Biological agent for removing arsenic and antimony as well as preparation method and application of biological agent

Abstract

The invention provides a biological agent for removing arsenic and antimony and a preparation method and application thereof, and belongs to the technical field of wastewater treatment.The preparation method of the biological agent for removing arsenic and antimony comprises the steps that porous calcium alginate microspheres and a biological agent solution are mixed, stirred, filtered and dried, and the biological agent for removing arsenic and antimony is obtained; the biological agent solution is prepared by mixing a mixed bacterium solution of iron bacteria and thiobacillus and an iron salt solution, the arsenic and antimony removal biological agent is good and stable in treatment effect, and the treatment efficiency of arsenic and antimony in wastewater reaches 99% or above; the method is simple in process, convenient to operate, low in operation cost, good in economic benefit and free of secondary pollution to the environment.

Description

Technical Field

[0001] The invention belongs to the technical field of wastewater treatment, and in particular relates to a biological preparation for removing arsenic and antimony, and a preparation method and application thereof. Background Art

[0002] Against the background of capacity integration in China, a large number of antimony mining and dressing companies, antimony smelting companies and antimony mines have been closed down. These historical legacy companies have discharged large amounts of arsenic and antimony pollutants into the environment in various forms, causing serious arsenic and antimony pollution in groundwater and surface water in the mining area and nearby areas. The polluted water enters the soil or river sediment through multiple pathways such as adsorption, precipitation, and biological absorption, and is then transferred to the human body through the food chain, posing a serious threat to the life and health of local residents and the safety of agricultural products.

[0003] At present, the most commonly used methods for heavy metal wastewater treatment are neutralization precipitation, coagulation precipitation and adsorption. Neutralization precipitation is to adjust the pH value of wastewater so that the heavy metal ions in the wastewater are - or S 2- A precipitate that is insoluble in water is formed, and then the heavy metal ions in the wastewater are finally removed through solid-liquid separation. This method can quickly remove heavy metal ions in wastewater, with a simple process and easy operation. However, due to the characteristics of heavy metal wastewater such as complex composition, high concentration, many types, and large amount of water, the traditional chemical precipitation method cannot achieve simultaneous deep purification of multiple metals in wastewater. Under normal circumstances, the heavy metal ions in the treated effluent are difficult to stabilize, difficult to meet national emission standards, and easy to cause secondary pollution to the environment. Coagulation precipitation and adsorption methods have a good treatment effect on heavy metal ions such as cadmium, arsenic, lead, and zinc, but it is difficult to remove ions such as antimony that are seriously harmful. This process consumes a large amount of flocculants, activated carbon and other agents. If the pH value is not adjusted, it will be difficult to remove pollutants in the water, and the activated carbon will be difficult to recover.

[0004] Due to the limitations of traditional treatment methods and reagent functions, the operating results are not ideal, the treatment cost is high, and it is easy to cause secondary pollution when treating arsenic and antimony-containing wastewater. Therefore, there is an urgent need to find a new functional material that is efficient, energy-saving and environmentally friendly for treating such wastewater or groundwater of similar nature. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a biological preparation for arsenic and antimony removal, and its preparation method and application. The biological preparation for arsenic and antimony removal of the present invention has good and stable treatment effect, and the treatment efficiency of arsenic and antimony in wastewater reaches more than 99%.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a method for preparing a biological agent for removing arsenic and antimony, comprising the following steps:

[0008] The porous calcium alginate microspheres are mixed with the biological agent solution, stirred, filtered and dried to obtain the arsenic and antimony removal biological agent;

[0009] The biological agent solution is prepared by mixing a mixed bacterial solution of iron bacteria and thiobacillus with an iron salt solution, and is used for microorganisms to be immersed and implanted in porous calcium alginate microspheres.

[0010] Preferably, the preparation method of the porous calcium alginate microspheres is:

[0011] Sodium alginate and polyvinyl alcohol are stirred and dissolved, and added dropwise into a borax solution. Then the sodium salt microspheres are taken out and placed into a calcium chloride aqueous solution to form porous microspheres. Porous calcium alginate microspheres can be obtained by heating.

[0012] Preferably, the volume ratio of the sodium alginate solution, the polyvinyl alcohol solution and the borax solution is 1:1:1;

[0013] The concentration of the sodium alginate solution is 5%, the concentration of the polyvinyl alcohol solution is 2%, and the concentration of the borax solution is 2%-3%.

[0014] Preferably, the calcium chloride concentration is 4% to 5%; the heating temperature is 70 to 100° C., and the heating time is 10 to 20 minutes.

[0015] Preferably, the mixing and stirring is carried out at a temperature of 20 to 40° C., for a time of 24 to 72 hours, and at a stirring speed of 20 to 30 r / min.

[0016] Preferably, the drying temperature is 100-200° C. and the drying time is 12-24 hours.

[0017] Preferably, the volume mass ratio of the mixed bacterial liquid to the iron salt is 100 ml: 20-80 g.

[0018] More preferably, the bacterial content of the mixed bacterial solution is 3×10 8 CFU / mL, the ratio of iron bacteria and thiobacillus in the mixed bacterial solution was 2:1;

[0019] The iron salt solution is an aqueous solution containing one or more of ferric sulfate, ferrous sulfate, ferric chloride, ferrous chloride, ferric nitrate, ferrous nitrate, polyferric sulfate and polyferric chloride; the concentration of the iron salt solution is 20-150 g / L.

[0020] More preferably, the method for preparing the mixed bacterial solution of iron bacteria and thiobacillus is:

[0021] The iron bacteria and thiobacillus were added into TSB medium at an inoculum of 5% and cultured for 3 days at a temperature of 20 to 40°C and a pH value of 2.0 to 3.5;

[0022] The TSB culture medium consists of 30 g / L peptone, 5 g / L yeast extract and 10% glucose.

[0023] In a second aspect, the present invention provides a biological agent for removing arsenic and antimony, which is prepared by the above-mentioned preparation method.

[0024] In a third aspect, the present invention provides the use of the above-mentioned biological agent for removing arsenic and antimony in purifying arsenic-antimony-containing mine wastewater, wherein the purification method includes adjustment, precipitation, biological fluidized reaction, and deep bed ion reaction;

[0025] The addition and mixing of the arsenic and antimony removal biological preparations is controlled by aeration or mechanical stirring.

[0026] Preferably, the dosage of the biological agent for removing arsenic and antimony in the wastewater is 0.5-2.0 kg / m 3 ;

[0027] Preferably, the reaction time required for the biological agent for removing arsenic and antimony is 1 h to 3 h, the reaction temperature is 20 to 40° C., and the pH is 6 to 9.

[0028] Preferably, the reaction time is controlled to be less than 3 h under the condition that the total antimony concentration of the influent is not higher than 10 mg / L and the total arsenic concentration is not higher than 15 mg / L. 3 / d~3m 3 After 100 days of operation at a treatment capacity of / d, the total antimony concentration in the effluent was below 0.005mg / L, and the total arsenic concentration in the effluent was below 0.05mg / L.

[0029] Contains at least the following beneficial technical effects:

[0030] The porous calcium alginate microspheres and the biological agent solution are mixed and stirred, and then filtered and dried to obtain the arsenic and antimony removal biological agent; the arsenic and antimony removal biological agent of the present invention has good and stable treatment effect, and the treatment efficiency of arsenic and antimony in wastewater reaches more than 99%; the process is simple, the operation is convenient, the operating cost is low, the economic benefit is good, and there is no secondary pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the process flow of using biological agents for arsenic and antimony removal. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0033] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0034] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the main idea or essential features of the present invention. Therefore, from all points of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the claims involved.

[0035] In addition, it should be understood that although this specification is described according to the implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. These other implementation modes are also covered within the protection scope of the present invention.

[0036] It should also be understood that the specific embodiments described above are only used to explain the present invention, and the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, which should be covered by the protection scope of the present invention / invention.

[0037] The mixed bacterial solution prepared in the following examples is as follows: iron bacteria and thiobacillus are placed in a 2L container of TSB medium (30 g / L peptone, 5 g / L yeast extract, 10% glucose) at an inoculum volume of 5%, the temperature is controlled at 20°C, the pH value is 2.0, and the culture is carried out for 3 days, wherein the iron bacteria are 2×10 8 CFU / mL, Thiobacillus is 1×10 8 CFU / mL.

[0038] Example 1

[0039] This embodiment provides a method for preparing a biological agent for removing arsenic and antimony:

[0040] S1. Dissolve 400g of ferrous sulfate and 278g of ferrous sulfate in 10L of water, mix with 1L of mixed bacterial solution at 100r / min, control the temperature at 35°C, stir and react for 2h to obtain a biological agent solution with a mass volume concentration of 152g / L.

[0041] S2. Stir and mix 5% sodium alginate and 2% polyvinyl alcohol evenly, add 2% borax dropwise, take out the sodium salt microspheres and put them into 4% calcium chloride aqueous solution, control the heating temperature to 70°C and the heating time to 10 min, and obtain porous calcium alginate microspheres; wherein the volume ratio of sodium alginate solution, polyvinyl alcohol solution and borax solution is 1:1:1.

[0042] S3. Place the porous calcium alginate microspheres obtained in S2 into the biological agent solution prepared in S1, control the temperature at 20°C, soak and stir for 24 hours, and stir at a speed of 20r / min. Filter through a filter, and dry the solid at 200°C for 12 hours to obtain an arsenic and antimony removal biological agent with a particle size of 2mm.

[0043] Example 2

[0044] This embodiment provides a method for preparing a biological agent for removing arsenic and antimony:

[0045] S1. Dissolve 180g of ferric chloride and 132g of ferrous chloride in 10L of water, mix with 1L of mixed bacterial solution at 100r / min, control the temperature at 35°C, stir and react for 2h to obtain a biological agent solution with a mass volume concentration of 113g / L.

[0046] S2. Stir and mix 5% sodium alginate and 2% polyvinyl alcohol, add 3% borax dropwise, take out the sodium salt microspheres and put them into 5% calcium chloride aqueous solution, control the heating temperature to 85°C and the heating time to 15 minutes, and obtain porous calcium alginate microspheres.

[0047] S3. Place the porous calcium alginate microspheres obtained in S2 into the biological agent solution prepared in S1, control the temperature at 30°C, soak and stir for 48 hours, stir at a speed of 30r / min, filter through a filter, and dry the solid at 160°C for 15 hours to obtain an arsenic and antimony removal biological agent with a particle size of 2mm.

[0048] Example 3

[0049] This embodiment provides a method for preparing a biological agent for removing arsenic and antimony:

[0050] S1. Dissolve 328g of ferric nitrate and 240g of ferrous nitrate in 10L of water, mix with 1L of mixed bacterial solution at 100r / min, control the temperature at 35°C, stir and react for 2h to obtain a biological agent solution with a mass volume concentration of 134g / L.

[0051] S2. Stir and mix 5% sodium alginate and 2% polyvinyl alcohol evenly, add 2% borax dropwise, take out the sodium salt microspheres and put them into 4% calcium chloride aqueous solution, control the heating temperature to 100°C and the heating time to 20 min, and obtain porous calcium alginate microspheres, wherein the volume ratio of sodium alginate solution, polyvinyl alcohol solution and borax solution is 1:1:1.

[0052] S3. Place the porous calcium alginate microspheres obtained in S2 into the biological agent solution prepared in S1, control the temperature at 40°C, soak and stir for 72 hours, and stir at a speed of 30 r / min. Filter through a filter, and dry the solid at 100°C for 24 hours to obtain an arsenic and antimony removal biological agent with a particle size of 2 mm.

[0053] Example 4

[0054] This embodiment provides a method for preparing a biological agent for removing arsenic and antimony:

[0055] S1. Dissolve 185g of ferric nitrate and 160g of ferric sulfate, and 108g of ferrous chloride in 10L of water, mix with 1L of mixed bacterial solution at 100r / min, control the temperature at 35°C, stir and react for 2h, and obtain a biological agent solution with a mass volume concentration of 126g / L.

[0056] S2. Stir and mix 5% sodium alginate and 2% polyvinyl alcohol evenly, add 2% borax dropwise, take out the sodium salt microspheres and put them into 5% calcium chloride aqueous solution, control the heating temperature to 90°C and the heating time to 15 min, and obtain porous calcium alginate microspheres, wherein the volume ratio of sodium alginate solution, polyvinyl alcohol solution and borax solution is 1:1:1.

[0057] S3. Place the porous calcium alginate microspheres obtained in S2 into the biological agent solution prepared in S1, control the temperature at 30°C, soak and stir for 48 hours, stir at 24r / min, filter through a filter, and dry the solid at 80°C for 16 hours to obtain an arsenic and antimony removal biological agent with a particle size of 2mm.

[0058] Example 5

[0059] This embodiment provides a method for preparing a biological agent for removing arsenic and antimony:

[0060] S1. Dissolve 212g of ferric chloride, 148g of ferrous sulfate, and 185g of ferric nitrate in 10L of water, mix with 1L of mixed bacterial solution at 100r / min, control the temperature at 35°C, stir and react for 2h to obtain a biological agent solution with a mass volume concentration of 136g / L.

[0061] S2. Stir and mix 5% sodium alginate and 2% polyvinyl alcohol evenly, add 3% borax dropwise, take out the sodium salt microspheres and put them into 4% calcium chloride aqueous solution, control the heating temperature to 80°C and the heating time to 15 min, and obtain porous calcium alginate microspheres, wherein the volume ratio of sodium alginate solution, polyvinyl alcohol solution and borax solution is 1:1:1.

[0062] S3. Place the porous calcium alginate microspheres obtained in S2 into the biological agent solution prepared in S1, control the temperature at 30°C, soak and stir for 36 hours, stir at a speed of 20 r / min, filter through a filter, and dry the solid at 90°C for 20 hours to obtain an arsenic and antimony removal biological agent with a particle size of 2 mm.

[0063] Experimental example

[0064] The arsenic and antimony removal biological preparations prepared in Examples 1-5 of the present invention were added to the biological fluidized bed reactor at a dosage of 2.0 kg / m 3 , the reaction time was controlled to be 2h, the reaction temperature to be 30℃, the pH to be 8, the total antimony in the influent to be 10mg / L, the total arsenic to be 15mg / L, the flow rate to be 2m 3 / d, the effluent effect was checked after 60 days of operation. The test results are shown in Table 1, which are in line with the national "Surface Water Environmental Quality Standard" (GB 3838-2002) standard.

[0065] Table 1

[0066] Water testing items Example 1 Example 2 Example 3 Example 4 Example 5 Total antimony (μg / L) 4.28 4.56 3.81 3.63 4.06 Total arsenic (μg / L) 48.22 44.36 38.62 40.48 41.72

Claims

1. A method for preparing a biological agent for removing arsenic and antimony, characterized in that: The following steps are involved: The porous calcium alginate microspheres are mixed with the biological agent solution, stirred, filtered and dried to obtain the arsenic and antimony removal biological agent; The biological agent solution is prepared by mixing a mixed bacterial solution of iron bacteria and thiobacillus with an iron salt solution.

2. The preparation method according to claim 1, characterized in that: The preparation method of the porous calcium alginate microspheres is: Sodium alginate and polyvinyl alcohol are stirred and dissolved, and added dropwise into a borax solution. Then the sodium salt microspheres are taken out and placed into a calcium chloride aqueous solution to form porous microspheres. Porous calcium alginate microspheres can be obtained by heating.

3. The preparation method according to claim 2, characterized in that: The volume ratio of the sodium alginate solution, the polyvinyl alcohol solution and the borax solution is 1:1:1; The concentration of the sodium alginate solution is 5%, the concentration of the polyvinyl alcohol solution is 2%, and the concentration of the borax solution is 2%-3%.

4. The preparation method according to claim 2, characterized in that: The calcium chloride concentration is 4% to 5%; the heating temperature is 70 to 100° C., and the heating time is 10 to 20 minutes.

5. The preparation method according to claim 1, characterized in that: The mixing and stirring is performed at a temperature of 20 to 40° C., for a time of 24 to 72 hours, and at a stirring speed of 20 to 30 r / min.

6. The preparation method according to claim 1, characterized in that: The drying temperature is 100-200° C., and the drying time is 12-24 hours.

7. The preparation method according to claim 1, characterized in that: The volume mass ratio of the mixed bacterial liquid to the iron salt is 100ml:20-80g; The bacterial content of the mixed bacterial solution is 3×10 8 CFU / mL, the ratio of iron bacteria and thiobacillus in the mixed bacterial solution was 2:1; The iron salt solution is an aqueous solution containing one or more of ferric sulfate, ferrous sulfate, ferric chloride, ferrous chloride, ferric nitrate, ferrous nitrate, polyferric sulfate and polyferric chloride; the concentration of the iron salt solution is 20-150 g / L.

8. A biological agent for removing arsenic and antimony, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 7.

9. The use of the biological agent for removing arsenic and antimony according to claim 8 in purifying arsenic-antimony-containing mine wastewater, characterized in that: The purification methods include conditioning, precipitation, biofluidization reaction, and deep bed ion reaction; The addition and mixing of the arsenic and antimony removal biological preparations is controlled by aeration or mechanical stirring.

10. The use according to claim 8, characterized in that: The dosage of the biological agent for removing arsenic and antimony in the wastewater is 0.5-2.0 kg / m 3 ; The reaction time required for the biological preparation for removing arsenic and antimony is 1 h to 3 h, the reaction temperature is 20 to 40° C., and the pH is 6 to 9.

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