Method for preparing waste incineration flue gas demercuration adsorbent by utilizing microorganism induced corrosion waste battery slag

Abstract

The invention discloses a method for preparing a waste incineration flue gas demercuration adsorbent by utilizing microorganism induced corrosion waste battery slag, which comprises the following steps: firstly, preparing an SRB (sulfate reducing bacteria) seed culture medium by mixing SRB and an anaerobic culture medium, and then adding sulfur-rich waste battery slag into the SRB seed culture medium for anaerobic reaction; and after the reaction is finished, centrifuging, washing with deionized water and drying to obtain amorphous iron sulfide (FeSx) generated by microorganism induced corrosion. According to the method, the sulfate reducing bacteria culture medium is used as the precursor solution, the waste battery slag is subjected to anaerobic modification to prepare the mercury removal adsorbent, on one hand, high-valued and resource utilization of the sulfur-rich waste battery slag is achieved, and on the other hand, the method capable of rapidly, accurately and simply preparing the high-activity amorphous metal sulfide adsorbent in a large-scale mode is explored. Meanwhile, the type of the flue gas demercuration adsorbent is also expanded.

Description

Technical Field

[0001] The invention relates to the technical field of adsorbent preparation, in particular to a method for preparing a waste incineration flue gas mercury removal adsorbent by utilizing microorganism-induced corrosion of waste battery residue. Background Art

[0002] Mercury is a heavy metal pollutant with strong biological toxicity, high volatility and long-lasting enrichment. With the surge in waste treatment and the application of incineration technology, flue gas mercury emissions have become the main source of anthropogenic mercury pollution. In waste incineration flue gas, the typical forms of mercury can be divided into elemental mercury (Hg 0 ), oxidized mercury (Hg 2+ ) and particulate mercury (Hgp). 0 Due to its closed outer electron structure, it is insoluble in water and has stable chemical properties. It is more volatile and is the focus of removing pollutants from incineration flue gas.

[0003] Adsorption, the most established technology for flue gas mercury removal, has been widely studied for its ease of use and low energy consumption. Its core technology lies in the optimal selection of adsorbents, but traditional adsorption materials such as activated carbon suffer from high cost and insufficient kinetic performance. Transition metal sulfides possess abundant sulfur sites on their surfaces, which react with HgO to form stable mercury sulfide (HgS), preventing the secondary release of mercury that could further pollute the environment and present promising application prospects.

[0004] It's worth noting that the rapid expansion of my country's new energy industry has generated a significant amount of lithium-ion battery acid-etched waste residue. This waste battery residue (WBS) is rich in sulfates, such as iron sulfate (FeSO4) and calcium sulfate (CaSO4). Traditional landfilling or high-temperature melting of this waste residue can cause secondary pollution and consume significant energy. A green conversion process can transform this waste into a mercury removal adsorbent, effectively repurposing it as a solid waste resource and providing a novel material for flue gas mercury treatment, creating a "waste-to-pollution" cycle.

[0005] Microbially induced corrosion (MICC) is a natural phenomenon that occurs widely across various environments and industrial sectors. During this process, the metabolic activities of microorganisms such as sulfate-reducing bacteria, sulfur-oxidizing bacteria, saprophytes, iron bacteria, and fungi induce localized corrosion and dissolution of metals and minerals under appropriate conditions. Among these, commonly used sulfate-reducing bacteria (SRB) can use sulfate ions as electron acceptors and enzymatically reduce sulfate to sulfide. This reaction significantly reduces the activation energy, allowing the reaction to proceed efficiently at room temperature and atmospheric pressure, making it a research hotspot in the materials field. Summary of the Invention

[0006] The present invention aims to address the problems existing in the background technology and propose a method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery slag, thereby achieving effective utilization of solid waste resources and solving the problem of the cumbersome synthesis process of highly active amorphous metal sulfides.

[0007] The technical solution of the present invention is a method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery residue, characterized in that it comprises the following steps:

[0008] SRB seed culture medium is prepared by mixing SRB and sterile anaerobic culture medium and curing them;

[0009] Sulfur-rich WBS was added to the SRB seed culture medium to conduct anaerobic corrosion reaction;

[0010] After the reaction is completed, the amorphous iron sulfide adsorbent FeSx produced by microbial-induced corrosion is obtained through centrifugation, deionized water washing and drying steps, where x is 0.5-2.

[0011] Furthermore, the SRB was isolated from a soil sample collected from Jiangsu Province, China, and the SRB isolate was confirmed to belong to Desulfovibrio vulgaris by BLAST analysis.

[0012] Furthermore, the WBS is lithium battery waste residue, wherein the amorphous metal sulfide in the lithium battery waste residue participates in the reaction.

[0013] Furthermore, the sterile anaerobic culture medium is configured according to the following components:

[0014] 0.5 parts K2HPO4, 1 part NH4Cl, 20 parts MgSO4·7H2O, 1 part Na2SO4, 1 part cysteine, 0.1 part vitamin C, and 2 parts sodium lactate;

[0015] The prepared culture medium was sterilized, and the pH value of the prepared culture medium was 7.2.

[0016] Furthermore, the prepared anaerobic culture medium is sterilized at a temperature of 80 to 150° C. for 10 to 30 minutes, preferably at 121° C. for 20 minutes.

[0017] Furthermore, when preparing the SRB seed culture medium, the mixing ratio of SRB and sterile anaerobic culture medium is 1:20 to 1:5; preferably 1:9.

[0018] Furthermore, the SRB and the sterile anaerobic culture medium are mixed by static stirring at room temperature or by magnetic stirring at room temperature for 5 to 30 minutes, preferably by magnetic stirring at room temperature for 10 minutes.

[0019] Further, when preparing the SRB seed culture, the curing temperature is 25-45 DEG C, and the curing time is 2-5 days.

[0020] Further, the anaerobic corrosion reaction is carried out in an anaerobic glove box, and 10g of WBS and 100ml of SRB seed culture are sequentially added to the glass bottle and sealed.

[0021] Further, the anaerobic corrosion reaction temperature is 15-45 DEG C, and the reaction time is 3 days, 7 days, 14 days, 21 days and 42 days; preferably, the reaction temperature is 37 DEG C, and the reaction time is 21 days.

[0022] The centrifugation and deionized water washing after the anaerobic corrosion reaction are repeated for 3-10 times; preferably, 4-6 times.

[0023] The temperature of the drying step is selected as 80 DEG C, and the drying time is 12h.

[0024] A flue gas mercury removal adsorbent is prepared by the method, and the prepared flue gas mercury removal adsorbent is applied to the mercury removal of waste incineration flue gas and other various incineration flue gas.

[0025] Compared with the prior art, the present application has the following beneficial technical effects:

[0026] (1) Compared with the traditional disposal method of waste battery slag, the present application realizes high-value resource conversion of waste battery slag, and the material preparation process is simple, the reaction conditions are relatively mild, and the energy consumption is low.

[0027] (2) Compared with the existing mercury removal adsorbent, the present application uses sulfur-rich waste as raw material to obtain an adsorbent with excellent mercury removal performance at a low cost, and is widely applicable to the mercury removal of waste incineration flue gas and other various incineration flue gas. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The process flow chart for preparing the adsorbent is shown in the figure;

[0029] Figure 2 The crystal structure diagram of the adsorbent obtained from the original waste battery slag and the implementation cases 2-4 of the present application is shown in the figure;

[0030] Figure 3 The surface energy spectrum diagram of the adsorbent obtained from the original waste battery slag, the implementation case 2 and the implementation case 4 of the present application is shown in the figure;

[0031] Figure 4 The Hg adsorption efficiency diagram of the adsorbent obtained from the original waste battery slag and the implementation cases 1-5 of the present application is shown in the figure;

[0032] Figure 5 Figure 1 is a graph of Hg adsorption capacity of the adsorbent obtained from the raw spent battery slag and the cases 1-5 of the present application. DETAILED DESCRIPTION

[0033] The present application will be further described in detail with reference to the following embodiments and accompanying drawings. However, the present application is not limited to the following embodiments. The original WBS was subjected to experiments under the conditions of simulated flue gas, and the experimental conditions were as follows: initial mercury concentration 100 μg / m3; flue gas flow rate 1 L / min; simulated flue gas components N2+Hg 0 ; reaction temperature 120°C; after the reaction, the concentration before and after the reaction was detected by an on-line mercury concentration detector, and the mercury removal efficiency was calculated, and the mercury removal efficiency at the 90th minute was 2.56%.

[0034] Example 1

[0035] The SRB was isolated from a soil sample collected in Jiangsu Province, China. The medium was prepared according to the components shown in Table 1, and then the medium was sterilized at 121°C for 20 minutes.

[0036] Table 1 Medium component table

[0037]

[0038] Then 50 ml of the SRB was mixed with 450 ml of the sterile medium in a 1000 ml beaker, and the mixture was reacted under the condition of magnetic stirring at room temperature for 10 minutes, and then incubated at 37°C for 3 days to obtain the sterile SRB medium. In an anaerobic glove box, 10 grams of the WBS was weighed and transferred to a 100 ml glass bottle with a sealable airtight cap. Then, 100 ml of the SRB medium was weighed and poured into the glass bottle to mix with the WBS, ensuring that the residual air was completely discharged and sealed. Then the system was placed in a temperature-controlled incubator for microbial corrosion reaction at 37°C, and the reaction time was 3 days. After the reaction, the generated suspension was filtered and the solid residue was separated, washed with deionized water for 3 times, and then dried at 80°C for 12 hours to obtain the sample BS-M-3D. The simulated flue gas experiment was carried out under the same conditions as above, and after the reaction, the concentration before and after the reaction was detected by an on-line mercury concentration detector, and the mercury removal efficiency was calculated, and the mercury removal efficiency at the 90th minute was 14.37%; the mercury removal adsorbent after the reaction can be recovered and reused by heat regeneration, solvent regeneration and the like.

[0039] Example 2

[0040] SRB were isolated from soil samples collected in Jiangsu Province, China. A culture medium was prepared according to the components listed in Table 1 and sterilized at 121°C for 20 minutes. Subsequently, 50 ml of SRB and 450 ml of sterile culture medium were poured into a 1000 ml beaker and mixed. The mixture was reacted at room temperature with magnetic stirring for 10 minutes and then cured at 37°C for 3 days to obtain a sterile SRB culture medium. In an anaerobic glove box, 10 g of WBS was weighed and transferred to a 100 ml glass bottle fitted with a sealable airtight lid. Subsequently, 100 ml of SRB culture medium was weighed and poured into the glass bottle to mix with the WBS, ensuring that any trapped air was completely expelled and sealed. The system was then placed in a temperature-controlled incubator and subjected to microbial corrosion reaction at 37°C for 7 days. After the reaction, the resulting suspension was filtered, and the solid residue was separated, washed three times with deionized water, and dried at 80°C for 12 hours to obtain sample BS-M-7D. A simulated flue gas experiment was conducted under the same conditions as above. After the reaction, the mercury concentration before and after the reaction was measured using an online mercury concentration detector to calculate the mercury removal efficiency. The mercury removal efficiency at the 90th minute was 39.34%. The mercury removal adsorbent after the reaction can be recovered and reused through thermal regeneration, solvent regeneration, etc.

[0041] Example 3

[0042] SRB were isolated from soil samples collected in Jiangsu Province, China. A culture medium was prepared according to the components listed in Table 1 and sterilized at 121°C for 20 minutes. Subsequently, 50 ml of SRB and 450 ml of sterile culture medium were poured into a 1000 ml beaker and mixed. The mixture was allowed to react at room temperature with magnetic stirring for 10 minutes, followed by curing at 37°C for 3 days to obtain a sterile SRB culture medium. In an anaerobic glove box, 10 g of WBS was weighed and transferred to a 100 ml glass bottle fitted with a sealable airtight lid. Subsequently, 100 ml of SRB culture medium was weighed and poured into the glass bottle to mix with the WBS, ensuring that any trapped air was completely expelled and sealed. The system was then placed in a temperature-controlled incubator and subjected to microbial corrosion reaction at 37°C for 14 days. After the reaction, the resulting suspension was filtered, and the solid residue was separated, washed three times with deionized water, and dried at 80°C for 12 hours to obtain sample BS-M-14D. A simulated flue gas experiment was conducted under the same conditions as above. After the reaction, the mercury concentration before and after the reaction was measured using an online mercury concentration detector to calculate the mercury removal efficiency. The mercury removal efficiency at the 90th minute was 73.36%. The mercury removal adsorbent after the reaction can be recovered and reused through thermal regeneration, solvent regeneration, etc.

[0043] Example 4

[0044] SRB were isolated from soil samples collected in Jiangsu Province, China. A culture medium was prepared according to the components listed in Table 1 and sterilized at 121°C for 20 minutes. Subsequently, 50 ml of SRB and 450 ml of sterile culture medium were poured into a 1000 ml beaker and mixed. The mixture was allowed to react at room temperature with magnetic stirring for 10 minutes, followed by curing at 37°C for 3 days to obtain a sterile SRB culture medium. In an anaerobic glove box, 10 g of WBS was weighed and transferred to a 100 ml glass bottle fitted with a sealable airtight lid. Subsequently, 100 ml of SRB culture medium was weighed and poured into the glass bottle to mix with the WBS, ensuring that any trapped air was completely expelled and sealed. The system was then placed in a temperature-controlled incubator and subjected to microbial corrosion reaction at 37°C for 21 days. After the reaction, the resulting suspension was filtered, and the solid residue was separated, washed three times with deionized water, and dried at 80°C for 12 hours to obtain sample BS-M-21D. A simulated flue gas experiment was conducted under the same conditions as above. After the reaction, the mercury concentration before and after the reaction was measured using an online mercury concentration detector to calculate the mercury removal efficiency. The mercury removal efficiency at the 90th minute was 91.82%. The mercury removal adsorbent after the reaction can be recovered and reused through thermal regeneration, solvent regeneration, etc.

[0045] Example 5

[0046] SRB were isolated from soil samples collected in Jiangsu Province, China. A culture medium was prepared according to the components listed in Table 1 and sterilized at 121°C for 20 minutes. Subsequently, 50 ml of SRB and 450 ml of sterile culture medium were poured into a 1000 ml beaker and mixed. The mixture was allowed to react at room temperature with magnetic stirring for 10 minutes, followed by curing at 37°C for 3 days to obtain a sterile SRB culture medium. In an anaerobic glove box, 10 g of WBS was weighed and transferred to a 100 ml glass bottle fitted with a sealable airtight lid. Subsequently, 100 ml of SRB culture medium was weighed and poured into the glass bottle to mix with the WBS, ensuring that any trapped air was completely expelled and sealed. The system was then placed in a temperature-controlled incubator and subjected to microbial corrosion reaction at 37°C for 42 days. After the reaction, the resulting suspension was filtered, and the solid residue was separated, washed three times with deionized water, and dried at 80°C for 12 hours to obtain sample BS-M-42D. A simulated flue gas experiment was conducted under the same conditions as above. After the reaction, the mercury concentration before and after the reaction was measured using an online mercury concentration detector to calculate the mercury removal efficiency. The mercury removal efficiency at the 90th minute was 80.57%. The mercury removal adsorbent after the reaction can be recovered and reused through thermal regeneration, solvent regeneration, etc.

[0047] The present invention first prepares a sulfate-reducing bacteria (SRB) seed culture by mixing SRB with an anaerobic culture medium. Sulfur-rich waste battery residue is then added to the SRB seed culture medium for an anaerobic reaction. After the reaction is complete, amorphous iron sulfide (FeSx) produced by microbial-induced corrosion is obtained by centrifugation, washing with deionized water, and drying. Using the sulfate-reducing bacteria culture medium as a precursor, the present invention anaerobically modifies waste battery residue to produce a mercury removal adsorbent. This method not only maximizes the value and resource utilization of sulfur-rich waste battery residue, but also explores a method for rapidly, accurately, simply, and scalably preparing a highly active amorphous metal sulfide adsorbent, thereby expanding the range of flue gas mercury removal adsorbents.

[0048] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A method for preparing a mercury removal adsorbent for waste incineration flue gas by using microbial-induced corrosion of waste battery residue, characterized in that: The following steps are involved: SRB seed culture medium is prepared by mixing SRB and sterile anaerobic culture medium and curing them; Sulfur-rich WBS was added to the SRB seed culture medium to conduct anaerobic corrosion reaction; After the reaction, the amorphous iron sulfide adsorbent FeS produced by microbial induced corrosion was obtained through centrifugation, deionized water washing and drying steps. x .

2. The method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery residue according to claim 1, characterized in that: The WBS is lithium battery waste.

3. The method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery residue according to claim 1, characterized in that: The sterile anaerobic culture medium is configured according to the following components: 0.5 parts K2HPO4, 1 part NH4Cl, 20 parts MgSO4·7H2O, 1 part Na2SO4, 1 part cysteine, 0.1 part vitamin C, and 2 parts sodium lactate; The prepared culture medium is sterilized, and the pH value of the prepared culture medium is 7.

2.

4. The method for preparing a waste incineration flue gas mercury removal adsorbent by utilizing microbial-induced corrosion of waste battery residue according to claim 1 or 3, characterized in that: The configured anaerobic culture medium is sterilized at a temperature of 80 to 150° C. and a sterilization time of 10 to 30 minutes.

5. The method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery slag according to claim 1, characterized in that: When preparing the SRB seed culture medium, the mixing ratio of SRB and sterile anaerobic culture medium is 1:20 to 1:

5.

6. The method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery residue according to claim 1 or 5, characterized in that: The SRB and the sterile anaerobic culture medium are mixed by static stirring or magnetic stirring at room temperature for 5 to 30 minutes.

7. The method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery residue according to claim 1, characterized in that: When preparing SRB seed culture medium, the curing temperature is 25-45°C and the curing time is 2-5 days.

8. The method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery residue according to claim 1, characterized in that: The anaerobic corrosion reaction was carried out in an anaerobic glove box, and 10 g of WBS and 100 ml of SRB seed culture medium were added to a glass bottle in sequence and sealed.

9. The method for preparing a mercury removal adsorbent for waste incineration flue gas by utilizing microbial-induced corrosion of waste battery residue according to claim 1 or 8, characterized in that: The anaerobic corrosion reaction temperature is 25-37°C, and the reaction time is 3 days, 7 days, 14 days, 21 days, and 42 days; The centrifugation and deionized water washing after the anaerobic corrosion reaction are repeated 3 to 10 times; The temperature of the drying step was selected to be 80°C and the drying time was 12 h.

10. A flue gas mercury removal adsorbent prepared by the method according to any one of claims 1 to 9, characterized in that: The prepared flue gas mercury removal adsorbent is used to remove mercury from waste incineration flue gas.

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