Coal-based solid waste ecological restoration material and preparation method thereof

Abstract

The invention discloses a coal-based solid waste ecological restoration material and a preparation method thereof. The preparation method comprises the following steps: mixing coal gangue powder with a cementing material, a mineral activator and a physical pore-forming foam body, and curing to prepare a porous sandy soil matrix; and uniformly mixing the prepared porous sandy soil matrix with coal slime and a complex microbial inoculant, and performing fermentation and precipitation to obtain the coal-based solid waste ecological restoration material. Due to the addition of the cementing material, the strength of a sandy soil matrix framework is enhanced, collapse of pore channels in the crushing process is reduced, and the water retention and air permeability of the material are improved. Compared with traditional aluminum powder chemical foaming and strong acid foaming, the physical foaming technology adopted by the invention improves the operation safety while reducing the cost, and facilitates standardized production. Nutrient elements in the ecological restoration material can be fully released through the activation effect of the bacterium-fungus complex microbial inoculant. The ecological restoration material can be applied to environmental restoration fields such as mine soil restoration and land reclamation.

Description

Technical Field

[0001] The present invention relates to the technical field of gangue resource utilization, and in particular to a coal-based solid waste ecological restoration material and a preparation method thereof. Background Art

[0002] With the continuous development of coal mining and washing industry, the large-scale generation of coal-based solid waste, especially gangue, coal slime and fly ash, has become one of the biggest environmental and resource challenges in my country. Gangue, as a by-product of coal mining, accounts for 10-15% of the raw coal output, and the current stockpile has exceeded 7 billion tons. The long-term random stacking of gangue not only encroaches on land resources and damages the ecological environment, but also brings serious air, water and soil pollution, and even causes geological disasters, endangering human safety. Similarly, due to its high water content and complex composition, coal slime is prone to sedimentation and water pollution after stacking, while fly ash, as the main by-product of coal-fired power plants, has an annual emission of up to 790 million tons. The ecological and environmental pressure brought by the stockpile cannot be ignored.

[0003] Coal-based solid waste is not only complex in composition, but also has the potential risk of heavy metal pollution. However, these wastes contain components similar to soil and have great potential in ecological restoration and soil improvement in mining areas. The national level actively advocates the comprehensive utilization of solid waste resources and promotes its application in ecological restoration. The patent "An activated coal gangue-based compressed ecological soil and its preparation method" (CN 118303294 A) improves the fertility and weather resistance of coal gangue by adding compost, organic water-retaining materials, etc., and improves the soil structure to make it a more ecologically adaptable compressed ecological soil. The patent "A coal gangue soil improvement structure" (CN219719044 U) proposes a solution to improve saline-alkali soil through a multi-layer structure, and lays coal gangue powder layer, microbial layer, straw layer and plant ash layer on the soil layer in sequence. This structure effectively reduces the cost of soil improvement, while enhancing the rooting ability of vegetation and improving the ability to resist wind and sand. However, existing utilization technologies have many shortcomings. For example, simply mixing coal gangue and raw soil easily results in large 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 prior art needs to be further improved and enhanced. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the present invention provides a coal-based solid waste ecological restoration material and a preparation method thereof, aiming to solve the problem that the existing coal-based solid waste ecological restoration materials are difficult to industrialize due to the need to use a chemical foaming method during the preparation process, easy collapse of porous materials, poor water retention and heavy metal pollution.

[0006] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0007] In a first aspect, a method for preparing a coal-based solid waste ecological restoration material comprises:

[0008] Calcium oleate, sodium silicate, polyvinyl pyrrolidone, oleylamine, anhydrous ethanol and water are mixed and placed in a hydrothermal reactor, and the inorganic nanocrystal seeds are collected by constant temperature heating reaction, centrifugation and washing;

[0009] The inorganic nano-crystal seeds are sown to form a gelling material; coal gangue powder is mixed with the gelling material, a mineral activator and a physical pore-forming foam, and after curing, a porous sandy soil matrix is ​​prepared by crushing and screening;

[0010] The prepared porous sandy soil matrix is ​​evenly mixed with coal slime and composite bacterial agent, and the coal-based solid waste ecological restoration material is obtained through fermentation and sedimentation.

[0011] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0012] As a preferred technical solution, the method for preparing the coal-based solid waste ecological restoration material is described, wherein the calcium-silicon ratio of the calcium oleate and the sodium silicate is 0.6-1.6, the temperature of the hydrothermal reaction is 120-180°C, and the time is 4-12 hours.

[0013] As a preferred technical solution, the method for preparing the coal-based solid waste ecological restoration material, wherein, in terms of weight parts, the porous sandy loam matrix contains: 50 to 80 parts of coal gangue powder, 10 to 40 parts of cementitious material, 5 to 10 parts of mineral activator, 1 to 8 parts of physical pore-forming foam, and a water-cement ratio of 0.5 to 0.7.

[0014] As a preferred technical solution, the method for preparing the coal-based solid waste ecological restoration material, wherein, in terms of weight, the cementitious material comprises: 2 to 5 parts of inorganic nanocrystal seeds, 50 to 70 parts of fly ash, 5 to 10 parts of sodium phosphate, 10 to 25 parts of calcium oxide, and 5 to 20 parts of sodium hydroxide.

[0015] As a preferred technical solution, the preparation method of the coal-based solid waste ecological restoration material, wherein the physical pore-forming foam contains a foaming agent and a foam stabilizer, wherein the added mass ratio of the foam stabilizer is 20-50%; the foaming agent is selected from one or more of sodium lauryl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium ethoxylated alkyl sulfate and sodium lauryl polyoxyethylene ether succinic acid ester. The foam stabilizer is selected from hydroxypropyl methylcellulose and polyvinyl alcohol.

[0016] As a preferred technical solution, in the method for preparing the coal-based solid waste ecological restoration material, the mineral activator comprises: slag, desulfurized gypsum, and carbide slag. In terms of weight, the addition ratio of each component is: (2-4): (1-2): (1-2).

[0017] As a preferred technical solution, the method for preparing the coal-based solid waste ecological restoration material is described, wherein the mass ratio of the porous sandy loam matrix to the coal slime is 1:(1-2); the amount of the composite bacterial agent added is 0.05%-2%, the fermentation time is 14-21 days, and the sedimentation time is 7-14 days.

[0018] As a preferred technical solution, the method for preparing the coal-based solid waste ecological restoration material is characterized in that the composite bacterial agent is composed of bacteria and fungi, the bacteria are selected from one or more of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium, Bacillus velez and Bacillus ferrooxidans; the fungi are arbuscular mycorrhizal fungi and Trichoderma.

[0019] In a second aspect, a coal-based solid waste ecological restoration material is provided, wherein the coal-based solid waste ecological restoration material is prepared using the preparation method described above.

[0020] In a third aspect, the above-mentioned coal-based solid waste ecological restoration material is used as artificial soil for ecological restoration of the environment.

[0021] Beneficial effects: Compared with the prior art, the present invention uses coal gangue as the main raw material, mixes it with a cementing material and a mineral activator, and uses physical foaming technology to prepare a coal-based solid waste porous sandy loam matrix through curing, crushing, and particle size grading. In the present invention, the inorganic nanocrystal seeds developed by the self-developed method can accelerate the process of hydration reaction and accelerate the formation of cementing materials through nucleation seeding. With the addition of cementing materials, it is beneficial to enhance the skeleton strength of the sandy loam matrix, reduce the collapse of the pores during the crushing process, and improve the water retention and air permeability of the material; and the cementing material solidifies the heavy metals in the coal gangue, effectively reducing the content of the most fluid weak acid extraction state of heavy metals, and converting it into a residue state that is not easy to migrate and has weak biological toxicity. Compared with traditional aluminum powder chemical foaming and strong acid foaming, the physical foaming technology used in the present invention reduces costs while improving the safety of operation, and is convenient for standardized production. Then, the sandy loam matrix is ​​mixed with coal slime and composite bacterial agent, and the coal-based solid waste ecological restoration material is obtained through fermentation and sedimentation. The nutrient elements in the ecological restoration material can be fully released through the activation of the composite bacterial agent to improve fertility. On the one hand, it changes the form and effectiveness of heavy metals in the soil by secreting chelating substances and redox reactions, and cooperates with sandy loam matrix to synergistically reduce heavy metal pollution. On the other hand, the composite bacterial agent can promote the formation of soil aggregates, which is also beneficial to improve the water retention and air permeability of the soil, which is beneficial to plant growth. At the same time, it will not cause secondary pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the process for preparing the coal-based solid waste ecological restoration material provided by the present invention;

[0023] Figure 2 A network structure support system is formed for inorganic nanogels and hydration products in the porous sandy soil matrix of coal-based solid waste;

[0024] Figure 3 XRD patterns of inorganic nanocrystal seeds synthesized under different conditions in porous sandy soil matrix of coal-based solid waste;

[0025] Figure 4 FT IR images of inorganic nanocrystal seeds synthesized under different conditions in coal-based solid waste porous sandy loam matrix, proving that the CSH synthesis of inorganic nanocrystal seeds promotes the hydration rate and strength development of gel materials. DETAILED DESCRIPTION

[0026] The present invention provides a coal-based solid waste ecological restoration material and a preparation method and application thereof. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] It will be understood by those skilled in the art that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present application refers to the presence of the 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" used herein includes all or any unit and all combinations of one or more associated listed items.

[0028] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art to which this application 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 will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0029] It should be understood that the sequence number and size of each step in this embodiment do not mean the order of execution, and the execution order of each process is determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of this application. All instruments used are commercially available products.

[0030] like Figure 1 As shown, the method for preparing the coal-based solid waste ecological restoration material provided by the present invention comprises:

[0031] Step S10, calcium oleate, sodium silicate, polyvinyl pyrrolidone, oleylamine, anhydrous ethanol, and water are mixed and placed in a hydrothermal reactor, and the inorganic nanocrystals are collected by constant temperature heating, centrifugation, washing, and reaction.

[0032] In this step, the seed crystal is prepared by a two-phase interface method. Figure 2 There are a large number of broken bonds and structural defects on the surface of the seed crystal, which can serve as new nucleation sites, greatly reducing the nucleation barrier and promoting the formation of gelling materials.

[0033] Step S20, the inorganic nano-crystal seeds are sown to form a gelling material; the coal gangue powder is mixed with the gelling material, the mineral activator, and the physical pore-forming foam, and the porous sandy soil matrix is ​​prepared by curing.

[0034] In this embodiment, the addition of cementitious materials is beneficial to enhance the skeleton strength of the sandy loam matrix, reduce the collapse of the pores during the crushing process, and improve the water retention and air permeability of the material; and the cementitious materials solidify and coat the heavy metals in the coal gangue, effectively reducing the content of the most fluid weak acid extraction state of heavy metals and converting them into a residue state that is not easy to migrate and has weak biological toxicity. Compared with traditional aluminum powder chemical foaming and strong acid foaming, the physical foaming technology used in this embodiment reduces costs while improving the safety of operation and facilitates standardized production.

[0035] Step S30, uniformly mixing the prepared porous sandy loam matrix with coal slime and composite bacterial agent, and obtaining coal-based solid waste ecological restoration materials through fermentation and sedimentation.

[0036] In this embodiment, the nutrient elements in the ecological restoration material can be fully released through the activation of the composite bacterial agent, and at the same time, the formation of soil aggregates is enhanced, the fertility and water retention of the ecological restoration material are improved, and the growth of plants is beneficial. The ecological restoration material can be applied to the fields of mine soil restoration, land reclamation, etc.

[0037] The above technical solution provided by the present invention is further explained below through a specific preparation method.

[0038] Example 1

[0039] Put the coal gangue into the ball mill, set the frequency of the ball mill to 40 Hz, the ball milling time to 30 min, and the prepared sample is passed through 10 mesh.

[0040] Weigh 60 parts of fly ash, 3 parts of seed crystals, 10 parts of sodium phosphate, 12 parts of calcium oxide and 15 parts of sodium hydroxide, add water to make a slurry, and cure for 3 hours at a temperature of 35°C to obtain the self-made cementitious material. The mineral activator is configured with slag, desulfurized gypsum and carbide slag in a mass ratio of 2:1:2. Weigh sodium dodecyl sulfate and hydroxypropyl methylcellulose and add them in sequence in a mass ratio of 1:1 and stir (600r / min) for 15 minutes each to form a foam slurry. Weigh 60 parts of coal gangue powder, 25 parts of self-made cementitious material, 8 parts of mineral activator, and then add 7 parts of foam slurry to mix evenly. At a temperature of 35°C, cure for 72 hours, and after demolding and drying, crush and screen to obtain a coal-based solid waste porous sandy soil matrix material with a particle size of less than 5 mm.

[0041] The obtained coal-based solid waste porous sandy soil matrix material and coal slime were mixed in a ratio of 1:1, and 0.5% composite bacterial agent was added. The composite bacterial agent was composed of Bacillus subtilis, Bacillus velez and Trichoderma harzianum, and the addition ratio was 1:1:1. The mixture was fermented for 14 days and settled for 7 days to obtain the coal-based solid waste ecological restoration material.

[0042] Example 2

[0043] Put the coal gangue into the ball mill, set the frequency of the ball mill to 50 Hz, the ball milling time to 60 min, and the prepared sample passed through 18 mesh.

[0044] Weigh 56 parts of fly ash, 4 parts of seed crystals, 10 parts of sodium phosphate, 10 parts of calcium oxide and 20 parts of sodium hydroxide, add water to make a slurry, and cure for 3 hours at a temperature of 40°C to obtain the self-made cementitious material. Weigh slag, desulfurized gypsum, and carbide slag and prepare the mineral activator according to a mass ratio of 3:2:1. Weigh sodium dodecyl sulfate, sodium dodecyl polyoxyethylene ether succinate sulfonate and hydroxypropyl methylcellulose in a mass ratio of 2:1:1 and add and stir (600r / min) for 10 minutes each to form a foam slurry. Weigh 56 parts of coal gangue powder, 30 parts of self-made cementitious material, and 6 parts of mineral activator, and then add 8 parts of foam slurry to mix evenly. At a temperature of 60°C, cure for 48 hours, and after demolding and drying, crush and screen to obtain a coal-based solid waste porous sandy soil matrix material with a particle size of less than 5mm.

[0045] The obtained coal-based solid waste porous sandy loam matrix material and coal washing by-products were mixed in a ratio of 1:1.5, and 1.5% composite bacterial agent (1% of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium, and 0.5% of Trichoderma harzianum) was added for fermentation for 16 days and sedimentation for 9 days to obtain coal-based solid waste ecological restoration materials.

[0046] Example 3

[0047] Put the coal gangue into the ball mill, set the frequency of the ball mill to 50 Hz, the ball milling time to 90 min, and the prepared sample is passed through 30 mesh.

[0048] Weigh 50 parts of fly ash, 5 parts of seed crystals, 10 parts of sodium phosphate, 24 parts of calcium oxide, and 11 parts of sodium hydroxide to make a slurry, and cure for 5 hours at a temperature of 50°C to obtain the self-made cementitious material. Weigh slag, desulfurized gypsum, and carbide slag and prepare the mineral activator according to a mass ratio of 2:2:1. Weigh sodium dodecyl sulfate, hydroxypropyl methylcellulose, and polyvinyl alcohol, and add them in sequence according to a mass ratio of 1:1:1 and stir (700r / min) for 10 minutes each to form a foam slurry. Weigh 65 parts of coal gangue powder, 20 parts of self-made cementitious material, 9 parts of mineral activator to make a slurry, add 6 parts of foam slurry and mix evenly, cure for 96 hours at a temperature of 55°C, and crush and screen after drying to obtain a coal-based solid waste porous sandy soil matrix material with a particle size of 2 to 5 mm.

[0049] The obtained coal-based solid waste porous sandy loam matrix material and coal slime were mixed in a ratio of 1:1.5, and 2% composite bacterial agent (0.5% each of Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium and Bacillus velezii) was added for fermentation for 18 days and sedimentation for 12 days to obtain coal-based solid waste ecological restoration materials.

[0050] Example 4

[0051] Put the coal gangue into the ball mill, set the frequency of the ball mill to 50 Hz, the ball milling time to 30 min, and the prepared sample is passed through 5 mesh.

[0052] Weigh 70 parts of fly ash, 5 parts of seed crystals, 4 parts of sodium phosphate, 15 parts of calcium oxide and 6 parts of sodium hydroxide to make a slurry, and cure for 5 hours at a temperature of 55°C to obtain the self-made cementitious material. Weigh slag, desulfurized gypsum, and carbide slag and prepare the mineral activator according to a mass ratio of 1:2:1. Weigh sodium dodecyl sulfate, hydroxypropyl methylcellulose and polyvinyl alcohol, and add them in sequence according to a mass ratio of 2:1:1 and stir (700r / min) for 10 minutes each to form a foam slurry. Weigh 50 parts of coal gangue powder, 35 parts of self-made cementitious material, 10 parts of mineral activator to make a slurry and add 5 parts of foam to mix evenly, and cure for 120 hours at a temperature of 65°C. The dried solid is crushed and sieved to obtain a coal-based solid waste porous sandy soil matrix material with a particle size of 2 to 5 mm.

[0053] The obtained coal-based solid waste porous sandy loam matrix material and coal slime were mixed in a ratio of 1:1, and 2% composite bacterial agent (1% of Bacillus licheniformis, Bacillus megaterium and Bacillus velezii, 1% of Glomus mosseae and Trichoderma) was added for fermentation for 21 days and sedimentation for 14 days to obtain coal-based solid waste ecological restoration materials.

[0054] Inorganic nanogels and hydration products ( Figure 1 ), forming a two-dimensional network structure support system, the measured water retention can reach 60-82%, an increase of 42% over natural soil; the loss rate is 1.02-2.19%, a maximum decrease of 81% over soil. The coal-based solid waste ecological restoration materials and foreign soil are mixed, backfilled into the area to be restored, and alfalfa seeds are planted on it. The seeds begin to germinate in a week, with a survival rate of 60% to 80%, which can meet the needs of ecological restoration. Among them, the maximum addition rate of coal-based solid waste ecological restoration materials can reach 80%, which is expected to achieve the disposal and recycling of large quantities of coal-based solid waste materials.

[0055] In summary, the present invention provides a coal-based solid waste ecological restoration material and a preparation method and application thereof, and promotes the formation of a cementitious material by mixing a seed with fly ash and the like. Subsequently, coal gangue is used as the main raw material, mixed with a cementitious material and a mineral activator, and a coal-based solid waste porous sandy loam matrix is ​​prepared by curing, crushing, and particle size grading using a physical foaming technology. In the present invention, the addition of a cementitious material is beneficial to enhancing the skeleton strength of the sandy loam matrix, reducing the collapse of the pores during the crushing process, and improving the water retention and air permeability of the material; and the cementitious material solidifies and coats the heavy metals in the coal gangue, effectively reducing the most fluid weak acid extraction state of heavy metals, and converting them into a residue state that is not easy to migrate and has weak biological toxicity. Compared with traditional aluminum powder chemical foaming and strong acid foaming, the physical foaming technology used reduces costs while improving the safety of operation, and is convenient for standardized production. Next, the sandy loam matrix is ​​mixed with coal slime and a bacterial-fungal composite inoculant, and the coal-based solid waste ecological restoration material is obtained by fermentation and precipitation. The activation of bacterial-fungal composite agents can fully release the nutrients in ecological restoration materials, while enhancing the formation of soil aggregates, improving the fertility and water retention of ecological restoration materials, and facilitating plant growth. At the same time, it will not cause secondary pollution to the environment and solve the problem of large-scale storage of coal gangue.

[0056] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for preparing a coal-based solid waste ecological restoration material, characterized in that: include: Calcium oleate, sodium silicate, polyvinyl pyrrolidone, oleylamine, anhydrous ethanol and water are mixed and placed in a hydrothermal reactor, and the inorganic nanocrystal seeds are collected by constant temperature heating reaction, centrifugation and washing; The inorganic nano-crystal seeds are sown to form a gelling material; coal gangue powder is mixed with the gelling material, a mineral activator and a physical pore-forming foam, and after curing, a porous sandy soil matrix is ​​prepared by crushing and screening; The prepared porous sandy soil matrix is ​​evenly mixed with coal slime and composite bacterial agent, and the coal-based solid waste ecological restoration material is obtained through fermentation and sedimentation.

2. The method for preparing the coal-based solid waste ecological restoration material according to claim 1, characterized in that: The calcium-silicon ratio of the calcium oleate and the sodium silicate is 0.6-1.6, the temperature of the hydrothermal reaction is 120-180° C., and the time is 4-12 hours.

3. The method for preparing the coal-based solid waste ecological restoration material according to claim 1, characterized in that: In terms of weight, the porous sandy soil matrix comprises: 50 to 80 parts of coal gangue powder, 10 to 40 parts of cementitious materials, 5 to 10 parts of mineral activators, 1 to 8 parts of physical pore-forming foams, and a water-cement ratio of 0.5 to 0.

7.

4. The method for preparing the coal-based solid waste ecological restoration material according to claim 1, characterized in that: In terms of weight, the gelling material comprises: 2 to 5 parts of inorganic nano-crystal seeds, 50 to 70 parts of fly ash, 5 to 10 parts of sodium phosphate, 10 to 25 parts of calcium oxide, and 5 to 20 parts of sodium hydroxide.

5. The method for preparing the coal-based solid waste ecological restoration material according to claim 1, characterized in that: The physical pore-forming foam comprises a foaming agent and a foam stabilizer, wherein the foam stabilizer is added in an amount of 20 to 50% by weight; the foaming agent is selected from one or more of sodium lauryl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium ethoxylated alkyl sulfate and sodium lauryl polyoxyethylene ether succinic acid ester. The foam stabilizer is selected from hydroxypropyl methylcellulose and polyvinyl alcohol.

6. The method for preparing the coal-based solid waste ecological restoration material according to claim 1, characterized in that: The mineral activator comprises: slag, desulfurized gypsum, and carbide slag. Calculated by weight, the addition ratio of each component is: (2-4): (1-2): (1-2).

7. The method for preparing the coal-based solid waste ecological restoration material according to claim 1, characterized in that: The mass ratio of the porous sandy soil matrix to the coal slime is 1:(1-2); the addition amount of the composite bacterial agent is 0.05%-2%, the fermentation time is 14-21 days, and the sedimentation time is 7-14 days.

8. The method for preparing the coal-based solid waste ecological restoration material according to claim 1, characterized in that: The composite bacterial agent is composed of bacteria and fungi, wherein the bacteria are selected from one or more of Bacillus colloids, Bacillus licheniformis, Bacillus megaterium, Bacillus velez and Bacillus ferrooxidans; and the fungi are arbuscular mycorrhizal fungi and Trichoderma.

9. A coal-based solid waste ecological restoration material, characterized in that: The coal-based solid waste ecological restoration material is prepared by the preparation method described in any one of claims 1-8.

10. The coal-based solid waste ecological restoration material according to claim 9, used as artificial soil for ecological restoration of the environment.

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