Method for repairing ecology of geological disaster area of mining area by using coal gangue

Abstract

The invention provides a method for repairing ecology of a geological disaster area of a mining area by using coal gangue, and relates to the field of repairing mining areas by using coal gangue. The restoration method for restoring the ecology of the geological disaster area of the mining area through the coal gangue comprises the following specific restoration steps that 1, the disaster collapse area is cleaned and constructed, specifically, loose broken stones and dangerous rocks in the collapse area are removed, and a slope surface is trimmed to enhance the adhesive force of a filling body; 2, coal gangue repairing is conducted, specifically, for a bottom layer foundation, II-type coal gangue with the particle size being 30-100 mm is mixed with cement and soil according to the proportion of 3: 3: 2, and lime accounting for 3%-5% of the total weight of the mixture and fly ash accounting for 10%-15% of the total weight of the mixture are added; reinforcing the middle layer: mixing the coal gangue blocks with cement to form a composite body with higher compressive strength, and discharging bubbles in the coal gangue blocks mixed with the cement through a vibrating bar. The mixture has prominent environmental benefits, a large amount of coal gangue and coal ash can be utilized, solid waste accumulation is reduced, and meanwhile, the lime can solidify heavy metal and reduce pollution risks.

Description

Technical Field

[0001] The present invention relates to the technical field of coal gangue restoration of mining areas, in particular to a restoration method for restoring the ecology of geological disaster areas in mining areas by using coal gangue. Background Art

[0002] Mine geological disasters, also known as mine geological disasters and mining geological disasters, refer to disasters that endanger human life and property safety, damage mining engineering equipment and mining resources and environment, and affect mining production due to the destruction of large-scale mining shafts and tunnels, deformation of rock and soil, and serious changes in the geological, hydrogeological conditions and natural environment of the mining area during mineral deposit mining activities.

[0003] The repair methods for geological disaster areas in mining areas in the existing technology are to remove dangerous rock masses and potentially unstable blocks, cut slopes, implement systematic anchoring and retaining wall support, use steel mesh sprayed concrete support for broken zones, establish a combined surface and underground drainage system, and drill water holes for drainage when necessary; this repair method uses existing reinforced concrete, and the coal gangue in the mining area is solid waste generated during coal mining and washing, so it is necessary to utilize and fill this waste to improve resource recycling.

[0004] When applying for the present invention, the applicant searched and found that a Chinese patent disclosed a "method for repairing the ecology of geological disaster areas in mining areas using coal gangue", and its application number is "202010689998.6". This patent mainly solves the problem that when coal gangue is unloaded by a dump truck, the impact force of coal gangue is large, which will cause a certain degree of damage to the roadbed, and the coal gangue cannot be fully unloaded on the roadbed. The later leveling of the coal gangue is relatively cumbersome. However, this patent is for repairing the roadbed in the mining area. At the same time, the slope in the mining area is large. When rainwater erosion occurs, landslides and collapse risks will occur. The geological disasters after the collapse also need to be further repaired to improve the safety of use. Therefore, according to the applicant's invention, a method for repairing the ecology of geological disaster areas in mining areas using coal gangue was invented, which solves the problem that landslides and collapse risks will occur when rainwater erosion occurs. The geological disasters after the collapse also need to be further repaired to prevent dangers during use. Summary of the Invention

[0005] (1) Technical problems solved

[0006] In response to the shortcomings of the existing technology, the present invention provides a method for repairing the ecology of geological disaster areas in mining areas using coal gangue, which solves the risk of landslides and collapses caused by rainwater erosion. The geological disasters after the collapse also need further repair to prevent dangerous problems during use.

[0007] (2) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: a method for repairing the ecology of a geological disaster area in a mining area using coal gangue, comprising the following specific repair steps:

[0009] Step 1: Cleaning and constructing the collapsed area: remove loose gravel and dangerous rocks in the collapsed area, and trim the slope to enhance the adhesion of the filling;

[0010] Step 2: Gangue repair:

[0011] Bottom foundation: Use Class II coal gangue with a particle size of 30-100mm mixed with cement and soil in a ratio of 3:3:2, and add 3%-5% of lime and 10%-15% of fly ash based on the total weight of the mixture;

[0012] Middle layer reinforcement: After the coal gangue blocks are mixed with cement, they can form a composite with high compressive strength. The bubbles in the coal gangue blocks after mixing with cement are discharged through a vibrating rod, and the density sensor detects the slurry density in real time.

[0013] Surface restoration: Cover with a mixture of coal gangue particles ≤30mm, organic fertilizer, and water-retaining agent to provide a substrate for subsequent vegetation planting;

[0014] Step 3: Waterproof protection: Lay a geomembrane or asphalt waterproof layer between the middle layer and the surface layer to prevent the leakage of harmful substances from coal gangue and pollute the surrounding environment;

[0015] Step 4: Slope solidification: Use steel mesh to anchor the filler or spray concrete to further improve the scour resistance;

[0016] Step 5: Geological restoration: After the restoration is completed, drought-resistant shrub seeds and seedlings can be spread on the surface to use the root system to consolidate the slope and gradually restore the ecological function.

[0017] Preferably, in step 2: the bottom layer reinforcement enhances the hydration reaction activity between the gangue surface and cement through chemical excitation, thereby enhancing the interfacial bonding force of the gangue, and forms an anti-skid base layer after compaction.

[0018] Preferably, the slope surface in step 1 should be trimmed into a stepped manner with backfilling in layers of 30 cm each, and the compaction degree should be ≥90%.

[0019] Preferably, in step 2, the middle layer of reinforced gangue blocks has a particle size of 20-50 mm, forming a composite with a compressive strength of 3.5-5.0 MPa, and the density sensor detects a target slurry density of 1.6-1.8 g / cm 3 .

[0020] Preferably, in step 2: the middle layer reinforcement also includes automatically adjusting the water supply in case of abnormality to ensure fluidity and improve the compaction effect. The cement hydration product can effectively bond the coal gangue aggregate, improve the integrity of the structure, complete the reinforcement of the middle layer, and improve the firmness of use.

[0021] Preferably, in step 1, a concrete retaining wall is built in the collapsed area to prevent the filling material from slipping, and a drainage channel is provided to avoid erosion by accumulated water.

[0022] Preferably, in step five, drought-tolerant shrubs such as Amorpha fruticosa and herbaceous plants are planted on the surface.

[0023] (3) Beneficial effects

[0024] The present invention provides a method for restoring the ecology of geological disaster areas in mining areas using coal gangue. It has the following beneficial effects:

[0025] 1. The present invention adds: coal gangue, cement, lime and fly ash. The coal gangue serves as aggregate to enhance the compressive strength, and the cement and fly ash form a gelling network to improve the bearing capacity. The lime-fly ash system can reduce shrinkage cracks and optimize structural stability. Secondly, the mixture has outstanding environmental benefits. It can make large-scale use of coal gangue (more than 80%) and fly ash (15%-25%) to reduce solid waste accumulation. At the same time, lime can solidify heavy metals and reduce pollution risks. Therefore, through the mixed addition of the structure, environmental protection is improved, resource recycling is increased for ecological restoration of mining areas, and the collapse risk of disaster areas is protected.

[0026] 2. The present invention is provided with: middle layer reinforcement, which uses cement and fly ash in the bottom foundation to form a gelling network to improve the bearing capacity, and the bubbles in the cement mixing process can be discharged by the vibration rod in the middle layer reinforcement, so as to achieve a more solid and stronger firmness. In addition, the density sensor is used to detect the slurry density in real time, which can achieve stronger reinforcement of the middle layer structure, and has stronger firmness and stability, which is beneficial to the safety of the mining area after restoration.

[0027] 3. The present invention is provided with: seedlings. After the repair is completed, drought-resistant shrub seeds and seedlings can be spread on the surface, and the roots are used to consolidate the slope and gradually restore the ecological function, which increases the beauty and ecological environment while increasing the strength of the soil and is less likely to cause landslide risks. DETAILED DESCRIPTION

[0028] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0029] Example 1:

[0030] The embodiment of the present invention provides a method for restoring the ecology of a mining area affected by geological disasters using coal gangue, comprising the following specific restoration steps:

[0031] Step 1: Clearing and constructing the collapsed area: Remove loose debris and dangerous rocks from the collapsed area, and trim the slope to enhance the adhesion of the fill. The slope should be trimmed into a stepped pattern with 30cm layers of backfill, with a compaction level of ≥90%. Concrete retaining walls should be built in the collapsed area to prevent the fill from slipping, and drainage channels should be provided to prevent water erosion.

[0032] Step 2: Gangue repair:

[0033] Bottom foundation: Use Class II coal gangue with a particle size of 100mm mixed with cement and soil in a ratio of 3:3:2. Coal gangue is used as aggregate to enhance compressive strength. Cement and fly ash form a gelling network to improve bearing capacity. 3% of lime and 10% of fly ash are added to the total weight of the mixture. The lime-fly ash system can reduce shrinkage cracks and optimize structural stability. The bottom reinforcement improves the hydration reaction activity between the coal gangue surface and cement through chemical excitation, enhances the bonding strength of the coal gangue interface, and forms an anti-skid base layer after compaction to reduce solid waste accumulation. At the same time, lime can solidify heavy metals and reduce pollution risks. At the same time, for the bottom foundation, within the allowable range of repair, the foundation can be made into a triangular structure in the middle of the back side to improve stable support. Steel bars are passed through the soil to improve the firmness of use, which will increase the firmness of the bottom foundation and prevent the risk of secondary collapse.

[0034] Middle layer reinforcement: After the gangue blocks are mixed with cement, they can form a composite with high compressive strength. The bubbles in the gangue blocks mixed with cement are discharged by a vibrating rod. The density sensor detects the slurry density in real time. The middle layer reinforcement gangue blocks have a particle size of 20mm and form a composite with a compressive strength of 3.5MPa. The density sensor detects the slurry density target value of 1.6g / cm 3 , automatically adjust the water supply to ensure fluidity in case of abnormality, improve the compaction effect, the cement hydration product can effectively bond the coal gangue aggregate, improve the integrity of the structure, complete the reinforcement of the middle layer, improve the firmness of use, and benefit the safety of the mine area after restoration;

[0035] Surface restoration: Cover with a mixture of coal gangue particles ≤30mm, organic fertilizer, and water-retaining agent to provide a substrate for subsequent vegetation planting;

[0036] Step 3: Waterproof protection: Lay a geomembrane or asphalt waterproof layer between the middle layer and the surface layer to prevent the leakage of harmful substances from the coal gangue and pollute the surrounding environment. Drainage ditches need to be opened to allow water to circulate in designated locations to reduce the risk of collapse caused by accumulation;

[0037] Step 4: Slope solidification: Use steel mesh to anchor the filler or spray concrete to further enhance the anti-scouring ability and improve the firmness of the slope, making it less susceptible to rainwater erosion;

[0038] Step 5: Geological restoration: After the restoration is completed, drought-tolerant shrub seeds and seedlings can be spread on the surface to use the root system to consolidate the slope and gradually restore the ecological function. Drought-tolerant shrubs such as Amorpha fruticosa and herbaceous plants can be planted on the surface to use the root system to consolidate the slope and gradually restore the ecological function. This will increase the beauty and ecological environment while also increasing the strength of the soil, making it less likely to have a landslide risk.

[0039] Example 2:

[0040] The difference between this embodiment and the first embodiment is that: a method for restoring the ecology of a mining area with geological disasters using coal gangue includes the following specific restoration steps:

[0041] Step 1: Clearing and constructing the collapsed area: Remove loose debris and dangerous rocks from the collapsed area, and trim the slope to enhance the adhesion of the fill. The slope should be trimmed into a stepped pattern with 30cm layers of backfill, with a compaction level of ≥90%. Concrete retaining walls should be built in the collapsed area to prevent the fill from slipping, and drainage channels should be provided to prevent water erosion.

[0042] Step 2: Gangue repair:

[0043] Bottom foundation: Use Class II coal gangue with a particle size of 30mm, mixed with cement and soil in a ratio of 3:3:2, and add 5% of the total weight of the mixture, lime, and 15% of fly ash. The bottom reinforcement uses chemical stimulation to enhance the hydration reaction activity between the coal gangue surface and cement, strengthen the bond strength of the coal gangue interface, and form an anti-slip base layer after compaction;

[0044] Middle layer reinforcement: After the gangue blocks are mixed with cement, they can form a composite with high compressive strength. The bubbles in the gangue blocks mixed with cement are discharged by a vibrating rod. The density sensor detects the slurry density in real time. The middle layer reinforcement gangue blocks have a particle size of 50mm and form a composite with a compressive strength of 5.0MPa. The density sensor detects the target slurry density of 1.8g / cm 3 , automatically adjust the water supply to ensure fluidity in case of abnormality, improve the compaction effect, the cement hydration product can effectively bond the coal gangue aggregate, improve the integrity of the structure, complete the reinforcement of the middle layer, and improve the firmness of use;

[0045] Surface restoration: Cover with a mixture of coal gangue particles ≤30mm, organic fertilizer, and water-retaining agent to provide a substrate for subsequent vegetation planting;

[0046] Step 3: Waterproof protection: Lay a geomembrane or asphalt waterproof layer between the middle layer and the surface layer to prevent the leakage of harmful substances from the coal gangue and pollute the surrounding environment. Drainage ditches need to be opened to allow water to circulate in designated locations to reduce the risk of collapse caused by accumulation;

[0047] Step 4: Slope solidification: Use steel mesh to anchor the filler or spray concrete to further enhance the anti-scouring ability and improve the firmness of the slope, making it less susceptible to rainwater erosion;

[0048] Step 5: Geological restoration: After the restoration is completed, drought-tolerant shrub seeds and seedlings can be spread on the surface, using the root system to consolidate the slope and gradually restore the ecological function. Drought-tolerant shrubs such as Amorpha fruticosa and herbaceous plants can be planted on the surface.

[0049] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for restoring the ecology of a mining area affected by geological disasters using coal gangue, characterized in that: The specific repair steps include the following: Step 1: Cleaning and constructing the collapsed area: remove loose gravel and dangerous rocks in the collapsed area, and trim the slope to enhance the adhesion of the filling; Step 2: Gangue repair: Bottom foundation: Use Class II coal gangue with a particle size of 30-100mm mixed with cement and soil in a ratio of 3:3:2, and add 3%-5% of lime and 10%-15% of fly ash based on the total weight of the mixture; Middle layer reinforcement: After the coal gangue blocks are mixed with cement, they can form a composite with high compressive strength. The bubbles in the coal gangue blocks after mixing with cement are discharged through a vibrating rod, and the density sensor detects the slurry density in real time. Surface restoration: Cover with a mixture of coal gangue particles ≤30mm, organic fertilizer, and water-retaining agent to provide a substrate for subsequent vegetation planting; Step 3: Waterproof protection: Lay a geomembrane or asphalt waterproof layer between the middle layer and the surface layer to prevent the leakage of harmful substances from coal gangue and pollute the surrounding environment; Step 4: Slope solidification: Use steel mesh to anchor the filler or spray concrete to further improve the scour resistance; Step 5: Geological restoration: After the restoration is completed, drought-resistant shrub seeds and seedlings can be spread on the surface to use the root system to consolidate the slope and gradually restore the ecological function.

2. The method for restoring the ecology of a mining area geological disaster area using coal gangue according to claim 1, characterized in that: In the step 2, the bottom layer is reinforced by chemically stimulating the hydration reaction activity between the gangue surface and cement, thereby enhancing the bonding force of the gangue interface and forming an anti-skid base layer after compaction.

3. The method for restoring the ecology of a mining area geological disaster area using coal gangue according to claim 1, characterized in that: In step 1, the slope surface should be trimmed into a stepped pattern with backfilling in layers of 30 cm each, and the compaction degree should be ≥90%.

4. The method for restoring the ecology of a mining area geological disaster area using coal gangue according to claim 1, characterized in that: In step 2, the middle layer of reinforced coal gangue blocks has a particle size of 20-50 mm, forming a composite with a compressive strength of 3.5-5.0 MPa. The density sensor detects the target slurry density of 1.6-1.8 g / cm 3 .

5. The method for restoring the ecology of a mining area geological disaster area using coal gangue according to claim 4, characterized in that: In step 2: the middle layer reinforcement also includes automatically adjusting the water supply in case of abnormality to ensure fluidity and improve the compaction effect. The cement hydration product can effectively bond the coal gangue aggregate, improve the integrity of the structure, complete the reinforcement of the middle layer, and improve the firmness of use.

6. The method for restoring the ecology of a mining area geological disaster area using coal gangue according to claim 1, characterized in that: In step 1, a concrete retaining wall is constructed in the collapsed area to prevent the filling material from sliding, and a drainage channel is required to avoid water erosion.

7. The method for restoring the ecology of a mining area geological disaster area using coal gangue according to claim 1, characterized in that: In the step 5, drought-tolerant shrubs such as Amorpha fruticosa and herbaceous plants are planted on the surface.