CN111927460A - Thick ore body mining method - Google Patents
Thick ore body mining method Download PDFInfo
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- CN111927460A CN111927460A CN202010826317.6A CN202010826317A CN111927460A CN 111927460 A CN111927460 A CN 111927460A CN 202010826317 A CN202010826317 A CN 202010826317A CN 111927460 A CN111927460 A CN 111927460A
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- 238000005065 mining Methods 0.000 title claims abstract description 46
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000005520 cutting process Methods 0.000 claims abstract description 72
- 210000003462 vein Anatomy 0.000 claims description 10
- 238000005422 blasting Methods 0.000 claims description 5
- 238000003825 pressing Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 abstract description 4
- 238000005553 drilling Methods 0.000 description 9
- 239000011435 rock Substances 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
- 238000000605 extraction Methods 0.000 description 3
- 238000009423 ventilation Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 238000013316 zoning Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C41/00—Methods of underground or surface mining; Layouts therefor
- E21C41/16—Methods of underground mining; Layouts therefor
- E21C41/22—Methods of underground mining; Layouts therefor for ores, e.g. mining placers
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/14—Layout of tunnels or galleries; Constructional features of tunnels or galleries, not otherwise provided for, e.g. portals, day-light attenuation at tunnel openings
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F13/00—Transport specially adapted to underground conditions
- E21F13/02—Transport of mined mineral in galleries
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
- E21F17/18—Special adaptations of signalling or alarm devices
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Mechanical Engineering (AREA)
- Remote Sensing (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
Abstract
The invention relates to the technical field of mining methods, in particular to a thick and large ore body mining method. The single thick and large ore body is manually divided into two independent subareas, the original ore blocks are doubled, the yield is favorably improved, the spare ore blocks are added, and the production coordination is more flexible and stable. The method comprises the following steps: a first cutting roadway and a second cutting roadway are arranged on a vertical access of the thick and large ore body, and one thick and large ore body is divided into two subareas.
Description
Technical Field
The invention relates to the technical field of mining methods, in particular to a thick and large ore body mining method.
Background
At present, 15m to 40m is generally specified as a thick ore body, and more than 40m is specified as an extremely thick ore body. In the mining operation, the sublevel height is 20m, the middle section height is 60m, ore bodies with the thickness more than 30m adopt a sill pillar-free sublevel caving method arranged in the vertical direction, and ore bodies with the thickness less than 30m adopt a sublevel caving method arranged along the direction.
The existing mining process of thick and large ore bodies has the following defects.
Firstly, the ore removal efficiency is low.
For example: the rough road iron ore is transported by a forklift loading mode, if a rock drilling access is too long, the time for the forklift to go and load the ore is increased, the forklift table effect is greatly reduced, and the improvement of the whole mine yield is influenced.
Secondly, the ventilation effect is poor.
Because the stoping operation is carried out in the single-head roadway, although the ventilating pedestrian patios of the mining area are uniformly distributed in each stope, the condition of safe operation can be met only by blowing off blasting smoke for a large amount of time after blasting of each drilling approach even if forced ventilation is adopted due to the long ventilation distance. And because the trackless equipment such as forklift truck discharges tail gas in the overlength of operation, then the requirement to the air volume is higher.
And thirdly, the formation of the reserve mining amount lags.
In general mining, a single rock drilling access is more than 100m, the medium-length hole drilling time of the whole stope is greatly prolonged, about three months is still needed until a mining condition is really met after a mining preparation project is completed, and the problem of shortage of ore removal places is caused.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a thick and large ore body mining method.
In order to achieve the purpose, the invention adopts the following technical scheme that the method comprises the following steps: a first cutting roadway and a second cutting roadway are arranged on a vertical access of the thick and large ore body, and one thick and large ore body is divided into two subareas.
Further, simultaneously, respectively arrange a haulage roadway in the hanging wall and the footwall of ore body, two haulage roadways in: one transport roadway is arranged outside the vein, the other transport roadway is arranged in the vein, and the two transport roadways form an annular transport mode.
Further, in two haulage roadways: the lower plate transportation roadway is arranged outside the vein, and the upper plate transportation roadway is arranged in the vein.
Further, the second cutting roadway is parallel to the first cutting roadway.
Furthermore, the cutting lane distance between the first cutting lane and the second cutting lane is 9 m.
Further, the first cutting roadway and the second cutting roadway are arranged on two sides of the center of the vertical access.
Furthermore, a cutting well is arranged between the first cutting roadway and the second cutting roadway, a connecting line is formed between the first cutting roadway and the second cutting roadway, and the center of the cutting well is located at the center of the connecting line.
Furthermore, the distance between the cutting well and the first cutting roadway or the second cutting roadway is as follows:
when the ore drawing height is less than 18m, the distance between the cut well and the cutting roadway is less than (W' + a-1.8)/(0.6 x 2).
When the ore drawing height is more than 18m, the distance between the cut well and the cutting roadway is less than (W' + a-1.8)/(0.6 x 2).
Wherein W' represents the approximate width of an ore drawing ellipsoid; a represents the minimum draw width, typically 1.8 m.
The theory of the ore drawing ellipsoid is that the ore is continuously discharged from the ore drawing opening, and the ore on the ore is sequentially supplemented to form a lengthened ellipsoid similar to rotation, which is called the ore drawing ellipsoid. To eliminate the variable factors of different tap hole sizes, the theoretical width W' of the ore drawing ellipsoid can be determined using analytical and modeling data, field tests and observations in sill pillar free sublevel caving operations, assuming that the ore passes through the smallest tap hole.
Furthermore, the fan-shaped holes are arranged when the tunnel is blasted and cut and are used for recovering ore bodies between the two cutting tunnels.
Furthermore, the first cutting roadway and the second cutting roadway divide the ore body into two independent subareas, independent operation is carried out, and the stoping sequence is not influenced mutually.
Furthermore, the positions of the lower-layer double-cutting roadway are reasonably arranged, so that the safe distance of the upper layer and the lower layer in cooperation with mining is kept.
Furthermore, after the zonal extraction of the upper layer and the lower layer is started, the lower layer and the lower layer can lag the upper layer and the lower layer to cut 20m of the roadway for extraction, and the ore pressing problem is avoided by carrying out zonal transportation.
Compared with the prior art, the invention has the beneficial effects.
The invention increases the working face of simultaneous mining. The single thick and large ore body is manually divided into two independent subareas, the original ore blocks are doubled, the yield is favorably improved, the spare mining ore blocks are added, and the production coordination is more flexible and stable.
Drawings
The invention is further described with reference to the following figures and detailed description. The scope of the invention is not limited to the following expressions.
Fig. 1 is a schematic view of a dual cutting roadway layout of the present invention.
Fig. 2 is a schematic view of a haulage roadway layout.
Fig. 3 is a cut tunnel blast hole arrangement diagram.
Fig. 4 is a diagram of arrangement of blast holes of a rock drilling roadway.
Detailed Description
The thick ore body in the invention means that the average thickness of the ore body is 100m-160 m.
As shown in figure 1, the invention adopts a zoning mining scheme aiming at the problem of thick and large ore bodies. A cutting roadway is arranged at the middle point of the vertical access way, a cutting roadway parallel to the original cutting roadway is added, the distance between the cutting roadways is 9m, and a cutting well is arranged in the middle of the two cutting roadways.
Meanwhile, a transport roadway is respectively arranged on the upper and lower trays of the ore body, the lower tray transport roadway is arranged outside the vein, and the upper tray transport roadway is arranged in the vein to form an annular transport form. The arrangement of the haulage roadway is shown in fig. 2.
The two cutting roadways thoroughly divide the ore body into two independent subareas, do not need simultaneous operation, and can not influence each other in the mining sequence.
The invention can carry out upper and lower layering collaborative mining in advance. The lower-layer double-cutting roadway position is reasonably arranged, and the safe distance of upper-layer and lower-layer collaborative mining can be met. After the zonal extraction of the upper layer and the lower plate is started, the lower layer and the lower plate can lag the upper layer and the lower plate to cut 20m of the roadway for mining, and the ore pressing problem is avoided by carrying out zonal transportation.
The arrangement form of the partitioned double-cutting lane can be combined with a sill pillar-free sublevel caving method to mine thick and large ore bodies, a good effect is achieved in the mining process of 290-kiloton/a ground mining projects of the rough road and iron ores, and efficient and stable production is guaranteed on the premise of not increasing a large amount of engineering quantity.
The invention increases the working face of simultaneous mining. The single thick and large ore body is manually divided into two independent subareas, the original ore blocks are doubled, the yield is favorably improved, the spare mining ore blocks are added, and the production coordination is more flexible and stable. The arrangement of the annular transportation lane increases ore loading places, avoids ore removal places and equipment congestion, indirectly reduces the transportation time of trackless transportation equipment, and increases the working efficiency of the equipment.
The invention can reduce the mine-holding distance of the forklift. The partition arrangement reduces half of a rock drilling approach, mining is carried out from the middle part of an ore body to the upper and lower trays in two directions, the distance from the ore end of a forklift to loading is correspondingly reduced, and the ore loading efficiency is improved.
The invention can form the prepared mining block in advance. The traditional single-partition single-cutting roadway stoping arrangement mode needs to carry out stoping operation after the construction of the whole rock drilling access medium-length hole is completed, and the construction time is too long for thick and large ore bodies, so that the formation of a standby mining block is influenced.
Specifically, during construction, the lower wall cutting lane is arranged in the west of the upper layered cutting lane, and after the middle section lower wall ore body is guaranteed to be stoped for a certain distance, collaborative mining can be carried out, so that the ore pressing problem existing in the original optimization scheme is avoided.
As shown in fig. 3 and 4, the cutting well is located between the two cutting roadways, so that the fan-shaped holes can be arranged during blasting cutting of the roadways, and ore bodies in the middle of the cutting roadways at intervals of 9m are recovered. Cutting and drilling are carried out by adopting an YGZ-90 type rock drill to drill fan-shaped parallel blast holes in a cutting roadway, stoping and drilling are carried out by adopting a YGZ-90 type guide rail type independent rotary rock drill matched with a TJ25 type disc type drill rig to drill fan-shaped blast holes in a stoping route, 9-11 holes in each row are drilled, and the total length is 120-130 m. The aperture of the cutting lane is 60 mm, the row spacing is 1.1 m, and the bottom spacing is 1.1 to 1.3 m. The diameter of the vein-through hole is 60 mm, the row spacing is 1.7 m, and the bottom spacing is 1.7 to 2.0 m. Cutting the raise height of 19m, and reserving 1m to protect the ore pillar.
The invention adjusts the traditional end retreat mining sequence to mining from the middle double-cutting lane to the upper and lower disk directions, avoids the situations of insufficient blasting space, increased loss and dilution and the like, and is extremely suitable for mines with large ore body thickness and unbalanced descending speed of upper and lower disk mining to rapidly improve the productivity. The method solves the problem of ore layering in a very short time, releases the capacity on the premise of not greatly increasing the engineering quantity, and cannot influence the mining of the disk zoning in the future.
The arrangement of the annular transportation lane increases ore loading places, avoids ore removal places and equipment congestion, indirectly reduces the transportation time of trackless transportation equipment, and increases the working efficiency of the equipment.
It should be understood that the detailed description of the present invention is only for illustrating the present invention and is not limited by the technical solutions described in the embodiments of the present invention, and those skilled in the art should understand that the present invention can be modified or substituted equally to achieve the same technical effects; as long as the use requirements are met, the method is within the protection scope of the invention.
Claims (10)
1. A thick ore body mining method is characterized by comprising the following steps:
a first cutting roadway and a second cutting roadway are arranged on a vertical access of the thick and large ore body, and one thick and large ore body is divided into two subareas.
2. A method of mining a thick and large ore body according to claim 1, characterized in that: simultaneously, respectively arrange a haulage roadway in the hanging wall and the lower wall of ore body, in two haulage roadways: one transport roadway is arranged outside the vein, the other transport roadway is arranged in the vein, and the two transport roadways form an annular transport mode.
3. A method of mining a thick ore body according to claim 3, characterized in that: in two haulage roadways: the lower plate transportation roadway is arranged outside the vein, and the upper plate transportation roadway is arranged in the vein.
4. A method of mining a thick and large ore body according to claim 1, characterized in that: the second cutting roadway is parallel to the first cutting roadway.
5. A method of mining a thick and large ore body according to claim 1, characterized in that: the distance between the first cutting roadway and the second cutting roadway is 9 m.
6. A method of mining a thick and large ore body according to claim 1, characterized in that: the first cutting roadway and the second cutting roadway are arranged on two sides of the center of the vertical access way.
7. A method of mining a thick and large ore body according to claim 1, characterized in that: a cutting well is arranged between the first cutting roadway and the second cutting roadway, a connecting line is formed between the first cutting roadway and the second cutting roadway, and the center of the cutting well is located at the center of the connecting line.
8. A method of mining a thick and large ore body according to claim 7, characterized in that: the distance between the cutting well and the first cutting roadway or the second cutting roadway is as follows:
when the ore drawing height is less than 18m, the distance between the cut well and the cutting roadway is less than (W' + a-1.8)/(0.6 x 2);
when the ore drawing height is more than 18m, the distance between the cut well and the cutting roadway is less than (W' + a-1.8)/(0.6 x 2);
wherein W' represents the approximate width of an ore drawing ellipsoid; a represents the minimum draw width, typically 1.8 m.
9. A method of mining a thick and large ore body according to claim 1, characterized in that: and the fan-shaped holes are arranged during blasting and cutting the laneway and are used for recovering ore bodies between the two cutting laneways.
10. A method of mining a thick and large ore body according to claim 1, characterized in that: the first cutting roadway and the second cutting roadway divide an ore body into two independent subareas, the independent operation is carried out, and the stoping sequence is not influenced mutually; the positions of the lower-layer double-cutting roadway are reasonably arranged, so that the safety distance of the upper-layer and lower-layer collaborative mining is kept; after the upper-layer lower plate partitioned stoping is started, the lower-layer lower plate can lag behind the upper-layer lower plate cut roadway for mining at a certain distance, and the ore pressing problem is avoided by means of layered separate transportation.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010826317.6A CN111927460B (en) | 2020-08-17 | 2020-08-17 | Thick ore body mining method |
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| CN202010826317.6A CN111927460B (en) | 2020-08-17 | 2020-08-17 | Thick ore body mining method |
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| CN111927460B CN111927460B (en) | 2021-04-27 |
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2020
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