CN103590831B - A kind of gentle dip is thin-the novel mining methods of middle thickness orebody - Google Patents

Abstract

The mining method of the gently inclined thin-medium-thick ore body of the present invention is to divide the ore body in a stope into two stope areas and recover mining step by step; at first, the stope area ( 1) For back mining, the ore body is directly caving in a single segment by using medium and deep hole blastholes; after the ore is mined, a certain empty area is formed as the stope area; (2) The free surface of back mining; The stope area (2) is mined, and the fan-shaped medium and deep hole blastholes are arranged perpendicular to the ore body inclination. The medium and deep hole blastholes are charged in sections. (1) The empty area formed by mining is blasted row by row on the free surface, and the ore in the stope area (2) is thrown into the empty area by explosive force. The method combines the pillarless segmental caving method and the explosive force transporting method, reduces the difficulty and workload of support, provides safer operation, lower mining cost and high labor productivity.

Description

A New Mining Method of Gently Inclined Thin-Medium Thick Orebody

technical field

The invention belongs to the technical field of mining engineering, and in particular relates to a novel mining method suitable for mining gently inclined thin-medium-thick ore bodies.

Background technique

Gently inclined thin-medium-thick ore bodies have brought many difficulties to mining due to their inherent conditions. For example, the ore cannot be released completely by its own weight, and problems such as large cutting ratio, low recovery rate, and high cost are prone to occur during the mining process. The mining methods for gently inclined ore bodies at home and abroad mainly include room and pillar method, comprehensive method, chassis funnel mining method, filling method and so on. The room-and-pillar method and the comprehensive method need to keep ore pillars in the stope, the ore recovery rate is low, and they are directly operated in the goaf, which has poor safety and requires roof support, which has complicated procedures and a large amount of work; the chassis funnel mining method It is easy to lead to problems such as large mining-to-cut ratio and high mining cost; while the filling method is complex in process and high in cost, and is economically unreasonable for the mining of non-precious metal gently inclined thin-medium thick deposits.

The mining of gently inclined thin-medium-thick ore bodies is a world-recognized mining problem, and the poor stability of ore rocks increases the difficulty of mining. With the development of science and technology, the research and practice of the mining of gently inclined thin-medium-thick ore bodies at home and abroad have also made continuous progress, mainly in the following aspects: the use of highly automated trackless self-excavation equipment has greatly improved the labor production efficiency of mining ; The development of support technology and the application of anchor trolley, shotcrete trolley, anchor cable and grouting support technology have improved support efficiency and improved safety conditions; the application of advanced equipment and technology has promoted new safe and efficient mining methods generation. The invention introduces a new mining method suitable for mining gently inclined thin-medium-thick ore bodies, which avoids potential safety hazards caused by working directly in the stope, improves operation safety, and reduces the difficulty and difficulty of stope roof support. The workload reduces the mining and cutting engineering volume of the gently inclined ore body mining, and improves the problem of difficulty in mining the gently inclined ore body. The mechanized operation of the trackless equipment is used, and the production efficiency is high.

Contents of the invention

The purpose of the present invention is to propose a novel mining method for gently inclined thin-medium-thick ore bodies, which combines the segmental caving method without bottom pillars and the explosive force transportation mining method, overcomes the shortcomings of a single mining method, and realizes Complementary advantages.

In order to realize the purpose of the present invention, propose following technical scheme:

The novel mining method of the present invention divides the ore body in one stope into two regions and mines in steps when mining a gently inclined thin-medium-thick ore body.

First, stope area 1 is mined using the pillarless segmental caving method. Because the thickness of the target ore body is not large, the ore body is directly caving in a single segment by using the middle and deep holes 10, and a certain empty area 12 is formed as the free surface of the stope area 2 after mining.

Then, the stope area 2 is mined using the explosive force transport mining method, and the fan-shaped middle and deep holes 10 are arranged perpendicular to the ore body inclination. The empty area 12 formed by mining in area 1 is blasted row by row on the free surface, and the ore in area 2 is thrown into the empty area 12 by explosive force.

After the stope mining is completed, part of the ore in the stope rock drilling road 5 will form a conical ore pile that cannot be shoveled out, and this part of the ore will be drilled in sections in the section transportation roadway 3 after the end of the lower section mining. Road 5 excavates slip mine well 11 and reclaims.

When adopting the novel mining method of the gently inclined thin-middle-thick ore body of the present invention, the technical points of forming the stope structure are as follows:

Mining standard engineering, the mining standard project includes segmental transport roadway 3, ore-out approach road 4 and rock drilling road 5. The mining quasi-engineering is arranged in the area where the surrounding rock is stable at the footwall of the ore body. The segmental transportation roadway 3 is arranged along the ore body trend, and the ore body is perpendicular to the direction of the ore body. A rock drilling road 5 is excavated along the ore body at a place 3 to 5 m below the bottom plate, and the rock drilling road 5 is connected to each ore-exiting road 4 . The width × height of the roadway section of the mining project is 3.2m × 3.4m, and the Boomer trolley and scraper are used for mechanized construction.

Cutting project, the cutting project mainly includes cutting patio 8 and cutting horizontal alley 9, the section of cutting patio 8 is 2.0m×2.0m, which is vertical or inclined patio. The cutting side lane 9 is to extend the ore-discharging approach 4 forward. During the grooving process, several rows of upward holes are constructed in the cutting lane 9, and the cutting trough is formed after blasting with the cutting patio 8 as the free surface.

The roadway support method mainly adopts prestressed bolt support and grouting long anchor cable support. 1. Under normal circumstances, the stability requirements can be met by using prestressed bolt support. The length of the bolt is 2.4m, the diameter is 18mm, the support mesh is 1.5m×1.5m, and the applied prestress is greater than 100KN. The exposed area of the roof of the T-shaped fork where the roadway meets is large, and the grouting long anchor cable is added for support. The anchor cable is 6.0m long and the mesh is 3.0m×3.0m. If the surrounding rock in some areas is broken or becomes loose due to the impact of blasting shock waves, reinforcement support shall be adopted, steel mesh shall be added, and wooden support or steel bracket shall be used if necessary.

The mining sequence, the mining sequence is for different segments, mining from top to bottom, and the top column 6 is reserved between the stopes of the upper and lower segments; in one segment, each mining approach 4 can be regarded as one mining The inter-column 7 is reserved between adjacent stopes; the recovery order of the segment can be recovered from the stope in the middle of the segment to both ends, or from one end of the segment to the other end.

Blasting ore removal, using fan-shaped medium-deep hole 10 blasting ore removal, using rock drilling rigs to drill holes, the depth of the blast hole depends on the situation, the hole depth generally does not exceed 30m, the hole diameter is 76mm, the bottom distance of the hole is 2.0m, and the row distance is 2.0 m.

After the blasting, use the scraper to extract the ore, and enter the rock drilling road 5 to extract the ore through the ore extraction approach 4 and the adjacent ore extraction approach 4. In the late stage of mining, part of the ore in the rock drilling road 5 will eventually form a cone-shaped ore pile, which cannot be shoveled out, and is recovered in the next section by using the small ore chute 11.

Ventilation airflow direction of the stope is as follows: fresh air is drawn out through the return air patio after washing the working face through the segmental transportation roadway 3, the ore exit roadway 4, and the rock drilling roadway 5. The single-headed working surface is air-supplied/extracted by the blower to ensure the working air quality.

In the early stage of stope recovery, the stope roof is supported by the top column 6 and the inter-column 7 of the stope. With the increase of the mining area, the stope roof falls naturally, and the ground pressure is managed by using the natural caving of the stope roof.

The specific steps of the novel mining method of the gently inclined thin-middle-thick ore body of the present invention are as follows:

1. In the stable surrounding rock area of the footwall of the ore body, excavate a segmented transport roadway 3 along the ore body direction. The width × height of the roadway section is 3.2m×3.4m. The roadway is supported by prestressed bolts, the bolts are 2.4m long, 18mm in diameter, the support mesh is 1.5m×1.5m, and the applied prestress is greater than 100KN.

2. The vertical segmental transportation roadway 3 is excavated into the mine-exit road 4, the distance between the mine-exit road 4 is 12-15m, and the roadway section is 3.2m×3.4m. Adopt the same support method as the segmental transportation roadway 3 to support the ore-exiting approach 4; use grouting long anchor cables at the T-shaped fork between the segmental transportation roadway 3 and the ore-exiting approach 4, and the anchor cables The length is 6.0m, the mesh size is 3.0m×3.0m, and the grouting water-cement ratio is 0.35-0.4.

3. When the ore exit route 4 is excavated to the footwall of the ore body at 3-5m, a rock drilling road 5 is arranged perpendicular to the ore exit route 4. There are four ore-exiting approaches 4, which are convenient for ore-exiting. The rock drilling roadway 5 is supported by the same support method as the segmented transportation roadway 3 .

4. Each mining access road 4 is regarded as a stope. Space columns 7 are reserved between adjacent stopes, and top columns 6 are reserved between the upper and lower sections of the stope to achieve ground pressure control and waste rock prevention. purpose of mixing. The mining sequence is from the middle of the segment to both ends.

5. Use fan-shaped medium and deep hole 10 blasting for ore falling. Drilling rigs are used to efficiently drill holes with a hole diameter of 76mm, a hole bottom distance of 2.0m, and a row distance of 2.0m. Firstly, the stope area 1 is mined by the caving method, the cutting cross-cutting 9 and the cutting raised well 8 are constructed in the rock drilling road 5, several rows of upward holes are constructed in the cutting cross-cutting 9, and the cutting raised well 8 is used as the free surface blasting Finally, a cutting groove is formed to provide a free surface for blasting. The empty area 12 is formed after the blasting in the stope area 1 to provide a free surface for the blasting in the stope area 2 .

6. The stope area 2 is mined, and fan-shaped medium-deep holes 10 are arranged perpendicular to the ore body inclination, as shown in Figure 4. The blast hole is charged in sections, and the charge part is from the boundary of the ore body footwall to the bottom of the hole, as shown in Figure 4. 4 In the part of the solid line, the empty area 12 formed by mining in the stope area 1 is used as the free surface to blast row by row, and the ore in the stope area 2 is thrown into the empty area 12 by explosive force.

7. The ore is discharged in time after each row of blast holes is blasted, providing a free surface for the next row of blasting. Use a scraper to enter the rock drilling road 5 through the ore-exit approach 4 and the adjacent ore-exit approach 4 to extract ore. In the late stage of mining, part of the ore in the rock drilling road 5 will eventually form a cone-shaped ore pile, which cannot be shoveled out, and is recovered in the next section by using the small ore chute 11.

8. After the sectional mining is completed, excavate the ore chute 11 in the sectional rock drilling 5 upwardly in the sectional transport roadway 3, and reclaim the residual ore heap in the sectional rock drilling 5 through the chute 11.

Compared with the existing gently inclined ore body mining method, the present invention has the following characteristics and advantages:

(1) This mining method combines the non-pillar segmental caving method and the explosive force transportation method, overcomes the shortcomings of a single mining method, and realizes the complementary advantages of different mining methods. Provided new ideas.

(2) The roadway engineering of this method is arranged in the stable surrounding rock outside the ore body, which reduces the difficulty and workload of support; workers do not need to be directly exposed to work in the stope, and the work is safer.

(3) The mining and cutting process of this method is simple, easy to construct, the amount of mining and cutting work is small, and the mining cost is low; the ore is thrown into the empty area 12 by explosive force handling, and the ore exit road 4 is out of the mine and the rock drilling road 5 The ore is extracted from the end, and the ore in the upper stage is recovered after digging the small shaft 11 in the middle section of back mining, which improves the difficult problem of ore extraction in the gently inclined ore body.

(4) The entire mining process can fully realize the mechanized operation of trackless equipment, and the labor productivity is high.

Description of drawings

Figure 1 is a schematic diagram of the mining of gently inclined ore bodies in different regions. The green area is the stope area 1, and the blue area is the stope area 2.

Fig. 2 is the front view I-I of novel mining method design of the present invention.

Fig. 3 is a sectional view of the main view II-II.

Figure 4 is a cross-sectional view of the main view III-III, showing the layout of blastholes in the explosive force transport mining method.

in the picture

1 stope area 8 cutting patio

2 Stope area 9 Cutting lane

3 Sectional transportation roadway 10 Medium and deep holes

4 Mine exit route 11 Mine slip shaft

5 Drilling Road 12 Empty Area

6 Pillars 13 Ore

7 Columns 14 Scraper

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Due to the influence of folds, the occurrence of a certain copper ore body is complex and changeable. The ore body at the syncline axis is relatively gentle, and it continues to rise from the syncline axis to the two wings. The average dip angle of the syncline axis is 15°. The average body thickness is 6m. The roof of the ore body is argillaceous slate, which has good stability. When the stope span is not large, it can form an open field condition; the ore-bearing layer is dolomitic schist, and the structural plane of this rock mass is well developed, so local collapse and flaking are prone to occur , and easily weathered and cemented; the schist ore rocks in the transition zone of the ore body floor are relatively broken and have poor stability; the conglomerate and argillaceous quartzite in the chassis are relatively stable. To sum up, the occurrence of this ore body is changeable, the dip angle of the ore body is relatively slow, the rocks of the ore seam and the transitional zone of the footwall are poorly fixed, and it is difficult to arrange the roadway inside the ore body; the thickness of the ore body is not large, and the mining method with bottom structure is used When the mining-cutting ratio is too large, the cost is high; when the non-pillar layered caving method is used, the mining-cutting project is arranged in the stable surrounding rock of the footwall of the ore body, and the mining dilution rate is high. Use novel mining method of the present invention to mine this ore body, in conjunction with Fig. 1, Fig. 2, Fig. 3, Fig. 4 illustrate specific implementation, as follows:

1. The stope is arranged along the direction of the ore body, and the mining sequence is from the middle of the segment to both ends. Excavate segmented transport roadway 3 in the stable surrounding rock area of the footwall of the ore body, and excavate segmented transport roadway 3 vertically into ore-exiting route 4. The length of ore-exiting route 4 is 25m long and the spacing is 15m. The rock drilling road 5 is arranged at a position 3m away from the footwall of the ore body. The width × height of the roadway section is 3.2m × 3.4m.

2. Construct a cutting lane 9 and a cutting patio 8 in the rock drilling road 5, construct several rows of upward holes in the cutting lane 9, form a cutting groove after blasting with the cutting patio 8 as a free surface, and provide a free surface for blasting.

3. Use prestressed anchor rods to support the roadway. The prestressed anchor rod is 2.4m long, 18mm in diameter, and the support network is 1.5m×1.5m. The applied prestress is greater than 100KN. The exposed area of the top plate of the T-shaped fork at the intersection of the segmental transportation roadway 3 and the mine exit road 4 is relatively large, and the grouting long anchor cable is added for support. The anchor cable is 6.0m long and the mesh is 3.0m×3.0m. If the surrounding rock in some areas is broken or becomes loose due to the impact of blasting shock waves, reinforcement support shall be adopted, steel mesh shall be added, and wooden support shall be used if necessary.

4. Each mining approach 4 is regarded as a stope, a 1m column 7 is reserved between adjacent stopes, and a 3m top column 6 is reserved between the upper and lower sections of the stope.

5. First stope stope area 1. Use a rock drilling rig to drill holes with a hole diameter of 76mm, a hole bottom distance of 2.0m, a row distance of 2.0m, and a side hole angle of not less than 45° (ore natural repose angle of 38°). ANFO porous granular ammonium oil explosives are used, the fan-shaped blast hole is charged for the entire length, and the bottom of the nonel hole is detonated. Each time 1 to 2 rows are blasted. After each blast, a scraper is used to pass through the ore outlet 4 and adjacent outlet The mine access road 4 enters the rock drilling road 5 and goes out of the mine.

6. After the stope area 1 is recovered, the stope area 2 is mined, and the drilling rig is used to drill holes, and the fan-shaped medium-deep holes 10 are arranged perpendicular to the ore body inclination, as shown in Figure 4. The depth of the blast hole depends on the situation. The longest hole depth is 12.88m, the hole diameter is 76mm, the hole bottom distance is 2.0m, and the row distance is 2.0m. The blast hole is charged in sections, the solid line segment of the blast hole in the figure is the charge segment, and the dotted line segment is the non-charge segment. The charge part is from the boundary of the footwall of the ore body to the bottom of the hole, as shown in the solid line in Figure 4, the empty area 12 formed by the stope area 1 is used as the free surface to blast row by row, and the ore in the area 22 is thrown to the bottom of the hole by explosive force. In empty zone 12. After back mining, enter the rock drilling road 5 to extract the ore through the ore-exiting approach 4 and the adjacent ore-exiting approach 4.

7. In the later stage of mining, part of the ore in the rock drilling road 5 will eventually form a conical ore heap, which cannot be shoveled out. After the next segment of mining is completed, the mine chute 11 is used to recover in the next segment.

The ore body with a thickness of 6m and an inclination angle of 15° is mined by adopting the new mining method described in this invention. The section height is 8m, the cutting ratio is 10.4m/kt, the ore dilution rate is 11.49%, and the ore recovery rate is 87% %.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit In the present invention, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (7)

1. a kind of mining method of gently inclined thin-middle thick ore body, it is characterized in that, described mining method is when mining gently inclined thin-middle thick ore body, the ore body in a stope is divided into two stopes Areas (1) and (2) are mined step by step; Firstly, the stope area (1) is mined by using the segmental caving method without pillars, and the ore body is directly caving in a single segment by using medium and deep hole blastholes; a certain empty area is formed as the stope area (2 ) the free face of mining; Then, the stope area (2) is mined using the explosive force transport mining method, and the fan-shaped medium and deep hole blastholes are arranged perpendicular to the ore body inclination. The medium and deep hole blastholes are charged in sections, and the charge part is the ore body footwall. From the boundary to the bottom of the hole, the empty area formed by the stope area (1) is used as the free surface to blast row by row, and the ore in the stope area (2) is thrown into the empty area by explosive force; After the stope mining is completed, the cone-shaped ore heap formed by the part of the ore in the stope rock drilling road is recovered through the small ore slide shaft dug upward in the segmented rock drilling road in the segmented transportation roadway. 2. mining method according to claim 1, is characterized in that, the concrete steps of described mining method are as follows: 1) In the stable surrounding rock area of the footwall of the ore body, excavate a segmental transport roadway (3) along the ore body direction, and the roadway is supported by prestressed bolts; 2) Excavating the ore-exiting road (4) in the vertical section transportation roadway (3), adopting the same support method as the section transportation roadway (3) to support the ore-exiting road (4); The T-shaped fork between the roadway (3) and the mine exit (4) is supported by grouting long anchor cables; 3) When the ore-exiting route (4) is excavated to the footwall of the ore body at 3-5m, a rock drill (5) is arranged perpendicular to the ore-exiting route (4), and the rock-drilling road (5) connects each ore-exiting Road (4); adopt the same support method as the segmented transportation roadway (3) to support the rock drilling road (5); 4) Each ore-out approach (4) is regarded as a stope, and space columns (7) are reserved between adjacent stopes, and top columns (6) are reserved between the upper and lower sections of the stope to achieve control Ground pressure, preventing waste rock from mixing in; the mining sequence is from the middle of the segment to both ends; 5) Use fan-shaped medium-deep hole (10) blasting to carry out ore falling, and use rock drilling rigs to drill holes; first, use the caving method to mine the stope area (1), and construct cutting cross roads in the rock drilling road (5) (9) and the cutting patio (8), several rows of upward holes are constructed in the cutting lane (9), and the cutting slot (8) is used as the free surface blasting to form a cutting groove to provide a free surface for blasting; the stope area ( 1) An empty area (12) is formed after blasting out of the mine to provide a free surface for blasting in the stope area (2); 6) The stope area (2) is mined, and the fan-shaped medium-deep holes (10) are arranged perpendicular to the ore body inclination. The medium-deep holes (10) are charged in sections, and the charge part is from the boundary of the footwall of the ore body to the bottom of the hole. Taking the empty area (12) formed by mining in the stope area (1) as the free surface to blast row by row, and throw the ore in the stope area (2) into the empty area (12) by using explosive force; 7) After blasting each row of blast holes, the ore is discharged in time to provide a free surface for the next row of blasting, and the scraper is used to enter the rock drilling road (5) through the ore discharge route (4) and the adjacent ore discharge route (4) Ore extraction; in the later stage of ore extraction, some ore in the rock drilling road (5) will eventually form a conical ore pile, which will be recovered in the next section by using the small ore chute (11); 8) After the sectional mining is completed, excavate the sectional rock drilling passage (5) in the sectional transportation roadway (3) upwards and drill the small ore slipping shaft (11), and reclaim the upper sectional rock drilling (5) through the small ore slipping shaft (11) ) remaining ore piles. 3. The mining method according to claim 2, characterized in that, the sectioned transportation roadway (3), the ore-out approach (4) and the rock drilling road (5) are arranged in the stable surrounding rock of the footwall of the ore body. In the area, the distance between the mine access roads (4) is 12-15m, and the rock drilling road (5) connects each mine exit road (4); the roadway section width × height is 3.2m × 3.4m; The prestressed bolt support adopted, the bolt length is 2.4m, the diameter is 18mm, the support mesh is 1.5m×1.5m, and the applied prestress is greater than 100KN; 3.2m×3.4m; the anchor cable supported by the grouting long anchor cable used at the T-shaped fork of the segmental transportation roadway (3) and the ore approach (4) is 6.0m long, and the mesh is 3.0m×3.0m. The grouting water-cement ratio is 0.35-0.4. 4. The mining method according to claim 3, characterized in that, in the step (5), the section of the cutting patio (8) is 2.0m×2.0m, which is a vertical or inclined patio; cutting the horizontal lane (9) is to The mine-exit approach (4) extends forward. 5. mining method according to claim 4 is characterized in that, the aperture 76mm of the fan-shaped deep hole (10) used in described step (5) and step (6), hole bottom distance 2.0m, row distance 2.0m m, the hole depth shall not exceed 30m. 6. The mining method according to claim 5, characterized in that, the wind flow direction of the stope ventilation is as follows: the fresh air passes through the sectioned transport roadway (3), the ore-out approach (4), and the rock drilling road (5) , After washing the working face, it is drawn out through the air return patio; the single-head working face is blown/extracted by means of a blower to ensure the quality of the working air. 7. mining method according to claim 6 is characterized in that, in the initial stage of stope mining, utilize stope top column (6) and inter-column (7) to support stope roof, along with the increase of stope area , the roof of the stope falls naturally, and the ground pressure is managed by using the natural caving of the roof of the stope.