Coal-based solid waste eco-restoration material and preparation method thereof
The use of inorganic nano-seed crystals and microbial agents in a physical foaming process addresses the structural and pollution issues of coal-based waste materials, enhancing soil fertility and safety in eco-restoration.
Patent Information
- Authority / Receiving Office
- AU · AU
- Patent Type
- Applications
- Current Assignee / Owner
- TAIYUAN UNIVERSITY OF TECHNOLOGY
- Filing Date
- 2025-03-04
- Publication Date
- 2026-07-09
AI Technical Summary
Existing coal-based solid waste eco-restoration materials face issues such as excessive pores, poor structure, low water retention, and heavy metal pollution, exacerbated by chemical foaming methods that are costly and unsafe.
A method involving the preparation of a coal-based solid waste eco-restoration material using inorganic nano-seed crystals, cementitious materials, and composite microbial agents, combined with physical foaming technology to create a porous sandy loam matrix, which is then mixed with coal slime and fermented to enhance soil fertility and reduce heavy metal toxicity.
The method strengthens soil structure, improves water retention and air permeability, reduces heavy metal mobility, and ensures safe, cost-effective production, suitable for eco-restoration applications.
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Abstract
Description
FIELD
[0001] The present disclosure relates to the technical field of resource utilization of coal gangue, in particular to a coal-based solid waste eco-restoration material and preparation method thereof. BACKGROUND
[0002] With the continuous development of coal mining and washing industry, a large number of coal-based solid wastes, especially coal gangue, slime, and fly ash, have become one of the biggest environmental and resource challenges in China. As a by-product of coal mining, coal gangue accounts for 10-15% of raw coal output, and a storage capacity has exceeded 7 billion tons at present. Coal gangue piled up randomly for a long time not only encroaches on land resources, destroys ecological environment, but also brings serious air, water and soil pollution, and even causes geological disasters, endangering human safety. Similarly, due to the high water content and complex composition of coal slime, it is easy to cause sediment deposition and water pollution after stacking, and fly ash, as a main by-product of coal-fired power plants, has an annual emission of 790 million tons, so the ecological and environmental pressure brought by stacking can not be ignored.
[0003] Coal-based solid waste is not only complex in composition, but also has a potential risk of heavy metal pollution. However, these wastes contain ingredients similar to soil, and have great potential in eco-restoration and soil improvement in mining areas. At the national level, we actively advocate the comprehensive utilization of solid waste resources and promote its application in ecorestoration. Patent of "an activated coal gangue-based compressed ecological soil and preparation method thereof" of CN118303294A improves the fertility and weatherability of coal gangue, improves the soil structure, and makes it a compressed ecological soil with more ecological 2025201577 04 Mar 2025 adaptability by adding compost and organic water-retaining materials. Patent of "a coal gangue soil improvement structure" of CN219719044U proposes a scheme of improving saline-alkali soil through multi-layer structure, in which materials such as coal gangue powder layer, microbial bacteria layer, straw layer and plant ash layer are laid on the soil layer in turn. The structure effectively reduces the cost of soil improvement, and at the same time enhances the rooting ability of vegetation and improves the ability to resist sandstorms. However, there are many shortcomings in the existing utilization technology. For example, simple mixing of coal gangue and raw soil can easily lead to excessive pores, poor structure, low water retention capacity and insufficient fertility, which cannot provide an ideal growth environment for plants. In addition, the problem of heavy metal pollution in solid waste has not been effectively solved.
[0004] Therefore, the existing technology needs further improvement and promotion. SUMMARY
[0005] In view of the above-mentioned deficiencies in the prior art, the present disclosure is to provide a coal-based solid waste eco-restoration material and a preparation method thereof, aiming to solve the difficult industrialization of the existing coal-based solid waste ecological restoration materials due to the need to use a chemical foaming method in the preparation process, the porous material is easy to collapse, poor water retention, and heavy metal pollution.
[0006] To solve the defects, the present disclosure adopts the following schemes.
[0007] In a first aspect, a method for preparing a coal-based solid waste eco-restoration material includes:
[0008] mixing and placing calcium oleate, sodium silicate, polyvinylpyrrolidone, oleylamine, anhydrous ethanol, and water in a hydrothermal reactor, heating at a constant temperature, centrifuging, and washing to collect inorganic nano-seed crystal;
[0009] seeding the inorganic nano-seed crystal to form a cementitious material; mixing coal gangue powder with the cementitious material, mineral activator, and physical pore-forming foam, then curing, crushing, and screening to prepare a porous sandy loam matrix; 2025201577 04 Mar 2025
[0010] uniformly mixing the prepared porous sandy loam matrix, coal slime, and composite microbial agent, and then fermenting and maturing to obtain the coal-based solid waste ecorestoration material.
[0011] The following are preferred technical schemes of the present disclosure, but it does not limit the technical schemes provided by the present disclosure. Through the following preferred technical schemes, the purpose and beneficial effects of the present disclosure can be better achieved and realized.
[0012] In the method for preparing a coal-based solid waste eco-restoration material, a calciumsilicon ratio of the calcium oleate to the sodium silicate is 0.6-1.6, and a hydrothermal reaction temperature is 120-180 °C for 4 hours to 12 hours.
[0013] In the method for preparing a coal-based solid waste eco-restoration material, the porous sandy loam matrix comprises, in parts by weight, 50-80 parts of the coal gangue powder, 10-40 parts of the cementitious material, 5-10 parts of the mineral activator, 1-8 parts of physical poreforming foam, and a water-cement ratio is 0.5-0.7.
[0014] In the method for preparing a coal-based solid waste eco-restoration material, the cementitious material includes, in parts by weight, 2-5 parts of inorganic nano-seed crystal, 50-70 parts of fly ash, 5-10 parts of sodium phosphate, 10-25 parts of calcium oxide, and 5-20 parts of sodium hydroxide.
[0015] In the method for preparing a coal-based solid waste eco-restoration material, the physical pore-forming foam includes a foaming agent and a foam stabilizer, an added mass of the foam stabilizer is 20%-50%; the foaming agent is selected from one or more of sodium dodecyl sulfate, fatty alcohol polyoxyethylene ether sodium sulfate, ethoxylated alkyl sodium sulfate, and sodium dodecyl polyoxyethylene ether succinate; the foam stabilizer is selected from hydroxypropyl methylcellulose and polyvinyl alcohol.
[0016] In the method for preparing a coal-based solid waste eco-restoration material, the mineral activator includes slag, desulfurized gypsum, and carbide slag, and in parts by weight, an added ratio of each component is (2-4): (1-2): (1-2). 2025201577 04 Mar 2025
[0017] In the method for preparing a coal-based solid waste eco-restoration material, a mass ratio of the porous sandy loam matrix to the coal slime is 1: (1-2); an added amount of the composite microbial agent is 0.05%-2% mass percentage, a fermenting time is 14-21 days, and a maturing time is 7-14 days.
[0018] In the method for preparing a coal-based solid waste eco-restoration material, the composite microbial agent comprises bacteria and fungi, and the bacteria are selected from one or more of Bacillus mucilaginosus, Bacillus licheniformis, Bacillus megaterium, Bacillus velezensis, and Acidithiobacillus ferrooxidans; the fungi comprise Arbuscular mycorrhizal fungi and Trichoderma fungi.
[0019] In a second aspect, a coal-based solid waste eco-restoration material, which is prepared by the method for preparing the coal-based solid waste eco-restoration material.
[0020] In a third aspect, an application of the coal-based solid waste eco-restoration material, which is used as artificial soil for environment eco-restoration.
[0021] Beneficial effects: compared with the existing technology, in the present disclosure, coal gangue is used as a main raw material, mixed with cementitious materials and mineral activators, and the porous sandy loam matrix of coal-based solid waste is prepared by physical foaming technology through curing, crushing and particle size grading. In the present disclosure, the selfdeveloped inorganic nano-seeds can accelerate the process of hydration reaction and the formation of cementitious materials through nucleation and sowing. With the addition of cementitious materials, it is beneficial to strengthen the skeleton strength of sandy soil matrix, reduce the collapse of pore channels during crushing, and improve the water retention and permeability of materials. Moreover, the cementing material solidifies the heavy metals in the coal gangue, effectively reducing the content of the most mobile weak acid extracted heavy metals, and transforming it into a residue state which is not easy to migrate and has weak biological toxicity. Compared with the traditional aluminum powder chemical foaming and strong acid foaming, the physical foaming technology adopted in the present disclosure improves the safety of operation while reducing the cost, and is convenient for standardized production. Then, the porous sandy loam matrix is mixed with coal slime and composite microbial agents, and the coal-based solid 2025201577 04 Mar 2025 waste eco-restoration material is prepared through fermentation and sedimentation. The nutrient elements in the eco-restoration materials can be fully released through the activation of compound microbial agents, and the fertility can be improved. In one aspect, the forms and availability of heavy metals in soil are changed by secreting chelates and redox reactions, and the heavy metal pollution is reduced by cooperating with sandy soil matrix. In another aspect, the compound microbial inoculum can promote the formation of soil aggregates, improve the water retention and air permeability of soil, and facilitate plant growth. At the same time, it will not cause secondary pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a schematic flow chart of a method for preparing the coal-based solid waste ecorestoration material provided in the present disclosure.
[0023] FIG. 2 is a schematic diagram of a network structure support system formed by inorganic nanogel and hydration products in coal-based solid waste porous sandy loam matrix.
[0024] FIG. 3 is a schematic diagram of XRD patterns of inorganic nano-seed crystal crystals synthesized under different conditions in coal-based solid waste porous sandy loam matrix.
[0025] FIG. 4 is a schematic diagram of FTIR patterns of inorganic nano-seed crystal crystals synthesized under different conditions in coal-based solid waste porous sandy loam matrix, which proves that the synthesis of inorganic nano-seed crystal C-S-H promotes the hydration speed and strength development of gel materials. DETAILED DESCRIPTION OF EMBODIMENTS
[0026] The present disclosure provides a coal-based solid waste eco-restoration material and a preparation method and present disclosure thereof. In order to make the purpose, technical schemes and effect of the present disclosure more clear and definite, the present disclosure is further described in detail below. It should be understood that the specific embodiments described here are only for explaining the present disclosure, and are not used to limit the present disclosure. 2025201577 04 Mar 2025
[0027] It can be understood by those skilled in the art that the singular forms "a", "an", and "the" used herein can also include plural forms unless specifically stated. It should be further understood that the word "comprise" and "include" used in the specification of the present disclosure refers to the presence of the described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations. It should be understood that the term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.
[0028] It can be understood by those skilled in the art that unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which the present disclosure belongs. It should also be understood that terms, such as those defined in general dictionaries, should be understood to have meanings consistent with those in the context of the prior art, and are not interpreted in an idealized or overly formal sense unless they are specifically defined as here.
[0029] It should be understood that the sequence number and size of each step in the embodiments do not mean the order of execution, and the order of execution of each process is determined by its function and internal logic, and should not constitute any restrictions on the implementation process of this embodiment of the present disclosure. The instruments used are all commercially available products.
[0030] As shown in FIG. 1, a method for preparing a coal-based solid waste eco-restoration material provided in the present disclosure includes the following steps:
[0031] S10, mixing and placing calcium oleate, sodium silicate, polyvinylpyrrolidone, oleylamine, anhydrous ethanol and water in a hydrothermal reactor, heating at a constant temperature, centrifuging, and washing to collect inorganic nano-seed crystal.
[0032] In the step, the nano-seeds crystal is prepared by two-phase interface method. Combined with FIG. 2, a lot of broken bonds and structural defects are existing on a surface of the nano-seeds crystal, which can be used as a new nucleation site, greatly reducing a nucleation barrier and promoting formation of cementitious materials. 2025201577 04 Mar 2025
[0033] S20, seeding the inorganic nano-seed crystal to form a cementitious material; mixing coal gangue powder with the cementitious material, mineral activator, and physical pore-forming foam, then curing, crushing, and screening to prepare a porous sandy loam matrix.
[0034] In the embodiment, an addition of the cementitious material is beneficial to strengthen a skeleton strength of the sandy loam matrix, reduce collapse of pore channels during crushing, and improve water retention and air permeability of the material. Moreover, the cementitious material solidifies and coats heavy metals in the coal gangue, which effectively reduces a content of the most mobile weak acid extracted heavy metals and transforms them into a residue state which is not easy to migrate and has weak biological toxicity. Compared with the traditional aluminum powder chemical foaming and strong acid foaming, the physical foaming technology adopted in the embodiment improves the safety of operation while reducing the cost, which is convenient for standardized production.
[0035] S30, uniformly mixing the prepared porous sandy loam matrix, coal slime, and composite microbial agent, and then fermenting and maturing to obtain the coal-based solid waste ecorestoration material.
[0036] In the embodiment, nutrient elements in the eco-restoration material can be fully released through an activation of the composite microbial agent, and at the same time, a formation of soil aggregates is enhanced, the fertility and water retention of the eco-restoration material are improved, which is beneficial to plant growth. The eco-restoration material can be applied to fields of mine soil restoration, land reclamation, etc.
[0037] The above technical schemes provided in the present disclosure are further explained by specific preparation methods.
[0038] Embodiment 1
[0039] Coal gangue was put into a ball mill, a frequency of the ball mill was set at 40 Hz, and a ball milling time was 30 minutes, and the resulting sample was sieved through a 10-mesh screen.
[0040] 60 parts of fly ash, 3 parts of seed crystal, 10 parts of sodium phosphate, 12 parts of calcium oxide, and 15 parts of sodium hydroxide were weighed and mixed with water to form a 2025201577 04 Mar 2025 slurry, and cured for 3 hours at a temperature of 35 °C to obtain a self-made cementitious material. The mineral activator was prepared from slag, desulfurized gypsum, and carbide slag according to a mass ratio of 2: 1: 2. Sodium dodecyl sulfate and hydroxypropyl methylcellulose were weighed and added in turn according to a mass ratio of 1: 1, and stirred (600 r / min) for 15 minutes each to form foam slurry. 60 parts of coal gangue powder, 25 parts of self-made cementitious material, and 8 parts of mineral activator were mixed to form slurry, and 7 parts of the foam slurry was added to mix evenly, cured at 35 °C for 72 hours, demoulded and dried, crushed and screened to obtain coal-based solid waste porous sandy loam matrix material with particle size below 5 mm.
[0041] The obtained coal-based solid waste porous sandy loam matrix material and coal slime were mixed according to a ratio of 1:1, and 0.5% composite microbial agent was added. The composite microbial agent was consisted of Bacillus mucilaginosus, Bacillus velezensis and Trichoderma harzianum with an addition ratio of 1: 1: 1. fermented for 14 days, and precipitated for 7 days to obtain the coal-based solid waste eco-restoration material.
[0042] Embodiment 2
[0043] The coal gangue was put into a ball mill, and a frequency of the ball mill was set at 50 Hz, and the ball milling time was 60 minutes, and the resulting sample was sieved through an 18-mesh screen.
[0044] 56 parts of fly ash, 4 parts of seed crystal, 10 parts of sodium phosphate, 10 parts of calcium oxide, and 20 parts of sodium hydroxide were weighed and mixed with water to form a slurry, and cured for 3 hours at a temperature of 40 °C to obtain a self-made cementitious material. A mineral activator was prepared from slag, desulfurized gypsum, and carbide slag according to a mass ratio of 3: 2: 1. Sodium dodecyl sulfate, sodium dodecyl polyoxyethylene ether succinate, and hydroxypropyl methylcellulose were weighed and added in turn according to a mass ratio of 2: 1: 1, and stirred (600 r / min) for 10 minutes each to form foam slurry. 56 parts of coal gangue powder, 30 parts of self-made cementitious material, and 6 parts of mineral activator were mixed to form slurry, and 8 parts of the foam slurry was added to mix evenly, cured at 60 °C for 48 hours, demoulded and dried, crushed and screened to obtain coal-based solid waste porous sandy loam matrix material with particle size below 5 mm. 2025201577 04 Mar 2025
[0045] The obtained coal-based solid waste porous sandy loam matrix material and coal washing by-products were mixed according to a ratio of 1:1.5, and 1.5% of composite microbial agent (1% of Bacillus mucilaginosus, Bacillus licheniformis, and Bacillus megaterium in total, 0.5% of Trichoderma harzianum) was added and fermented for 16 days, and precipitated for 9 days to obtain the coal-based solid waste eco-restoration material.
[0046] Embodiment 3
[0047] Coal gangue was put into a ball mill, a frequency of the ball mill was set at 50 Hz, and a ball milling time was 90 minutes, and the resulting sample was sieved through a 30-mesh screen.
[0048] 50 parts of fly ash, 5 parts of seed crystal, 10 parts of sodium phosphate, 24 parts of calcium oxide and 11 parts of sodium hydroxide were weighed and mixed with water to form a slurry, and cured for 5 hours at a temperature of 50 °C to obtain a self-made cementitious material. The mineral activator was prepared from slag, desulfurized gypsum, and carbide slag according to a mass ratio of 2:2:1. Sodium dodecyl sulfate hydroxypropyl methylcellulose and polyvinyl alcohol were weighed and added in turn according to a mass ratio of 1: 1: 1, and stirred (700 r / min) for 10 minutes each to form foam slurry. 65 parts of coal gangue powder, 20 parts of self-made cementitious material, and 9 parts of mineral activator were mixed to form slurry, and 6 parts of the foam slurry was added to mix evenly, cured at 55 °C for 96 hours, demoulded and dried, crushed and screened to obtain coal-based solid waste porous sandy loam matrix material with particle size of 2~5 mm.
[0049] The obtained coal-based solid waste porous sandy loam matrix material and coal slime were mixed according to a ratio of 1:1.5, and 2% of composite microbial agent (0.5% of Bacillus mucilaginosus, 0.5% of Bacillus licheniformis, 0.5% of Bacillus megaterium, and 0.5% of Bacillus velezensis) was added, fermented for 18 days, and precipitated for 12 days to obtain the coal-based solid waste eco-restoration material. 2025201577 04 Mar 2025
[0050] Embodiment 4
[0051] The coal gangue was put into a ball mill, and a frequency of the ball mill was set at 50 Hz, and the ball milling time was 30 minutes, and the resulting sample was sieved through a 5-mesh screen.
[0052] 70 parts of fly ash, 5 parts of seed crystal, 4 parts of sodium phosphate, 15 parts of calcium oxide, and 6 parts of sodium hydroxide were weighed and mixed to form a slurry, and curing at 55 °C for 5 hours to obtain a self-made cementitious material. A mineral activator was prepared from slag, desulfurized gypsum, and carbide slag with a mass ratio of 1:2:1. Sodium dodecyl sulfate, hydroxypropyl methylcellulose, and polyvinyl alcohol were weighed and added in turn according to a mass ratio of 2: 1: 1, and stirred (700 r / min) for 10 minutes each to form foam slurry. 50 parts of coal gangue powder, 35 parts of self-made cementitious material, and 10 parts of mineral activator were mixed to form slurry, and 5 parts of foam was added to mix evenly, cured at 65 °C for 120 hours, and demoulded and dried, crushed and screened to obtain the coal-based solid waste porous sandy loam matrix material with a particle size of 2~5 mm.
[0053] The obtained coal-based solid waste porous sandy loam matrix material and coal washing by-products were mixed according to a ratio of 1:1, and 2% of composite microbial agent (1% of Bacillus licheniformis, Bacillus megaterium, and Bacillus velezensis in total; 1% of Glomus Moses and Trichoderma spp. in total) was added and fermented for 21 days, and precipitated for 14 days to obtain the coal-based solid waste eco-restoration material.
[0054] Inorganic nanogel and hydration products can be observed in the coal-based solid waste porous sandy loam matrix prepared in the above examples (FIG. 1), forming a two-dimensional network structure support system, and a measured water retention can reach 60% ~ 82%, which is up to 42% higher than a measured water retention of natural soil. A loss rate is 1.02% ~ 2.19%, which is up to 81% lower than a loss rate of soil. Coal-based solid waste eco-restoration materials were mixed with exotic soil, backfilled to an area to be restored, and alfalfa seeds were planted on it. Seeds germinated in a week, and the survival rate was 60% ~ 80%, which can meet the needs of eco-restoration. In addition, a highest addition rate of coal-based solid waste eco-restoration 2025201577 04 Mar 2025 materials can reach 80%, which is expected to realize the consumption and recycling of bulk coalbased solid waste materials.
[0055] In summary, the present disclosure provides a coal-based solid waste eco-restoration material, a preparation method and an application thereof, and the formation of the cementitious material is promoted by mixing seed crystals with fly ash and the like. Subsequently, coal gangue is used as a main raw material, mixed with cementitious materials and mineral activators, and the porous sandy loam matrix of coal-based solid waste is prepared by physical foaming technology through curing, crushing and particle size grading. In the present disclosure, the addition of the cementitious material is beneficial to strengthening the skeleton strength of sandy loam matrix, reducing the collapse of pore channels in the crushing process, and improving the water retention and air permeability of the material. Moreover, the cementitious material solidifies and coats the heavy metals in the coal gangue, which effectively reduces the content of the most mobile weak acid extracted heavy metals and transforms them into a residue state which is not easy to migrate and has weak biological toxicity. Compared with the traditional aluminum powder chemical foaming and strong acid foaming, the physical foaming technology adopted reduces the cost and improves the safety of operation, which is convenient for standardized production. Then, the sandy loam matrix is mixed with coal slime and bacterial-fungal composite microbial agent, and the coalbased solid waste eco-restoration material is prepared through fermentation and sedimentation. Through the activation of bacteria-fungi composite microbial agent, the nutrient elements in ecorestoration materials can be fully released, and at the same time, the formation of soil aggregates can be enhanced, the fertility and water retention of eco-restoration materials can be improved, which is beneficial to plant growth. At the same time, it can not cause secondary pollution to the environment and solve the problem of massive storage of coal gangue.
[0056] It should be understood that the present disclosure is not limited to the exact construction that has been described above and shown in the drawings. For those skilled in the art, modifications and transformations can be performed according to the specification. All these modifications and transformations should fall in with the protection scope of the present disclosure.
Claims
1. A method for preparing a coal-based solid waste eco-restoration material, comprising:mixing and placing calcium oleate, sodium silicate, polyvinylpyrrolidone, oleylamine, anhydrous ethanol, and water in a hydrothermal reactor, heating at a constant temperature, centrifuging, and washing to collect inorganic nano-seed crystal;seeding the inorganic nano-seed crystal to form a cementitious material; mixing coal gangue powder with the cementitious material, mineral activator, and physical pore-forming foam, then curing, crushing, and screening to prepare a porous sandy loam matrix;uniformly mixing the prepared porous sandy loam matrix, coal slime, and composite microbial agent, and then fermenting and maturing to obtain the coal-based solid waste eco-restoration material.
2. The method for preparing the coal-based solid waste eco-restoration material according to claim 1, wherein a calcium-silicon ratio of the calcium oleate to the sodium silicate is 0.6-1.6, and a hydrothermal reaction temperature is 120-180 °C for 4 hours to 12 hours.
3. The method for preparing the coal-based solid waste eco-restoration material according to claim 1, wherein the porous sandy loam matrix comprises, in parts by weight, 50-80 parts of the coal gangue powder, 10-40 parts of the cementitious material, 5-10 parts of the mineral activator, 1-8 parts of physical pore-forming foam, and a water-cement ratio is 0.5-0.7.
4. The method for preparing the coal-based solid waste eco-restoration material according to claim 1, wherein the cementitious material comprises, in parts by weight, 2-5 parts of inorganic nanoseed crystal, 50-70 parts of fly ash, 5-10 parts of sodium phosphate, 10-25 parts of calcium oxide, and 5-20 parts of sodium hydroxide.
5. The method for preparing the coal-based solid waste eco-restoration material according to claim 1, wherein the physical pore-forming foam comprises a foaming agent and a foam stabilizer, an added mass of the foam stabilizer is 20%-50%; the foaming agent is selected from one or more of sodium dodecyl sulfate, fatty alcohol polyoxyethylene ether sodium sulfate, ethoxylated alkyl2025201577 04 Mar 2025sodium sulfate, and sodium dodecyl polyoxyethylene ether succinate; the foam stabilizer is selected from hydroxypropyl methylcellulose and polyvinyl alcohol.
6. The method for preparing the coal-based solid waste eco-restoration material according to claim 1, wherein the mineral activator comprises slag, desulfurized gypsum, and carbide slag, and in parts by weight, an added ratio of each component is (2-4): (1-2): (1-2).
7. The method for preparing the coal-based solid waste eco-restoration material according to claim 1, wherein a mass ratio of the porous sandy loam matrix to the coal slime is 1: (1-2); an added amount of the composite microbial agent is 0.05%-2%, a fermenting time is 14-21 days, and a maturing time is 7-14 days.
8. The method for preparing the coal-based solid waste eco-restoration material according to claim 1, wherein the composite microbial agent comprises bacteria and fungi, and the bacteria are selected from one or more of Bacillus mucilaginosus, Bacillus licheniformis, Bacillus megaterium, Bacillus velezensis, and Acidithiobacillus ferrooxidans; the fungi comprise Arbuscular mycorrhizal fungi and Trichoderma fungi.
9. A coal-based solid waste eco-restoration material, wherein the coal-based solid waste ecorestoration material is prepared by the method for preparing the coal-based solid waste ecorestoration material according to any one of claims 1-8.
10. An application of the coal-based solid waste eco-restoration material according to claim 9, wherein the coal-based solid waste eco-restoration material is used as artificial soil for environment eco-restoration.