A biochemical phosphorus removal process for lithium battery recovery wastewater

Abstract

The present invention discloses a biochemical phosphorus removal process for lithium battery recovery wastewater, comprising: before water inlet, adjusting the organic phosphorus concentration in the wastewater to 100-150mg / L, pH to 7.2-7.8, and dissolved oxygen to less than 0.5mg / L according to the characteristics of lithium battery recovery wastewater, so that the inlet meets the requirements of microbial degradation and performs an anaerobic phosphorus release process; adding efficient phosphorus removal bacteria, controlling pH and dissolved oxygen, controlling pH to 7.2-7.8, and dissolved oxygen to less than 4-6mg / L, and performing an aerobic biochemical phosphorus reduction process. Under the condition that the initial concentration of organic phosphorus is about 100mg / L, the release rate of organic phosphorus can reach 98% within 48h, and the effect is very significant. Also disclosed is a rapid expansion culture process of the strain, which is simple to operate, has a short production cycle, and low production cost, has practical application value, and has broad market prospects.

Description

Technical Field

[0001] The present invention relates to the field of environmental microorganisms, in particular to a biochemical phosphorus removal process for lithium battery recovery wastewater, a screening of an efficient organophosphorus degradation bacterium, and a microbial cultivation process. Background Art

[0002] Lithium-ion batteries, with their high energy density, compact size, lightweight, environmentally friendly, low self-discharge rate, and long service life, have been rapidly adopted in various electronic devices and have become the mainstream power battery in the new energy vehicle industry. With the continuous development of the new energy vehicle industry, the market demand for lithium-ion batteries continues to increase. However, the average lifespan of lithium-ion batteries is only 2-3 years, posing a significant challenge to the disposal of a large number of retired and waste lithium-ion batteries. Lithium-ion batteries contain abundant metal elements such as nickel, cobalt, manganese, and lithium. Their direct disposal not only wastes resources but also creates significant environmental pressures. In recent years, researchers both domestically and internationally have conducted extensive research on their recovery, leading to a boom in the recycling of used lithium-ion batteries.

[0003] Lithium-ion batteries typically consist of a positive electrode, separator, negative electrode, casing, and electrolyte. The nickel, cobalt, manganese, and lithium metals in the positive electrode and the electrolyte are the primary targets for recovery. Solvent extraction offers the advantages of ease of operation, low energy consumption, and excellent separation efficiency. The recovered nickel, cobalt, manganese, and lithium are of high purity. Solvent extraction is currently a common method for recovering metals from spent lithium-ion batteries. Weakly acidic extractants such as di(2-ethylhexyl)phosphoric acid (D2EHPA, also known as P204), bis(2,4,4-trimethylpentyl)phosphonic acid (Cyanex 272), 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC-88A, also known as P507), and tributyl phosphate (TBP) are commonly used. At the end of the recovery process, a large amount of extractant residue remains, generating residual extractant wastewater. Commonly used extractants are organophosphorus compounds, which are highly toxic and insoluble in water. Untreated or substandard treatment can have serious environmental impacts. For the treatment of lithium-ion battery recycling wastewater, finding a process that can efficiently degrade organic phosphorus in lithium battery recycling wastewater has become an effective approach.

[0004] Organophosphates are compounds containing carbon-phosphorus bonds or phosphate derivatives containing organic groups. Organophosphate wastewater is highly toxic and difficult to degrade. Once released into the environment, it can cause significant damage to the ecosystem. Most organisms cannot directly utilize organophosphates and must first use phosphatase to hydrolyze them into inorganic phosphorus.

[0005] Traditional biological phosphorus removal can be divided into two processes: anaerobic phosphorus release and aerobic phosphorus uptake. During the anaerobic phase, PABs release polyphosphates from their bodies and use their energy to accumulate simple organic matter, storing them as polyhydroxyalkanoates (PHAs). During the aerobic phase, PABs decompose the PABs synthesized in their bodies, releasing energy to form polyphosphate bonds within their cells. They also absorb excess soluble phosphates in the wastewater to synthesize polyphosphates, which are then stored in their bodies. This removes phosphorus from the water body through sludge discharge. Although traditional biological phosphorus removal methods are only effective for inorganic phosphate removal, it is worth noting that some microorganisms in sludge have the ability to decompose organic phosphorus into simple inorganic phosphorus, which is then absorbed and removed by PABs. Bioaugmentation by screening highly efficient strains for specific organophosphorus compounds can significantly improve organic phosphorus removal capacity. Biological methods are economical and have relatively mature operational management. Organophosphorus wastewater with complex pollutants and high concentrations can have a strong inhibitory effect on microbial growth, requiring pretreatment or long-term acclimatization before biological treatment can be performed.

[0006] Lithium battery recycling wastewater is a difficult-to-degrade organic phosphorus. Its presence in the wastewater will cause excessive total phosphorus emissions and is toxic to ordinary microorganisms. As a result, the current biochemical effect of lithium battery recycling wastewater is not obvious. In order to solve the shortcomings of the existing technology, this project provides a lithium battery recycling wastewater biochemical phosphorus removal process. By using microbial methods, a strain of bacteria that can effectively degrade organic phosphorus in lithium battery recycling wastewater is screened out. This can effectively solve the problem of treating organic phosphorus in lithium-ion battery recycling wastewater in practice, reduce water treatment costs, and improve water treatment efficiency. This project has practical application value and broad market prospects. Summary of the Invention

[0007] The present invention aims to provide a biochemical phosphorus removal process for lithium battery recycling wastewater and successfully obtain a bacterial strain that efficiently degrades organophosphorus in lithium battery recycling wastewater, providing an effective solution to the practical treatment of such lithium battery recycling wastewater. Furthermore, the present invention provides a fermentation process for rapidly cultivating bacteria that efficiently degrade organophosphorus in lithium battery recycling wastewater.

[0008] The technical solution of the present invention is:

[0009] A biochemical phosphorus removal process for lithium battery recovery wastewater, comprising:

[0010] (1) According to the characteristics of lithium battery recycling wastewater, before the water enters, the organic phosphorus concentration in the wastewater is adjusted to 100-150 mg / L, the pH is 7.2-7.8, and the dissolved oxygen is less than 0.5 mg / L, so that the water meets the requirements of microbial degradation;

[0011] (2) Add high-efficiency organophosphorus degrading bacteria, control the pH and dissolved oxygen content, control the pH to 7.2-7.8 and the dissolved oxygen to 4-6 mg / L, and carry out aerobic biochemical phosphorus removal process.

[0012] The selected high-efficiency organophosphorus-degrading bacteria are added to decompose the organic phosphorus in the wastewater into inorganic phosphorus. The polyphosphate bacteria absorb excessive soluble phosphates in the wastewater to synthesize polyphosphates and store them in the body, and then remove phosphorus from the water body in the form of sludge discharge (aerobic phosphorus absorption).

[0013] The lithium battery recovery wastewater is wastewater containing organic acid extractants such as di(2-ethylhexyl)phosphoric acid (P204) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507), and the organic phosphorus concentration is adjusted to 100-150 mg / L by dilution.

[0014] The dosage of ZC2303-LD, an efficient organophosphorus degrading bacteria, in lithium battery recovery wastewater is 5%-10%.

[0015] The high-efficiency organic phosphorus degrading bacteria used in the biochemical phosphorus removal of lithium battery recycling wastewater is classified and named as Acinetobacter venezuelae ( Acinetobacter venetianus ) ZC2303-LD was deposited in the General Microbiology Center of China Culture Collection Administration on August 17, 2023, with the deposit number: CGMCC No.28188.

[0016] Physiological characteristics are: the colonies are medium-sized, round, white, with a moist center and neat edges.

[0017] The strain ZC2303-LD was obtained by screening sludge from an aerobic tank at a Nanjing sewage treatment plant. It can tolerate lithium battery recovery wastewater solutions with an organic phosphorus concentration of no more than 200 mg / L. The microbial phosphorus removal process lasts 48-72 hours. The screening medium uses di(2-ethylhexyl) phosphate (P204) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507) as organic carbon sources. The medium consists of 0.5 g / L P204, 0.5 g / L P507, 0.5 g / L nitrogen source, and 2-10 g / L inorganic salts, with a pH between 7.2 and 7.8. The culture temperature is 33-37°C, and the culture is aerobic. The nitrogen source is ammonium chloride, and the inorganic salt is sodium chloride.

[0018] The organophosphorus-degrading bacteria ZC2303-LD provided by the present invention can grow using P204 and P507 as organic carbon sources. Under laboratory aeration treatment conditions, strain ZC2303-LD can achieve a degradation rate of 98% within 72 hours in self-prepared wastewater with an initial organophosphorus concentration of 150 mg / L. Furthermore, the strain ZC2303-LD has been verified for its effectiveness in treating organophosphorus wastewater from lithium battery recycling. When a 10% volume fraction of a bacterial inoculum fermented from ZC2303-LD was added to lithium battery recycling wastewater with an initial organophosphorus concentration of 100 mg / L, after 72 hours of aeration treatment, the degradation rate of organophosphorus reached 92%, demonstrating excellent results.

[0019] The present invention provides a process for simply and quickly cultivating and fermenting an organophosphorus-efficient degrading bacterium. The fermentation and expansion process includes the steps of activation, transfer, and expansion. The specific process flow is as follows:

[0020] S1 activation: Transfer a single colony of an organophosphorus-efficient degrading bacterium from a solid plate to a medium (5 mL) containing P204 or P507 as an organic carbon source, and culture at 33°C at a shaking speed of 100 rpm for 24-48 hours until the logarithmic phase.

[0021] S2 transfer: Transfer the organic phosphorus-degrading bacteria solution activated in the logarithmic phase in process 1 to a 500 mL seed tank at a 2-5% inoculation rate for cultivation. Maintain the temperature of the seed tank at 33°C, the rotation speed at 100 rpm, and the dissolved oxygen (DO) at 4-6 mg / L for 24-48 hours.

[0022] S3 expansion: The organophosphorus degrading bacterial solution cultured in the seed tank of process 2 is transferred to a 10L fermentation tank at an inoculation rate of 2%-5% for expansion culture. The composition of the fermentation tank culture medium is the same as that of the seed tank. The physical and chemical parameters are as follows: temperature 33°C, rotation speed 100rpm, dissolved oxygen 4-6mg / L, fermentation time 48-72h. After the fermentation is completed, the number of effective viable bacteria in the tank culture can reach 10 9 / ml or more, and the fermentation culture liquid can be packaged in plastic barrels after being taken out of the tank to obtain a highly efficient degradation bacterial agent for organic phosphorus in wastewater from the lithium battery recycling industry.

[0023] The strain of the present invention can grow using di(2-ethylhexyl) phosphate (P204) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507) as organic carbon sources. Preferably, the organic carbon source culture medium comprises: 0.5 g / L P204, 0.5 g / L P507, and a pH between 7.2 and 7.8. The culture temperature is 33-37°C, and the culture is aerobic.

[0024] The culture medium composition of the seed tank is (by weight): P2O4 0.05-0.1%, P5O7 0.05-0.1%, glucose 0.01-0.02%, NH4Cl 0.1-0.2%, MgSO4 0.025-0.05%, NaCl 0.01-0.02%, CaCO3 0.015-0.3%, NaHCO3 0.1-0.2%, and the balance is water. The pH is maintained between 7.2 and 7.8 by implementing automatic pH adjustment technology. More preferably, the pH is maintained between 7.2 and 7.8 by using P2O4 0.1%, P5O7 0.1%, glucose 0.02%, NH4Cl 0.2%, KH2PO4 0.01%, MgSO4 0.05%, NaCl 0.02%, CaCO3 0.3%, and NaHCO3 0.2%.

[0025] The invention discloses an application of the bacterial agent of the highly efficient organophosphorus degrading bacteria in degrading di(2-ethylhexyl)phosphoric acid (P204) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507) wastewater.

[0026] A bacterial agent for degrading P204 and P507 organic phosphorus pollutants with high efficiency, the bacterial agent is obtained by fermenting Acinetobacter venezuelae ( Acinetobacter venetianus )ZC2303-LD, after the fermentation culture liquid is taken out of the tank and packaged, you can get P204 and P507 organophosphorus wastewater efficient degradation bacteria agents.

[0027] The strain of the present invention can be used to treat recycled wastewater from the lithium battery industry. It is not limited to degrading P204 and P507, which are only representatives of recycled wastewater from the lithium battery industry. The strain of the present invention is aimed at degrading organic phosphorus in recycled wastewater from the lithium battery industry.

[0028] The application of the high-efficiency bacterial agent for degrading organophosphorus wastewater in the lithium battery recycling industry in degrading organophosphorus wastewater in the lithium battery recycling industry.

[0029] The application of the highly efficient organophosphorus degrading bacteria in the treatment of organophosphorus industrial wastewater in the lithium battery recycling industry.

[0030] Acinetobacter venezuelae ( Acinetobacter venetianus ZC2303-LD was cultured and added to lithium battery recycling wastewater to degrade organophosphorus. This strain can tolerate high concentrations of lithium battery recycling wastewater and has a high degradation rate.

[0031] The strain ZC2303-LD was inoculated into a reactor with sludge added, and the culture was rapidly expanded to obtain sludge that releases organic phosphorus in lithium battery recovery wastewater.

[0032] The strain ZC2303-LD was inoculated into a reactor containing sludge, and the trace elements Fe, Cu, Mo, Zn, Co, and Mn were added to the reactor. The mass ratio of these trace elements was: Fe 0-1 g / L, Cu 0-1 mg / L, Mo 0-1 mg / L, Zn 0-1 mg / L, Co 0-1 mg / L, and Mn 0-1 mg / L.

[0033] The reaction mechanism of the process of the present invention is as follows:

[0034] Phosphorus removal process using organophosphorus-degrading bacteria: Organophosphorus-degrading bacteria have the ability to decompose organic phosphorus into simple inorganic phosphorus, which is then absorbed and removed by polyphosphate bacteria. Polyphosphate bacteria decompose the PHAs synthesized in the body, releasing energy to form polyphosphate bonds in the cells, and excessively absorb soluble phosphates in the wastewater to synthesize polyphosphates and store them in the body, thereby removing phosphorus from the water body in the form of sludge discharge. Beneficial effects

[0035] (1) Under aerobic conditions, the influent concentration, dissolved oxygen concentration and pH of lithium battery recycling wastewater were regulated, and the strain ZC2303-LD was added for biological phosphorus removal. This was beneficial for first using biological enzymes to degrade organic phosphorus in lithium battery recycling wastewater at a low cost. Experimental verification showed that the release rate of organic phosphorus in lithium battery recycling wastewater could reach 92%, indicating an ideal treatment effect, simple operation, low investment and strong practicality.

[0036] (2) The strain of the present invention can tolerate a lithium battery recovery wastewater solution with an organic phosphorus concentration not exceeding 200 mg / L. After 48 hours of aerobic treatment, the organic phosphorus release rate in the lithium battery recovery wastewater can reach 92%. At the same time, the strain of the present invention can be expanded and cultured at the project site, and the cultured bacterial solution can be immediately added and used at the site of use, saving transportation costs and time costs, and avoiding the negative impact of long-term maintenance.

[0037] (3) The present invention provides the bacterial strain with the nutrients and space required for proliferation, thereby achieving on-site expansion of effective bacteria at the project site, ensuring effective connection between expansion and application, and ensuring the number of viable bacteria of effective microorganisms. The concentration of the organophosphorus-degrading bacteria expanded by the method of the present invention is about 50,000 bacteria per milliliter of bacterial liquid, and can also significantly reduce transportation costs and time costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The change curve of the strain ZC2303-LD on organic phosphorus in the wastewater of self-produced lithium battery recovery in Example 4;

[0039] Figure 2 The change curve of the strain ZC2303-LD in Example 5 on the organic phosphorus in actual lithium battery recovery wastewater. Implementation Method

[0040] The following examples are applicable to the present invention but are not intended to limit the scope of the invention. Unless otherwise specified, the technical means used in the examples are conventional means known to those skilled in the art. The activated sludge from the industrial wastewater treatment plant described in the examples was obtained from a biochemical pond in a sewage treatment plant in Jiangsu Province. Example 1

[0041] Isolation and purification of strain ZC2303-LD

[0042] (1) Acclimation and enrichment: 50 ml of activated sludge was added to a 1 L acclimation device containing a basic culture medium with di(2-ethylhexyl) phosphate (P204) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507) as the main carbon sources. The activated sludge was obtained from the biochemical pool of a sewage treatment plant in Jiangsu. The basic culture medium formula was: P204 0.5 g / L, P507 0.5 g / L, NH4Cl 0.5 g / L, MgCl2 0.02 g / L, CaCl2 0.03 g / L, and NaHCO3 0.5 g / L. The culture was aerated and acclimated for about 25-30 days. During this period, the COD concentration, orthophosphate release rate, and sludge growth were regularly monitored. After the COD degradation was detected to be complete, P204 and P507 were added in time, and the concentrations of the two were gradually increased to 2 g / L to obtain the enrichment solution of organophosphorus-degrading bacteria.

[0043] (2) Separation: Under sterile conditions, the acclimated enriched bacterial solution was transferred to a sterile fresh basal culture medium with 1-di(2-ethylhexyl) phosphate (P204) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507) as the main carbon sources at a 2% inoculation rate. The basal culture medium formula was the same as that in step 1. The culture was cultured in a shaking incubator at 33°C until the logarithmic phase. The culture was diluted and spread on a solid separation medium with di(2-ethylhexyl) phosphate (P204) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (P507) as the main carbon sources using the dilution spread plate method. The components of the solid separation medium were P204 0.5 g / L, P507 0.5 g / L, NH4Cl 0.5 g / L, MgCl2 0.02 g / L, CaCl2 0.03 g / L, NaHCO3 1 g / L, and agar 2%. Place in a 33°C constant temperature incubator and culture for 2-3 days.

[0044] (3) Purification: In a clean bench, use an inoculation needle to pick up a single colony grown in the solid culture medium for organophosphorus separation. Use the plate streak method to further purify and culture the organophosphorus-degrading bacteria until a single colony grows. Repeat this operation three or more times until the colonies grown on the plate have a single morphology. This will result in a purified strain of bacteria that is highly efficient in degrading organophosphorus pollutants in lithium battery recycling wastewater. Example 2

[0045] Identification of strains

[0046] The purified strain was sent to a sequencing company (Shanghai Lingen Biotechnology Co., Ltd.) 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 MEGA 5.0 software. The taxonomic status of the strain was finally determined. The identification result was Acinetobacter venezuelae ( Acinetobacter venetianus Its main physiological characteristics are: the colonies are medium-sized, round, white, with a moist center and neat edges. Example 3

[0047] Culture method of strain ZC2303-LD

[0048] The method for cultivating the highly efficient organophosphorus-releasing bacteria ZC2303-LD in lithium battery recycling wastewater comprises the following steps:

[0049] (1) Activation: Pick a single colony of lithium battery recovery organophosphorus wastewater degrading bacteria from the solid plate and transfer it to an organic carbon source culture medium (5 mL) containing the organophosphorus wastewater (self-prepared water, the main components are P204 0.1 g / L, P507 0.1 g / L), shake at 100 rpm, and culture at 33 °C until the logarithmic phase;

[0050] (2) Transfer: The organophosphorus-degrading bacterial solution activated in the logarithmic phase in process 1 was transferred to a 500 mL seed tank at a 5% access volume for cultivation. The temperature of the seed tank was maintained at 33 °C, the rotation speed was maintained at 100 rpm, the dissolved oxygen (DO) was controlled at 4-6 mg / L, and the culture was carried out for 36 h.

[0051] (3) Expansion culture: The organic phosphorus 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 (P204 0.1%, P507 0.1%, glucose 0.02%, NH4Cl 0.2%, KH2PO4 0.01%, MgSO4 0.05%, NaCl 0.02%, CaCO3 0.3%, NaHCO3 0.2%, pH maintained between 7.2-7.8). The physical and chemical parameters were as follows: temperature 33°C, rotation speed 100 rpm, dissolved oxygen 8 mg / L, and fermentation time 36 h. After fermentation, the number of effective viable bacteria in the tank culture solution could reach 10 9 After the fermentation culture liquid is taken out of the tank and packaged in a plastic barrel, a lithium battery recovery and efficient degradation bacterial agent for organic phosphorus wastewater can be obtained. Example 4

[0052] Experimental study on the degradation of organophosphorus in wastewater from self-prepared lithium battery recycling by strain ZC2303-LD

[0053] Pick the purified Acinetobacter venezuelae ( Acinetobacter venetianus ) ZC2303-LD single colony was cultured in a shake flask containing an organic carbon source medium containing 0.5 g / L organic phosphorus (100 mL system, total phosphorus / inorganic phosphorus concentration 100 mg / L). The medium formula included: P204 0.5 g / L, P507 0.5 g / L, NH4Cl 0.5 g / L, MgCl2 0.02 g / L, CaCl2 0.03 g / L, and NaHCO3 0.5 g / L. The shaker speed was 100 rpm and the temperature was 33 ° C. The total phosphorus and inorganic phosphorus concentrations were measured at 0 h, 16 h, 24 h, 48 h, and 72 h, and the difference between the two was the organic phosphorus concentration. After 72 h of culture, the organic phosphorus was reduced to 0.5 mg / L, achieving complete release ( Figure 1 ).

[0054] Total phosphorus concentration determination method: potassium persulfate digestion method, specific experimental method, take several 50ml stoppered colorimetric tubes, add 0, 0.02, 0.04, 0.12, 0.28, 0.40, 0.60mg / L phosphate standard working solution, add water to 25mL, add 4mL of potassium persulfate solution, wrap a small piece of gauze around the tube mouth after stoppering and tie it tightly with thread to prevent the glass stopper from being rushed out during heating. Place the stoppered graduated tube in a large beaker and heat it in a sterilizer (pressure 1.1 kg / cm 2 After 30 minutes at 120°C (120°C), wait until the pressure gauge pointer drops to zero, remove and allow to cool. After cooling, dilute to 50ml with ultrapure water. Add 1ml of 10% ascorbic acid to the colorimetric tube and mix thoroughly. After 30 seconds, add 2ml of molybdate solution and mix thoroughly. Allow to stand for 15 minutes for color development. Measure absorbance at 700nm using a 10mm cuvette, using the zero-concentration solution as a reference.

[0055] Inorganic phosphorus concentration determination method: Molybdenum antimony spectrophotometry. Specific experimental procedures: Take several 50ml stoppered colorimetric tubes and add 0, 0.02, 0.04, 0.12, 0.28, 0.40, and 0.60 mg / L phosphate standard working solution, respectively. Add water to 50ml. Add 1ml of 10% ascorbic acid to the colorimetric tube and mix thoroughly. After 30 seconds, add 2ml of molybdate solution and mix thoroughly. Allow to stand for 15 minutes for color development. Measure the absorbance at 700nm using a 10mm cuvette, using the zero concentration solution as the reference. Example 5

[0056] Application of strain ZC2303-LD in actual lithium battery recycling wastewater

[0057] In order to further verify the Acinetobacter venezuelae used in the present invention ( Acinetobacter venetianus ) The application effect of ZC2303-LD in actual lithium battery recycling wastewater was obtained from the production workshop of a lithium battery recycling company. After measurement, the organic phosphorus concentration in the wastewater was about 100 mg / L. We cultured the Venetian acinetobacter ( Acinetobacter venetianus ) ZC2303-LD bacterial solution was directly added to the wastewater at a 10% inoculum volume, and the pH of the system was adjusted to 7.2 to meet the needs of normal microbial growth. Under room temperature conditions, samples were taken regularly at 0h, 16h, 24h, 48h, and 72h to monitor the changes in total phosphorus in the system ( Figure 2 After 24 hours, the concentration of organic phosphorus has dropped to 1 mg / L, and the rate of organic phosphorus release into orthophosphate is as high as 99%. The above experimental data show that Acinetobacter venezuelae ( Acinetobacter venetianus )ZC2303-LD also has a good treatment effect in actual lithium battery recovery wastewater and has broad application prospects.

Claims

1. A biochemical phosphorus removal process for lithium battery recovery wastewater, characterized in that: The steps include: (1) According to the characteristics of lithium battery recycling wastewater, before the water enters, the organic phosphorus concentration in the wastewater is adjusted to 100-150 mg / L, the pH is 7.2-7.8, and the dissolved oxygen is less than 0.5 mg / L, so that the water meets the requirements of microbial degradation; (2) Adding high-efficiency organic phosphorus degradation bacteria, controlling pH and dissolved oxygen, controlling pH to 7.2-7.8 and dissolved oxygen to 4-6 mg / L, and performing aerobic biochemical degradation and phosphorus removal process; the high-efficiency organic phosphorus degradation bacteria is Acinetobacter venezuelae ( Acinetobacter venetianus )ZC2303-LD has been deposited in the General Microbiology Center of China Culture Collection Administration of Microorganisms with the deposit number: CGMCC No.28188.

2. The biochemical phosphorus removal process for lithium battery recovery wastewater according to claim 1, characterized in that: In step (2), the aerobic biochemical treatment is carried out for 72 hours.

3. The biochemical phosphorus removal process for lithium battery recovery wastewater according to claim 1, characterized in that: In step (2), the dosage of the highly efficient organophosphorus degrading bacteria ZC2303-LD is 5%-10%.

4. A highly efficient organophosphorus degrading bacterium, which is classified as Acinetobacter venezuelae ( Acinetobacter venetianus )ZC2303-LD has been deposited in the General Microbiology Center of China Culture Collection Administration of Microorganisms with the deposit number: CGMCC No. 28188.

5. Use of the high-efficiency organophosphorus degrading bacteria according to claim 4 in degrading lithium battery recovery wastewater.

6. The use according to claim 5, characterized in that After culturing, the strain ZC2303-LD was added to the lithium battery recovery wastewater to be treated to release the organic phosphorus therein.

7. The use according to claim 6, characterized in that The culture method of the strain ZC2303-LD is as follows: a single colony is picked and placed in a culture medium containing di(2-ethylhexyl)phosphate and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester as organic carbon sources, cultured to the logarithmic phase, and then transferred to a seed tank for culture for 24-48 hours, and finally transferred to a fermentation tank for expansion culture for 48-72 hours to obtain a large amount of bacterial enrichment liquid.

8. The use according to claim 5, characterized in that The strain ZC2303-LD was inoculated into a reactor with sludge added, and the culture was rapidly expanded to obtain sludge that releases organic phosphorus in lithium battery recovery wastewater.

9. The use according to claim 8, characterized in that: The strain ZC2303-LD was inoculated into a reactor containing sludge, and trace elements Fe, Cu, Mo, Zn, Co, and Mn were added into the reactor.

10. The use according to claim 9, characterized in that: The mass ratio of the trace elements is: Fe 0~1mg / L, Cu 0~1mg / L, Mo 0~1mg / L, Zn 0~1mg / L, Co 0~1mg / L, Mn 0~1mg / L.

Images