Two-step strip type stoping subsequent filling mining method based on small compensation space

Abstract

The invention relates to a two-step strip-type stoping subsequent filling mining method based on a small compensation space, which comprises the following steps of: S1, stoping preparation: determining the stoping length of an ore block, dividing the ore block into a plurality of stoping units, and constructing a stoping roadway which goes uphill in advance and is used as a first mining unit in the stoping unit in the center of the ore block; s2, mining preparation and cutting; s3, stoping and ore breaking are carried out, shallow hole side collapse is constructed on the two sides of the first uphill, and stoping is gradually carried out; s4, ore removal: after ore caving is finished, ore removal is performed, and caved ore is transported and unloaded to a draw shaft; and S5, continuous mining is conducted in the ore blocks, and after filling of the first mining unit is completed, the adjacent stopes are subjected to stoping. According to the method, the construction of one uphill in each stoping unit is reduced to the construction of only one uphill in advance in the whole ore block, so that the accurate mining work amount is greatly reduced, the stoping cost is controlled, and the labor intensity is reduced; the combined supporting structure with the filling body on one side and the solid body on the other side is formed during two-step stoping, and the safety of two-step stoping is effectively guaranteed.

Description

Technical Field

[0001] This application relates to the technical field of underground mining, and in particular to a two-step strip mining followed by backfilling mining method based on small compensation space. Background Technology

[0002] For a long time, thin, gently dipping ore bodies with large angles (15°–35°) have been recognized as difficult to mine in underground metal and non-metal mines due to their unique occurrence conditions. On the one hand, the angle of the ore body is smaller than the natural angle of repose of the ore, which means that the collapsed ore cannot rely on its own weight to flow away, making it difficult to extract the ore. On the other hand, traditional methods such as ore retention, sublevel open area backfilling, and upward horizontal stratification not only involve a large amount of mining and cutting work, but also inevitably require operation in an environment surrounded by backfill bodies, resulting in high labor intensity, high mining costs, and low efficiency, which is not in line with the development trend of safe and efficient mine production.

[0003] Therefore, it is necessary to improve traditional mining methods to achieve safe and efficient mining of gently dipping thin ore bodies with large angles (15° to 35°). Summary of the Invention

[0004] To achieve safe and efficient mining of gently dipping thin ore bodies at large angles, this application provides a two-step strip mining followed by backfilling mining method based on a small compensation space.

[0005] The technical solution provided in this application for a two-step strip mining followed by backfilling mining method based on small compensation space adopts the following: A two-step strip mining followed by backfilling method based on small compensation space includes the following steps: S1. Preparation for mining: Determine the mining length of the ore block and divide it into multiple mining units by constructing the transport roadway along the vein in the upper and lower middle sections. Construct a mining roadway in the mining unit in the center of the ore block as the first mining unit. S2. Mining preparation and cutting: The mining preparation project of the ore block includes two mid-section along-vein transport roadways, the central incline of the ore block, the electric scraper ore extraction roadway, the pedestrian ventilation inclines on both sides of the ore block, and the sand roadway connecting each mining unit. S3. Mining and ore cutting: shallow holes are drilled on both sides of the previously constructed uphill section for side collapse, and mining is gradually withdrawn. S4. Mining: After the caving operation is completed, the ore is mined and the collapsed ore is transported to the pass. S5. Continuous mining within the ore block, after the initial mining unit is filled, the adjacent mining area is mined back.

[0006] Furthermore, in step S5, when mining adjacent mining areas, no further cutting and uphill sections are constructed within the adjacent mining areas to serve as mining roadways.

[0007] Furthermore, in step S5, when mining adjacent stopes, the working gap between the backfill and the adjacent stopes is used as a small compensation space, and the blast holes of the blasting operation are deflected towards the working gap at a set opening angle.

[0008] Furthermore, in step S5, when mining adjacent mining areas, the sand tunnel and the working gap are used as free face side collapses, and the mining of the entire block is completed in a cyclical manner.

[0009] Furthermore, during the second-step mining of the adjacent stope, drilling operations are carried out on the side of the second-step stope near the working gap, with at least three rows of blast holes constructed in the vertical direction, controlling the mining width at 1.4 to 1.7m to reduce dilution loss, and the row spacing at 0.6 to 0.8m; When the blast holes are opened, they are tilted towards the working gap side, and the sand tunnel and the working gap are used as free surfaces for side collapse. The blast holes at the top are used for smooth blasting to control the top plate. The first lateral collapse consists of 4-5 rows, with a hole spacing of 0.7-0.8m, a blasting advance of 2.5m, and a span of 3.5-4m.

[0010] Furthermore, in step S1, pillars are reserved at the top and bottom of the mining unit to protect the intermediate haulage roadway.

[0011] Furthermore, in step S3, the ore block is divided into several mining areas at equal intervals of 5 to 7 meters along the vein direction, with each mining area serving as the smallest mining unit, and the mining unit in the center of the ore block serving as the first mining unit.

[0012] Furthermore, after the initial mining unit is completed, mining gradually continues to both sides of the ore block until the entire ore block is mined out.

[0013] Furthermore, during the mining at the end of the first uphill section, three rows of reinforcing holes are arranged at the end position, with multiple holes in each row, a row spacing of 0.6-0.8m, and a hole spacing of 0.5-0.6m; the subsequent normal side-crashing rows have a row spacing of 0.6-0.8m and a hole spacing of 0.7-0.8m, with 3-5 rows of ore each time.

[0014] Furthermore, in step S2, during the mining preparation process, the dimensions of the intermediate section along the vein transport roadway are 2.2m × 2.4m, the dimensions of the sand roadway are 1.8m × 1.8m, the dimensions of the initial uphill section are 2.5m × 1.8m, and the dimensions of the electric scraper ore extraction roadway are 2m × 1.8m.

[0015] In summary, the beneficial technical effects of this application are as follows: 1. This application is applicable to thin ore bodies with a dip angle of 15° to 35°, stable or moderately stable ore and rock, and a thickness of less than 2m. It can greatly reduce the amount of preparation work for mining blocks, save blasting materials, and improve the safety of two-step mining operations. It is of great significance for reducing underground labor intensity and improving mining efficiency. It can realize the safe and efficient mining of thin ore bodies with a dip angle of 15° to 35°, which is in line with the development trend of safe and efficient production in mines. 2. The mining method described in this application has a simple cutting process, including a central incline, a sand tunnel connecting each mining unit, a pedestrian ventilation incline on both sides of the ore block, and an electric scraper ore extraction path. Compared with the traditional two-step strip mining followed by backfilling mining method, the construction of an incline for each mining unit is reduced to only one incline for the entire ore block, which greatly reduces the amount of preparation work, reduces the amount of slot hole drilling, reduces the additional consumption of blasting materials, effectively reduces the underground labor intensity and controls mining costs. 3. The mining method of this application differs from the traditional two-step mining method in that both sides are surrounded by backfill. The method of this application forms a "solid + backfill" combined support structure with one side of backfill and the other side of solid during the two-step mining, which improves the stability of the stope and effectively ensures the safety of the two-step mining. Attached Figure Description

[0016] Figure 1 This is a top view of the distribution of ore body mining units according to an embodiment of this application; Figure 2 It is along Figure 1 Schematic diagram of the cross-sectional structure along line AA; Figure 3 It is along Figure 1 Schematic diagram of the cross-sectional structure of the middle BB line; Figure 4 This is a top view schematic diagram of the two-step drilling process according to an embodiment of this application; Figure 5 This is a front view schematic diagram of the two-step drilling process according to an embodiment of this application.

[0017] Explanation of reference numerals in the attached figures: 1. Lower middle section along the vein transport roadway; 2. Upper middle section along the vein transport roadway; 3. First uphill roadway; 4. Personnel ventilation uphill roadway; 5. Sand roadway; 6. Electric scraper ore exit roadway; 7. Filling retaining wall; 8. Working interval; 9. Blasting hole. Detailed Implementation

[0018] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] This application discloses a two-step strip mining followed by backfilling method based on a small compensation space. (Refer to...) Figure 1 , Figure 2 and Figure 3 It includes the following steps: S1. Preparation for mining: Determine the mining length of the ore block and divide it into multiple mining units in the upper and lower middle sections of the construction of the haulage roadway along the vein. In the mining unit in the center of the ore block, construct a mining roadway with the first mining unit as the first mining unit. In addition, ore pillars are reserved at the top and bottom of the mining unit to protect the middle section haulage roadway.

[0020] S2. Mining preparation and cutting: The mining preparation project includes the lower middle section along the vein transport roadway 1, the upper middle section along the vein transport roadway 2, the central advance uphill roadway 3, the electric scraper ore extraction access roadway 6, the pedestrian ventilation uphill roadway on both sides of the ore block 4, and the sand roadway 5 connecting each mining unit; among which, in the mining preparation project, the size of the middle section along the vein transport roadway is 2.2m×2.4m, the size of the sand roadway 5 is 1.8m×1.8m, the size of the advance uphill roadway 3 is 2.5m×1.8m, and the size of the electric scraper ore extraction access roadway 6 is 2m×1.8m.

[0021] S3. Mining and ore cutting: Shallow-hole lateral caving is carried out on both sides of the initial incline 3, with gradual retreat mining. Specifically, the ore block is divided into several stopes at intervals of 5-7m along the vein direction, with each stope serving as the smallest mining unit. The central mining unit of the ore block is designated as the first mining unit. After the first mining unit is completed, mining gradually proceeds towards both sides of the ore block until the entire block is mined. Shallow-hole ore cutting is used at the end of the initial incline 3. Since only one side of the initial incline 3 provides a free blasting face, three rows of reinforcing holes with a diameter of 42mm are arranged at the end position, with four holes per row, a row spacing of 0.6-0.8m, and a hole spacing of 0.5-0.6m. Subsequent normal lateral caving rows have a row spacing of 0.6-0.8m and a hole spacing of 0.7-0.8m, with 3-5 rows of ore cuts per caving operation.

[0022] S4. Mining: After the blasting is completed, the ore is mined and the blasted ore is transported to the pass. Specifically, the blasting fumes from the working face are vented using a local fan, and the ore is mined through the ore mining access road 6 using an electric scraper and a railcar. The railcar then transports the blasted ore to the pass.

[0023] S5. Continuous mining within the block: After the initial mining unit is backfilled, a backfill retaining wall 7 is constructed, and adjacent stopes are mined. Specifically, when mining adjacent stopes, no further cutting is carried out to create mining roadways within the adjacent stopes; the working gap 8 between the backfill and the adjacent stopes is used as a small compensation space, and the blast holes 9 of the blasting operation are deflected towards the working gap 8 at a set opening angle; and the sand roadway 5 and the working gap 8 are used as free face side blasting, and the entire block is mined in a cyclical manner.

[0024] Furthermore, when mining adjacent stops in the second stage, the initial uphill construction 3 is no longer carried out; instead, the working gap 8 formed between the backfill body of the first-stage stop and the second-stage stop is used as a small compensation space for mining. For details, refer to... Figure 4 and Figure 5 Drilling operations are carried out on the side of the two-step mining area near the working gap 8, with at least three rows of blast holes 9 constructed in the vertical direction, controlling the mining width at 1.4 to 1.7m to reduce dilution loss, and the row spacing at 0.6 to 0.8m; When the blast hole 9 is opened, it is at a certain angle and deviates to the side of the working gap 8. The purpose is to use the sand tunnel 5 and the working gap 8 as free surfaces for side collapse, and the blast hole 9 at the top is used for smooth blasting to control the roof. The first lateral collapse consists of 4-5 rows, with a hole spacing of 0.7-0.8m, a blasting advance of 2.5m, and a span of 3.5-4m.

[0025] The working process of this application will now be described in a common application scenario. It should be noted that this common implementation scheme should not be used as the basis for determining the essential features for understanding the technical problem claimed to be solved by this application; it is merely an example.

[0026] In a specific example of a ore block, the block width is 60–70 m, the vertical height is 20–30 m, the length along the diagonal of the ore body is 50–60 m, and the thickness is the same as that of a thin ore body. The corresponding mining length is 40–50 m. Therefore, when dividing the ore block into mining units, each mining unit is 6 m wide and equal in length to the block. A single block is divided into 10–11 mining units, with the central mining unit designated as the first mining unit.

[0027] Therefore, the mining method proposed in this application is highly advantageous for the efficient mining of gently dipping thin ore bodies with relatively large ore body angles (15-35°), good surrounding rock conditions, and stable or moderately stable roofs. Specifically, a ore block is divided along the strike of the ore body at 60-70m intervals. Based on the surrounding rock conditions, a mining unit is divided every 6m within the ore block. First, a drilling roadway (2.5m × 1.8m) is constructed along the dip of the ore body in the middle of the central mining unit of the ore block. The mining operation of the first mining unit is completed by retreating from the upper middle section to the lower middle section within the drilling roadway.

[0028] After the empty area of ​​the first mining unit is filled, when mining adjacent mining units, the working gap 8 between the filling body and the mining unit is used as a small compensation space, and the mining operation of the mining unit is carried out by wedge-shaped slotting. An electric scraper chamber is arranged on one side of the vein roadway in the lower middle section, and the entire block is mined by electric scraper. This method can greatly reduce the amount of preparation work for the mining block, save blasting materials, and improve the safety of the two-step mining operation. It is of great significance for reducing underground labor intensity and improving mining efficiency.

[0029] Furthermore, during the second-stage mining process, there is no need to go uphill for construction, which significantly reduces the amount of preparation work, reduces the amount of drilling work for slotting holes, reduces the extra consumption of blasting materials, and effectively reduces the labor intensity underground and controls mining costs.

[0030] Furthermore, compared to the traditional two-step strip mining followed by backfilling method, the two-step strip mining followed by backfilling method based on small compensation space proposed in this application avoids the situation where both sides of the stope are filled with backfill during the two-step mining. After blasting, a support structure of "solid + backfill" is formed on both sides of the empty area, which effectively improves the stability of the empty area and makes the mining operation safer.

[0031] The implementation principle of a two-step strip mining followed by backfilling method based on small compensation space in this application embodiment is as follows: Divide the ore body into blocks 60-70m apart. Based on the surrounding rock conditions, divide the ore body into mining units every 6m. First, construct a rock drilling roadway in the middle of the central mining unit of the ore body along the dip of the ore body. Then, in the rock drilling roadway, retreat mining from the upper middle section to the lower middle section to complete the mining operation of the first mining unit.

[0032] After the empty area of ​​the first mining unit is filled, when mining adjacent mining units, the working gap 8 between the filling body and the mining unit is used as a small compensation space, and the mining operation of the mining unit is carried out by wedge-shaped slotting. An electric scraper chamber is arranged on one side of the lower middle section along the vein transport roadway 1, and the entire block is mined by electric scraper. This method can greatly reduce the amount of preparation work for the mining block, save blasting materials, and improve the safety of the two-step mining operation. It is of great significance for reducing underground labor intensity and improving mining efficiency.

[0033] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," "third," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "an" or "a" and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms "comprising" or "including" and similar terms mean that the elements or objects preceding "comprising" or "including" encompass the elements or objects listed following "comprising" or "including" and their equivalents, and do not exclude other elements or objects. "Above," "below," "left," "right," etc., are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0034] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A two-step strip mining followed by backfilling method based on small compensation space, characterized in that, Includes the following steps: S1. Preparation for mining: Determine the mining length of the ore block and divide it into multiple mining units by constructing the transport roadway along the vein in the upper and lower middle sections. Construct a mining roadway in the mining unit in the center of the ore block as the first mining unit. S2. Mining preparation and cutting: The mining preparation project of the ore block includes two mid-section along-vein transport roadways, the central incline of the ore block, the electric scraper ore extraction roadway, the pedestrian ventilation inclines on both sides of the ore block, and the sand roadway connecting each mining unit. S3. Mining and ore cutting: shallow holes are drilled on both sides of the incline for side collapse, and mining is gradually withdrawn. S4. Mining: After the caving operation is completed, the ore is mined and the collapsed ore is transported to the pass. S5. Continuous mining within the ore block, after the initial mining unit is filled, the adjacent mining area is mined back.

2. The two-step strip mining followed by backfilling mining method based on small compensation space according to claim 1, characterized in that, In step S5, when mining adjacent mining areas, no further cutting and uphill construction is carried out within the adjacent mining areas to serve as mining roadways.

3. The two-step strip mining followed by backfilling mining method based on small compensation space according to claim 1, characterized in that, In step S5, when mining adjacent stopes, the working gap between the backfill and the adjacent stopes is used as a small compensation space, and the blast holes of the blasting operation are biased towards the working gap at a set opening angle.

4. The two-step strip mining followed by backfilling mining method based on small compensation space according to claim 3, characterized in that, In step S5, when mining adjacent mining areas, the sand tunnel and the working gap are used as free face side collapses, and the mining of the entire block is completed by repeated cycles.

5. The two-step strip mining followed by backfilling mining method based on small compensation space according to claim 4, characterized in that, When carrying out the second-step mining of the adjacent stope, drilling operations are carried out on the side of the second-step stope near the working gap. At least three rows of blast holes are constructed in the vertical direction, and the mining width is controlled at 1.4 to 1.7m to reduce dilution loss, with a row spacing of 0.6 to 0.8m. When the blast holes are opened, they are tilted towards the working gap side, and the sand tunnel and the working gap are used as free surfaces for side collapse. The blast holes at the top are blasted with smooth surfaces to control the top plate. The first lateral collapse consists of 4-5 rows, with a hole spacing of 0.7-0.8m, a blasting advance of 2.5m, and a span of 3.5-4m.

6. The two-step strip mining followed by backfilling mining method based on small compensation space according to claim 1, characterized in that, In step S1, pillars are reserved at the top and bottom of the mining unit to protect the intermediate haulage roadway.

7. The two-step strip mining followed by backfilling mining method based on small compensation space according to claim 1, characterized in that, In step S3, the ore block is divided into several mining areas at equal intervals of 5-7m along the vein direction. The mining area is the smallest mining unit, and the mining unit in the center of the ore block is the first mining unit.

8. The two-step strip mining followed by backfilling method based on small compensation space according to claim 7, characterized in that, After the initial mining unit is completed, mining gradually proceeds to both sides of the ore block until the entire ore block is mined out.

9. The two-step strip mining followed by backfilling method based on small compensation space according to claim 1, characterized in that, When mining at the end of the first uphill section, three rows of reinforcing holes are arranged at the end position, with multiple holes in each row, a row spacing of 0.6-0.8m, and a hole spacing of 0.5-0.6m; the subsequent normal side-cracking rows have a row spacing of 0.6-0.8m and a hole spacing of 0.7-0.8m, with 3-5 rows of ore each time.

10. A two-step strip mining followed by backfilling method based on small compensation space according to claim 9, characterized in that, In step S2, during the mining preparation project, the dimensions of the intermediate section along the vein transport roadway are 2.2m × 2.4m, the dimensions of the sand roadway are 1.8m × 1.8m, the dimensions of the initial uphill section are 2.5m × 1.8m, and the dimensions of the electric scraper ore extraction roadway are 2m × 1.8m.

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