Simulation device and method for manganese slag leachate leaching microorganism solidification crushing zone

Abstract

The invention relates to a simulation device and a simulation method for a manganese slag leachate leaching microorganism solidification crushing zone. The simulation device comprises a liquid supplementing unit and a leaching unit, the simulation method comprises the following steps: S1, preparing manganese slag leachate; s2, preparing a microorganism curing and crushing zone sample; s3, simulating manganese slag leachate leaching process control; s4, resistance control effect evaluation; according to the method, the prepared manganese slag leachate and the prepared microorganism curing and crushing zone sample are assembled on the simulated leaching device, conversion and accumulation of the manganese slag leachate in the microorganism curing and crushing zone are simulated, and after leaching for a certain period of time, the resistance and control effect of the microorganism curing and crushing zone on the manganese slag leachate is evaluated; the simulation device can provide a certain guiding effect for practical application of the microorganism solidification technology in the aspect of anti-permeability reinforcement of the leakage channel of the crushed zone of the manganese slag storage yard, and the simulation device is simple in structure, high in operability and suitable for simulation leaching tests of centimeter-level and meter-level microorganism solidification crushed zone samples.

Description

Technical Field

[0001] The present invention relates to the technical field of microbial geotechnics, and particularly to a device and method for simulating the leaching of microbial solidified fractured zones by manganese slag leachate. Background Art

[0002] In China, the output of manganese slag is large and the utilization rate is low, resulting in a large stockpile of manganese slag. The large stockpile of manganese slag is piled up in the manganese slag yard. Due to the imperfect anti-seepage measures in the manganese slag yard, the manganese slag leaks severely, causing significant ecological and environmental risks. The fractured zone is one of the complex geological conditions usually faced at the bottom of the manganese slag yard, which will lead to serious pollution leakage problems, causing significant pollution to the surrounding soil and water and posing a great threat to human health. Therefore, grouting and plugging of the leakage channels in the manganese slag yard has become an engineering problem that needs to be solved urgently. The microbial solidification technology is a new type of geotechnical reinforcement method developed recently. At present, there are patents using the microbial solidification technology to carry out anti-seepage reinforcement on the leakage channels in the fractured zones of manganese slag yards. For example, the patent number is 202311388765.2, and the patent name is a fractured zone grouting test device and its grouting method. The proposed grouting method can achieve grouting and plugging of the leakage channels in the fractured zones of manganese slag yards.

[0003] However, due to the extremely high content of heavy metal pollutants in electrolytic manganese slag, the successful application of microbial solidification technology in the anti-seepage reinforcement of fractured zones in manganese slag yards not only needs to meet the improvement in terms of permeability and mechanical properties, but also needs to meet the environmental pollution standards for heavy metal pollutants in electrolytic manganese slag.

[0004] Based on this, the present invention designs a simulation device and method for the leaching of microbial solidified fractured zones by manganese slag leachate to carry out research on the control of heavy metal pollutants in manganese slag leachate by microbial solidified fractured zones. Summary of the Invention

[0005] In view of the above situation, the present invention designs a simulation device and method for the leaching of microbial solidified fractured zones by manganese slag leachate to carry out research on the control of heavy metal pollutants in manganese slag leachate by microbial solidified fractured zones, which can provide certain guidance for the practical application of microbial solidification technology in the anti-seepage reinforcement of leakage channels in fractured zones of manganese slag yards.

[0006] A simulation device for the leaching of microbial solidified fractured zones by manganese slag leachate includes a bracket, and is characterized in that a liquid supplement unit is suspended at the top of the bracket, and a leaching unit is suspended in the middle of the bracket.

[0007] Further, the liquid replenishment unit includes a liquid replenishment bottle. A liquid replenishment port is provided at the upper end of the liquid replenishment bottle. A liquid replenishment pipe is connected to the top end of the liquid replenishment port. A first water stop clamp is provided at the end of the liquid replenishment pipe. A third hose is connected to the bottom of the liquid replenishment bottle. The liquid replenishment unit and the leaching unit are connected through the third hose. A flow rate controller is provided in the middle of the third hose.

[0008] Further, the leaching unit includes a liquid inlet bottle. An overflow port is provided near the top on the side of the liquid inlet bottle. The overflow port is connected to an overflow liquid collection measuring cylinder through an overflow pipe. A first hose is connected to the bottom of the liquid inlet bottle. A second water stop clamp is provided in the middle of the first hose. The end of the first hose is connected to a specimen mold, and the connection is located at the bottom of the specimen mold. A test bench is provided at the bottom of the specimen mold for raising the height. A second hose is connected to the specimen mold near the top on one side. The other end of the second hose is connected to an effluent collection measuring cylinder.

[0009] Further, the connection between the overflow liquid collection measuring cylinder and the overflow pipe, and the connection between the effluent collection measuring cylinder and the second hose are both sealed with a sealing film to prevent the concentration of heavy metal pollutants in the solution from changing due to solution evaporation.

[0010] Further, the liquid replenishment pipe, the overflow pipe, the first hose, the second hose, and the third hose are all PVC material hoses.

[0011] A simulation method for a manganese slag leachate leaching microbial solidification and fragmentation zone uses a simulation device for a manganese slag leachate leaching microbial solidification and fragmentation zone, which is characterized by including the following steps:

[0012] S1. Prepare manganese slag leachate;

[0013] S2. Prepare a microbial solidification and fragmentation zone specimen;

[0014] S3. Simulate the process control of manganese slag leachate leaching;

[0015] S4. Conduct a control effect evaluation.

[0016] The beneficial effects of the above technical solutions are as follows:

[0017] (1) By assembling the prepared manganese slag leachate and the microbial solidification and fragmentation zone specimen on the simulation leaching device, the present invention simulates the transformation and accumulation of manganese slag leachate in the microbial solidification and fragmentation zone. After leaching for a certain period of time, the control effect of the microbial solidification and fragmentation zone on manganese slag leachate is evaluated, which can provide certain guidance for the practical application of the microbial solidification technology in the anti-seepage reinforcement of the leakage channels in the fragmentation zone of the manganese slag yard;

[0018] (2) The simulation device in the present invention has a simple structure and strong operability. It can not only simulate the long-term transformation and accumulation of manganese slag leachate in the microbial solidified and fractured zone, but also measure the change in the permeability coefficient of the microbial solidified and fractured zone. The device is applicable to the simulated leaching test of microbial solidified and fractured zone specimens at the centimeter and meter levels. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the simulated leaching device in the present invention;

[0020] Figure 2 It is a flow chart of the simulated leaching method of the present invention;

[0021] Figure 3 It is the change in the permeability coefficient of the microbial solidified and fractured zone specimen in the embodiment of the present invention;

[0022] Figure 4 It is the change in the concentration of manganese ions in the effluent of the microbial solidified and fractured zone specimen in the embodiment of the present invention.

[0023] In the figure: 1. Liquid replenishing bottle, 2. Liquid replenishing port, 3. Liquid replenishing tube, 41. First stopcock, 42. Second stopcock, 5. Liquid inlet bottle, 6. Overflow port, 7. Overflow tube, 8. Overflow liquid collecting measuring cylinder, 9. Specimen mold, 10. Specimen, 11. Effluent collecting measuring cylinder, 121. First hose, 122. Second hose, 123. Third hose, 13. Flow rate controller, 14. Test bench. Detailed Embodiments

[0024] The technical solution of the present invention will be further described below in conjunction with the drawings and embodiments. The following specific embodiments are helpful for those skilled in the art to further understand the present invention, but do not limit the present invention in any form. Additionally, it should be noted that for the sake of description, only the parts related to the present invention are shown in the drawings rather than all of them.

[0025] Example 1, as Figure 1 shown, a simulation device for leaching a microbial solidified and fractured zone with manganese slag leachate includes a bracket. A liquid replenishing unit is suspended at the top of the bracket, and a leaching unit is suspended in the middle of the bracket; the liquid replenishing unit includes a liquid replenishing bottle 1. A liquid replenishing port 2 is opened at the upper end of the liquid replenishing bottle. The top of the liquid replenishing port 2 is connected to a liquid replenishing tube 3. A first stopcock 41 is arranged at the end of the liquid replenishing tube 3. The bottom of the liquid replenishing bottle 1 is communicated with a third hose 123. The liquid replenishing unit is communicated with the leaching unit through the third hose 123. A flow rate controller 13 is arranged in the middle of the third hose 123.

[0026] In this embodiment, the liquid supplement unit and the leaching unit are suspended by a bracket in a vertical height distribution. When supplementing the liquid, the first water stop clip 41 is opened, and liquid is added through the liquid supplement port 2. The leachate flows into the leaching unit through the third hose 123, and the flow rate controller 13 can control the inflow rate.

[0027] Embodiment 2, based on Embodiment 1, the leaching unit includes a liquid inlet bottle 5. An overflow port 6 is opened near the top on the side of the liquid inlet bottle 5. The overflow port 6 is connected to an overflow liquid collection measuring cylinder 8 through an overflow pipe 7. The bottom of the liquid inlet bottle 5 is connected to a first hose 121. A second water stop clip 42 is provided in the middle of the first hose 121. The end of the first hose 121 is connected to a specimen mold 9, and the connection is located at the bottom of the specimen mold 9. A test bench 14 is provided at the bottom of the specimen mold 9 to raise the height. A second hose 122 is connected near the top on one side of the specimen mold 9, and the other end of the second hose 122 is connected to an outflow liquid collection measuring cylinder 11.

[0028] In this embodiment, when supplementing the liquid, the second water stop clip 42 is closed. When the leachate overflows into the overflow liquid collection measuring cylinder 8 in the liquid inlet bottle 5, the liquid supplement is completed. At this time, the second water stop clip 42 can be opened to allow the leachate to flow into the specimen mold 9 through the first hose 121 to leach the specimen 10. After the specimen is filled with the leachate, it flows into the outflow liquid collection measuring cylinder 11 from the upper end of the specimen mold 9 through the second hose 122. Since it is necessary for the leachate to fully react with the specimen 10, the test bench 14 is used to raise the height of the specimen mold 9.

[0029] Embodiment 3, based on Embodiment 2, the connection between the overflow liquid collection measuring cylinder 8 and the overflow pipe 7, and the connection between the outflow liquid collection measuring cylinder 11 and the second hose 122 are both sealed with a sealing film. The liquid supplement pipe 3, the overflow pipe 7, the first hose 121, the second hose 122, and the third hose 123 are all made of PVC material hoses to prevent the concentration of heavy metal pollutants in the solution from changing due to solution evaporation.

[0030] Embodiment 4, as Figure 2 shown, based on Embodiment 3, a simulation method for the leaching microbial solidification and fragmentation zone of manganese slag leachate includes S1, the preparation of manganese slag leachate:

[0031] S1-1: Add about two drops of a mixed solution of concentrated sulfuric acid and concentrated nitric acid with a mass ratio of 2:1 to about 1 L of deionized water to make the pH of the mixed solution 3.20 ± 0.05;

[0032] S1-2: Add a sulfuric acid-nitric acid leaching solution with a liquid-solid ratio of 10:1 and electrolytic manganese slag to a centrifuge tube. The electrolytic manganese slag in this embodiment is taken from a certain abandoned manganese slag yard in Xincheng County, Laibin City, Guangxi Zhuang Autonomous Region. This embodiment is carried out in a centrifuge tube with a volume of 50 mL;

[0033] S1-3. After tightly covering the tube cap, fix the centrifuge tube on a turning shaker, adjust the rotation speed to 30 ± 2 r / min, and turn and oscillate at 23 ± 2 °C for 18 ± 2 h. After reaching the extraction time, let it stand for 16 h, filter through a 0.45 μm filter and collect the leachate, i.e., the manganese slag leachate.

[0034] In this example, through experimental analysis, the leaching concentration of manganese in the electrolytic manganese slag is 1547 mg / L, the acid-soluble state is 52.75%, and the environmental pollution risk is extremely high risk.

[0035] Example 5. On the basis of Example 4, a method for simulating the leaching of manganese slag leachate on a microbial solidified fracture zone includes S2. Preparation of the microbial solidified fracture zone specimen:

[0036] S2-1. Activate and expand the culture of Bacillus pasteurii, and prepare a bacterial solution;

[0037] S2-2. Prepare a cementing solution composed of a urea solution and a calcium chloride solution;

[0038] S2-3. Use the grouting reinforcement device in the grouting device of a grouting device for reinforcing a soft interlayer - bedrock complex based on MICP technology with the patent number 202320485168.0 and the patent name to inject the mixed solution of the bacterial solution and the cementing solution into the fracture zone specimen to grout and reinforce the fracture zone specimen. In this example, the original fracture zone sample is taken from a manganese slag yard to be built in Yidu City, Hubei Province;

[0039] S2-4. Place the specimen after grouting and reinforcement at 30 ± 2 °C for 6 d to obtain the microbial solidified fracture zone specimen. In this example, the specimen is a 50 mm × 100 mm cylindrical specimen.

[0040] In this example, the activation and expansion culture of Bacillus pasteurii, the preparation of the bacterial solution and the cementing solution, and the grouting method used for the microbial solidified fracture zone are all prior arts and will not be elaborated too much.

[0041] Example 6. On the basis of Example 4, a method for simulating the leaching of manganese slag leachate on a microbial solidified fracture zone includes S3. Process control for simulating the leaching of manganese slag leachate:

[0042] S3-1. Open the first stopcock 41, close the second stopcock 42, use a syringe to fill the manganese slag leachate in step S1 into the replenishing liquid bottle through the replenishing liquid tube 3. After the manganese slag leachate flows from the overflow port 6 into the overflow liquid collection measuring cylinder 8, close the first stopcock 41;

[0043] S3-2. Place the microbial solidified fracture zone specimen prepared in step S2, i.e., specimen 10, in the specimen mold 9 in the leaching unit;

[0044] S3-3. Open the second water stop clip 42 to fill the manganese slag leachate into the specimen, and let it flow into and out of the effluent collection measuring cylinder 11 from the upper end of the specimen mold 9;

[0045] S3-4. Use the flow rate controller 13 to control the inflow rate of the manganese slag leachate into the feed bottle 5 to ensure that the outflow rate of the effluent from the microbial solidification and fragmentation zone into the effluent collection measuring cylinder 11 is equal;

[0046] S3-5. Close the second water stop clip 42 at regular intervals, collect the liquid in the effluent collection measuring cylinder 11, store it in a 4°C refrigerator, read the liquid volume, and calculate the permeability coefficient of the specimen. In this embodiment, the effluent is taken every 12 hours.

[0047] Example 7. On the basis of Example 6, a simulation method for leaching the microbial solidification and fragmentation zone with manganese slag leachate includes S4. Conduct a control effect evaluation:

[0048] (1) Analyze the change in the permeability coefficient of the microbial solidification and fragmentation zone specimen after long-term leaching:

[0049] In this embodiment, the change in the permeability coefficient of the microbial solidification and fragmentation zone specimen within 888 hours is calculated, as shown in Figure 3 . Within 888 hours, the permeability coefficient of the microbial solidification and fragmentation zone specimen is basically unchanged, indicating that the internal structure of the microbial solidification and fragmentation zone specimen is relatively stable and is basically not affected by the long-term erosion of the electrolytic manganese slag leachate.

[0050] (2) Analyze the change in the concentration of heavy metal pollutants and environmental risks in the effluent:

[0051] In this embodiment, the change in the concentration of manganese ions in the effluent of the microbial solidification and fragmentation zone specimen within 888 hours is calculated, as shown in Figure 4 . After 360 hours of the leaching test, the manganese ions in the microbial solidification and fragmentation zone specimen gradually tend to be stable, about 663 mg / L, which is much lower than the manganese ion concentration in the electrolytic manganese slag leachate. And after 888 hours, the acid-soluble state of manganese in the effluent is only 7.99%, and the environmental pollution risk is low risk. This shows that the microbial solidification and fragmentation zone specimen has a certain control effect on the manganese in the electrolytic manganese slag leachate.

[0052] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Those of ordinary skill in the art should understand that it is not necessary and impossible to list all the implementation manners here. It should be noted that without departing from the concept of the present invention, several deformations or modifications can be made to the device. These all belong to the protection scope of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A simulation device for leaching microorganisms into a broken zone by manganese slag leachate, comprising a support, characterized in that: A fluid infusion unit is suspended on the top of the support, and a leaching unit is suspended in the middle of the support.

2. The simulation device for leaching microorganisms and solidifying the broken zone of manganese slag leachate according to claim 1 is characterized in that: The rehydration unit comprises a rehydration bottle (1), a rehydration port (2) is provided at the upper end of the rehydration bottle, a rehydration tube (3) is connected to the top of the rehydration port (2), a first water stop clamp (41) is provided at the end of the rehydration tube (3), a third hose (123) is connected to the bottom of the rehydration bottle (1), the rehydration unit is connected to the leaching unit via the third hose (123), and a flow rate controller (13) is provided in the middle of the third hose (123).

3. The simulation device for leaching microorganisms and solidifying the broken zone of manganese slag leachate according to claim 2 is characterized in that: The leaching unit comprises a liquid inlet bottle (5), a side of the liquid inlet bottle (5) is provided with an overflow port (6) near the top, the overflow port (6) is connected to an overflow liquid collecting cylinder (8) through an overflow pipe (7), the bottom of the liquid inlet bottle (5) is connected to a first hose (121), the middle of the first hose (121) is provided with a second water stop clamp (42), the end of the first hose (121) is connected to a sample mold (9), and the connection point is located at the bottom of the sample mold (9), a test bench (14) is provided at the bottom of the sample mold (9) for raising the height, one side of the sample mold (9) is connected to a second hose (122) near the top, and the other end of the second hose (122) is connected to an effluent collecting cylinder (11).

4. The simulation device for leaching microorganisms and solidifying the broken zone of manganese slag leachate according to claim 3 is characterized in that: The connection between the overflow liquid collecting cylinder (8) and the overflow pipe (7), and the connection between the effluent collecting cylinder (11) and the second hose (122) are all sealed by sealing films to prevent the concentration of heavy metal pollutants in the solution from changing due to evaporation of the solution.

5. The simulation device for leaching microorganisms and solidifying the broken zone of manganese slag leachate according to claim 3 is characterized in that: The liquid infusion tube (3), the overflow tube (7), the first hose (121), the second hose (122) and the third hose (123) are all made of PVC material.

6. A method for simulating the leaching of manganese slag leachate into microorganisms to solidify a broken zone, using the simulation device for simulating the leaching of manganese slag leachate into microorganisms to solidify a broken zone according to claim 1, characterized in that: The steps include: S1. Prepare manganese slag leachate; S2, preparing microbial solidified broken zone samples; S3, simulated manganese slag leachate leaching process control; S4. Evaluate the blocking effect.

7. The method for simulating the leaching of manganese slag leachate and microbial solidification of the broken zone according to claim 6, characterized in that: The S1 specifically includes the following steps: S1-1, adding about two drops of a mixture of concentrated sulfuric acid and concentrated nitric acid in a mass ratio of 2:1 into about 1 L of deionized water and making the pH of the solution 3.20±0.05, thereby preparing a sulfuric acid and nitric acid extract; S1-2, adding sulfuric acid and nitric acid extract and electrolytic manganese slag with a liquid-to-solid ratio of 10:1 into a centrifuge tube; S1-3. Fix the centrifuge tube on a flip shaker, cover the tube tightly, adjust the rotation speed to 30±2r / min, flip and oscillate at 23±2℃ for 18±2h. When the extraction time is reached, let it stand for 16h, filter and collect the leaching solution, i.e., the manganese slag leachate, using a 0.45μm filter.

8. The method for simulating the leaching of manganese slag leachate and microbial solidification of the broken zone according to claim 6, characterized in that: The S2 specifically includes the following steps: S2-1, activating and expanding the culture of Bacillus pasteurianus, and preparing a bacterial solution; S2-2, preparing a cementing solution formed by mixing urea solution and calcium chloride solution; S2-3, using a grouting reinforcement device based on MICP (microbial induced calcium carbonate precipitation) technology to inject a mixed solution of bacterial solution and cementing solution into the broken zone sample to perform grouting reinforcement on the broken zone sample; S2-4. Place the sample after grouting reinforcement at 30±2℃ for 6 days to cure, and obtain the microbial solidified broken zone sample.

9. The method for simulating the leaching of manganese slag leachate and microbial solidification of the broken zone according to claim 6, characterized in that: The S3 specifically includes the following steps: S3-1, open the first water stop clamp (41), close the second water stop clamp (42), use a syringe to inject the manganese slag leachate in step S1 into the liquid replenishment bottle (1) through the liquid replenishment tube (3), and after the manganese slag leachate flows from the overflow port (6) into the overflow liquid collecting cylinder (8), close the first water stop clamp (41); S3-2, placing the microbial solidified broken zone sample obtained in step S2 inside the leaching unit sample mold (9); S3-3, open the second water stop clamp (42), so that the manganese slag leachate fills the sample and flows into the effluent collection cylinder (11) from the upper end of the sample mold (9); S3-4, using a flow rate controller (13) to control the inflow rate of the manganese slag leachate into the liquid inlet bottle (5), to ensure that the outflow rate of the effluent in the microbial solidification and crushing zone into the effluent collecting cylinder (11) is equal; S3-5. Close the second water stop clamp (42) at regular intervals, collect the liquid in the effluent collection cylinder (11), and store it in a refrigerator at 4°C. Then read the liquid volume and calculate the permeability coefficient of the sample.

10. The method for simulating the leaching of manganese slag leachate and microbial solidification of the broken zone according to claim 6, characterized in that: The S4 specifically includes analyzing the changes in the permeability coefficient of the microbial solidified broken zone sample after long-term leaching, and analyzing the changes in the concentration of heavy metal pollutants and environmental risks in the effluent.

Images