CN214145491U - Mine left-over pillar extraction system - Google Patents

Mine left-over pillar extraction system Download PDF

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Publication number
CN214145491U
CN214145491U CN202120066441.7U CN202120066441U CN214145491U CN 214145491 U CN214145491 U CN 214145491U CN 202120066441 U CN202120066441 U CN 202120066441U CN 214145491 U CN214145491 U CN 214145491U
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mine
pillar
support leg
carryover
supporting
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Inventor
吴维成
陈广宁
马印禹
李红旗
吴宝林
高松涛
刘兴宇
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Xilingol League Shanjin Aer Hada Mining Co ltd
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Xilingol League Shanjin Aer Hada Mining Co ltd
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Abstract

The utility model relates to a mine is left over pillar extraction system relates to mining technical field, and it is big to have solved current mine pillar leaveed volume, has hindered the technical problem of mine production system structure adjustment and continuation development. The utility model discloses a mine remains pillar recovery system, including drilling blasting unit, ventilation unit, supporting device and ore removal device, supporting device includes interconnect's support leg and back timber, all be equipped with the reinforcement lacing wire between support leg and the back timber, the support leg top is equipped with U type groove, the back timber is arranged in U type groove and is welded; and a fixed rib plate is further arranged between the support leg and the top beam, and the supporting device can be installed in a stoping access. The utility model discloses a mine is left over post extraction system has solved the current glued body of no reinforced cement tailing and has followed the back extraction safety problem of fore-set down, has retrieved the resource safely high-efficiently economically.

Description

Mine left-over pillar extraction system
Technical Field
The utility model belongs to the technical field of the mining technique and specifically relates to a mine is left over ore pillar extraction system.
Background
Many mines usually undergo the transition from open stope mining to filling mining, and after many years of mining, the remaining pillar ore amount accounts for a great proportion of the geological reserve, and part of the ore has relatively high grade and high value. Along with the continuous promotion of mine production capacity, the mining is to deep extension and production system's structural adjustment, and a large amount of high value ore pillars that the exploitation was left over for many years influence mine production system structural adjustment and sustainable development, for guaranteeing mine steady production and sustainable development, the ore pillars that upper portion middle section was left over need retrieve as early as possible.
In addition, the inside top sill post of mine after many years of exploitation is rock mass stress concentration district, poor stability, and the final direct roof of stope is artificial false top (the artificial false bottom of upper middle section stope) usually, and the stability of stope mainly relies on the bearing strength of artificial false top, and the false top is crooked under horizontal stress and vertical stress effect, and the fracture destruction takes place when stress reaches the intensity critical value, leads to leaving over the recovery process of ore pillar and has very big difficulty and potential safety hazard.
Therefore, how to safely and efficiently recycle the part of resources and improve the resource utilization rate is a problem which needs to be solved urgently in the mining process.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a mine is left over ore pillar recovery system has solved that current mine ore pillar remains big, has hindered the technical problem of mine production system structure adjustment and continuation development.
The technical scheme of the utility model is that: a mining system for mine left-behind pillars comprises a drilling blasting device, a ventilating device, a supporting device, a mine removal device and a filling device, wherein the supporting device comprises a support leg and a top beam which are connected with each other, reinforcing tie bars are arranged between the support leg and the top beam, a U-shaped groove is formed in the top end of the support leg, and the top beam is arranged in the U-shaped groove and welded; and a fixed rib plate is further arranged between the support leg and the top beam, and the supporting device can be installed in a stoping access.
Preferably: the supporting device is fixed on the fixed round steel of the side wall or the top wall of the working face of the stoping access way through a connecting piece.
Preferably: the support legs and the top beam are made of I-shaped steel.
Preferably: the support leg is further provided with a fixing base plate, and two sides of the support leg are provided with wood plates.
Preferably: the top beam is provided with a wood board and is plugged and connected with the top through a wood pile formed by arranging a plurality of round wood in a shape like a Chinese character 'jing'.
Preferably: the ore removal device is a scraper, and the stoped ore is conveyed to the ore pass outside the stope through the scraper.
Preferably: and the rock drilling blasting device is used for drilling by an air leg type rock drill.
Preferably: the ventilation device comprises a press-in type fan and a draw-out type fan.
Preferably: the mining system for the left pillar of the mine further comprises a filling device.
Preferably: the filling device comprises a bulk ore cleaning device, a filling pipeline frame, a water draining cage and a steel mesh plate wall capable of closing an inlet road junction.
The utility model has the advantages that: the utility model discloses a mine is left over post extraction system has solved the current glued body of no reinforced cement tailing and has followed the back extraction safety problem of fore-set down, has retrieved the resource safely high-efficiently economically. Other advantageous effects of the preferred embodiments of the present invention are explained in detail below.
Drawings
Figure 1 is a schematic structural view of a frame of a retaining and protecting device according to the present embodiment;
FIG. 2 is a schematic view of the structure of the bracket leg in the present embodiment;
FIG. 3 is an enlarged view of portion A of FIG. 2;
FIG. 4 is a schematic view of the construction of the end of the header in this embodiment;
fig. 5 is a schematic structural view of the rectangular supporting device in this embodiment;
FIG. 6 is an enlarged view of portion B of FIG. 5;
FIG. 7 is a schematic structural view of the ladder type supporting device in this embodiment
In the figure: 1. a support leg; 2. a top beam; 3. bracing among the bracket legs; 4. stretching a rib between the top beams; 5. an anti-sink backing plate; 6. fixing the rib plate; 7. wood cribs; 8. a wood board; 9. extracting a route profile; 10. and fixing the round steel.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
Examples
The embodiment provides a mining system for a mine left-behind pillar, which comprises a drilling blasting device, a ventilation device, a supporting device, a ore removal device and a filling device, wherein the supporting device comprises a support leg and a top beam which are connected with each other, and a brace between the support legs is arranged between a plurality of parallel support legs; a tie bar between the top beams is arranged between the parallel top beams, a U-shaped groove is arranged at the top end of the bracket leg, and the top beams are arranged in the U-shaped groove and welded; the support device comprises a support leg, a top beam, a tie bar between the support leg and the top beam, a support device and a support device, wherein a fixed rib plate is further arranged between the support leg and the top beam, the support device can be installed in a stoping access way, and the support leg, the top beam, the tie bar between the support legs and the tie bar between the top beams form a framework of the support device.
The applicable conditions of the supporting device of the embodiment are as follows: and a metal bracket supporting mode is adopted by the extraction top column under the reinforcement-free tailing cemented body.
As shown in fig. 1 to 7, the support legs and the top beam in the supporting device are all i-steel. The support legs are also provided with fixed backing plates, and two sides of each support leg are provided with back solid boards. The top beam is also provided with a wood board and is plugged and connected with the top through a wood pile with a plurality of round wood arranged in a shape like a Chinese character 'jing'.
The concrete technical parameters of the supporting device in this embodiment are as follows: firstly, both a support leg and a top beam are made of 16# I-steel, and both the support leg and a top beam lacing wire are reinforced and connected by 14# steel channels; at least three lacing wires are arranged between the support legs and between the top beams respectively (the spacing between the lacing wires is 800-1000 mm); placing the top beam in a U-shaped groove of the bracket leg and welding; welding a fixed ribbed plate of an equilateral triangle between the top beam and the support leg, wherein the fixed ribbed plate is a steel plate with delta being more than or equal to 3 mm; fourthly, fixing a base plate on the anti-sinking metal bracket leg, wherein 16# channel steel is adopted, and the length is not less than 0.25 m; each connecting component adopts continuous welding, and the height of a welding seam is more than or equal to 3 mm; sixthly, the top of the supporting device is filled with a wood board and a 'well' -shaped wood pile to be connected with the top. Seventhly, locally ultra-wide access is realized, and two sides of the supporting device are backed with wood plates. Eighthly, the space-to-ceiling distance between the supporting device and the face of the stoping and advancing road cannot exceed 2m, when the supporting device is installed, a 7655 or YT28 type rock drill is adopted to respectively construct a group of fixed round steel holes in rock bodies on two sides of the advancing road, the fixed round steel with diameter of 40mm is installed, I-shaped steel support legs are erected, I-shaped steel is welded on the fixed round steel, and top beams are welded on the I-shaped steel.
As shown in fig. 5-7, the profile of the stoping route of the support device can be trapezoidal or rectangular according to actual needs.
The Alhada lead-zinc ore, called Alhada lead-zinc ore, from Alhada mining, is a union of the Siline Guo, undergoes a transition from open-stope mining to filling mining, and a large number of high-value ore pillars left over after years of mining affect the structural adjustment and sustainable development of a mine production system. The conditions and the steps for extracting the 728m middle section 7219 stope top column of the Alhada lead-zinc ore by using the mining remaining pillar extracting system are detailed as follows:
first, stope structure parameter
The geometry of the approach path. According to relevant research data of the safe thickness of the top plate of the stoping top pillar by the approach method, when the safe thickness of the top plate (the thickness of a protective layer of the top pillar) reaches 3m, the length of an approach arranged along the trend is preferably controlled within 35m, the approach width is preferably (2-3.5 m), the factors such as the thickness, the shape, the loss and dilution of the ore body of the top pillar of the test stope are comprehensively considered, and the approach width is determined to be 2.6m and the height is determined to be 2.6 m.
2) And the thickness of the safety protection layer of the top pillar. 1m of original rock ore pillar is reserved in a top pillar stope, the original rock ore pillar and an artificial false bottom of a reinforcement-free graded tailing cementing body with the thickness of 2m in a 7617 stope form a top pillar mining safety protection layer, and the total thickness of the protection layer is 3 m.
3) The extraction height and the route arrangement. The stoping height of the top pillar stope is 5.2m, two layers of stopes are adopted, the layering height is 2.6m, two routes are divided in each layer, the routes are arranged along the trend of an ore body, and the single-side route stoping length is 35 m.
Second, mining accurate cutting engineering
The mining method mainly comprises an extravenal slope ramp, a layered combined roadway, a cutting roadway, an extravenal draw shaft, a draw shaft combined roadway, a small filling well and the like, wherein the extravenal draw shaft of a top pillar stope still utilizes the extravenal smooth draw shaft of the original stope, the extravenal slope ramp is arranged along the central line of the top pillar stope and perpendicular to the trend of ore bodies, the 21-line transvenous lane at the middle section of 768m is connected with the layered combined roadway of the top pillars, the slope ramp has the gradient of 17.63 percent, the downhill construction is carried out, and the small filling well is arranged at two wings of the stope.
Third, preparation before stoping and construction sequence
(1) Preparation before stoping
1)7219 after the last layering of the stope, respectively constructing a small filling well on two wings of the ore body in the stope, penetrating through a drift penetrating through the upper middle section and the lower middle section of 768m, excavating and constructing the filling well by a common method, selecting a YSP-45 upward rock drill as a rock drilling device, wherein the depth of a blast hole is 1.4-1.8 m, conducting non-electric millisecond delay initiation, selecting a JK58-1NO4/5.5KW press-in type fan for local ventilation, wherein the air volume is 132 plus 210m3/min, and the full pressure is 1020 plus 1648 pa. Manually closing the off-road pedestrian drainage well in the original stope, carrying out top lifting on the extravenal draw shaft connecting lane and the draw shaft chamber of the original stope by using an 7655 or YT28 type rock drill, and manually erecting the extravenal draw shaft along the road until the extravenal draw shaft is horizontal to the bottom plate of the top column.
2) And (3) carrying out graded tailing filling on the goaf of the roof-contacted filling stope, and then carrying out graded tailing cemented filling for 0.8m, wherein the cemented body is required to be fully roof-contacted, and the cement-sand ratio of the cemented body is 1: 4.
3) After the goaf is connected with the roof and filled, an 7655 type or YT28 type gas-leg rock drill is used for digging an external slope way from the lower part of the 768-section to the level of the bottom plate of the top pillar, a layered lane and a cutting lane are constructed to control ore bodies, a draw shaft is constructed to connect the lane and pass through an external smooth pass draw shaft, and the preparation work before the top pillar is stoped is finished.
(2) Sequence of construction
1) And the stope is stoped layer by layer from bottom to top in the top pillar stope layer, and the upper plate and the lower plate of the intake pipe in the same layer are stoped one by one.
2) And (4) carrying out layered mining below a layer, and carrying out forward mining to two wings of the ore body by a cutting roadway.
3) The upper layers of the two layers adopt short-circuit stoping to reduce the exposed area of the safety protection layer of the top column and shorten the empty top time. Firstly, the ore body is pushed to one wing by the cutting lane, and after the route of one wing is finished and the mining is finished and the top filling is carried out, the ore body is pushed to the other wing by the cutting lane.
4) And the access is controlled to carry out 3 per thousand upward slope mining to two wings of the ore body by the cutting lane and is communicated with the small filling well in construction, so that the bottom plate of the small filling well is slightly higher than the top plate of the access, and the full roof connection of filling is facilitated. And then, carrying out backward expansion mining on the triangular ore bodies on the upper and lower walls until a mining boundary is designed.
(3) Main extraction process
1) And carrying out rock drilling blasting by using the rock drilling blasting device. The rock drilling and blasting device is an 7655 type or YT28 type air-leg rock drill for rock drilling, 2# rock powdery emulsion explosive is used, non-electric millisecond delay initiation is carried out, and delay intervals are 50-100 milliseconds, so that damage of blasting to a top column safety protection layer and an adjacent access cemented filling body is reduced. And simultaneously, a smooth blasting technology is adopted, the hole spacing of the light blasting holes is 0.6m, the thickness of the light blasting layer is 0.8m, the hole density coefficient m is 0.75, and the linear charge density q of the light blasting layer is 0.1-0.2 kg/m, so that the stress concentration of the access top plate is eliminated.
2) And ventilating the stope face by using a ventilating device. Adopts mixed local ventilation, adopts JK58-1NO4/5.5KW type fans, has air volume of 132-. Fresh air flows through a lower plate slope way of the stope and is sent to a working face by using a press-in fan, and dirty air is sent to an upper-middle section air return system of 768m by using a pull-out fan through the lower plate slope way of the stope.
3) And managing the top plate by using a supporting device.
A layered stoping access mainly adopts a pipe seam type anchor rod and steel belt combined support, two sides of the access support equipment use 7655 type or YT28 type air-leg rock drills, a top plate support equipment uses YSP-45 upward rock drills, the anchor rod specification phi 42mm multiplied by L1800mm, steel belts are two parallel phi 12mm steel bars, the distance between the steel bars is 50mm, the length is 1500mm, the anchor rod is manufactured by spot welding, the anchor rod tray specification is 150mm multiplied by 80mm, the anchor rod mesh is 1500m multiplied by 1500m, the anchor rod tray and the steel belt are arranged in a quincunx shape, the minimum included angle with a rock stratum is not less than 60 degrees, the steel belt row distance is 1500mm, and the anchor rod tray and the steel belt are required to be tightly attached to the edge surface.
In the two-layer stoping process, a YSP-45 upward rock drill is used for constructing a pilot hole (the diameter phi of the pilot hole is 38mm), the thickness of an original rock pillar reserved in a top pillar safety protection layer is controlled, and overtaking is not required. Meanwhile, considering various factors such as the non-uniformity of the thickness of the upper artificial false bottom cementing body, the limited false bottom bearing energy of the non-reinforced graded tailing cementing body and the like, the mine adopts an integral continuous metal support for supporting so as to enhance the bearing capacity of the safety protection layer of the top pillar and improve the stability of the safety protection layer.
The empty roof distance between the metal support and the working face of the stoping access way is not more than 2m, the metal support is processed and manufactured on site, the metal support legs and the top beam are made of 16# I-steel, the support legs and the top beam are reinforced and connected by 14# channel steel tie bars, the tie bar distance is 800-1000 mm, and round wood or a back plate is filled between the top of the support and a rock mass to be propped. A16 # channel steel fixing base plate is welded on the metal support leg to prevent sinking, and the length of the base plate is not less than 0.25 m. When the metal support is installed, a 7655 type or YT28 type air-leg rock drill is used for respectively drilling a group of fixed round steel holes in rock bodies on two sides, diameter 40mm round steel is installed, I-shaped steel support legs are erected, I-shaped steel is welded on the round steel, and top beams are welded on the I-shaped steel.
4) And (5) ore removal is carried out by using an ore removal device. And (3) carrying the ore to a downstream pass outside a stope vein by using a WJD-1 type electric scraper or an HLWJ-1.0 diesel scraper, and dragging the YFC0.7-6 type mine car to a 27-line main pass to unload by using a ZK3-6/250 type electric locomotive after ore drawing by using a 728m middle section vibrating hopper.
5) Filling by a filling device. And immediately cleaning scattered ores after the stoping of the access is finished, erecting a filling pipeline, installing a water drainage cage, constructing a steel mesh plate wall to close the access opening, and utilizing a small filling well to timely top-contact the access opening for filling. In order to fully contact the roof, after the primary filling is finished, supplementary filling is carried out at intervals of 24 hours; the upper plate inlet path is filled by using graded tailing cemented filling, the cement body sand-lime ratio is 1: 4, the lower plate inlet path is filled by using graded tailing cemented filling at first, then the graded tailing cemented filling is used for filling for 0.4m, the cement body sand-lime ratio is 1: 4, the roof connection is ensured, and the safe operation of equipment on the cemented body after the layer is changed is ensured. And after the cemented filling body is maintained for 72 hours, stoping is allowed to be carried out on adjacent routes, and after the two-layer lower-tray route is finished, the goaf is filled by adopting graded tailings to abut against the top.
6) And (7) rotating the layer. Before filling a layered footwall approach, the extrapulse draw shaft is jacked and erected along the way to the level of a layered ore body bottom plate, and the layered footwall approach, the cutting lane, the draw shaft connecting lane and the layered connecting lane are jacked and filled together to finish the layer transfer work. And then constructing a two-layered combined tunnel and a cutting tunnel by using the slope way outside the vein to control the ore body, constructing a draw shaft combined tunnel to pass through the outside-vein smooth shaft, and entering two-layered mining.
The Alhada lead-zinc ore is mined from an open stope method to a filling method, a large number of high-value ore pillars are left after many years of mining, under the condition of a non-reinforced cement tailing cemented body, by controlling the thickness of a safety protective layer mined by a top pillar, selecting an upward small-drift filling mining method mining process, adopting a non-electric millisecond delay detonation technology and a smooth blasting technology, and applying technical means and measures such as an anchor rod combined with a steel belt support, a metal bracket support and the like, the safety problem of resource recovery is effectively solved, the structural adjustment and the sustainable development of a mine production system are promoted, economic and social benefits are win-win, technical support is provided for the recovery of mine tailings, and technical reference is also provided for similar mines in the same industry.
The above embodiments are only specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention, and all should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. The utility model provides a mine remains pillar recovery system which characterized in that: the device comprises a drilling blasting device, a ventilating device, a supporting device, a ore removal device and a filling device, wherein the supporting device comprises a support leg and a top beam which are connected with each other, reinforcing tie bars are arranged between the support leg and the top beam, a U-shaped groove is formed in the top end of the support leg, and the top beam is arranged in the U-shaped groove and welded; and a fixed rib plate is further arranged between the support leg and the top beam, and the supporting device can be installed in a stoping access.
2. The mine carryover pillar extraction system of claim 1, wherein: the supporting device is fixed on the fixed round steel of the side wall or the top wall of the working face of the stoping access way through a connecting piece.
3. The mine carryover pillar extraction system of claim 2, wherein: the support legs and the top beam are made of I-shaped steel.
4. The mine carryover pillar extraction system of claim 3, wherein: the support leg is further provided with a fixing base plate, and two sides of the support leg are provided with wood plates.
5. The mine carryover pillar extraction system of claim 4, wherein: the top beam is provided with a wood board and is plugged and connected with the top through a wood pile formed by arranging a plurality of round wood in a shape like a Chinese character 'jing'.
6. The mine carryover pillar extraction system of claim 1, wherein: the ore removal device is a scraper, and the stoped ore is conveyed to the ore pass outside the stope through the scraper.
7. The mine carryover pillar extraction system of claim 1, wherein: and the rock drilling blasting device is used for drilling by an air leg type rock drill.
8. The mine carryover pillar extraction system of claim 1, wherein: the ventilation device comprises a press-in type fan and a draw-out type fan.
9. A mine carryover pillar extraction system according to any one of claims 1 to 8 wherein: also comprises a filling device.
10. The mine carryover pillar extraction system of claim 9, wherein: the filling device comprises a bulk ore cleaning device, a filling pipeline frame, a water draining cage and a steel mesh plate wall capable of closing an inlet road junction.
CN202120066441.7U 2021-01-11 2021-01-11 Mine left-over pillar extraction system Active CN214145491U (en)

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Application Number Priority Date Filing Date Title
CN202120066441.7U CN214145491U (en) 2021-01-11 2021-01-11 Mine left-over pillar extraction system

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Application Number Priority Date Filing Date Title
CN202120066441.7U CN214145491U (en) 2021-01-11 2021-01-11 Mine left-over pillar extraction system

Publications (1)

Publication Number Publication Date
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