Method for repairing mine by using rock weathered artificial soil

Abstract

The invention discloses a method for repairing a mine by using rock weathered artificial soil, and relates to the field of mine repairing. According to the method, the waste slag stone left in the mine history and the waste slag stone generated in the implementation process of mine remediation are effectively utilized, the slag stone is changed into artificial soil by accelerating rock weathering and artificially constructing a soil structure layer, and a plant growing soil layer with the planting capacity, the water and fertilizer retention capacity and sufficient nutrient substances is provided for mine remediation. The method provided by the invention can be effectively connected to a mine restoration engineering link, so that extra cost generated by outward transportation and disposal of the waste slag stone is avoided, and the influence of large-scale exogenous soil dressing on the surrounding environment in the soil sampling process is also avoided. The method for repairing the artificial soil in the mine can give consideration to solid waste utilization, ecological restoration and economic value-added benefits, and has a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of ecological restoration, and specifically is a method for mine restoration by utilizing the original waste slag of the mine to form artificial soil through rock weathering. Background Art

[0002] The root cause of the destruction of the mine environment is the loss of "soil", and mine restoration measures should also start with the restoration of "soil". However, at present, in many historical mines in my country, especially in karst desertification areas, "soil" is a scarce resource, and it is difficult to manage it by importing soil nearby. In the process of mine restoration and historical abandoned mines, a large amount of slag is produced, which cannot be effectively used as block materials and usually needs to be disposed of outside. If soil resources can be obtained on a large scale, low-cost and effective management of mine restoration can be achieved to a large extent.

[0003] Soil is a layered structure formed by weathering of rocks. As the soil formation process proceeds, the parent material undergoes stratification to form different soil layers. The International Soil Science Association proposes to divide the natural soil profile into six main layers: organic layer (O), humus layer (A), eluvial layer (E), sedimentary layer (B), parent material layer (C) and parent rock (R). Traditional mine remediation soil reconstruction usually uses general earth and stone materials for earth and stone engineering construction, which is simply flattened and compacted without forming an effective soil structure, resulting in low productivity of reclaimed soil, failure of reclamation projects or poor results.

[0004] Therefore, it is necessary to provide a method for mine restoration by utilizing rock weathering to form an effective soil layer. Summary of the invention

[0005] The purpose of the present invention is to provide a method for mine restoration using artificial soil made from weathered rocks. The restoration method is intended to start from artificially accelerating the weathering of slag and rock, accelerate the weathering of slag and rock through physical, chemical and biological means, effectively utilize mine waste slag and rock to make soil, and form an effective soil layer for mine restoration. It can also achieve waste utilization of rock slag and self-sufficiency of foreign soil resources, and truly reduce costs and increase efficiency in the process of mine restoration.

[0006] In order to solve the above technical problems, the present invention provides a method for mine restoration using rock weathering artificial soil, which specifically comprises the following steps:

[0007] S1. Mechanically crush the waste slag left in the mine area to be repaired and the slag generated during the mine repair process to a particle size of less than 10 cm; and screen the crushed slag, and the screening particle size is controlled to be less than 2.5 cm, 2.5 cm to 5 cm, and 5 cm to 10 cm;

[0008] S2: Spread three types of slag in order from large to small in the exposed rock mass mining area where soil reconstruction is required, and compact it manually after each layer is spread; the slag with a particle size of 5cm to 10cm shall be laid with a thickness of not less than 30cm, the slag with a particle size of 2.5cm to 5cm shall be laid with a thickness of not less than 20cm, and the slag with a particle size below 2.5cm shall be laid with a thickness of not less than 10cm;

[0009] S3. Install a soil leaching system on the surface of the slag layer, inject acid-based fungus leaching solution into the soil leaching system, and cover the surface of the slag with a polyvinyl chloride transparent film for sealing, and perform leaching cycles for 13 to 20 days; wherein the acid-based fungus leaching solution is 60 to 100 L / m 2 Carry out spraying input;

[0010] S4: peel off the surface polyvinyl chloride film, stop the leaching pump, wait for 20 to 30 hours to pump out the residual liquid, inject silicon-based bacterial culture solution into the soil leaching system, spread dry chicken manure on the surface, and cover the surface with a polyvinyl chloride transparent film for closed fermentation, and perform leaching cycles for 13 to 20 days; wherein, the silicon-based bacterial culture solution in the step is 60 to 100 L / m 2 Sprinkle the chicken manure at 1-2 kg / m 2 To spread;

[0011] S5. Remove the PVC membrane, dismantle the pipe network, till the land, and plant green plants.

[0012] A further technical solution of the present invention is as follows: the acid-based fungus washing solution in step S3 is prepared according to the following method, and the acid-based fungus washing solution is prepared before fungus washing and can be used immediately after preparation. The specific preparation process is as follows:

[0013] S301. Dig up the original soil with a high degree of maturation in the mine area to be repaired, add it to sterilized water at a soil-water ratio of 1:8-10, and shake it until the large soil particles are completely broken up, and then let it stand for more than 30 minutes to clarify it;

[0014] S302. Take the supernatant in step S301 and dilute it with sterile water to prepare 10 -2 concentration of bacterial suspension, at pH = 4-6, the above 10 -2 The bacterial suspension of the concentration was inoculated on Martin's agar medium by spreading method and cultured at a constant temperature of 27-30°C for 3-5 days to obtain a soil fungal community dominated by ascomycetes;

[0015] S303. The soil fungus culture medium in step S302 is punched with a hole puncher to obtain a mycelium block of the soil fungus community mainly composed of ascomycetes, and the mycelium block of the soil fungus community mainly composed of ascomycetes is inoculated into a liquid culture medium to obtain 10-1 The concentration of soil fungal strains mainly composed of Ascomycetes was mixed and homogenized at a speed of 140-160 r / min for 11-13 hours. After homogenization, liquid culture medium was added again to dilute the bacterial solution to obtain 10 -2 A concentration of soil fungal strain liquid mainly composed of ascomycetes is added, and acetic acid and liquid culture medium are added to the mixture and oscillated at a speed of 50 to 70 r / min for 11 to 13 hours to obtain an acid-based fungal washing solution.

[0016] A further technical solution of the present invention: the soil leaching system of step S3 comprises a leaching pipe and a small solar suction pump arranged on the surface of the slag layer; specifically, the leaching pipes are laid in a square grid at the same intervals on the surface of the slag layer, and solar suction pumps are arranged at intervals at the intersections of the leaching pipe nodes, the pump pipe inlet extends to the bottom impermeable bedrock layer, and the pump pipe outlet is tightly overlapped with the leaching pipe to form a soil leaching system.

[0017] A further technical solution of the present invention is as follows: the silicon-based bacterial culture solution in step S4 is prepared according to the following method before the bacteria are washed, and is ready for use. The specific preparation method is as follows:

[0018] S401. Dig up native soil with a high degree of maturation in the mine area to be repaired, add it to sterilized water at a soil-water ratio of 1:8-10, and shake it until the large soil particles are completely broken up, and then let it stand for more than 30 minutes to clarify it;

[0019] S402. Take the supernatant in step S401 and dilute it to 10 with sterile water. -6 concentration, under the condition of pH=7-10, the above 10 -6 The bacterial suspension of the concentration was inoculated into beef extract peptone medium by spreading method, and cultured at 34-36°C for 2-3 days to obtain soil bacterial community dominated by Bacillus and Gram-positive bacteria;

[0020] S403. Using an inoculation needle, pick soil bacterial colonies of different forms, mainly Bacillus and Gram-positive bacteria, from the soil bacterial community culture medium in the above step S402, and inoculate them into a liquid culture medium to obtain 10 -1 The concentration of soil bacterial strains mainly composed of Bacillus and Gram-positive bacteria was mixed and homogenized at a speed of 140-160 r / min for 11-13 hours. After homogenization, liquid culture medium was added again to dilute the bacterial solution to obtain 10 -2 A soil bacterial strain solution with a concentration mainly consisting of Bacillus and Gram-positive bacteria is added with silica sol and liquid culture medium, and the mixture is oscillated and homogenized at a speed of 50 to 70 r / min for 11 to 13 hours to obtain a silica-based bacterial culture solution.

[0021] The preferred technical solution of the present invention is: the liquid culture medium for preparing the acid-based fungus eluent in S303 is selected from Sabouraud liquid culture medium, and the acetic acid concentration is 0.01 mol / L; 10 -2 The volume of the liquid containing soil fungal strains mainly composed of Ascomycetes is 10%-20%, the volume of acetic acid is 20%-40%, and the volume of the liquid culture medium is 50%-60%.

[0022] The preferred technical solution of the present invention is as follows: the elution pipe is made of PVC material, holes are opened on the pipe wall every 50 cm, and the elution pipes are laid at a spacing of 2 to 5 m.

[0023] The preferred technical solution of the present invention is: the liquid culture medium for preparing the silicon-based bacterial culture solution in S403 is selected from beef extract peptone liquid culture medium, and the silica sol concentration is selected to be 25%; wherein, the 10 -2 The volume of the liquid containing soil bacterial strains mainly consisting of Bacillus and Gram-positive bacteria accounts for 20% to 30%, the volume of the silica sol accounts for 50% to 60%, and the volume of the liquid culture medium accounts for 20% to 30%.

[0024] The liquid culture medium for preparing the acid-based fungal eluent in the present invention is Sabouraud Dextrose Broth (SDB), and the liquid culture medium for preparing the silicon-based bacterial culture solution is beef extract peptone liquid culture medium. Both culture media are existing culture media, and their formulas are public.

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

[0026] (1) The present invention recycles and utilizes waste rock slag from mines during the mine restoration process, and artificially intervenes in the natural weathering of rocks. Physical crushing methods are used to replace the physical weathering process in which rocks are transformed from large blocks into small fragments through long-term effects such as thermal expansion and contraction, ice splitting, and layer cracking in the natural state of rocks. Acetic acid is then added to replace a series of effects such as long-term dissolution, hydrolysis, hydration, and oxidation of carbon dioxide in the natural state. The weathering mechanism of organic acids on rock minerals includes proton promotion effect and complex promotion effect, and organic acids form soluble chelates with base ions in rock minerals, thereby causing strong dissolution of rock minerals.

[0027] (2) The present invention also adds soil fungi and bacterial flora and provides sufficient nutrients for their growth, thereby avoiding the problem that the growth of microorganisms is limited due to lack of nutrients in the early stage of rock weathering under natural conditions, and the biological weathering effect is not obvious. The microorganisms are allowed to grow on the surface and in the cracks of the slag. The drilling network formed by the microbial community can enhance the effective surface area of ​​rock chemical dissolution and cause its surface strength to weaken, thereby promoting mechanical erosion. The organic acids secreted by the microorganisms and the CO2 released by the respiration of the microorganisms acidify the surface moisture of the rock and also accelerate the decomposition of rock minerals. At the same time, because the flora are all taken from the surrounding environment, the soil ecology formed is also conducive to plant growth.

[0028] The present invention recycles waste mine slag during the mine restoration process, greatly shortens the weathering time of rocks through the multiple combined use of physical, chemical and biological means, and forms a soil ecological structure with the same properties as the original soil. The residual rock debris in the soil structure can interact with carbon dioxide as the mine restoration progresses, be mineralized and finally stored in the form of carbonate, thereby achieving energy conservation and carbon reduction effects. On the one hand, the present invention avoids large-scale exogenous soil and saves the cost of covering soil materials for mine restoration projects. On the other hand, the soil structure is constructed based on the concept of soil reconstruction, forming a sustainable development simulated natural soil layer with sufficient biological communities, planting capacity and ecological value, thereby improving the durability of the soil's water and fertilizer retention capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the process of preparing artificial soil for mine restoration of the present invention;

[0030] Figure 2 It is a structural schematic diagram of the soil washing system in the present invention;

[0031] Figure 3 It is the plan layout diagram of the soil washing system in the present invention.

[0032] Explanation of the accompanying drawings: 1—solar suction pump; 2—suction pump pipe; 3—rinsing pipe; 4—slag layer. DETAILED DESCRIPTION

[0033] The technical scheme in the embodiment of the present invention is described clearly and completely below in conjunction with the accompanying drawings in the embodiment of the present invention. In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0034] The soil washing system in the embodiment, such as Figure 2 and Figure 3As shown, it includes a leaching pipe 3 arranged on the surface of the slag layer 4 and a plurality of small solar suction pumps 1. The solar suction pump 1 is a water pump powered by solar energy and is an existing device. The leaching pipes 3 are laid on the surface of the slag layer 4 in a grid-like manner at the same spacing. The leaching pipes are made of PVC material, and holes are opened on the pipe wall every 50 cm. The leaching pipes are laid at a spacing of 2 to 5 m. Solar suction pumps 1 are arranged at intervals at the intersection of the nodes of the grid-type leaching pipes. The pump pipe inlet extends to the impermeable bedrock layer at the bottom of the slag layer 4, and the pump pipe outlet is tightly overlapped with the leaching pipe 3 to form a soil leaching system.

[0035] The acid-based fungal washing liquid described in the following examples is prepared according to the following method, and the acid-based fungal washing liquid is prepared before fungal washing and can be used immediately after preparation. The specific preparation process is as follows:

[0036] (1) Dig up the original soil with a high degree of maturation in the mine area to be repaired, add it to sterilized water at a soil-water ratio of 1:8-10, and shake it until the large soil particles are completely broken up, then let it stand for more than 30 minutes to clarify it;

[0037] (2) Take the supernatant in step (1) and dilute it with sterile water to prepare 10 -2 concentration of bacterial suspension, at pH = 4-6, the above 10 -2 The bacterial suspension of the concentration was inoculated on Martin's agar medium by spreading method and cultured at a constant temperature of 27-30°C for 3-5 days to obtain a soil fungal community dominated by ascomycetes;

[0038] (3) Using a hole puncher to punch holes in the soil fungus culture medium in step (2), a mycelial block of a soil fungus community dominated by ascomycetes is obtained, and the mycelial block of a soil fungus community dominated by ascomycetes is inoculated into a liquid culture medium to obtain 10 -1 The concentration of soil fungal strains mainly composed of Ascomycetes was mixed and homogenized at a speed of 140-160 r / min for 11-13 hours. After homogenization, liquid culture medium was added again to dilute the bacterial solution to obtain 10 -2 A concentration of soil fungal strain liquid mainly composed of ascomycetes is added, and acetic acid and liquid culture medium are added to the mixture and oscillated at a speed of 50 to 70 r / min for 11 to 13 hours to obtain an acid-based fungal washing solution.

[0039] The silicon-based bacterial culture solution in the embodiment is prepared according to the following method before bacterial elution, and is ready for use. The specific preparation method is as follows:

[0040] (1) Dig up native soil with a high degree of maturation in the mine area to be repaired, add it to sterilized water at a soil-water ratio of 1:8-10, and shake it until the large soil particles are completely broken up, then let it stand for more than 30 minutes to clarify it;

[0041] (2) Take the supernatant in step (1) and dilute it to 10 -6 concentration, under the condition of pH=7-10, the above 10 -6 The bacterial suspension of the concentration was inoculated into beef extract peptone medium by spreading method, and cultured at 34-36°C for 2-3 days to obtain soil bacterial community dominated by Bacillus and Gram-positive bacteria;

[0042] (3) Using an inoculation needle, pick soil bacterial colonies of different forms, mainly Bacillus and Gram-positive bacteria, from the soil bacterial community culture medium in step (2) above, and inoculate them into a liquid culture medium to obtain 10 -1 The concentration of soil bacterial strains mainly composed of Bacillus and Gram-positive bacteria was mixed and homogenized at a speed of 140-160 r / min for 11-13 hours. After homogenization, liquid culture medium was added again to dilute the bacterial solution to obtain 10 -2 A soil bacterial strain solution with a concentration mainly consisting of Bacillus and Gram-positive bacteria is added with silica sol and liquid culture medium, and the mixture is oscillated and homogenized at a speed of 50 to 70 r / min for 11 to 13 hours to obtain a silica-based bacterial culture solution.

[0043] Example 1 provides a method for mine restoration using rock weathering artificial soil, and the specific steps are as follows:

[0044] S1. Crushing and screening of slag: The original soil and slag of the mine to be repaired is mechanically crushed by a ball mill to a particle size specification of no more than 10cm, and the crushed soil and slag is screened into three specifications of particle size: 0-2.5cm, 2.5cm-5cm, and 5cm-10cm.

[0045] S2. Layered paving: appropriately level and clean the exposed rock mass of the mine to be repaired and the mine reclamation area, and pave the three specifications in order from large to small in particle size: 30 cm thick for 5-10 cm slag, 20 cm thick for 2.5 cm slag, and 10 cm thick for slag below 2.5 cm. After each layer is paved, roll it manually once before paving the upper layer to form a 10 m2 experimental plot.

[0046] S3. Installation of leaching system: Lay leaching pipes on the surface of the experimental field at intervals of 2m×2m, connect suction pumps at the corners of the grid, and set the suction pumps at intervals.

[0047] S4. Acid-based fungus leaching: Inject the acid-based fungus leaching solution into the soil leaching system, and evenly sprinkle the acid-based fungus leaching solution on the experimental field through the leaching system, and cover the surface of the slag with a polyvinyl chloride transparent film for sealing treatment, and perform leaching cycles for 14 days; the acid-based fungus leaching solution is 60-100L / m 2 Carry out spraying input;

[0048] S5. Silicon-based bacteria leaching: remove the surface polyvinyl chloride film, stop the leaching pump, wait for one day to remove the residual effluent, inject silicon-based bacteria culture solution into the soil leaching system, spread dry chicken manure on the surface, and cover the surface with a polyvinyl chloride transparent film for closed fermentation, and perform leaching cycles for 14 days; the silicon-based bacteria culture solution in the step is 60-100L / m 2 Sprinkle the chicken manure at 1-2 kg / m 2 To spread;

[0049] S6. Soil formation: remove the polyvinyl chloride membrane, dismantle the pipe network, and properly clean and trim the surface.

[0050] The method for mine restoration using weathered rock artificial soil provided in Example 2 is different from that in Example 1 in that the slag is not screened after crushing and is spread in layers:

[0051] The mine slag was mechanically crushed by ball mill to a particle size no larger than 10 cm, and directly spread on the exposed rock mine reclamation area to form a 10 m2 experimental plot with a total thickness of 60 cm.

[0052] The method for mine restoration using rock weathering artificial soil provided in Example 3 is different from that in Example 1 in that the acid-based fungus leaching is not performed: after the leaching system is installed, the silicon-based bacteria leaching is directly performed. After the silicon-based bacteria leaching is completed, the suction pump is stopped, the soil is covered with a transparent film of polyvinyl chloride and sealed, and left to stand for 14 days.

[0053] The method for mine restoration using rock weathering artificial soil provided in Example 4 is different from that in Example 1 in that the silicon-based bacteria leaching is not performed. After the acid-based fungus leaching is completed, the suction pump is stopped, the soil is covered with a transparent film of vinyl chloride and sealed, and left to stand for 14 days.

[0054] Verification test

[0055] Experimental group: alfalfa was cultivated for 10 hours and grass seeds were sown in the experimental field constructed in Example 1-4, and watered and maintained for 3 days to keep alive, and then allowed to grow naturally;

[0056] Control group: Alfalfa was cultivated and grass seeds were sown in external imported soil fields, and after watering and curing for 3 days to keep it alive, it was allowed to grow naturally; other conditions remained unchanged.

[0057] After 30 days, the survival rate, plant height and grass coverage of alfalfa were recorded, as shown in Table 1.

[0058] serial number Number of surviving alfalfa plants Average plant height (m) Grassland coverage (%) Example 1 10 16 95 Example 2 10 13 71 Example 3 8 12 82 Example 4 7 10 76 Hakka 8 14 90

[0059] It can be seen from Table 1 that the soil structure prepared by the present invention has a better natural growth effect on plants than vegetation grown in foreign soil, and observation of the growth process found that the alfalfa leaves prepared by the soil structure of the present invention are bright green, the soil has good water retention performance, and the soil fertility is long-lasting, which effectively promotes the growth of alfalfa.

[0060] Comparing the results of Example 1 and Example 2 with the actual growth conditions on site, the soil structure constructed without screening and layering cannot guarantee vegetation growth and effective coverage in areas with large boulders on the surface due to the uneven distribution of slag. Therefore, screening and layering to construct the soil structure framework is particularly important.

[0061] Comparing the results of Example 1 and Example 3 and the actual growth conditions on site, the soil structure that was not eluted with the acid-based fungus elution solution had poor water retention performance and the plants turned yellow because the elution solution leached the rocks, eluted the soluble salts, colloids and fine soil particles to the bottom, formed the original sedimentation layer, and retained the moisture in the soil to a great extent. Therefore, elution with the acid-based fungus elution solution is particularly important in soil composition.

[0062] Comparing the results of Example 1 and Example 4 and the actual growth conditions on site, the soil structure without leaching with the silicon-based bacterial leaching solution lacks fertility and has poor growth effect. Because bacteria play a very important role in soil formation, nutrient circulation, and crop growth, such as organic matter decomposition, biotransformation, and nitrogen fixation, leaching with the silicon-based bacterial leaching solution is particularly important in soil formation.

Claims

1. A method for mine restoration using rock weathering artificial soil, characterized in that: The specific steps include: S1. Mechanically crush the waste slag left in the mine area to be repaired and the slag generated during the mine repair process to a particle size of less than 10 cm; and screen the crushed slag, and the screening particle size is controlled to be less than 2.5 cm, 2.5 cm to 5 cm, and 5 cm to 10 cm; S2: Spread three types of slag in order from large to small in the exposed rock mass mining area where soil reconstruction is required, and compact it manually after each layer is spread; the slag with a particle size of 5cm to 10cm shall be laid with a thickness of not less than 30cm, the slag with a particle size of 2.5cm to 5cm shall be laid with a thickness of not less than 20cm, and the slag with a particle size below 2.5cm shall be laid with a thickness of not less than 10cm; S3. Install a soil leaching system on the surface of the slag layer, inject acid-based fungus leaching solution into the soil leaching system, and cover the surface of the slag with a polyvinyl chloride transparent film for sealing, and perform leaching cycles for 13 to 20 days; wherein the acid-based fungus leaching solution is 60 to 100 L / m 2 Carry out spraying input; S4: peel off the surface polyvinyl chloride film, stop the leaching pump, wait for 20 to 30 hours to pump out the residual liquid, inject silicon-based bacterial culture solution into the soil leaching system, spread dry chicken manure on the surface, and cover the surface with a polyvinyl chloride transparent film for closed fermentation, and perform leaching cycles for 13 to 20 days; wherein, the silicon-based bacterial culture solution in the step is 60 to 100 L / m 2 Sprinkle the chicken manure at 1-2 kg / m 2 To spread; S5. Remove the PVC membrane, dismantle the pipe network, till the land, and plant green plants.

2. The method for mine restoration using rock weathering artificial soil according to claim 1, characterized in that: The acid-based fungus washing liquid in step S3 is prepared according to the following method, and the acid-based fungus washing liquid is prepared before fungus washing and can be used immediately after preparation. The specific preparation process is as follows: S301. Dig up the original soil with a high degree of maturation in the mine area to be repaired, add it to sterilized water at a soil-water ratio of 1:8-10, and shake it until the large soil particles are completely broken up, and then let it stand for more than 30 minutes to clarify it; S302. Take the supernatant in step S301 and dilute it with sterile water to prepare 10 -2 concentration of bacterial suspension, at pH = 4-6, the above 10 -2 The bacterial suspension of the concentration was inoculated on Martin's agar medium by spreading method and cultured at a constant temperature of 27-30°C for 3-5 days to obtain a soil fungal community dominated by ascomycetes; S303. The soil fungus culture medium in step S302 is punched with a hole puncher to obtain a mycelium block of the soil fungus community mainly composed of ascomycetes, and the mycelium block of the soil fungus community mainly composed of ascomycetes is inoculated into a liquid culture medium to obtain 10 -1 The concentration of soil fungal strains mainly composed of Ascomycetes was mixed and homogenized at a speed of 140-160 r / min for 11-13 hours. After homogenization, liquid culture medium was added again to dilute the bacterial solution to obtain 10 -2 A concentration of soil fungal strain liquid mainly composed of ascomycetes is added, and acetic acid and liquid culture medium are added to the mixture and oscillated at a speed of 50 to 70 r / min for 11 to 13 hours to obtain an acid-based fungal washing solution.

3. A method for mine restoration using rock weathering artificial soil according to claim 1 or 2, characterized in that: The soil leaching system of step S3 includes leaching pipes and a small solar suction pump arranged on the surface of the slag layer; specifically, the leaching pipes are laid in a square grid at the same intervals on the surface of the slag, and solar suction pumps are arranged at intervals at the intersections of the leaching pipe nodes. The pump pipe inlet extends to the bottom impermeable bedrock layer, and the pump pipe outlet is tightly overlapped with the leaching pipe to form a soil leaching system.

4. A method for mine restoration using weathered rock artificial soil according to claim 1 or 2, characterized in that: The silicon-based bacterial culture solution in step S4 is prepared according to the following method before the bacteria are washed, and is ready for use. The specific preparation method is as follows: S401. Dig up native soil with a high degree of maturation in the mine area to be repaired, add it to sterilized water at a soil-water ratio of 1:8-10, and shake it until the large soil particles are completely broken up, and then let it stand for more than 30 minutes to clarify it; S402. Take the supernatant in step S401 and dilute it to 10 with sterile water. -6 concentration, under the condition of pH=7-10, the above 10 -6 The bacterial suspension of the concentration was inoculated into beef extract peptone medium by spreading method, and cultured at 34-36°C for 2-3 days to obtain soil bacterial community dominated by Bacillus and Gram-positive bacteria; S403. Using an inoculation needle, pick soil bacterial colonies of different forms, mainly Bacillus and Gram-positive bacteria, from the soil bacterial community culture medium in the above step S402, and inoculate them into a liquid culture medium to obtain 10 -1 The concentration of soil bacterial strains mainly composed of Bacillus and Gram-positive bacteria was mixed and homogenized at a speed of 140-160 r / min for 11-13 hours. After homogenization, liquid culture medium was added again to dilute the bacterial solution to obtain 10 -2 A soil bacterial strain solution with a concentration mainly of Bacillus and Gram-positive bacteria is added with silica sol and liquid culture medium, and the mixture is oscillated and homogenized at a speed of 50 to 70 r / min for 11 to 13 hours to obtain a silica-based bacterial culture solution.

5. The method for mine restoration using weathered rock artificial soil according to claim 2, characterized in that: The liquid culture medium for preparing the acid-based fungus eluent in S303 is selected from Sabouraud liquid culture medium, and the acetic acid concentration is 0.01 mol / L; 10 -2 The volume of the liquid containing soil fungal strains mainly composed of Ascomycetes is 10%-20%, the volume of acetic acid is 20%-40%, and the volume of the liquid culture medium is 50%-60%.

6. The method for mine restoration using weathered rock artificial soil according to claim 3, characterized in that: The elution pipe is made of PVC material, and holes are opened on the pipe wall every 50 cm. The elution pipes are laid at a spacing of 2 to 5 m.

7. The method for mine restoration using weathered rock artificial soil according to claim 4, characterized in that: In said S403, the liquid culture medium for preparing the silica-based bacterial culture solution is selected from beef extract peptone liquid culture medium, and the silica sol concentration is selected to be 25%; wherein said 10 -2 The volume of the liquid containing soil bacterial strains mainly consisting of Bacillus and Gram-positive bacteria accounts for 20% to 30%, the volume of the silica sol accounts for 50% to 60%, and the volume of the liquid culture medium accounts for 20% to 30%.

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