In-situ backfilling system for coal gangue in alkaline soil mining area

Abstract

The utility model provides an in-situ backfilling system for coal gangue in an alkaline soil mining area, and aims to solve the problem that soil remediation and leachate treatment cannot be synchronously performed during in-situ treatment of waste coal gangue in the existing alkaline soil mining area. The system comprises a soil covering area and a coal gangue stockpiling area which are arranged on the ground of the alkaline soil mining area; the soil covering area covers the coal gangue stockpiling area and is used for laying composite ecological soil for soil remediation; the coal gangue stockpiling area is used for stacking waste coal gangue in an alkaline earth mining area and comprises a percolation tank, a grating is arranged at the top of the percolation tank, and impermeable layers are laid on the tank bottom and the tank wall of the percolation tank; and the percolation tank is used for placing a repairing agent for treating heavy metal percolate in the waste coal gangue in the mining area in the tank body. The composite ecological soil is laid in the soil covering area to achieve soil remediation, the percolation tank capable of containing the remediation agent is arranged in the coal gangue stockpiling area, in-situ treatment can be synchronously conducted on percolate generated by coal gangue leaching, harmless treatment is achieved, and the device has great application prospects.

Description

Technical Field

[0001] The utility model relates to the technical field of coal gangue solid waste disposal, in particular to an alkaline earth mining area coal gangue on-site backfilling system. Background Art

[0002] Northwest my country is an important energy base in China, with rich and widely distributed coal resources. Coal gangue is solid waste generated and discharged during coal mining and washing and processing, and its discharge accounts for about 10-20% of raw coal production. At present, the treatment of coal gangue is mainly open-air stacking or discharge along the ditch. The coal gangue mine pile not only occupies a large amount of land, but also the heavy metal leachate in the coal gangue can easily cause ecological and environmental problems such as groundwater system damage, mining area ground collapse, and mining area water and soil pollution. Therefore, it is urgent to solve the problems of coal gangue storage and efficient comprehensive utilization of coal gangue.

[0003] The common way to deal with coal gangue storage is to adopt harmless disposal, which mainly includes ground backfill and underground backfill; among them, ground backfill includes foundation and road filling, land reclamation, etc.; underground backfill mainly includes solid backfill, paste (similar to paste) backfill and grouting backfill. However, the above methods cannot simultaneously carry out soil remediation and leachate treatment.

[0004] Therefore, it is of great significance to study a method that can simultaneously perform soil remediation and treat coal gangue leachate. Utility Model Content

[0005] The utility model aims to solve the problem that the prior art cannot simultaneously carry out soil repair and leachate treatment in the in-situ backfill technology of coal gangue. A covering soil area and a coal gangue storage area are arranged on the bottom surface of the alkaline earth mining area, and composite ecological soil is laid in the covering soil area. The bacterial agent and slow-release carbon source in the ecological soil can simultaneously produce acid to neutralize the alkalinity in the alkaline earth, thereby realizing soil repair. A percolation trough for placing a repair agent is arranged in the coal gangue storage area, and the leachate generated by the leaching of the coal gangue can be simultaneously treated in situ to realize the harmless disposal of the coal gangue.

[0006] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0007] A coal gangue in-situ backfill system for alkaline earth mining areas comprises: a covering area and a coal gangue storage area arranged on the ground of the alkaline earth mining area; the covering area covers the top of the coal gangue storage area and is used for laying composite ecological soil for soil restoration, which provides conditions for plant growth and ecological restoration while absorbing the coal gangue; the coal gangue storage area is used for stacking coal gangue discarded in the alkaline earth mining area, and comprises a percolation trough, a grid is arranged on the top of the percolation trough, and an anti-seepage layer is laid on the bottom and the trough wall of the percolation trough; the trough body of the percolation trough is used for placing a repair agent for treating heavy metal leachate in the discarded coal gangue in the mining area.

[0008] As the preferred technical solution:

[0009] Optionally, there are a plurality of infiltration tanks, which are evenly arranged in the gangue storage area.

[0010] Optionally, the infiltration tank is located on the surface of the ground in the alkaline earth mining area, and the coal gangue is piled on the ground in the coal gangue storage area.

[0011] Optionally, the infiltration tank is located in a depression on the ground of the alkaline earth mining area, and the gangue is located in the gangue storage area in a landfill manner.

[0012] Optionally, the gangue storage area is also provided with an observation well, which is perpendicular to the covering area and passes from the ground to one side of the infiltration tank, and can be used for inspection and maintenance, and can also be used as a feeding port for the repair agent.

[0013] Optionally, the structure of the grille is an aluminum alloy plate with holes.

[0014] Optionally, the anti-seepage layer is a bentonite composite waterproof blanket. The provision of the anti-seepage layer can prevent the leachate that has not reacted with the repair agent from flowing to the underground and polluting the soil.

[0015] Optionally, the thickness of the soil covering area is 40-90 cm. The thickness of the soil covering area of ​​the utility model depends on the type of vegetation to be planted and the thickness of the soil suitable for growth is selected.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] The utility model discloses an in-situ backfilling system for gangue in alkaline earth mining areas, wherein composite ecological soil is laid in the covering soil area, wherein the bacterial agent and slow-release carbon source in the ecological soil can simultaneously produce acid to neutralize the alkalinity in the alkaline earth, thereby realizing soil repair; a percolation tank for placing a repair agent is arranged in the gangue storage area, wherein the percolation liquid generated by the leaching of the gangue can be simultaneously treated in situ, thereby realizing harmless disposal of the gangue. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a schematic diagram of the structure of the utility model of the on-site backfill system for coal gangue in alkaline earth mining areas;

[0020] Figure 2This is a system cross-section diagram of the utility model of coal gangue in alkaline earth mining area in the form of ground storage;

[0021] Figure 3 This is a system cross-section diagram of the utility model of coal gangue landfill in alkaline earth mining area;

[0022] Reference numerals:

[0023] 1-composite ecological soil; 2-observation well; 3-infiltration trough; 4-repairing agent; 5-grid; 6-abandoned coal gangue; 7-crushed coal gangue; 8-slow-release carbon source; 9-humic acid; 10-ecological restoration bacterial agent; 11-sulfate-reducing bacteria carrier; 12-sulfate-reducing bacteria; 13-anti-seepage layer. DETAILED DESCRIPTION

[0024] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the products of the present invention are conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0029] The disclosure below provides many different embodiments or examples for realizing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the utility model. In addition, the utility model may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the utility model provides various specific examples of processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

[0030] The embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0031] The utility model provides a system for backfilling coal gangue in situ in alkaline earth mining areas. Figures 1 to 3As shown, it includes: a covering area and a gangue storage area arranged on the ground of the alkaline earth mining area; the covering area covers the top of the gangue storage area and is used to lay the composite ecological soil 1 for soil restoration, which provides conditions for plant growth and ecological restoration while absorbing the gangue; the gangue storage area is used to stack the abandoned gangue 6 in the alkaline earth mining area, which includes a percolation trough 3, a grille 5 is arranged on the top of the percolation trough, and an anti-seepage layer 13 is laid on the bottom and the wall of the percolation trough 3; the trough body of the percolation trough is used to place a repair agent 4 for treating the heavy metal leachate in the abandoned gangue in the mining area, wherein the structure of the grille 5 is an aluminum alloy plate with holes, and the anti-seepage layer 13 is a bentonite composite waterproof blanket, and the thickness of the covering area (i.e., the thickness of the composite ecological soil laid) is 40~90cm.

[0032] The infiltration tank 3 may be a large tank body (not shown in the figure), or may be divided into several tank bodies evenly arranged in the coal gangue storage area.

[0033] In the embodiment of the utility model, there are two ways to set the infiltration tank. One way is that the infiltration tank is located on the surface of the ground in the alkaline earth mining area, and the coal gangue is piled on the ground in the coal gangue storage area. Figure 2 shown.

[0034] Another method is to locate the infiltration tank in the depression of the ground in the alkaline earth mining area, and the coal gangue is landfilled in the coal gangue storage area, such as Figure 3 As shown, when the coal gangue is landfilled in the coal gangue storage area, an observation well 2 is set in the storage area, which is perpendicular to the covering area and passes from the ground to one side of the infiltration tank. It can be used for inspection and maintenance, and can also be used as a feeding port for the repair agent.

[0035] The utility model lays composite ecological soil for soil repair in a covering soil area. The composite ecological soil is a composite repair material composed of local alkaline soil, crushed coal gangue 7, a slow-release carbon source 8, humic acid 9 and a soil repair bacterial agent 10. The humic acid is potassium humate, the slow-release carbon source is obtained by crushing local discarded straw, rice straw, cow dung, sawdust, bark or pine needles, and the soil repair bacterial agent is composed of Bacillus subtilis, Brevibacillus laterosporus and Bacillus megaterium.

[0036] The utility model places a repair agent 4 for treating heavy metal leachate in abandoned coal gangue in the mining area in the trough body of the infiltration trough. The selected repair agent 4 is composed of a sulfate-reducing bacteria carrier 11 and sulfate-reducing bacteria 12. The repair agent solidifies sulfate and heavy metals in the coal gangue leachate, realizes in-situ treatment of the leachate and can be reused. The coal gangue in-situ backfilling system of the alkaline earth mining area of ​​the utility model effectively overcomes the shortcomings of traditional technologies, improves the ecological quality of the mining area, and is a passive treatment system that does not occupy ground space and does not require external power.

Claims

1. An on-site backfill system for coal gangue in alkaline earth mining areas, characterized in that: include: A covering soil area and a gangue storage area are arranged on the ground of an alkaline earth mining area; the covering soil area covers the gangue storage area and is used for laying composite ecological soil for soil restoration; The gangue storage area is used for stacking abandoned gangue from alkaline earth mining areas, and includes a percolation trough, a grid is arranged on the top of the percolation trough, and an anti-seepage layer is laid on the bottom and the wall of the percolation trough; the trough body of the percolation trough is used for placing a repair agent for treating heavy metal leachate in the abandoned gangue in the mining area.

2. The in-situ backfill system for coal gangue in alkaline earth mining areas according to claim 1 is characterized by: There are a number of infiltration tanks which are evenly arranged in the gangue storage area.

3. The in-situ backfill system for coal gangue in alkaline earth mining areas according to claim 2 is characterized by: The infiltration tank is located on the surface of the ground in the alkaline earth mining area, and the coal gangue is piled on the ground and is located in the coal gangue storage area.

4. The on-site backfill system for coal gangue in alkaline earth mining areas according to claim 2 is characterized by: The infiltration tank is located in a depression on the ground of the alkaline earth mining area, and the coal gangue is located in the coal gangue storage area in a landfill manner.

5. The on-site backfill system for coal gangue in alkaline earth mining areas according to claim 4 is characterized by: The gangue storage area is also provided with an observation well, which is perpendicular to the covering area and penetrates from the ground to one side of the infiltration tank.

6. The on-site backfill system for coal gangue in alkaline earth mining areas according to claim 1 is characterized by: The structure of the grille is an aluminum alloy plate with holes.

7. The in-situ backfill system for coal gangue in alkaline earth mining areas according to claim 1, characterized in that: The anti-seepage layer is a bentonite composite waterproof blanket.

8. The in-situ backfill system for coal gangue in alkaline earth mining areas according to claim 1, characterized in that: The thickness of the soil covering area is 40-90 cm.

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