application prospect. A high-efficiency salt-tolerant biological treatment system and a high-efficiency bacterium, namely a halophilic bacterium system, are constructed aiming at high-salt and refractory organic pollutants, the three strains obtained by screening are mixed and cultured to quickly form a high-salt organic wastewater high-efficiency degradation bacterium agent ZC-SY, and the high-salt organic wastewater high-efficiency degradation bacterium agent ZC-SY is put into actual high-salt organic wastewater to be used, so that stable operation can be achieved. The problem of treating the organic high-salinity wastewater in practice can be effectively solved, and the water treatment cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of high-salt wastewater treatment, and in particular to a biological treatment method for high-salt organic wastewater. Background Art

[0002] High-salt wastewater refers to wastewater with a salt content of at least 1%. In addition to a large amount of inorganic salts, this type of wastewater also contains organic matter and a total dissolved solids (TDS) with a mass fraction of ≥3.5%. It is one of the most difficult wastewaters to treat.

[0003] The source of organic high-salt wastewater is mainly from production wastewater in the petrochemical, food fermentation, pharmaceutical and other industries. These wastewaters need to be added with a large amount of salt substances, such as sodium chloride, sodium sulfate, calcium chloride, etc., during the production process to remove oil, impurities, and adjust pH value.

[0004] There are many methods for treating organic high-salt wastewater, such as incineration, electrolysis, membrane separation, ion exchange, etc. However, incineration will produce secondary pollutants such as nitrogen oxides and dioxins; electrolysis has high operating costs; in membrane separation, as the feed concentrates, the salt concentration becomes higher and higher, the membrane will have defects, and suspended matter in the wastewater will easily clog the membrane; and ion exchange is mostly used for pretreatment of biological methods to remove metal ions that inhibit microorganisms in wastewater, but the removal effect of organic matter is poor.

[0005] In the existing technology, the biofilm method produces less sludge, is easy to separate solid and liquid, and has a stable denitrification effect, and is often used to treat high-nitrogen wastewater. However, high sulfate stress in the wastewater causes an osmotic pressure imbalance in the microbial cells, which greatly reduces the denitrification effect.

[0006] In view of the above technical problems, for example, the announcement number CN117185502A discloses a biological denitrification method for high-salt and high-nitrogen wastewater, which quickly prepares a denitrifying composite bacterial agent to avoid the cumbersome process of multiple streaking separations of a single bacterial species and re-compounding, and optimizes the biofilm startup conditions suitable for the immobilization of high-salt wastewater bacterial agents, shortening the startup cycle of the high-salt wastewater biofilm method, and at the same time using denitrifying bacteria to inhibit sulfate reduction and avoid the problem of secondary sulfide pollution;

[0007] The above patents also have the following deficiencies: they are unable to degrade pollutants in a high-salt environment, and the efficiency of sewage treatment is low. The traditional high-salt organic wastewater treatment process is complex and costly, and it is difficult to degrade organic pollutants in a high-salt environment. Summary of the invention

[0008] The purpose of the present invention is to provide a biological treatment method for high-salt organic wastewater, which uses microbial methods to screen out halophilic bacteria and salt-tolerant bacteria that can degrade pollutants in a high-salt environment. It can effectively solve the problem of treating organic high-salt wastewater in practice, reduce water treatment costs, and solve the problems raised in the above background technology.

[0009] To achieve the above object, the present invention provides the following technical solution: a biological treatment method for high-salt organic wastewater, comprising the following steps:

[0010] Step 1: Screening of halophilic bacteria: directly screen the desired halophilic bacteria from saline-alkali soil, and then rescreen the bacterial mixed culture obtained from the initial screening;

[0011] Step 2, screening of salt-tolerant bacteria, where salt-tolerant bacteria are directly screened from pre-selected activated sludge, and then the mixed culture of bacteria obtained from the initial screening is rescreened;

[0012] Step 3, separation and purification of strains, the mixed culture of the above-obtained bacterial flora is transferred to a high-salt organic medium at an inoculation rate of 2%, and the halophilic bacteria and the halotolerant bacteria are further streaked and purified by the plate streak method until a single colony grows;

[0013] Step 4, identification of strains, sending the purified 2 halophilic bacteria and 1 halotolerant bacteria to the assay site for 16SrRNA gene sequencing, and comparing the sequencing results with the nucleic acid sequences in the GenBank database.

[0014] Exemplarily, the screening method in the screening of halophilic bacteria is as follows:

[0015] The collected soil samples were made into a solution with PBS buffer solution, and the solution was shaken on a shaker for 30 minutes to prepare a soil suspension. 100 mL of the mixed soil suspension was taken and added to 1 L of primary screening culture medium, followed by rescreening, and the addition amount was 1-3%.

[0016] Exemplarily, the primary screening culture medium is 30-60 g / L sodium chloride, 1 g / L glucose, 0.05 g / L nitrogen source, 0.001 g / L phosphorus source, and pH is between 7.2-7.8;

[0017] Culture temperature: 33-37℃, aerobic culture;

[0018] During the screening process, the COD concentration is monitored regularly. After 3-5 rounds of degradation, the inorganic salt concentration is gradually increased to 60-90 g / L. After another 3-5 rounds of degradation, a mixed culture of bacteria that can tolerate high-salt wastewater not exceeding 90 g / L is obtained.

[0019] Exemplarily, the screening method in the screening of salt-tolerant bacteria is as follows:

[0020] The dosage of activated sludge during screening is 5g / L;

[0021] The primary screening culture medium is 30-60g / L sodium chloride, 1g / L glucose, 0.05g / L nitrogen source, 0.001g / L phosphorus source, pH 7.2-7.8. Culture temperature: 33-37℃, aerobic culture. In addition, during the screening process, the COD concentration is regularly monitored. After 3-5 rounds of degradation, the inorganic salt concentration is gradually increased to 60-90g / L. After another 3-5 rounds of degradation, a mixed culture of bacteria that can tolerate high-salt wastewater not exceeding 90g / L is obtained.

[0022] Exemplarily, the dosage during the rescreening process is 1-3%;

[0023] The secondary screening culture medium is: 60-90g / L sodium chloride, 1g / L organic nitrogen, 0.02g / L phosphorus source, pH between 7.2-7.8. Culture temperature: 33-37℃, aerobic culture.

[0024] Exemplarily, during the screening process, the concentration of total nitrogen, ammonia nitrogen, and ammonia nitrogen release need to be monitored regularly. After 3-5 rounds of degradation, a mixed culture of bacteria that can tolerate no more than 90 g / L of high-salt organic wastewater must be obtained;

[0025] Among them, the organic nitrogen in the re-screened culture medium are n-butylamine, formamide and triethylamine, all of which can be degraded.

[0026] Exemplarily, the formula of the high-salt organic culture medium is 30-60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter, n-butylamine: formamide: triethylamine = 1:1:1, 0.001 g / L phosphorus source, pH between 7.2-7.8;

[0027] The culture was cultured at 33°C in a shaking incubator until the logarithmic phase, and the culture solution was diluted and spread on a high-salt organic solid culture medium using the dilution spread plate method.

[0028] Exemplarily, in the high-salt organic solid culture medium, the culture medium components are 30-60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter, n-butylamine: formamide: triethylamine = 1:1:1, 0.001 g / L phosphorus source, 2% agar, pH between 7.2-7.8;

[0029] Place in a 33°C constant temperature incubator and culture for 2-3 days.

[0030] Exemplarily, during the purification, a single bacterial colony grown in a solid culture medium is isolated using an inoculation needle in an ultra-clean bench.

[0031] Illustratively, during the purification process, the operation is repeated three or more times until the colonies grown on the plate have a single morphology, thereby obtaining two purified halophilic bacteria and one halotolerant bacteria.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] Using microbial methods, halophilic bacteria ZC2403-SYL, ZC2404-SYT and halotolerant bacteria ZC2402-MT that can still degrade pollutants in a high-salt environment were screened out. They can degrade organic triethylamine, n-butylamine and formamide in a high-salt environment, and the degradation rate can reach more than 90% within 72 hours. An efficient salt-tolerant biological treatment system and a high-efficiency bacteria, namely, halophilic bacteria system, were constructed for high-salt and difficult-to-degrade organic pollutants. The three strains screened were mixed and cultured to quickly form an efficient degradation bacterial agent ZC-SY for high-salt organic wastewater. When put into actual high-salt organic wastewater, it can achieve stable operation, which can effectively solve the problem of treating organic high-salt wastewater in practice and reduce the cost of water treatment.

[0034] Other features and advantages of the present invention will be described in the following description, and partly become obvious from the description, or be understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of the method of the present invention;

[0036] Figure 2 It is a curve diagram of organic nitrogen concentration variation in the degradation experiment of triethylamine wastewater of the present invention;

[0037] Figure 3 It is a curve diagram of organic nitrogen concentration change in the degradation experiment of n-butylamine wastewater of the present invention;

[0038] Figure 4 It is a curve diagram of organic nitrogen concentration change in the degradation experiment of formamide wastewater of the present invention;

[0039] Figure 5 It is a curve diagram of organic nitrogen degradation rate change of the present invention. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] The deposit information of the alkaliphilic halomonas involved in the following examples is as follows: depository name: General Microbiological Center of China Microbiological Culture Collection Administration; depository address: No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing; deposit date: August 22, 2024; deposit number: CGMCC No.31700;

[0042] The deposit information of the marine Moraxella rosellii involved in the following examples is as follows: depository name: General Microbiology Center of China Microbiological Culture Collection Administration; depository address: No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing; deposit date: May 10, 2024; deposit number: CGMCC No. 31700;

[0043] The present invention provides a method for biological treatment of high-salt organic wastewater, comprising the following steps:

[0044] Step 1: Screening of halophilic bacteria: directly screen the desired halophilic bacteria from saline-alkali soil, and then rescreen the bacterial mixed culture obtained from the initial screening;

[0045] Halophilic bacteria are directly screened from saline-alkali soil. The screening method is as follows:

[0046] The collected soil samples were made into a solution with PBS buffer solution, and the solution was shaken on a shaker for 30 min to make a soil suspension. 100 mL of the mixed soil suspension was taken and added to 1 L of primary screening culture medium;

[0047] The primary screening culture medium is: 30-60g / L sodium chloride, 1g / L glucose, 0.05g / L nitrogen source, 0.001g / L phosphorus source, pH between 7.2-7.8;

[0048] Culture temperature: 33-37℃, aerobic culture;

[0049] In addition, during the screening process, the COD concentration was monitored regularly, and after 3-5 rounds of degradation, the inorganic salt concentration was gradually increased to 60-90 g / L. After another 3-5 rounds of degradation, a mixed culture of bacteria that could tolerate high-salt wastewater not exceeding 90 g / L was obtained.

[0050] The mixed culture of the bacterial flora obtained by the initial screening is rescreened, and the dosage is 1-3%. The rescreening medium is: 60-90g / L sodium chloride, 1g / L organic nitrogen, 0.002g / L phosphorus source, and the pH is between 7.2-7.8;

[0051] Culture temperature: 33-37℃, aerobic culture;

[0052] In addition, during the screening process, COD concentration and ammonia nitrogen release were regularly monitored, and after 3-5 rounds of degradation, a mixed culture of bacteria that could tolerate high-salinity organic wastewater not exceeding 90g / L was obtained;

[0053] Among them, the organic matter in the re-screened culture medium was n-butylamine, formamide and triethylamine, all of which could be completely degraded.

[0054] Step 2, screening of salt-tolerant bacteria, where salt-tolerant bacteria are directly screened from pre-selected activated sludge, and then the mixed culture of bacteria obtained from the initial screening is rescreened;

[0055] The salt-tolerant bacteria were directly screened from activated sludge. The dosage of activated sludge was 5g / L. The screening method was as follows:

[0056] The primary screening culture medium is: 30-60g / L sodium chloride, 1g / L glucose, 0.05g / L nitrogen source, 0.001g / L phosphorus source, pH between 7.2-7.8;

[0057] Culture temperature: 33-37℃, aerobic culture;

[0058] In addition, during the screening process, the COD concentration was monitored regularly, and after 3-5 rounds of degradation, the inorganic salt concentration was gradually increased to 60-90 g / L. After another 3-5 rounds of degradation, a mixed culture of bacteria that could tolerate high-salt wastewater not exceeding 90 g / L was obtained.

[0059] The mixed culture of the bacterial flora obtained by the initial screening is rescreened, and the dosage is 1-3%. The rescreening medium is: 60-90g / L sodium chloride, 1g / L organic nitrogen, 0.02g / L phosphorus source, and the pH is between 7.2-7.8;

[0060] Culture temperature: 33-37℃, aerobic culture;

[0061] In addition, during the screening process, the concentrations of total nitrogen and ammonia nitrogen, as well as the amount of ammonia nitrogen released, were regularly monitored. After 3-5 rounds of degradation, a mixed culture of bacteria that could tolerate high-salinity organic wastewater not exceeding 90 g / L was obtained;

[0062] Among them, the organic nitrogen in the re-screened culture medium were n-butylamine, formamide and triethylamine, all of which could be degraded.

[0063] Step 3, separation and purification of strains, the mixed culture of the above-obtained bacterial flora is transferred to a high-salt organic medium at an inoculation rate of 2%, and the halophilic bacteria and the halotolerant bacteria are further streaked and purified by the plate streak method until a single colony grows;

[0064] Separation: Under sterile conditions, the obtained mixed culture of the above-mentioned flora was transferred to a high-salt organic medium at an inoculum volume of 2%. The formula of the high-salt organic medium is: 30-60g / L sodium chloride, 0.5g / L peptone, 0.25g / L yeast powder, 1g / L organic matter, n-butylamine: formamide: triethylamine = 1:1:1, 0.001g / L phosphorus source, pH between 7.2-7.8;

[0065] Cultivate at 33°C in a shaking incubator until the logarithmic phase, and dilute and spread the culture solution on a high-salt organic solid medium using a dilution spreading plate method. The high-salt organic solid medium comprises 30-60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter n-butylamine: formamide: triethylamine = 1:1:1, 0.001 g / L phosphorus source, 2% agar, and a pH between 7.2 and 7.8;

[0066] Place in a 33°C constant temperature incubator and culture for 2-3 days.

[0067] Purification: In the clean bench, use an inoculation needle to separate the single colonies grown in the solid culture medium, and use the plate streak method to further streak and purify the halophilic bacteria and halotolerant bacteria until a single colony grows. Repeat the operation more than 3 times until the colonies grown on the plate have a single morphology, and then 2 purified halophilic bacteria and 1 halotolerant bacteria are obtained.

[0068] Step 4, identification of strains, sending the purified 2 halophilic bacteria and 1 halotolerant bacteria to the assay site for 16SrRNA gene sequencing, and comparing the sequencing results with the nucleic acid sequences in the GenBank database.

[0069] At the same time, MEGA 5.0 software method was used to construct a reasonable phylogenetic tree;

[0070] The taxonomic status of the strain was finally identified;

[0071] The identification results and physiological characteristics of the strains are shown in the following chart:

[0072]

[0073] According to the above, for organic wastewater with a total salt content of 3-8%, halophilic bacteria and salt-tolerant bacteria are domesticated in advance and put into the biochemical pool for biochemical treatment;

[0074] Among them: high-salt organic wastewater with poor biodegradability can be pretreated by advanced oxidation, adsorption and other physical and chemical methods, and then degraded by domesticated halophilic and salt-tolerant bacteria after improving biodegradability;

[0075] When the effluent salinity is limited, deep treatment such as desalination can be used to make the effluent salinity meet the standard;

[0076] The main technical point of the present invention is that the halophilic bacteria and halotolerant bacteria capable of degrading pollutants are screened out in a high-salt environment by a microbial method, which can effectively solve the problem of treating organic high-salt wastewater in practice, reduce water treatment costs, and improve water treatment efficiency.

[0077] The present invention also includes the following embodiments:

[0078] The following examples are applicable to the present invention, but are not intended to limit the scope of the present invention;

[0079] Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art.

[0080] The determination method of ammonia nitrogen in the following examples is: Nessler's reagent photometry; the determination method of total nitrogen is: ultraviolet spectrophotometry.

[0081] Example 1 Isolation and purification of bacterial strains

[0082] Acclimation Enrichment:

[0083] 1. Halophilic bacteria: a mixed culture of bacteria that can tolerate high-salt wastewater not exceeding 90 g / L was directly screened from a saline-alkali soil, with an addition rate of 1%. The culture medium formula is: 60 g / L sodium chloride, 1 g / L organic nitrogen, 0.2 g / L phosphorus source, and pH between 7.2-7.8;

[0084] Among them, the organic nitrogen in the culture medium can be degraded by using n-butylamine, formamide and triethylamine in turn;

[0085] Culture temperature: 33°C, aerobic culture. In addition, during the screening process, the total nitrogen, ammonia nitrogen concentration, and ammonia nitrogen release are regularly monitored. After 3-5 rounds of degradation, a mixed culture of bacteria that can tolerate high-salt organic wastewater not exceeding 90g / L is obtained, and the halophilic bacteria that can degrade organic matter can be separated and purified.

[0086] 2. Salt-tolerant bacteria: Add activated sludge to screen for bacteria that can tolerate high-salt wastewater not exceeding 90g / L. The dosage is 1%. The culture medium is: 60g / L sodium chloride, 1g / L organic nitrogen, 0.2g / L phosphorus source, and the pH is between 7.2-7.8.

[0087] Culture temperature: 33°C, aerobic culture;

[0088] The organic nitrogen in the culture medium was degraded by n-butylamine, formamide, and triethylamine in turn. Culture temperature: 33°C, aerobic culture;

[0089] In addition, during the screening process, the total nitrogen, ammonia nitrogen concentration, and ammonia nitrogen release are monitored regularly. After 3-5 rounds of degradation, a mixed culture of bacteria that can tolerate high-salt organic wastewater not exceeding 90g / L is obtained, and the salt-tolerant bacteria that can degrade organic matter can be isolated and purified.

[0090] Separation:

[0091] 1. Halophilic bacteria: Under sterile conditions, the mixed culture of halophilic bacteria obtained by domestication and enrichment is transferred to a high-salt organic medium at an inoculum rate of 2%. The formula of the high-salt organic medium is: 30-60g / L sodium chloride, 0.5g / L peptone, 0.25g / L yeast powder, 1g / L organic matter (n-butylamine: formamide: triethylamine = 1:1:1), 0.01g / L phosphorus source, pH between 7.2-7.8;

[0092] Cultivate at 33°C in a shaking incubator until the logarithmic phase, and dilute and spread the culture solution on a high-salt organic solid medium using a dilution spread plate method. The high-salt organic solid medium contains 30-60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter (n-butylamine: formamide: triethylamine = 1:1:1), 0.001 g / L phosphorus source, 2% agar, and a pH between 7.2 and 7.8;

[0093] Place in a 33°C constant temperature incubator and culture for 2-3 days.

[0094] 2. Salt-tolerant bacteria: Under sterile conditions, the salt-tolerant bacteria mixed culture obtained by domestication and enrichment is transferred to a high-salt organic medium at an inoculum rate of 2%. The formula of the high-salt organic medium is: 30-60g / L sodium chloride, 0.5g / L peptone, 0.25g / L yeast powder, 1g / L organic matter (n-butylamine: formamide: triethylamine = 1:1:1), 0.01g / L phosphorus source, pH between 7.2-7.8;

[0095] Cultivate at 33°C in a shaking incubator until the logarithmic phase, and dilute and spread the culture solution on a high-salt organic solid medium using a dilution spread plate method. The high-salt organic solid medium contains 30-60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter (n-butylamine: formamide: triethylamine = 1:1:1), 0.01 g / L phosphorus source, 2% agar, and a pH between 7.2 and 7.8;

[0096] Place in a 33°C constant temperature incubator and culture for 2-3 days.

[0097] 3. Purification

[0098] In the clean bench, single colonies grown in the solid culture medium were isolated with an inoculation needle, and the halophilic and halophilic bacteria were further streaked and purified using the plate streak method until single colonies were grown;

[0099] The operation was repeated three times or more until the colonies grown on the plate had a single morphology, thereby obtaining two purified halophilic bacteria and one halotolerant bacteria.

[0100] Example 2, identification of strains

[0101] The purified 2 halophilic bacteria and 1 halophilic bacteria were sent to the sequencing center for 16S rRNA gene sequencing. The sequencing results were compared with the nucleic acid sequences in the GenBank database, and a reasonable phylogenetic tree was constructed using the MEGA 5.0 software method.

[0102] The taxonomic status of the strain was finally identified;

[0103] The identification results and physiological characteristics of the strains are shown in the following table:

[0104]

[0105] The registration number of the collection of alkaliphilic halomonas is CGMCC No.31700;

[0106] The deposit is requested and the following biological material (strain) for identification is indicated: ZC2403-SYL.

[0107] The registration number of the marine Moraxella Roselloniae collection center is CGMCC No.30575;

[0108] The deposit is requested and the following biological material (strain) for identification is indicated: ZC2402-MT.

[0109] Example 3, mixed culture method of strains:

[0110] The mixed culture method of strains ZC2403-SYL, ZC2404-SYT and ZC2402-MT comprises the following steps:

[0111] 1. Activation: Single colonies of strains ZC2403-SYL, ZC2404-SYT and ZC2402-MT from solid plates were transferred to high-salt organic culture medium (system 20 mL), the culture medium components were 60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter, n-butylamine: formamide: triethylamine = 1:1:1, 0.1 g / L phosphorus source, the shaking speed was 100 rpm, and the shaking was cultured at 33°C for 24-48 hours until the logarithmic phase; the single carbon source culture medium components were: 0.5 g / L dimethyl phosphite, 5 g / L nitrogen source, 2-10 g / L inorganic salt, pH between 7.2-7.8.

[0112] 2. Transfer: The mixed bacterial solution activated in the logarithmic phase in process 1 was transferred to a 1L seed tank at a 5% access volume for cultivation. The temperature of the seed tank was controlled to be maintained at 33°C, the rotation speed was maintained at 100rpm, the dissolved oxygen DO was controlled at 5mg / L, and the culture was carried out for 48h. Organic matter was added in time, and the concentration of organic matter was gradually increased to 2g / L. The organic matter composition was n-butylamine: formamide: triethylamine = 1:1:1, so that the bacteria could tolerate higher high-salt organic wastewater and significantly increase the degradation rate of organic matter.

[0113] The composition of the culture medium of the seed tank is as follows: organic matter, n-butylamine: formamide: triethylamine = 1:1:1, 2 g / L, glucose 0.2 g / L, sodium dihydrogen phosphate 0.2 g / L, MgCl2 0.02 g / L, CaCl2 0.03 g / L, NaHCO3 0.5 g / L, pH 7.2.

[0114] 3. Expansion culture: The high-salt organic nitrogen-degrading bacterial solution cultured in the seed tank of process 2 was transferred to a 10L fermentation tank at a 5% inoculation rate for expansion culture. The composition of the fermentation tank culture medium was the same as that of the seed tank. The physical and chemical parameter indicators were: temperature 33°C, rotation speed 100rpm, dissolved oxygen 8mg / L, and fermentation time 72h;

[0115] After the fermentation is completed, the effective live bacteria count in the tank culture liquid can reach more than 109 / ml. After the fermentation culture liquid is taken out of the tank and packaged in a plastic barrel, a mixed culture liquid of high-salt organic efficient degradation strains ZC2403-SYL, ZC2404-SYT and ZC2402-MT can be obtained.

[0116] Example 4, degradation experiment of triethylamine wastewater by mixed bacterial liquid of ZC2403-SYL, ZC2404-SYT and ZC2402-MT:

[0117] 1% of the mixed bacterial solution of ZC2403-SYL, ZC2404-SYT and ZC2402-MT cultured in the present invention was added to a single carbon source medium shake flask containing 0.5 g / L triethylamine, with a total nitrogen concentration of 95 mg / L. The medium formula contained: 0.5 g / L triethylamine, 0.01 g / L phosphorus source, 60 g / L NaCl, 0.03 g / L CaCl2 and 0.5 g / L NaHCO3.

[0118] The shaking speed was 100 rpm and the temperature was 33°C. The culture was carried out in a shaking incubator. Samples were taken at 0h, 12h, 24h, 36h, 48h, 60h and 72h to measure the concentrations of ammonia nitrogen and total nitrogen. At 72h of culture, the organic nitrogen was reduced to 5mg / L to achieve the effect of complete release. Figure 2 shown.

[0119] Example 5, degradation experiment of n-butylamine wastewater by mixed bacterial liquid of ZC2403-SYL, ZC2404-SYT and ZC2402-MT:

[0120] 1% of the mixed strains of ZC2403-SYL, ZC2404-SYT and ZC2402-MT cultured in the present invention was added to a single carbon source medium shake flask containing 0.5 g / L n-butylamine, the system was 100 mL, the total nitrogen concentration was 96 mg / L, and the medium formula contained: 0.5 g / L n-butylamine, 0.01 g / L phosphorus source, 60 g / L NaCl, 0.03 g / L CaCl2 and 0.5 g / L NaHCO3;

[0121] The shaking speed was 100 rpm and the temperature was 33°C. Samples were taken at 0 h, 12 h, 24 h, 36 h, and 48 h to determine the concentrations of ammonia nitrogen and total nitrogen;

[0122] After 48 hours of cultivation, the organic nitrogen dropped to 2 mg / L and the effect of complete release was achieved. Figure 3 shown.

[0123] Example 6, Degradation test of formamide wastewater by mixed bacterial liquid of ZC2403-SYL, ZC2404-SYT and ZC2402-MT:

[0124] 1% of the mixed strains of ZC2403-SYL, ZC2404-SYT and ZC2402-MT cultured in the present invention was added to a single carbon source medium shake flask containing 0.5 g / L formamide, with a total nitrogen concentration of 156 mg / L. The medium formula included: 0.5 g / L formamide, 0.01 g / L phosphorus source, 60 g / L NaCl, 0.03 g / L CaCl2 and 0.5 g / L NaHCO3. The shaker speed was 100 rpm, the temperature was 33°C, and the culture was carried out in a shaker;

[0125] Samples were taken at 0h, 12h, 24h, 36h, 48h, and 60h to determine the concentrations of ammonia nitrogen and total nitrogen;

[0126] After 48 hours of cultivation, the organic nitrogen dropped to 4 mg / L and the effect of complete release was achieved. Figure 4 shown.

[0127] Example 7, a method for quickly forming a bacterial agent from a mixed bacterial solution of ZC2403-SYL, ZC2404-SYT and ZC2402-MT:

[0128] The steps for mixed bacteria to quickly form sludge are as follows;

[0129] 1. Add inoculum sludge to the reactor, transport sewage from the bottom device, and add 1g / L ZC2403-SYL, ZC2404-SYT and ZC2402-MT mixed bacterial solution at one time. The temperature in the device is 33℃, the speed is maintained at 150rpm, the dissolved oxygen DO value is 4mg / L, and the pH is 7.5.

[0130] 2. Set the residence time to 24 hours and add nutrients and trace elements;

[0131] The dosage of nutrient elements is: NaCl 6%, NaHCO3 0.2%, MgSO4 0.05%, CaCl2 0.02%, yeast extract 0.01%, and the pH is maintained between 7.2-7.8;

[0132] The dosage of trace elements is: Fe 10mg / L, Cu 0.3mg / L, Mo 0.1mg / L, Zn 0.1mg / L, Co 0.1mg / L, Mn 0.1mg / L.

[0133] 3. Add ZC2403-SYL, ZC2404-SYT and ZC2402-MT mixed bacterial solution into the reactor by one-time addition. The temperature in the device is 33°C and the pH is controlled at 7.2.

[0134] The strain was inoculated into the sludge at a dosage of 10%, and the culture was rapidly expanded. The effective live bacteria count in the bacterial solution in the reactor could reach more than 109 / ml, and a mixed bacterial solution and bacterial agent of high-salt organic wastewater efficient degradation bacteria ZC2403-SYL, ZC2404-SYT and ZC2402-MT was obtained, which was named as high-salt organic wastewater efficient degradation bacterial agent ZC-SY, and can be used in subsequent wastewater treatment processes;

[0135] The reactor height to diameter ratio H / D is 5.

[0136] Example 8, application of high-salinity organic wastewater efficient degradation bacterial agent ZC-SY in actual high-salinity organic wastewater:

[0137] In order to further verify the application effect of the high-salt organic wastewater efficient degradation bacterial agent ZC-SY used in the present invention in actual high-salt organic wastewater, high-salt organic nitrogen wastewater was obtained from the production workshop of the desired pharmaceutical company;

[0138] After measurement, the organic nitrogen concentration in the wastewater is about 200 mg / L;

[0139] The high-salt organic wastewater efficient degradation bacterial agent ZC-SY obtained in Example 7 was directly added to the wastewater at an inoculation rate of 10%, and the pH of the system was adjusted to 7.2 to meet the needs of normal growth of microorganisms;

[0140] At room temperature, sample regularly at 0h, 16h, 24h, 48h, and 72h to monitor the changes in organic nitrogen in the system, such as Figure 5 As shown;

[0141] After 24 hours, the organic nitrogen concentration has dropped to 2 mg / L, and the rate of organic nitrogen released into ammonia nitrogen is as high as 99%. The above experimental data show that the high-salinity organic wastewater efficient degradation bacterial agent ZC-SY also has a good treatment effect in actual high-salinity organic wastewater and has broad application prospects.

[0142] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A biological treatment method for high-salt organic wastewater, characterized in that: The steps include: Step 1: Screening of halophilic bacteria: directly screen the desired halophilic bacteria from the soil of saline-alkali land, and then rescreen the mixed culture of bacteria obtained from the initial screening; Step 2, screening of salt-tolerant bacteria, where salt-tolerant bacteria are directly screened from pre-selected activated sludge, and then the mixed culture of bacteria obtained from the initial screening is rescreened; Step 3, separation and purification of strains, the mixed culture of the above-obtained bacterial flora is transferred to a high-salt organic medium at an inoculation rate of 2%, and the halophilic bacteria and the halotolerant bacteria are further streaked and purified by the plate streak method until a single colony grows; Step 4, identification of strains, the purified 2 halophilic bacteria and 1 halotolerant bacteria were sent to the assay site for 16S rRNA gene sequencing, and the sequencing results were compared with the nucleic acid sequences in the GenBank database.

2. A biological treatment method for high-salt organic wastewater according to claim 1, characterized in that: The screening method in the screening of the halophilic bacteria is as follows: The collected soil samples were made into a solution with PBS buffer solution, and oscillated on a shaker for 30 minutes to make a soil suspension. 100 mL of the mixed soil suspension was taken and added to 1 L of primary screening culture medium, followed by rescreening, and the addition amount was 1-3%.

3. A biological treatment method for high-salt organic wastewater according to claim 2, characterized in that: The primary screening culture medium is 30-60 g / L sodium chloride, 1 g / L glucose, 0.05 g / L nitrogen source, 0.001 g / L phosphorus source, and pH is between 7.2-7.8; Culture temperature: 33-37℃, aerobic culture; During the screening process, the COD concentration was monitored regularly. After 3-5 rounds of degradation, the inorganic salt concentration was gradually increased to 60-90 g / L. After another 3-5 rounds of degradation, a mixed culture of bacteria that could tolerate high-salt wastewater not exceeding 90 g / L was obtained.

4. The method for biological treatment of high-salt organic wastewater according to claim 1, characterized in that: The screening method in the screening of the salt-tolerant bacteria is as follows: The dosage of activated sludge during screening is 5g / L; The primary screening culture medium is 30-60g / L sodium chloride, 1g / L glucose, 0.05g / L nitrogen source, 0.001g / L phosphorus source, pH 7.2-7.

8. Culture temperature: 33-37 ℃, aerobic culture. In addition, during the screening process, the COD concentration is regularly monitored. After 3-5 rounds of degradation, the inorganic salt concentration is gradually increased to 60-90g / L. After another 3-5 rounds of degradation, a mixed culture of bacteria that can tolerate high-salt wastewater not exceeding 90g / L is obtained.

5. A biological treatment method for high-salt organic wastewater according to claim 4, characterized in that: The dosage during the rescreening process is 1-3%; The secondary screening medium is: 60-90g / L sodium chloride, 1g / L organic nitrogen, 0.02g / L phosphorus source, pH between 7.2-7.

8. Culture temperature: 33-37 ℃, aerobic culture.

6. A biological treatment method for high-salt organic wastewater according to claim 5, characterized in that: During the screening process, the concentration of total nitrogen, ammonia nitrogen, and ammonia nitrogen release need to be monitored regularly. After 3-5 rounds of degradation, the mixed culture of bacteria that can tolerate high-salt organic wastewater of no more than 90g / L must be obtained; Among them, the organic nitrogen in the re-screened culture medium are n-butylamine, formamide and triethylamine, all of which can be degraded.

7. The method for biological treatment of high-salt organic wastewater according to claim 1, characterized in that: The formula of the high-salt organic culture medium is: 30-60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter, n-butylamine: formamide: triethylamine = 1:1:1, 0.001 g / L phosphorus source, pH between 7.2-7.8; The culture was cultured at 33°C in a shaking incubator until the logarithmic phase, and the culture solution was diluted and spread on a high-salt organic solid culture medium using the dilution spread plate method.

8. A biological treatment method for high-salt organic wastewater according to claim 7, characterized in that: The high-salt organic solid culture medium comprises 30-60 g / L sodium chloride, 0.5 g / L peptone, 0.25 g / L yeast powder, 1 g / L organic matter (n-butylamine: formamide: triethylamine = 1:1:1), 0.001 g / L phosphorus source, 2% agar, and a pH between 7.2 and 7.

8. The culture medium is placed in a 33°C constant temperature incubator for 2-3 days.

9. The method for biological treatment of high-salt organic wastewater according to claim 1, characterized in that: During the purification, a single bacterial colony grown in a solid culture medium is isolated using an inoculation needle in an ultra-clean workbench.

10. A biological treatment method for high-salt organic wastewater according to claim 9, characterized in that: During the purification process, the operation was repeated for more than three times until the colonies grown on the plate had a single morphology, thereby obtaining two purified halophilic bacteria and one halotolerant bacteria.

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