Upward drift filling mining process for mining

Abstract

The invention relates to the technical field of mining, in particular to an upward drift filling mining process for mining, which comprises the following steps: a blasting method: adopting medium-length hole subsection blasting, dividing a drift into a plurality of subsections, arranging vertical fan-shaped medium-length holes in each subsection, enabling the diameter of each blast hole to be 60-80mm, the bottom distance of each hole to be 1.2-1.8 m and the row distance to be 1.0-1.5 m, adopting a non-electric millisecond detonator millisecond blasting to perform millisecond blasting, and forming a vertical fan-shaped medium-length hole in each subsection; the delay time of the detonators of the adjacent sections is 25-50 ms; the filling material is a cemented filling material, and the cemented filling material is formed by mixing tailings, cement and water, the whole mine field can be communicated through the mining ore drawing winze, the courtyard connection way and the pedestrian ventilation courtyard by utilizing the connection channel, and it can be ensured that the interior of the mine field is kept in a good ventilation state; harmful gas and dust generated by blasting are discharged in time, the mining operation environment is improved, and the body health of operators is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of mining, in particular to an upward approach filling mining process for mining. Background Art

[0002] In-fill mining is a widely used method in mining operations. It involves filling the goaf with backfill material after the mine is mined to support the roof and ensure the safety and stability of subsequent mining operations.

[0003] The traditional upward-entry backfill mining process leaves much to be desired. For example, the lack of precise control during blasting can easily damage the ore layer and surrounding structures, increasing the likelihood of accidents. Furthermore, the inadequate reinforcement techniques used for channels such as ore chutes, access shafts, and pedestrian ventilation shafts make it difficult to ensure their structural strength and stability. This can lead to collapse and other problems during mining, negatively impacting the operation of the entire mining system. Summary of the Invention

[0004] The object of the present invention is to provide an upward approach filling mining process for mining, so as to solve the problems raised in the above background technology.

[0005] The technical solution of the present invention is: a mining process for upward approach filling, comprising the following steps: Blasting method: Medium-deep hole segmented blasting is adopted, and the approach is divided into multiple segments. Vertical fan-shaped medium-deep holes are arranged in each segment. The blasthole diameter is 60-80mm, the hole bottom distance is 1.2-1.8m, and the row spacing is 1.0-1.5m. Non-electric millisecond detonator micro-difference blasting is adopted, and the delay time of adjacent segment detonators is 25-50ms. Filling material: Cementitious filling material is used. The cementitious filling material is a mixture of tailings, cement and water, wherein the mass ratio of tailings, cement and water is (8-12):1:(2-3). The slump of the cementitious filling material is controlled at 180-220mm. Reinforcement: The outer walls of the ore chute, skylight connecting road and pedestrian ventilation skylight are reinforced with reinforced concrete. The diameter of the steel bars in the reinforced concrete is 12 to 16 mm, the spacing between the steel bars is 150 to 200 mm, the concrete strength grade is not less than C30, and the thickness of the reinforced concrete reinforcement layer is 300 to 500 mm.

[0006] Preferably, the segmented height of the medium-deep hole segmented blasting is 8 to 12 m.

[0007] Preferably, the cementitious filling material needs to be stirred before filling, and the stirring time is not less than 3 minutes.

[0008] Preferably, the outer walls of the ore chute, skylight connecting road and pedestrian ventilation skylight need to be cleaned and roughened before being reinforced with reinforced concrete.

[0009] Preferably, the side hole angle of the vertical fan-shaped medium-deep hole is 45°-60°.

[0010] Preferably, a water reducer with a mass ratio of 0.1% to 0.3% is added to the cementitious filling material to improve the fluidity of the material.

[0011] Preferably, after blasting, the blasted ore is loosened and unloaded by combining mechanical shoveling with manual assistance.

[0012] Preferably, drainage pipes are provided in the reinforced concrete reinforcement layer, the diameter of the drainage pipes is 50 to 80 mm, and the pipes are arranged at intervals of 3 to 5 m.

[0013] Preferably, the mining method includes the following: Step 1: Maintain ventilation inside the mine by constructing ore chutes, access shafts, and pedestrian ventilation shafts. Step 2: Create a connecting passage inside the mine that connects to the ore chute, skylight, and pedestrian ventilation skylight to connect the entire mine and prevent the ore chute, skylight, or pedestrian ventilation skylight from collapsing. Step 3: First, the first ore to be mined is mined in intervals. After the mining is completed, it is backfilled with cemented filling materials. The unmined areas of the first ore to be mined are mined. After the mining is completed, it is also backfilled with cemented filling materials. At the same time, the mud and rock above the connecting channel are excavated so that the mud and rock produced are at the same height as the first ore to be mined; Step 4: First, the second ore to be mined is mined in intervals. After the mining is completed, it is backfilled with cemented filling materials. The unmined areas of the second ore to be mined are mined. After the mining is completed, it is also backfilled with cemented filling materials. At the same time, the mud and rock above the connecting channel are excavated so that the mud and rock produced are at the same height as the second ore to be mined; Step 5: First, the third ore to be mined is mined in intervals. After the mining is completed, it is backfilled with cementing filling materials. The unmined areas of the third ore to be mined are mined. After the mining is completed, cementing filling materials are also used to backfill. At the same time, the unbackfilled areas are backfilled. At this time, the mining of this mining area is completed.

[0014] The present invention provides an improved upward approach filling mining process for mining, which has the following improvements and advantages compared with the prior art: The use of medium-long hole segmented blasting and strict control of parameters such as blasthole diameter, hole bottom distance, row spacing and detonator delay time can effectively control the blasting range and intensity, reduce the damage to the ore layer and surrounding structures, and reduce the probability of safety accidents such as collapse; The outer wall of the ventilation shaft is reinforced with reinforced concrete, with clear requirements for the diameter, spacing, concrete strength grade, and thickness of the reinforcement layer. Cleaning and roughening are also performed before reinforcement to enhance the structural strength and stability of the ventilation shaft, ensuring the safe operation of the ventilation system during mining. Drainage pipes are installed in the reinforced concrete layer to promptly drain water around the ventilation shaft, preventing it from eroding and damaging the shaft structure, further improving the safety of mining operations. The segment height of the medium-long hole segmented blasting is set to 8 to 12 meters. Combined with the arrangement of vertical fan-shaped medium-long holes and appropriate side hole angles, the ore size after blasting can be made more uniform, facilitating subsequent mining operations. After blasting, the ore is removed by combining mechanical shoveling with manual assistance. This can not only give full play to the efficient operation capacity of the machinery, but also process some areas that are difficult for the machinery to reach through manual assistance, thereby improving the ore removal efficiency and ore recovery rate. The cementitious filling material should be stirred for no less than 3 minutes before filling, and the slump should be controlled between 180 and 220 mm. At the same time, a water-reducing agent with a mass ratio of 0.1% to 0.3% should be added to improve fluidity, which can ensure that the filling material has good workability and density, making the filling operation smoother and ensuring the filling quality; Interval mining and timely cement filling can effectively support the roof of the ore layer, reduce the settlement and deformation of the ore layer caused by mining, protect the geological structure of the mine, create good conditions for subsequent mining operations, and achieve sustainable mining of the mine; By opening connecting passages to connect the ore chute, the skylight access road and the pedestrian ventilation skylight, it is possible to prevent the collapse of any of the passages from affecting the operation of the entire mining system and ensure the continuity of mining; Cemented filling materials are made of a mixture of tailings, cement and water. The tailings generated during mining are used as the main component of the filling material, which realizes the resource utilization of tailings, reduces the amount of tailings piled up, and improves resource utilization. The use of interval mining and backfilling methods can fully mine the ore layer, reduce ore residue and waste, and improve ore recovery rate; By constructing ore chutes, skylight connecting roads and pedestrian ventilation skylights, and using connecting passages to connect the entire mine, we can ensure that the mine is well ventilated, discharge harmful gases and dust generated by blasting in a timely manner, improve the mining environment, and protect the health of workers. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further explained below in conjunction with the accompanying drawings and examples: Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 It is a schematic diagram of the mining sequence and filling structure of the present invention; Figure 3 It is a schematic diagram of the mining sequence and filling structure of the present invention; Figure 4 It is a schematic diagram of the mining sequence and filling structure of the present invention; Figure 5 It is a schematic diagram of the mining sequence and filling structure of the present invention; Figure 6 It is a schematic diagram of the mining sequence and filling structure of the present invention; Figure 7 It is a schematic diagram of the mining sequence and filling structure of the present invention.

[0016] Description of reference numerals: 1. Ore chute; 2. Skylight connecting road; 3. Pedestrian ventilation skylight; 4. Connecting passage; 5. First ore to be mined; 6. Second ore to be mined; 7. Third ore to be mined. DETAILED DESCRIPTION

[0017] The present invention is described in detail below, clearly and completely describing 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. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0018] The present invention provides an improved upward approach filling mining process for mining. The technical solution of the present invention is: like Figure 1 - Figure 7 As shown, a mining process for filling an upward approach for mining includes the following steps: blasting method: adopting medium-deep hole segmented blasting to divide the approach into multiple segments, arranging vertical fan-shaped medium-deep holes in each segment, with a blasthole diameter of 60-80 mm, a hole bottom distance of 1.2-1.8 m, and a row spacing of 1.0-1.5 m; adopting non-electric millisecond detonator micro-difference blasting, and a delay time of adjacent segment detonators of 25-50 ms; filling material: adopting cementitious filling material, which is a mixture of tailings, cement and water, wherein the mass ratio of tailings, cement and water is 8-12:1:2-3, and the slump of the cementitious filling material is controlled to be 180-220 mm; Reinforcement: The outer walls of the ore chute 1, the skylight connecting road 2 and the pedestrian ventilation skylight 3 are reinforced with reinforced concrete. The diameter of the steel bars in the reinforced concrete is 12 to 16 mm, the spacing between the steel bars is 150 to 200 mm, the concrete strength grade is not less than C30, and the thickness of the reinforced concrete reinforcement layer is 300 to 500 mm.

[0019] Furthermore, the segment height of medium-long hole segment blasting is 8 to 12 meters. The segment height of medium-long hole segment blasting is set to 8 to 12 meters. This range is based on the balance between mine geological conditions and blasting efficiency. When the segment height is less than 8 meters, the frequency of blasting operations increases, which will increase construction costs; when it exceeds 12 meters, the probability of uneven ore size increases, which is not conducive to subsequent mining. Under hard ore rock conditions, the segment height should be taken from the lower limit (8 to 10 meters). This can reduce the amount of ore and rock in a single blast and reduce the risk of roof collapse. If the ore rock joints are developed, it can be appropriately increased to 10 to 12 meters to reduce the number of segment constructions. This segment height needs to work in conjunction with the side hole angle (45°-60°) of the vertical fan-shaped medium-long hole. For example, when the segment height is 10 meters, the side hole angle is 50°, which can control the blasting funnel radius to 3 to 4 meters and ensure uniform ore collapse. Furthermore, cementitious backfill materials must be stirred for at least 3 minutes before filling. This ensures thorough mixing of the tailings, cement, and water. During the initial mixing period (0-1 minute), cement particles are initially dispersed; after 1-2 minutes, the tailings surface is coated with cement paste; after 2-3 minutes, the water reducer fully activates, and the material slump reaches the standard of 180-220 mm. If the mixing time is less than 3 minutes, cement lumps and tailings particle agglomeration may occur. Testing has shown that backfill materials stirred for 2 minutes have a 28-day compressive strength that is 15%-20% lower than materials stirred for the standard mixing time, and are more susceptible to shrinkage cracks after filling. It is recommended to use a twin-shaft forced mixer with a speed controlled at 40-60 rpm and a clearance of no more than 5 mm between the mixing blades and the barrel wall to ensure uniform mixing.

[0020] Furthermore, before reinforcing the ore chute 1, the skylight 2, and the pedestrian ventilation skylight 3 with reinforced concrete, the exterior walls of the ventilation shafts must be cleaned and roughened. This cleaning process removes impurities such as pumice and oil. This can be done using a high-pressure water jet (pressure ≥ 15 MPa) combined with manual chiseling. After cleaning, the surface flatness error should be ≤ 5 mm / m, as this will affect the bond between the reinforced concrete and the base layer. The roughening depth should be 5 to 10 mm.

[0021] Furthermore, the side hole angle of vertical fan-shaped medium-long holes is 45°-60°. Controlling the side hole angle of vertical fan-shaped medium-long holes within this range optimizes blasting stress distribution. A 45° side hole angle evenly distributes blasting energy, making it suitable for narrow access (width ≤ 4m) mining. A 60° side hole angle expands the blasting range and is suitable for wide access (4-6m) scenarios.

[0022] Furthermore, a water-reducing agent (such as a naphthalene-based high-efficiency water-reducing agent) at a mass ratio of 0.1% to 0.3% is added to the cementitious filling material to improve its fluidity. This addition reduces the attraction between cement particles through the adsorption-dispersion principle, thereby improving the fluidity of the cement paste. When the water-reducing agent dosage is 0.2%, the water consumption of the cementitious filling material can be reduced by 10% to 15%, while the slump remains at 180 to 220 mm. Below 0.1%, the water-reducing effect is not significant, and the material fluidity is insufficiently improved. Above 0.3%, retarded setting may occur, affecting the early strength of the filling material.

[0023] Furthermore, after blasting, the ore is loosened and unloaded by combining mechanical shoveling with manual assistance. After blasting, a hydraulic breaker is first used to loosen the large ore (the breaker's working pressure is 20-25 MPa), and then a scraper (bucket capacity 2-3 m 3 ) for mechanical shoveling.

[0024] Furthermore, drainage pipes with a diameter of 50 to 80 mm are set in the reinforced concrete reinforcement layer and are arranged at intervals of 3 to 5 m. Drainage pipes with a diameter of 50 to 80 mm are set in the reinforced concrete reinforcement layer. UPVC pipes or galvanized steel pipes are used. Fine stone concrete (strength grade ≥ C35) is used to fill the area around the pipes tightly to prevent displacement during concrete pouring.

[0025] Furthermore, the following mining methods are included: Step 1: The mine is kept ventilated by constructing a mine chute 1, a skylight connecting road 2 and a pedestrian ventilation skylight 3. The mine chute (1) has a diameter of 2 to 3 m and is supported by concrete (thickness 200 to 300 mm). The skylight connecting road (2) has a width of 3 to 4 m and a height of 2.5 to 3 m. An anchor rod (length 2 to 2.5 m, spacing 1 to 1.5 m) and a steel mesh is installed on the top. The pedestrian ventilation skylight (3) has a diameter of 1.5 to 2 m and is equipped with a ventilator (air volume ≥ 200 m 3 / min), ensure that the wind speed inside the mine is ≥0.25m / s; Step 2: A connecting passage 4 is opened inside the mine, which is connected to the ore chute 1, the skylight connecting road 2 and the pedestrian ventilation skylight 3, so that the entire mine is connected and any one of the ore chute 1, the skylight connecting road 2 or the pedestrian ventilation skylight 3 is prevented from collapsing. The connecting passage (4) is 2 to 2.5 m wide and 2 to 2.5 m high and is supported by reinforced concrete (300 to 500 mm thick). Reinforcement ribs (16 to 20 mm in diameter and 4 to 6 in number) are provided at the connection with the ore chute, the skylight connecting road and the pedestrian ventilation skylight to prevent stress concentration during collapse. Step 3: First, the first ore 5 to be mined is mined in intervals. After the mining is completed, it is backfilled with cemented filling materials. The area where the first ore 5 is mined is mined. After the mining is completed, it is also backfilled with cemented filling materials. At the same time, the mud and rock above the connecting channel 4 are excavated so that the mud and rock produced are at the same height as the first ore 5 to be mined; Step 4: First, the second ore 6 to be mined is mined in intervals. After the mining is completed, it is backfilled with cemented filling materials. The area where the second ore 6 is mined is mined is mined. After the mining is completed, it is also backfilled with cemented filling materials. At the same time, the mud and rock above the connecting channel 4 are excavated so that the mud and rock produced are at the same height as the second ore 6; Step 5: First, the third ore block 7 is mined in intervals. After mining is complete, it is backfilled with cementitious fill material. The unmined areas of the third ore block 7 are mined and backfilled with cementitious fill material. The unmined areas are then backfilled. This completes the mining of this area. The interval-mined blocks are 3-5 meters wide, with adjacent blocks spaced 2-3 meters apart. During backfilling, the cementitious fill material is poured in 3-5 layers, each 500-800 mm thick. The layers are vibrated to compaction (the vibrator is inserted more than 200 mm deep into the layer). The upper layers are poured only after the lower layer reaches 70% strength. When excavating the debris above the connecting channel, controlled blasting (charge per hole ≤ 0.5 kg) is used to ensure a height difference of ≤ 300 mm between the excavation surface and the ore block.

[0026] The above description is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A mining process for upward approach filling, characterized in that: The following steps are involved: Blasting method: Medium-deep hole segmented blasting is adopted. The approach is divided into multiple segments. Vertical fan-shaped medium-deep holes are arranged in each segment. The blasthole diameter is 60-80mm, the distance from the hole bottom is 1.2-1.8m, and the row spacing is 1.0-1.5m. Non-electric millisecond detonator micro-difference blasting is adopted, and the delay time of adjacent segment detonators is 25-50ms. Filling material: cementitious filling material is used, which is a mixture of tailings, cement and water, wherein the mass ratio of tailings, cement and water is (8-12):1:(2-3), and the slump of the cementitious filling material is controlled at 180-220mm; Reinforcement: The outer walls of the ore chute (1), the skylight connecting road (2) and the pedestrian ventilation skylight (3) are reinforced with reinforced concrete. The diameter of the steel bars in the reinforced concrete is 12 to 16 mm, the spacing between the steel bars is 150 to 200 mm, the concrete strength grade is not less than C30, and the thickness of the reinforced concrete reinforcement layer is 300 to 500 mm.

2. The upward filling mining process for mining according to claim 1 is characterized in that: The segmented height of the medium-deep hole segmented blasting is 8 to 12 meters.

3. The upward filling mining process for mining according to claim 1 is characterized in that: The cementitious filling material needs to be stirred before filling, and the stirring time should be no less than 3 minutes.

4. The upward approach filling mining process for mining according to claim 1 is characterized in that: Before the outer walls of the ore chute (1), the skylight connecting road (2) and the pedestrian ventilation skylight (3) are reinforced with reinforced concrete, the outer walls of the ventilation shaft need to be cleaned and roughened.

5. The upward approach filling mining process for mining according to claim 1 is characterized in that: The side hole angle of the vertical fan-shaped medium-deep hole is 45°-60°.

6. The upward filling mining process for mining according to claim 1 is characterized in that: The cementitious filling material is also added with a water reducing agent at a mass ratio of 0.1% to 0.3% to improve the fluidity of the material.

7. The upward filling mining process for mining according to claim 1 is characterized in that: After blasting, the blasted ore is loosened and unloaded using a combination of mechanical shoveling and manual assistance.

8. The upward filling mining process for mining according to claim 1 is characterized in that: Drainage pipes are arranged in the reinforced concrete reinforcement layer. The diameter of the drainage pipes is 50 to 80 mm and the pipes are arranged at intervals of 3 to 5 meters.

9. The upward approach filling mining process for mining according to claim 1, characterized in that: The following mining methods are included: Step 1: Maintain ventilation inside the mine by constructing ore chutes (1), skylight access roads (2) and pedestrian ventilation skylights (3); Step 2: Opening a connecting passage (4) inside the mine that is connected to the ore chute (1), the skylight connecting road (2) and the pedestrian ventilation skylight (3) to connect the entire mine and prevent the ore chute (1), the skylight connecting road (2) or the pedestrian ventilation skylight (3) from collapsing; Step 3: First, the first ore (5) to be mined is mined in intervals, and after the mining is completed, it is backfilled with cemented filling materials. The unmined area of the first ore (5) to be mined is mined, and after the mining is completed, it is also backfilled with cemented filling materials. At the same time, the mud and rock above the connecting channel (4) are excavated so that the mud and rock produced are at the same height as the first ore (5) to be mined; Step 4: First, the second ore (6) to be mined is mined in intervals, and after the mining is completed, it is backfilled with cemented filling materials. The unmined area of the second ore (6) to be mined is mined, and after the mining is completed, it is also backfilled with cemented filling materials. At the same time, the mud and rock above the connecting channel (4) are excavated so that the mud and rock produced are at the same height as the second ore (6) to be mined; Step 5: First, the third ore to be mined (7) is mined in intervals. After the mining is completed, it is backfilled with cementing filling materials. The unmined areas of the third ore to be mined (7) are mined. After the mining is completed, it is also backfilled with cementing filling materials. At the same time, the unbackfilled areas are backfilled. At this time, the mining of this mining area is completed.

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