Phycomycete symbiotic system and application of phycomycete symbiotic system in accelerating iron biological mineralization in acid mine wastewater

Abstract

The invention discloses a phycomycete symbiotic system and application of the phycomycete symbiotic system in accelerating iron biological mineralization in acid mine wastewater, and belongs to the technical field of acid mine wastewater treatment. AH02 and Acidithiobacillus ferrooxidans LX5 are synchronously inoculated, a phycomycete co-living reaction system is formed under the conditions of a small amount of nutritional agents, illumination, oxygenation and the like, and the phycomycete co-living activity reaction system can be used for preparing the phycomycete co-living activity reaction system on the basis of the dual effects of electron shuttling of algae source organic matter and seed crystal template regulation and control of algae cells, so that the application range of the phycomycete co-living activity reaction system is widened, and the application range of the phycomycete co-living activity reaction system is widened. And the application range of the phycomycete co-living activity reaction system is widened, and the application range of the phycomycete co-living activity reaction system is widened. According to the method, high-concentration soluble Fe (II) in the acidic mine water is quickly oxidized into Fe (III), and Fe (III) is quickly hydrolyzed into hydroxyl ferric sulfate minerals, so that the biological mineralization efficiency of Fe is greatly improved, and green and efficient treatment of the acidic mine wastewater is facilitated.

Description

Technical Field

[0001] The present application belongs to the technical field of acid mine wastewater treatment, and specifically relates to an algae-bacteria symbiotic system and its application in accelerating iron biomineralization in acid mine wastewater. Background Art

[0002] Acid mine drainage (AMD) is wastewater produced by chemical and biological oxidation of sulfide minerals such as pyrite (FeS2) in waste ore and tailings piles exposed to air during metal mining. AMD is reddish brown in appearance, with a pH value of 2.0 to 4.0, and contains a large amount of soluble iron (200 to 2000 mg / L) and heavy (class) metals such as copper, manganese, and arsenic (10 to 100 mg / L). Effective management of AMD is a global environmental issue.

[0003] Biomineralization based on Acidithiobacillus ferrooxidans (Af) is considered to be a green and low-carbon AMD treatment technology with great application prospects. It mainly converts the high concentration of soluble Fe in AMD into hydroxyferric sulfate minerals (Fe8O8(OH)6SO4, etc.) through Af biological oxidation of Fe(II) and Fe(III) hydrolysis precipitation for removal, and then only a small amount of lime is needed for neutralization to achieve AMD emission standards (adjusting pH value and removing other toxic metals). Compared with traditional AMD treatment technologies (such as direct lime neutralization precipitation, electrodialysis, and sulfate reduction), Af biomineralization has technical advantages such as a wide range of water quality applications, low treatment costs, and less toxic metal sediment production.

[0004] However, according to existing research practices, the biomineralization induced by Acidithiobacillus ferrooxidans Af in the actual AMD treatment process generally has bottleneck problems such as slow Fe(II) oxidation rate and low Fe(III) hydrolysis mineralization efficiency. This is because: on the one hand, Af is an inorganic chemolithoautotrophic microorganism, and its growth and reproduction rate is very slow, resulting in the complete oxidation of Fe(II) in AMD (Fe 2+ →Fe 3+ ) often takes a long time; on the other hand, under acidic conditions of normal temperature and pressure, the Fe(III) hydrolysis mineralization reaction (Fe 3+ →Fe8O8(OH)6SO4) Gibbs free energy (Δ r G ° 298 ) is high, especially in the nucleation stage, which results in about 50% of the soluble Fe in AMD being unable to be mineralized, affecting the efficiency of lime neutralization and secondary treatment and the final effluent quality.

[0005] Therefore, there is an urgent need to develop a new method that can accelerate the efficient biomineralization of soluble iron in acidic mine drainage. Summary of the invention

[0006] 1. Problem to be solved

[0007] The present application aims at the problems of slow Fe(II) oxidation rate and low Fe(III) hydrolysis mineralization efficiency in the existing Acidithiobacillus ferrooxidans Af bio-mineralization treatment technology for AMD, and provides an algae-bacteria symbiotic system and its application in accelerating iron bio-mineralization, especially for accelerating iron bio-mineralization in acid mine wastewater. The method is to use the algae-bacteria symbiotic system formed by acidithiobacillus ferrooxidans Af and acidophilic algae, especially Parachlorella sp. AH02 used in the present application to treat AMD, accelerate iron bio-mineralization, improve Fe(II) oxidation rate and Fe(III) hydrolysis mineralization efficiency, and realize the green and efficient conversion of high-concentration soluble iron in AMD into ferric hydroxysulfate.

[0008] 2. Technical solution

[0009] In order to solve the above problems, the technical solutions adopted in this application are as follows:

[0010] The present application provides an algae-bacteria symbiotic system, which includes acidophilic ferrothiobacillus and acidophilic algae. The algae-bacteria symbiotic system is formed by synchronously inoculating the two into a culture solution or wastewater system. In the symbiotic system, algae and bacteria achieve common survival and reproduction through the exchange of nutrients and metabolites and mutual influence.

[0011] Furthermore, the above-mentioned acidithiobacillus ferrooxidans is Acidithiobacillus ferrooxidans LX5, which is deposited in the General Microbiology Center of China National Committee for the Administration of Microbiological Culture Collection on March 13, 2002, with a deposit number of CGMCCNO.0727. The microorganism was previously screened and deposited by the inventor, as detailed in the Chinese invention patent publication number CN1375553A. LX5 was originally classified as Thiobacillus ferrooxidans, but with the development of microbial taxonomy, the understanding of this type of bacteria has become more in-depth, and it has been reclassified into the genus Acidithiobacillus, called Acidithiobacillus ferrooxidans.

[0012] Furthermore, the above-mentioned acidophilic algae is Parachlorella sp. AH02, which is deposited in the General Microbiology Center of the China Culture Collection Administration, with a preservation date of June 5, 2023 and a preservation number of CGMCCNO.40698. The microorganism was screened and preserved by the inventor in acidic mine wastewater in the early stage. For details, see the Chinese invention patent with publication number CN118084206A.

[0013] The present application also provides the application of the above-mentioned algae-bacteria symbiotic system in accelerating the biological mineralization of iron in acidic mine wastewater.

[0014] Furthermore, the above applications include:

[0015] S1, Acidithiobacillus ferrooxidans and acidophilic algae are inoculated into acid mine wastewater simultaneously; the two form an algae-bacteria symbiotic system;

[0016] S2, adding nutrients; the nutrients are used for the growth and proliferation of Acidithiobacillus ferrooxidans and / or Acidophilic algae;

[0017] S3, the acid mine wastewater is placed under light conditions for iron biomineralization. After static precipitation, hydroxysulfate iron minerals and treated wastewater can be obtained; in the process of acidic mine wastewater oxidation of Fe(II) by Acidithiobacillus ferrooxidans, organic matter with high electron transfer ability (such as proteins, phospholipids, unsaturated hydrocarbons, etc.) carried or secreted by acidophilic algae acts as an electron shuttle to accelerate the electron transfer between Fe(II) and Acidithiobacillus ferrooxidans, and accelerate the production of reactive oxygen (H2O2 and ·OH, etc.) for the oxidation of Fe(II); in the process of Fe(III) hydrolysis and precipitation, algal cells play the role of seed crystal template regulation, accelerating the heterogeneous nucleation and crystal growth of Fe(III) minerals; under the dual action, Fe(II) in AMD can be oxidized to Fe(III) more quickly, and Fe(III) can also be hydrolyzed and mineralized more quickly, and the efficiency of iron biomineralization in AMD is greatly improved.

[0018] Furthermore, in the above application, the inoculation density of Acidithiobacillus ferrooxidans is 1×10 7 ~1×10 9 Pieces / mL.

[0019] Furthermore, in the above application, the inoculation density of acidophilic algae is 1×10 6 ~1×10 8 Pieces / mL.

[0020] Furthermore, in the above application, the nutrient agent includes any one or more of NaNO3, K2HPO4, MgSO4·7H2O, CaCl2·2H2O, NaCO3, propionic acid, and citric acid.

[0021] Furthermore, the above-mentioned nutrient agent includes (g / L): any one or more of NaNO3 0.1-1.5, K2HPO4 0.01-0.04, MgSO4·7H2O0.01-0.075, CaCl2·2H2O 0.01-0.036, NaCO3 0.01-0.02, propionic acid 0.01-0.2, and citric acid 0.001-0.01.

[0022] Furthermore, in the above application, the illumination conditions include: illumination intensity 0.2 to 2 mW / cm 2 .

[0023] Furthermore, in the above application, the iron biomineralization conditions include: 6 to 8 hours at 15 to 35°C.

[0024] The present application also provides a method for accelerating the biological mineralization of iron in acidic mine wastewater. The method is to form an algae-bacteria symbiotic system in the acidic mine wastewater. The algae-bacteria symbiotic system includes acidophilic ferrooxidans and acidophilic algae. The algae-bacteria symbiotic system is formed by synchronously inoculating the two into a culture solution or wastewater system.

[0025] Furthermore, the above-mentioned Acidithiobacillus ferrooxidans is Acidithiobacillus ferrooxidans LX5, which is deposited in the General Microbiological Center of China National Committee for the Preservation of Microorganisms on March 13, 2002, with a deposit number of CGMCCNO.0727.

[0026] Furthermore, the above-mentioned acidophilic algae is Parachlorella sp. AH02, which is deposited in the General Microbiology Center of China National Microbiological Culture Collection Administration, with a deposit date of June 5, 2023 and a deposit number of CGMCCNO.40698.

[0027] Furthermore, the above method for accelerating iron biomineralization in acid mine wastewater specifically comprises the following steps:

[0028] M1, Acidithiobacillus ferrooxidans and acidophilic algae were inoculated into acid mine wastewater simultaneously; the two formed an algae-bacteria symbiotic system;

[0029] M2, adding nutrients; the nutrients are used for the growth and proliferation of Acidithiobacillus ferrooxidans and / or Acidophilic algae;

[0030] M3, the acid mine drainage water is placed under light conditions for iron biomineralization. After static precipitation, hydroxy iron sulfate minerals and treated wastewater can be obtained.

[0031] Furthermore, the inoculation density of the above-mentioned Acidithiobacillus ferrooxidans is 1×10 7 ~1×10 9 Pieces / mL.

[0032] Furthermore, the inoculation density of the acidophilic algae is 1×10 6 ~1×10 8 Pieces / mL.

[0033] Furthermore, the above-mentioned nutrient includes any one or more of NaNO3, K2HPO4, MgSO4·7H2O, CaCl2·2H2O, NaCO3, propionic acid, and citric acid.

[0034] Furthermore, the above-mentioned nutrient agent includes (g / L): any one or more of NaNO3 0.1-1.5, K2HPO4 0.01-0.04, MgSO4·7H2O0.01-0.075, CaCl2·2H2O 0.01-0.036, NaCO3 0.01-0.02, propionic acid 0.01-0.2, and citric acid 0.001-0.01.

[0035] Furthermore, the above-mentioned illumination conditions include: illumination intensity 0.2-2 mW / cm 2 .

[0036] Furthermore, the above-mentioned iron biogenic mineralization conditions include: 6 to 8 hours at 15 to 35°C.

[0037] The present application also provides the application of the above-mentioned algae-bacteria symbiotic system in treating acidic mine wastewater.

[0038] The present application also provides the application of the above-mentioned method for accelerating iron biomineralization in acidic mine drainage water in treating acidic mine drainage water.

[0039] The present application provides the application of the above-mentioned method of accelerating iron biomineralization in acidic mine drainage water by using an algae-bacteria symbiotic system in treating acidic mine drainage water.

[0040] The present application also provides a process for treating acid mine wastewater, the process comprising:

[0041] N1, Acidithiobacillus ferrooxidans and Acidophilus algae were inoculated into acid mine drainage simultaneously;

[0042] N2, adding nutrients;

[0043] N3, placing the acid mine drainage water under light conditions for iron biomineralization, and obtaining treated wastewater after static sedimentation;

[0044] N4, add alkaline substances to the treated wastewater to adjust the pH and obtain the final effluent.

[0045] Furthermore, the above-mentioned Acidithiobacillus ferrooxidans (Af) is Acidithiobacillus ferrooxidans LX5, which was deposited in the General Microbiological Center of China National Microbiological Culture Collection Administration on March 13, 2002, with a deposit number of CGMCC NO.0727.

[0046] Furthermore, the above-mentioned acidophilic algae is Parachlorella sp. AH02, which is deposited in the General Microbiology Center of China National Microbiological Culture Collection Administration, with a deposit date of June 5, 2023 and a deposit number of CGMCCNO.40698.

[0047] Furthermore, the inoculation density of the above-mentioned Acidithiobacillus ferrooxidans is 1×10 7 ~1×10 9 .

[0048] Furthermore, the inoculation density of the acidophilic algae is 1×10 6 ~1×10 8 Pieces / mL.

[0049] Furthermore, the above-mentioned nutrient includes any one or more of NaNO3, K2HPO4, MgSO4·7H2O, CaCl2·2H2O, NaCO3, propionic acid, and citric acid.

[0050] Furthermore, the above-mentioned nutrient agent includes (g / L): any one or more of NaNO3 0.1-1.5, K2HPO4 0.01-0.04, MgSO4·7H2O0.01-0.075, CaCl2·2H2O 0.01-0.036, NaCO3 0.01-0.02, propionic acid 0.01-0.2, and citric acid 0.001-0.01.

[0051] Furthermore, the above-mentioned illumination conditions include: illumination intensity 0.2-2 mW / cm 2 .

[0052] Furthermore, the above-mentioned illumination conditions include: illumination intensity 1.5 mW / cm 2 .

[0053] Furthermore, the above-mentioned illumination conditions include: illumination intensity 2mW / cm 2 .

[0054] Furthermore, the above-mentioned iron biogenic mineralization conditions include: 6 to 8 hours at 15 to 35°C.

[0055] Furthermore, the alkaline substance includes lime.

[0056] Furthermore, the pH is adjusted to 7.0-7.5.

[0057] 3. Beneficial effects

[0058] Compared with the prior art, the present application has the following beneficial effects:

[0059] (1) The present application provides an algae-bacteria symbiotic system and its application in accelerating the biological mineralization of iron in acidic mine wastewater. By synchronously inoculating acidithiobacillus ferrooxidans (Af) and acidophilic algae Parachlorella sp. AH02, the two form an algae-bacteria symbiotic system. In acidic mine wastewater, the algae-bacteria symbiotic system, on the one hand, accelerates the electron transfer between Fe(II) and Af through organic matter (proteins, phospholipids, unsaturated hydrocarbons, etc.) with high electron transfer ability carried or secreted by acidophilic algae as electron shuttles, accelerates the production of reactive oxygen (H2O2 and ·OH, etc.) for the oxidation of Fe(II); on the other hand, the algal cells of acidophilic algae can be used as seed crystal templates to accelerate the heterogeneous nucleation and crystal growth of Fe(III) minerals; under the combined action of the above two aspects, Fe(II) in AMD is rapidly oxidized to Fe(III) and Fe(III) is rapidly hydrolyzed to mineralize, thereby greatly improving the efficiency of biological mineralization of soluble iron in AMD. Compared with the existing AMD iron biomineralization treatment based on Acidithiobacillus ferrooxidans, this method effectively solves the problems of slow Fe(II) oxidation rate and low Fe(III) hydrolysis mineralization efficiency, and the wastewater treatment efficiency is significantly improved.

[0060] (2) The present application provides an algae-bacteria symbiotic system and its application in accelerating the biological mineralization of iron in acidic mine wastewater. The acidophilic algae is Parachlorella sp. AH02, and the acidophilic ferrooxidans is Acidithiobacillus ferrooxidans LX5, both of which are isolated from acidic mine wastewater. Both are indigenous microorganisms with strong environmental adaptability. The nutrients required for their growth are widely available, cheap and easy to obtain.

[0061] (3) The present application provides an algae-bacteria symbiotic system and its application in accelerating the biological mineralization of iron in acidic mine wastewater, which is used to treat acidic mine wastewater. The treatment process of the entire algae-bacteria symbiotic system is simple, easy to operate, green and efficient, and economical and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1It is a process flow chart of algae-fungus symbiotic biomineralization for treating acidic mine wastewater.

[0063] Figure 2 Soluble Fe(II) concentration (a), Fe mineral yield (b), microstructure (c) and XRD identification (d) during the algae-fungus symbiotic biomineralization process for acid mine drainage treatment.

[0064] Figure 3 It is the change in the appearance of water quality before and after the algae-fungus symbiotic biomineralization treats acid mine drainage. DETAILED DESCRIPTION

[0065] The present application is further described below in conjunction with specific embodiments.

[0066] It should be noted that the terms such as "upper", "lower", "left", "right", "middle", etc. cited in this specification are only for the convenience of description and are not used to limit the scope of implementation. Changes or adjustments to their relative relationships should be regarded as the scope of implementation of this application without substantially changing the technical content.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0068] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0069] As used herein, the term "about" is used to provide flexibility and imprecision associated with a given term, measurement or value. The degree of flexibility for a particular variable can be easily determined by one skilled in the art.

[0070] As used herein, the term "at least one of" is intended to be synonymous with "one or more of." For example, "at least one of A, B, and C" expressly includes only A, only B, only C, and combinations of each thereof.

[0071] Concentration, amount and other numerical data can be presented in range format herein.It should be understood that such range format is only used for convenience and simplicity, and should be flexibly interpreted as not only including the numerical value clearly described as range limit, but also including all single numerical values ​​or sub-ranges contained in the range, just as each numerical value and sub-range are clearly described.For example, the numerical range of about 1 to about 4.5 should be interpreted as not only including the limit value of 1 to about 4.5 clearly described, but also including single numerals (such as 2,3,4) and sub-ranges (such as 1 to 3,2 to 4, etc.).The same principle is applicable to the scope of only narrating a numerical value, such as "less than about 4.5", which should be interpreted as including all the above-mentioned values ​​and ranges.In addition, no matter how the breadth of the described range or feature is, this explanation should be applicable.

[0072] As used herein, "algae" refers to a group of thallus plants that have no differentiation of roots, stems, leaves, vascular tissue, zygotes that do not develop into embryos, reproductive organs that are single-celled, contain photosynthetic pigments, are photoautotrophic, and produce oxygen. It includes eukaryotic algae and prokaryotic algae. Most species live in water.

[0073] In the present application, "simultaneous inoculation" refers to the process of inoculating two or more different microorganisms into the same culture system or environment at the same time point or within a very close time interval.

[0074] Example 1

[0075] This embodiment provides an algae-bacteria symbiotic system and its application in accelerating iron biomineralization in acid mine wastewater.

[0076] In this embodiment, the algae-bacteria symbiotic system includes Acidithiobacillus ferrooxidans and Acidophilic algae, and the algae-bacteria symbiotic system is formed by synchronously inoculating the two into a culture medium or wastewater system. In the symbiotic system, algae and bacteria achieve common survival and reproduction through the exchange of nutrients and metabolites and mutual influence.

[0077] In this embodiment, Acidithiobacillus ferrooxidans (Af) is Acidithiobacillus ferrooxidans LX5, which was deposited in the General Microbiological Center of China National Microbiological Culture Collection Administration on March 13, 2002, with a deposit number of CGMCC NO.0727.

[0078] In this embodiment, the acidophilic algae is Parachlorella sp. AH02, which is deposited in the General Microbiology Center of the China Culture Collection Administration, with a deposit date of June 5, 2023, a deposit number of CGMCCNO.40698, and a deposit address of the Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0079] In this embodiment, the algae-bacteria symbiotic system is used to accelerate the biological mineralization of iron in acid mine drainage, including:

[0080] Acidithiobacillus ferrooxidans and acidophilic algae were inoculated into acid mine drainage simultaneously;

[0081] Add nutrients;

[0082] Iron biomineralization of acid mine drainage under light conditions.

[0083] In this embodiment, the algae-bacteria symbiosis system is used to treat acid mine drainage. The algae-bacteria symbiosis accelerates the biological mineralization of iron in the acid mine drainage and removes iron from the acid mine drainage. The process is as follows: Figure 1 As shown, including:

[0084] Acidithiobacillus ferrooxidans and acidophilic algae were inoculated into acid mine drainage simultaneously;

[0085] Add nutrients;

[0086] The acid mine wastewater is placed under light conditions for iron biomineralization, and after static precipitation, the treated wastewater is obtained;

[0087] Alkaline substances (lime) are added to the treated wastewater to adjust the pH to 7.0-7.5 to obtain the final effluent.

[0088] In this embodiment, the water sample is mine water from an iron ore mine in Maanshan, Anhui Province, with a pH value of 2.7, a soluble Fe(II) content of 615 mg / L, and heavy metal ion Mn, Cu, Zn, and Ni contents of 393 mg / L, 37 mg / L, 36 mg / L, and 3 mg / L, respectively.

[0089] In this embodiment, the algae-bacteria symbiosis system is used to treat acid mine drainage water, and the iron biomineralization in the acid mine drainage water is accelerated by algae-bacteria symbiosis, and the iron in the acid mine drainage water is removed, which specifically includes:

[0090] Inoculation: Add algae to the water sample at a density of 1×10 7 / mL of Parachlorella sp. AH02 and bacterial density 5×10 7Acidithiobacillus ferrooxidans LX5 per mL;

[0091] Add nutrients: 0.5g / L NaNO3;

[0092] Biomineralization treatment: 1.5mW / cm 2 The treatment was carried out under light and 18℃ for 8h. The electron accepting capacity and electron donating capacity of the treatment system were 0.9mmol e - / g C (-0.45V) and 0.7mmol e - / g C (0.61V); liquid chromatography detection showed that the cumulative concentration of hydroxyl radicals ·OH reached 25μM; analysis of the treated water samples found that the pH value of the solution was 2.1 and the Fe(II) content was reduced to 22mg / L ( Figure 2 a), and a large amount of reddish brown precipitate was produced ( Figure 2 b); SEM and XRD tests showed that the precipitate produced had a burr-like appearance ( Figure 2 c), chemical composition is hydroxy iron sulfate mineral ( Figure 2 middle d);

[0093] Solid-liquid separation: The water sample after biomineralization treatment was allowed to settle, and lime was added to the supernatant to adjust the pH to 7.5 to obtain the final effluent ( Figure 3 ); After ICP testing, the heavy metal concentration in the effluent meets the discharge requirements.

[0094] Example 2

[0095] This embodiment provides an algae-bacteria symbiotic system and its application in accelerating iron biomineralization in acid mine wastewater.

[0096] In this embodiment, the water sample is acid water from a natural mine lake in Liuhe, Nanjing, with a pH of 2.5, a soluble Fe(II) content of 1080 mg / L, and heavy metal ion Mn and Zn contents of 45 mg / L and 37 mg / L, respectively.

[0097] In this embodiment, Acidithiobacillus ferrooxidans (Af) is Acidithiobacillus ferrooxidans LX5, which was deposited in the General Microbiological Center of China National Microbiological Culture Collection Administration on March 13, 2002, with a deposit number of CGMCC NO.0727.

[0098] In this embodiment, the acidophilic algae is Parachlorella sp. AH02, which is deposited in the General Microbiology Center of the China Culture Collection Administration, with a deposit date of June 5, 2023, a deposit number of CGMCCNO.40698, and a deposit address of the Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0099] In this embodiment, the algae-bacteria symbiosis system is used to treat acid mine drainage water, and the iron biomineralization in the acid mine drainage water is accelerated by algae-bacteria symbiosis, and the iron in the acid mine drainage water is removed, which specifically includes:

[0100] Inoculation: Add algae to the water sample at a density of 3×10 6 cells / mL of Parachlorella sp. AH02 and a bacterial density of 2×10 8 Acidithiobacillus ferrooxidans LX5 per mL;

[0101] Add nutrients: 0.01g / LNaCO3 0.02, 0.02g / L propionic acid;

[0102] Biomineralization treatment: 2mW / cm 2 The treatment was carried out under light and 28℃ for 24h. The electron accepting capacity and electron donating capacity of the algae-derived organic matter in the treatment system were 0.25mmol e - / g C and 0.32mmole - / g C; liquid chromatography detection showed that the cumulative concentration of H2O2 reached 37μM; analysis of the treated water sample showed that the soluble Fe(II) content was reduced to 45mg / L, and a large amount of reddish brown precipitate was produced; XRD detection showed that the precipitate was hydroxysulfate iron ore;

[0103] Solid-liquid separation: The water sample after biomineralization treatment is allowed to settle, and lime is added to the supernatant to adjust the pH to 7.0 to obtain the final effluent.

[0104] Comparative Example 1

[0105] This comparative example provides the use of only adding Acidithiobacillus ferrooxidans LX5 in the biological mineralization and iron removal of acid mine wastewater, that is, no acidophilic algae - Parachlorella sp. AH02 is added.

[0106] With reference to Example 1,

[0107] The water sample is the acid mine wastewater in Example 1, and the specific steps are as follows:

[0108] Inoculation: Add bacteria at a density of 5×10 7 Acidithiobacillus ferrooxidansLX5 per mL;

[0109] Add nutrients: 0.5g / L NaNO3;

[0110] Biomineralization treatment: 1.5mW / cm 2 The treatment was carried out under light and 18℃ for 8h. During the whole treatment process, no current signal was detected. The cumulative concentration of hydroxyl radicals was 10μM. Analysis of the treated water samples showed that the pH value of the solution was 2.4 and the Fe(II) content was reduced to 126mg / L ( Figure 2 a), a certain amount of red-brown precipitate was produced ( Figure 2 b); SEM and XRD tests showed that the precipitate produced had a burr-like appearance ( Figure 2 c), chemical composition is hydroxy iron sulfate mineral ( Figure 2 middle d);

[0111] Solid-liquid separation: The water sample obtained after the biomineralization treatment is allowed to settle, and lime is added to the supernatant to adjust the pH to 9.0. The heavy metal concentration in the effluent obtained meets the requirements for meeting the discharge standards.

[0112] Comparative Example 2

[0113] This comparative example provides the use of acidophilic algae-Parachlorella sp. AH02 in biological mineralization and iron removal of acid mine wastewater, that is, acidithiobacillus ferrooxidans LX5 is not added.

[0114] With reference to Example 1,

[0115] The water sample is the acid mine wastewater in Example 1, and the specific steps are as follows:

[0116] Inoculation: Add algae to the water sample at a density of 1×10 7 cells / mL of Parachlorella sp. AH02;

[0117] Add nutrients: 0.5g / L NaNO3;

[0118] Biomineralization treatment: 1.5mW / cm 2 The electron accepting capacity and electron donating capacity detected during the whole treatment process were 0.9 mmol e - / g C and 0.7mmol e - / g C; but no hydroxyl radicals were produced; the pH value of the treated water sample was 2.7, and the Fe(II) content was 612 mg / L ( Figure 2 a), and no obvious precipitation was observed ( Figure 2 b);

[0119] Solid-liquid separation: The water sample after biomineralization treatment is allowed to settle, and lime is added to the supernatant to adjust the pH to 12.0. The heavy metal concentration in the effluent meets the requirements for standard discharge.

[0120] Comparative Example 3

[0121] This comparative example provides a method and application thereof for accelerating iron biomineralization in acid mine wastewater by algae-bacteria symbiosis of acidophilic ferrooxidans and acidophilic algae that are not synchronously inoculated.

[0122] Referring to Example 1, the difference is that Acidithiobacillus ferrooxidans LX5 and Parachlorella sp. AH02 are not inoculated synchronously, and the specific steps are as follows:

[0123] Inoculation: Add bacteria at a density of 5×10 7 Acidithiobacillus ferrooxidansLX5 per mL;

[0124] Add nutrients: 0.5g / L NaNO3;

[0125] Biomineralization treatment: 1.5mW / cm 2 The treatment was carried out for 4 h under the conditions of light and 18 °C, and then the algae density was 1×10 7 cells / mL of Parachlorella sp. AH02, and then continued to culture under the same conditions for 4 h. The electron accepting capacity and electron supplying capacity of the system were tested to be 0.3 mmol e - / g C and 0.2mmol e - / g C; the cumulative concentration of hydroxyl radicals was about 10μM; the treated water sample was analyzed, the pH value of the solution was 2.5, the Fe(II) content was reduced to 115mg / L, and a certain amount of reddish-brown precipitate was produced; XRD detection showed that the produced precipitate was hydroxyferric sulfate mineral.

[0126] Solid-liquid separation: The water sample after biomineralization treatment is allowed to settle, and lime is added to the supernatant to adjust the pH to 9.0. The heavy metal concentration in the effluent meets the requirements for standard discharge.

Claims

1. An algae-bacteria symbiotic system, characterized in that: The algae-bacteria symbiotic system comprises acidothiobacillus ferrooxidans and acidothiobacillus.

2. The algae-bacteria symbiotic system according to claim 1, characterized in that: The Acidithiobacillus ferrooxidans LX5 is deposited in the General Microbiological Center of China National Committee for the Administration of Microbiological Culture Collection on March 13, 2002, with a deposit number of CGMCCNO.0727; and / or The acidophilic algae is Parachlorella sp. AH02, which is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration. The deposit date is June 5, 2023, and the deposit number is CGMCC NO.40698.

3. Use of the algae-bacteria symbiotic system according to claim 1 or 2 in accelerating the biological mineralization of iron in acidic mine wastewater.

4. The use according to claim 3, characterized in that: The applications include: S1, Acidithiobacillus ferrooxidans and Acidophilus algae were inoculated into acid mine drainage simultaneously; S2, adding nutrients; S3, subjecting acid mine drainage to light conditions for iron biomineralization.

5. A method for accelerating iron biomineralization in acid mine drainage, characterized in that: The method is to form an algae-bacteria symbiotic system in acidic mine wastewater, and specifically comprises the following steps: M1, Acidithiobacillus ferrooxidans and Acidophilus algae were inoculated into acid mine drainage simultaneously; M2, added nutrients; M3, subjecting acid mine drainage to light conditions for iron biomineralization.

6. Use of the algae-bacteria symbiotic system according to claim 1 or 2, or the method for accelerating iron biomineralization in acid mine drainage according to claim 5, in treating acid mine drainage.

7. A process for treating acid mine wastewater, characterized in that: The process comprises: N1, Acidithiobacillus ferrooxidans and Acidophilus algae were inoculated into acid mine drainage simultaneously; N2, adding nutrients; N3, placing the acid mine drainage water under light conditions for iron biomineralization, and obtaining treated wastewater after static sedimentation; N4, add alkaline substances to the treated wastewater to adjust the pH and obtain the final effluent.

8. A process for treating acid mine drainage according to claim 7, characterized in that: The inoculation density of the Acidithiobacillus ferrooxidans was 1×10 7 ~1×10 9 / mL; the inoculation density of the acidophilic algae is 1×10 6 ~1×10 8 Pieces / mL.

9. A process for treating acid mine drainage according to claim 7 or 8, characterized in that: The nutrient agent includes (g / L): any one or more of NaNO3 0.1-1.5, K2HPO4 0.01-0.04, MgSO4·7H2O 0.01-0.075, CaCl2·2H2O0.01-0.036, NaCO3 0.01-0.02, propionic acid 0.01-0.2, and citric acid 0.001-0.

01.

10. A process for treating acid mine drainage according to claim 9, characterized in that: The illumination conditions include: illumination intensity 0.2-2 mW / cm 2 ; The iron biogenic mineralization conditions include: 6 to 8 hours at 15 to 35°C.

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