A safe and efficient mining method with low loss for gently inclined polymetallic ore bodies

Abstract

The present invention belongs to the field of mining technology, and proposes a method for low-pollution, safe and efficient mining of gently inclined polymetallic ore bodies, including mining method design and selection, research on optimization of stope structure parameters, obtaining rock specimens for rock mechanics tests, rock mass quality classification using rock mass RMR scoring values ​​and Q system evaluation methods, mining industrial tests, and finally promoting and applying the production model of the test stope to the entire mine. The method for low-pollution, safe and efficient mining of gently inclined polymetallic ore bodies proposed by the present invention can derive a suitable mining method by a scientific analysis method, and ensure mining safety and efficiency, and adopts a scraper conveyor suitable for low-pollution, safe and efficient mining of gently inclined polymetallic ore bodies to transport ore materials, which has a reasonable design, high transmission efficiency, and is conducive to extending the actual service life of the equipment and improving the working efficiency of the equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of mining, and in particular relates to a method for mining a gently inclined polymetallic ore body with low dilution and loss, safety and high efficiency. Background Art

[0002] Gently inclined ore bodies are generally mined by backfill or subsequent backfilling, and a few mines use open-pit mining methods such as room-and-pillar mining. The choice of mining method is based on the occurrence conditions of the ore body, the physical and mechanical properties of the ore and surrounding rock, and is also related to the recovery process and equipment.

[0003] With the scientification of mining, many mines have gradually adopted a more systematic mining method, such as a safety pillar mining method disclosed in the existing patent CN111695790A, which mainly includes the following steps: S1: Analyze the geology of the mining area; S2: Collect the ore and rock in the mining area; S3: Analyze the physical and mechanical parameters of the ore and rock in the mining area; S4: Evaluate the quality of the rock mass in the mining area, and correct the mechanical parameters of the rock mass in combination with the rock mass quality evaluation; S5: Three-dimensional modeling, establish a three-dimensional numerical model of mining; S6: Numerical calculation and analysis, using the three-dimensional numerical model in combination with the calculation simulation software and the basic model, and setting boundary conditions and initial conditions to simulate the stress and deformation of the shaft structure under the condition of safety pillars of different sizes; S7: Determine the mining range of the safety pillars of the shaft, and obtain the minimum net radius of the safety pillars that can provide protection by analyzing and calculating the net radius of the safety pillars with different net radii in S6. This method is suitable for room-and-pillar mining, but not for backfill mining. In addition, since some gently inclined, thick, high-sulfur polymetallic ore bodies have a gentle inclination angle of 10 to 30°, it is not easy for the ore in the mining area to flow by its own weight. Therefore, reasonable handling equipment is required from the bottom level to the ore discharge level and then to the mine mouth for ore discharge.

[0004] Generally, the mining equipment adopts scraper conveyor, slag rake, bucket car and electric rake, etc. Among them, the scraper conveyor is disclosed in the existing patent CN218370155U, which is a scraper conveyor with dust removal function for underground production in coal mines, CN209192866U, which is a scraper conveyor for coal mines, and CN203975771U, which is a scraper conveyor sprocket for coal mines. In this case, the problem of the scraper conveyor is that the scraper needs to be installed on the chain, and the conveying action is completed through the transmission of the chain, sprocket and reduction mechanism. In particular, many scraper conveyors use double-row chains or even more rows of chains, which is easy to cause The jamming situation affects the real-time conveying efficiency of the conveyor, and the workload of troubleshooting is also relatively large; secondly, the feed end hopper at the mine outlet level mostly adopts a single-mouth, and the ore falling from the single mouth first hits the upper horizontal scraper and chain, and then falls on the lower horizontal scraper and chain. This can easily cause instability in the chain transmission system and increase the friction between the scraper and the chain, affecting the actual service life of the scraper and chain; secondly, the general scraper conveyor at the mine outlet level first transports horizontally and then transports above the mine outlet. In this case, the scraper has a large resistance to scraping materials, affecting the actual working efficiency of the machine. Summary of the invention

[0005] In view of the technical problems existing in the above-mentioned scraper conveyors, the present invention proposes a method for safe and efficient low-loss mining of gently inclined polymetallic ore bodies, which can derive a suitable mining method through a scientific analysis method and ensure mining safety and efficiency. The scraper conveyor suitable for safe and efficient low-loss mining of gently inclined polymetallic ore bodies is used to transport the ore. The scraper conveyor has a reasonable design and high transmission efficiency, is conducive to extending the actual service life of the equipment, and is conducive to improving the working efficiency of the equipment.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is that the method for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies provided by the present invention comprises the following steps:

[0007] S1. Design and selection of mining methods: Preliminary selection of mining schemes, comparison and evaluation of the advantages and disadvantages of different mining methods, selection of evaluation factors, including production efficiency, safety factors, economic factors, resource utilization, and rationality, application of fuzzy mathematical methods for comprehensive comparison of schemes, and selection of the segmented filling method as the mining method for polymetallic ore bodies with a gentle inclination of 15 to 20 degrees;

[0008] S2. Optimization of stope structure parameters: FLAC3D analysis software is used to conduct numerical simulation optimization of stope structure parameters of mining methods; the stress magnitude, displacement change law and plastic zone development of the stope surrounding rock during the mining process are analyzed to obtain the optimized stope structure parameters, which include layer height, stope span, stope width and stope length;

[0009] S3. Obtain rock specimens for rock mechanics tests and classify rock quality using rock mass RMR scores and Q system evaluation methods;

[0010] S4. Industrial mining test: carry out industrial test in the ore body, divide the stope model, and use a scraper conveyor suitable for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies to transport the ore materials. The scraper conveyor adopts a steel rope continuous circulation drive, and the scraper conveyor transports the ore materials from the bottom level to the mine level, and then to the mine mouth;

[0011] S5. Finally, the production model of the test mine will be promoted and applied to the entire mine.

[0012] Preferably, in step S4, the mining field model is divided into 10 meters for one-step mining and 8 meters for two-step mining. The mining field is divided into several mining fields for each layer, and the ore body contour is expanded according to the length distance to ensure that there is enough space for the layered connecting tunnels. Finally, the center line of the bottom plate of the segmented vein outer tunnel, the flat slope section, the uphill section, the downhill section, the segmented ore body and the segmented vein outer tunnel are generated according to the expanded ore body contour.

[0013] Preferably, in step S4, a scraper conveyor suitable for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies is arranged inside a horizontal ore discharge box and an upward ore discharge box, a ore discharge hopper is arranged above the horizontal ore discharge box, the scraper conveyor includes an upper conveying section and a lower conveying section, a plurality of turning arc conveying sections are arranged between the upper conveying section and the lower conveying section, the ore discharge hopper includes a main bucket, two symmetrically distributed sub-buckets are arranged at the bottom of the main bucket, and the sub-buckets include a first vertical conveying section connected in sequence from top to bottom. The first inclined sections of the two sub-buckets are symmetrically distributed in an inverted V shape, and the second inclined sections of the two sub-buckets are symmetrically distributed in a positive V shape. The space formed by the relative directions of the two sub-buckets is used to pass the upper conveying section. The ends of the two sub-buckets are both facing the lower conveying section. The bottom of the lower conveying section is a V-shaped gentle slope structure. The end of the gentle slope structure is provided with a lifting section extending upward toward the mine mouth. The V-shaped bottom of the gentle slope structure is located between the side of the sub-bucket and the lifting section.

[0014] Preferably, the scraper conveyor comprises a plurality of scraper pairs, a link unit is arranged in the middle of adjacent scraper pairs, transmission holes are arranged at both ends of adjacent scraper pairs, a rope-connected transmission unit is arranged at the transmission hole, a clamping hole for clamping a steel rope is arranged at one end of the rope-connected transmission unit, a transmission rod is arranged at the other end of the rope-connected transmission unit, the transmission rod is perpendicular to the conveying direction of the scraper conveyor, the turning arc conveying section is provided with a paddle wheel transmission mechanism which cooperates with the transmission rod, a reduction motor is arranged at the power input end of the paddle wheel transmission mechanism, a plurality of rolling support mechanisms are arranged between the upper conveying section and the lower conveying section, and the middle of the rolling support mechanism is rollingly matched with the link unit.

[0015] Preferably, the scraper pair includes two scrapers, the scraper includes a main board, the end of the main board facing the link unit is provided with an end plate connected to the main board in a cross shape, the link unit includes a circular plate, the diameter of the circular plate is larger than the vertical width of the main board and larger than 1 / 3 of the length of the end plate, the circular plate is provided with pairs of holes, the pairs of holes are connected to the end plate by countersunk bolts, the rolling support mechanism includes a pair of support bearing seats, a support shaft is provided between the support bearing seats, a support plate is provided in the middle of the support shaft, and the disk edge of the support plate is provided with a rolling support groove that cooperates with the circular plate.

[0016] The end portion of the plug plate is provided with a column head, and one end of the column head is provided with a plug hole connected with the gap between the two plug plates. The C-shaped tube, the plug plate portion, the column head and the transmission rod are connected as a whole, and the end portion of the transmission rod is provided with a stepped limiting end plate, and the two ends of the C-shaped tube are provided with a hollow connector threadedly connected to the tube wall. The clamping hole is arranged at the center of the hollow connector, and the end of the hollow connector is provided with a card groove radially connected to its side surface, and the card groove, the gap of the plug plate and the plug hole constitute a positioning groove, and a pair of positioning plates plugged in opposite directions are arranged in the positioning groove, and a pair of positioning tenons are arranged on the plate surface of the positioning plate, and the positioning tenons cooperate with the positioning holes arranged on the plug plate and the column head.

[0017] Preferably, the dial transmission mechanism includes a dial wheel, which is provided with a plurality of dial notches evenly distributed in a circular array along its edge, the dial notches are used to slide with the transmission rod, one side of the dial notch is an inclined surface, the other side of the dial notch is a stepped surface, and the distance from the stepped surface to the inclined surface decreases from the outside to the inside.

[0018] Preferably, the thumbwheel comprises an axially distributed first thumbwheel and a second thumbwheel, a convex lip is provided on the opposite surfaces of the first thumbwheel and the second thumbwheel, the convex lip forms a wheel groove with the first thumbwheel and the second thumbwheel, a buffer is provided in the wheel groove, the buffer comprises a slip ring cooperating with the convex lip, a gear ring cooperating with the slip ring and the groove surface of the wheel groove is provided in the wheel groove, a plurality of clamping teeth corresponding to the thumbwheel openings are provided on the ring surface of the gear ring, annular grooves are provided on both sides of the gear ring, a plate-shaped buffer spring is provided in the annular groove, the buffer spring is a C-shaped structure and two connecting feet are provided at both ends thereof, and the two connecting feet are respectively connected to the gear ring and the thumbwheel.

[0019] Preferably, a plurality of weight-reducing holes are provided on the first and second paddle wheels, bolt holes are provided in the weight-reducing holes, clamping bolts for connecting the first and second paddle wheels are provided in the bolt holes, the cross-section of the wheel groove is an isosceles trapezoid, the spring surface of the buffer spring is parallel to the waist of the isosceles trapezoid after being clamped by the paddle wheel and the gear ring, and the buffer spring is spiral in a natural state and its spiral length is less than one circle.

[0020] Preferably, the horizontal ore-discharging box and the upward ore-discharging box are provided with guide rails for slidingly cooperating with the transmission rods.

[0021] Compared with the prior art, the advantages and positive effects of the present invention are:

[0022] 1. The method for low-depletion, safe and efficient mining of gently inclined polymetallic ore bodies provided by the present invention adopts a scientific method to conduct a comprehensive analysis of the ore body to conclude that the mining method suitable for gently inclined polymetallic ore bodies with a slope of 15 to 20 degrees is the segmented filling method, and a three-dimensional analysis method is used to obtain the optimized stope structure parameters, and the rationality of mining is further ensured through rock mechanics tests and mining industrial tests. After verifying the rationality and efficiency, it is applied to the entire mine, thereby ensuring mining safety and efficiency, and also embodying the high selectivity, high ore recovery rate and low depletion rate of the layered segmented filling method.

[0023] 2. The method for safe and efficient low-loss mining of gently inclined polymetallic ore bodies provided by the present invention adopts a scraper conveyor with continuous circulation transmission by steel ropes. It is not only suitable for safe and efficient low-loss mining of gently inclined polymetallic ore bodies, but also has the advantage of high transmission efficiency, which is beneficial to extending the actual service life of the equipment and improving the working efficiency of the equipment. It is also reasonably designed and suitable for large-scale promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 It is the front view of the horizontal ore discharge box, the upward ore discharge box, the ore discharge hopper and the scraper conveyor;

[0026] Figure 2 Axonometric drawings of the horizontal ore discharge box (open), the upward ore discharge box, the ore discharge hopper and the scraper conveyor;

[0027] Figure 3 It is a cross-sectional view of the horizontal ore discharge box, the upward ore discharge box, the ore discharge hopper and the scraper conveyor in the GG direction;

[0028] Figure 4 A schematic diagram of the distribution of the scraper conveyor provided in the embodiment inside the horizontal box of the ore discharge;

[0029] Figure 5 Axonometric drawing of the scraper pair connected by steel rope;

[0030] Figure 6 An exploded view of a scraper pair, a link unit and a rope-connected transmission unit provided in an embodiment;

[0031] Figure 7 An axonometric view of a rolling support mechanism provided for an embodiment;

[0032] Figure 8 An exploded view of a rope-connected transmission unit provided in an embodiment;

[0033] Fig. 9 An exploded view of a thumbwheel transmission mechanism provided in an embodiment;

[0034] Fig.10 A front view of a thumbwheel transmission mechanism provided in an embodiment;

[0035] Fig.11 A schematic diagram of the operation of the buffer on the thumbwheel provided in the embodiment;

[0036] In the above figures, 1, horizontal box for ore discharge; 2, upward ore discharge box; 3, ore discharge funnel; 31, main bucket; 32, sub-bucket; 321, first vertical section; 322, first inclined section; 323, second vertical section; 324, second inclined section; 4, scraper conveyor; 41, upper conveying section; 42, lower conveying section; 43, turning arc conveying section; 44, scraper pair; 441, main board; 442, end plate; 45, link unit; 451, round plate; 452, matching hole; 453, countersunk bolt; 46, transmission hole; 461, C-shaped part; 462, straight part; 47, rope-connected transmission unit; 471, clamping hole; 472, transmission rod; 473, C-shaped tube; 474, plug plate; 475, column head; 476, plug hole; 477, stepped limit end plate ;478, hollow connector;479, slot;4710, positioning plate;4711, positioning tenon;4712, positioning hole;48, steel rope;49, dial transmission mechanism;491, dial;4911, first dial;4912, second dial;4913, convex lip;492, dial mouth;4921, inclined surface;4922, stepped surface;493, buffer;4931, slip ring;4932, gear ring;4933, clamping tooth;4934, ring groove;4935, buffer spring;4936, connecting foot;494, weight reduction hole;495, bolt hole;410, reduction motor;411, rolling support mechanism;4111, support bearing seat;4112, support shaft;4113, support plate;4114, rolling support groove;5, guide track. DETAILED DESCRIPTION

[0037] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict. For the convenience of description, if the words "upper", "lower", "left" and "right" appear below, they only indicate that the upper, lower, left and right directions are consistent with the accompanying drawings themselves, and do not limit the structure.

[0038] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0039] Examples, such as Figures 1 to 11As shown, the invention provides a low-pollution, safe and efficient mining method for a gently inclined polymetallic ore body, S1, mining method design and selection: preliminarily select several mining schemes, compare the mining methods of different schemes and comment on their advantages and disadvantages, select evaluation factors, the evaluation factors include production efficiency, safety factors, economic factors, resource utilization, and rationality, apply fuzzy mathematics methods to conduct comprehensive comparison of the schemes, and select the mining method suitable for the gently inclined polymetallic ore body as the segmented filling method;

[0040] S2. Optimization of stope structure parameters: FLAC3D analysis software is used to conduct numerical simulation optimization of stope structure parameters of mining methods; the stress magnitude, displacement change law and plastic zone development of the stope surrounding rock during the mining process are analyzed to obtain the optimized stope structure parameters, which include layer height, stope span, stope width and stope length;

[0041] S3. Obtain rock specimens for rock mechanics tests and classify rock quality using rock mass RMR scores and Q system evaluation methods;

[0042] S4. Industrial mining test: carry out industrial test in the ore body, divide the stope model, and use a scraper conveyor suitable for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies to transport the ore materials. The scraper conveyor adopts a steel rope continuous circulation drive, and the scraper conveyor transports the ore materials from the bottom level to the mine level, and then to the mine mouth;

[0043] S5. Finally, the production model of the test mine will be promoted and applied to the entire mine.

[0044] The evaluation of the mining scheme preliminarily selected in step S1 can be evaluated based on the mining scheme of the existing specific ore body, such as Mine A, Mine B, Mine C and Mine C respectively adopted the caving and subsequent filling method, the segmented empty field and subsequent filling mining method, the upward approach paste filling mining method and the upward horizontal layered dry filling mining method.

[0045] More specifically, Mine A adopts the development method of inclined shaft + inclined ramp. The mine is mainly lead, zinc and copper ore bodies, which are stable in occurrence, generally single-layer, and branched into two layers in some sections. The ore bodies are thick and large, the surrounding rock is moderately stable, and the ore bodies are stable. The mine is mainly a gently inclined thick and large ore body. In terms of resource utilization and rationality, for the main ZnV3 ore body of the mine, the thickness is generally greater than 20m. The large-diameter deep hole subsequent filling mining method uses spherical explosive bags with an aspect ratio of no more than 6. The explosive effect is increased, and the broken rocks collide and squeeze with each other during the movement, which is conducive to better crushing. The amount of ore collapsed by the inverted funnel blasting is also large. Therefore, the blasting effect of spherical explosive bags is generally considered to be better than that of other shapes of explosive bags. This type of mining method is generally suitable for thick ore bodies with a thickness of not less than 15m.

[0046] B Mine (copper mine) is a shallow medium (low) temperature volcanic-subvolcanic hydrothermal deposit. In terms of geology, the ore body is distributed between the 5A~12A exploration lines, with a strike length of about 400m and a dip extension of 650m; the ore body is present at an elevation of +280m to -150m, and a burial depth of 30m to 450m. In terms of resource utilization, the thickness of the ore body ranges from a few meters to tens of meters, with the thickest being 50m, thin ore bodies accounting for 45%, medium-thick ore bodies accounting for 20%, and thick ore bodies accounting for 25%. In terms of production efficiency and rationality, the thickness of the ore body varies greatly, so the ore blocks are arranged vertically and mined in two steps; in the construction plan, the width of the mine room and the pillar is 15m, the length is the horizontal thickness of the ore body, the middle section height is 30~36m, and the section height is 10~12m.

[0047] The C mine is a nonferrous metal mine. The ore body is mainly located in mineralized slate. The bedding is particularly developed. Affected by the later structural joints, the ore rock is broken. There are sand layers, conglomerate layers and oxidized ore zones in both the upper and lower plates, and the stability of the ore rock is poor. The western ore body has a gentle inclination of about 30°, an average thickness of 7.36m, and a strike length of 1400-2100m. It is a typical gently inclined, medium-thick, complex and difficult-to-mine ore body. At the same time, in terms of geology, safety factors and resource utilization, the western ore body is a sedimentary deposit with abundant groundwater. The ore-bearing layer and the direct top and bottom plates of the ore body are all water-containing. There is a strongly weathered flint dolomite rich water layer in its upper plate, and the shallow rock layer has good permeability. Affected by hydrogeological factors such as precipitation and surface water, the current drainage volume of the western ore body is 25,000t / d, and it is difficult to drain the groundwater, which makes it difficult to support the mining and cutting engineering, difficult to maintain the engineering, and increases safety hazards. The construction plan, according to the ore body occurrence conditions, is designed to use the upward horizontal layered filling mining method, with a segment height of 16m, 5 layers of mining, a layer height of 3.2m, a stope (access) width of 3.7m, and an access length of 60m. After the first layer is mined, the waste rock is filled with about 2.5m, and then the upper layer is mined by picking the top, and so on, until the fifth layer is mined. In the actual production process, based on the on-site investigation, the preliminary design of the mine was adjusted and optimized twice by numerical simulation, and the current upward access paste filling mining method was finally determined. According to the analysis results, the stope length is finally determined to be 60m, the segment height is 16m, and the mining is divided into 4 layers, the layer height is 4m, the stope thickness is the ore body thickness, the number of accesses is divided according to the ore body thickness, and the access section size is (4~6)m×4m. When the same layer is mined, it is mined from the upper wall to the lower wall in sequence. After the mining of the lower layer is completed, the mining will start from the upper layer until all the layers are mined.

[0048] The D mine mainly includes a variety of metals such as Cu, Zn, Pb, W, Sn, etc., while granite porphyry and quartz porphyry have a close spatial relationship with the ore deposit. The stope is arranged according to the horizontal thickness of the ore body. When the horizontal thickness of the ore body is less than 15m, the stope is arranged along the direction of the ore body in the upward horizontal layered dry filling mining method, and the length of the mine room should be controlled at about 30-50m. The stope hopper is connected by a metal template with a diameter of 1.5m. The diameter of the waste rock filling shaft is 1.5m, the pedestrian skylight is 1.5m×2.6m, the skylight connecting road is 1.5m×1.8m, the transport level shaft is 2.4m×2.7m, and the filling and transportation is pulled by a 3t overhead line electric locomotive with a length of 0.7m 3 The dump truck is used to transport the waste rock in each section, and the 7t overhead line electric locomotive is used to pull the 1.2m 3 Side dump mine car.

[0049] In step S1, by comparing the mining cases of A, B, C, and D mines, the mining method suitable for the gently inclined polymetallic ore body of 15 to 20 degrees can be selected as the segmented filling method. Step S2 can scientifically analyze the shape, trend, and distribution of the specific ore deposit, and as a relatively mature 3D analysis and demonstration technology, FLAC3D analysis software can help the construction team obtain more reasonable stope structure parameters before construction, reduce the difficulty of industrial experiments, and promote the progress of comprehensive implementation of mining. In the process of optimizing the stope structure parameters, according to the actual conditions of the specific mine, specific values ​​of the layer height, stope span, stope width, and stope length that meet the multi-vein mining can be proposed. For example, for the gently inclined multi-vein ore body of 15 to 20 degrees, its layer height is increased to 4m, the stope span is expanded to 8m, the stope width is adjusted to 8-12m, and the stope length is adjusted to 55m. In addition, taking into account the problems of small single-shot blasting volume and relatively high mining cost in the downward approach cemented filling mining method, field tests were carried out on three different cross-sectional sizes of mining approaches, including 5m×4.5m, 5.5m×4.5m and 6.0m×4.5m. The maximum vertical compressive stress of the mining approach roof, the maximum subsidence of the roof and the maximum convergence deformation of the two sides were obtained, and the optimal cross-sectional size of 5.0m×4.5m was determined.

[0050] After multiple field surveys, the sampling locations were selected at the middle sections of -326M, -526M and -540M. Rock mechanics work was carried out by using two methods: large-scale on-site excavation and core drilling. The rock samples selected on site were processed into standard specimens. The processed rock specimens were subjected to basic physical and mechanical parameters, uniaxial compression deformation and splitting tests to obtain the relevant rock mechanics properties of the rock specimens.

[0051] About rock mass classification indicators:

[0052] The rock mass RMR score is composed of six parameters, namely rock strength R1, rock quality index (RQD) R2, joint spacing R3, joint state R4, groundwater state R5 and joint strike R6. The RMR value is obtained based on the sum of the six parameters, and the rock mass quality grade is divided into five categories.

[0053] The Q system evaluation rule mainly considers the influence of rock mass integrity, joint characteristics, groundwater and ground stress, and uses six parameters to determine the rock mass quality index Q value that reflects the stability of the tunnel surrounding rock.

[0054] Through experiments and statistical data, the rock quality indicators RQD, the number of joint groups Jn, the roughness coefficient of the most fragile joint Jr, the erosion degree or filling condition of the most fragile joint surface Ja, the fissure water reduction coefficient Jw and the stress reduction factor SRF of each section in the mining tunnel were obtained. Combined with the on-site geological survey data, the structural surface conditions and groundwater conditions were analyzed, and the scoring values ​​of each indicator in each section were given, and the corresponding rock quality classification was obtained.

[0055] By establishing a numerical calculation model for mining of gently inclined, thick, high-sulfur polymetallic ore bodies, the temporal and spatial evolution characteristics of stress-strain in mining of gently inclined, thick, high-sulfur polymetallic ore bodies were studied, and the stress size, displacement change law and plastic zone development of the mining area surrounding rock during the mining process were analyzed to obtain the optimized mining area structural parameters. The corresponding data were adjusted, and the field test of the mining area approach with the same cross-sectional size was carried out to select the optimal cross-sectional size, such as 10.0m×8.0m.

[0056] In step S4, the stope model is divided into 10 meters for one-step mining and 8 meters for two-step mining. Each layer is divided into several stopes, and the ore body contour is expanded according to the length distance to ensure that there is enough space for the layered connecting lanes. Finally, the middle line of the floor of the segmented vein outer lane, the flat slope section, the uphill section, the downhill section, the segmented ore body and the segmented vein outer lane are generated according to the expanded ore body contour. This is conducive to improving the rationality of the mining process of the gently inclined polymetallic ore body, the mining efficiency and the recovery rate of the ore.

[0057] The method for low-depletion, safe and efficient mining of gently inclined polymetallic ore bodies provided by the present invention adopts a scientific method to conduct a comprehensive analysis of the ore bodies to conclude that the mining method suitable for gently inclined polymetallic ore bodies with a slope of 15 to 20 degrees is a segmented filling method, and a three-dimensional analysis method is used to obtain optimized stope structure parameters, and rock mechanics tests and mining industrial tests are used to further ensure the rationality of mining. After verifying the rationality and efficiency, the method is applied to the entire mine, thereby ensuring mining safety and efficiency, and also embodying the high selectivity, high ore recovery rate and low depletion rate of the layered segmented filling method.

[0058] In order to improve the mining efficiency, in step S4, the present invention proposes a scraper conveyor 4 suitable for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies, wherein the scraper conveyor 4 is arranged inside a horizontal ore-discharging box 1 and an upward ore-discharging box 2, and an ore-discharging funnel 3 is arranged above the horizontal ore-discharging box 1, the scraper conveyor 4 includes an upper conveying section 41 and a lower conveying section 42, and a plurality of turning arc conveying sections 43 are arranged between the upper conveying section 41 and the lower conveying section 42, and the ore-discharging funnel 3 includes a main bucket 31, and two symmetrically distributed sub-buckets 32 are arranged at the bottom of the main bucket 31, and the sub-buckets 32 include a first A vertical section 321, a first inclined section 322, a second vertical section 323 and a second inclined section 324, the first inclined sections 322 of the two sub-buckets 32 are symmetrically distributed in an inverted V shape, and the second inclined sections 324 of the two sub-buckets 32 are symmetrically spaced and distributed in a positive V shape. The space formed by the relative directions of the two sub-buckets 32 is used to pass the upper conveying section 41. The ends of the two sub-buckets 32 are both facing the lower conveying section 42. The bottom of the lower conveying section 42 is a V-shaped gentle slope structure. A lifting section extending upward toward the mine mouth is provided at the end of the gentle slope structure. The V-shaped bottom of the gentle slope structure is located between the side of the sub-bucket 32 ​​and the lifting section. In this way, when the ore from top to bottom enters the mining level, it directly enters the area where the gentle slope structure is located from the two sub-buckets 32, and will not collide and impact with the upper conveying section 41 of the scraper conveyor 4, thereby reducing the impact of the ore on the stability of the scraper conveyor 4 in the conveying direction. On this basis, the number of frictions between the ore and the scraper and chain is reduced, which is conducive to extending the actual service life of the scraper and chain. At the same time, if a gentle slope structure is designed, part of the power and gravity of the ore can be converted into the power of the lower conveying section 42 after acting on the scraper on the lower conveying section 42, which can reduce the resistance of the scraper conveyor 4 in the conveying direction to a certain extent, and ensure that the reverse resistance of the lifting section will not be excessively increased, which can reduce the output power consumption and help improve the working efficiency of this equipment.

[0059] In order to improve the transmission efficiency of the scraper conveyor 4, the scraper conveyor 4 provided by the present invention includes a plurality of scraper pairs 44, a link unit 45 is arranged in the middle of adjacent scraper pairs 44, transmission holes 46 are arranged at both ends of adjacent scraper pairs 44, a rope-connected transmission unit 47 is arranged at the transmission hole 46, a clamping hole 471 for clamping a steel rope 48 is arranged at one end of the rope-connected transmission unit 47, a transmission rod 472 is arranged at the other end of the rope-connected transmission unit 47, the transmission rod 472 is perpendicular to the conveying direction of the scraper conveyor 4, the turning arc conveying section 43 is provided with a dial wheel 491 transmission mechanism 49 that cooperates with the transmission rod 472 for transmission, a reduction motor 410 is arranged at the power input end of the dial wheel 491 transmission mechanism 49, a plurality of rolling support mechanisms 411 are arranged between the upper conveying section 41 and the lower conveying section 42, and the middle of the rolling support mechanism 411 is rollingly matched with the link unit 45. Among them, the number of rolling support mechanisms 411 can be reasonably selected according to the actual length of the upper conveying section 41 and the lower conveying section 42 in the horizontal box 1 of the ore discharge, mainly considering the tensioning effect of the scraper conveyor 4, but the rolling support mechanism 411 is not set at the discharge port of the bucket 32 ​​to avoid affecting the scraper feeding. In particular, all the scraper pairs 44 are connected to form a circulatory component through the link unit 45 and the steel rope 48, and the link unit 45 is different from the general transmission chain. Not only will it not get stuck, but it can also cooperate with the rolling support mechanism 411 to ensure the transmission stability of the device; the cross-sectional area of ​​the steel rope 48 is relatively smooth, so it will not get stuck, and it can effectively ensure the stability and integrity of all scraper pairs 44 during the cyclic movement, which is conducive to improving the conveying efficiency. Furthermore, in addition to the power source being provided simultaneously by multiple reduction motors 410 distributed in reasonable positions, the present invention adopts a dial 491 transmission mechanism 49 to cooperate with a transmission rod 472 to transmit all scraper pairs 44, so that the scraper pairs 44 can be ensured to circulate on the conveying path, and the spacing between them is larger than the transmission chain, and the surface of the part that will come into contact with the mineral material is also relatively smooth, which can effectively avoid the situation of material jamming, and fully avoid the disadvantages of traditional double-row chains or even more rows of chains, effectively improve the real-time conveying efficiency of the scraper conveyor 4, and the scraper pairs 44 can still circulate during the inspection process. The inspection through the circulation method has much less impact on the inspection work than jamming. Therefore, the actual utilization rate of the scraper conveyor 4 is higher.

[0060] Furthermore, the scraper pair 44 provided by the present invention includes two scrapers, and the scraper includes a main board 441. The end of the main board 441 facing the link unit 45 is provided with an end plate 442 cross-connected with the main board 441. The link unit 45 includes a circular plate 451. The diameter of the circular plate 451 is greater than the vertical width of the main board 441 and greater than 1 / 3 of the length of the end plate 442. The circular plate 451 is provided with a pair of holes 452. The pair of holes 452 and the end plate 442 are connected by countersunk bolts 453. The rolling support mechanism 411 includes a pair of support shafts 4112 and seats 4111. The support shafts 4112 and seats 4111 are installed on the horizontal mining box 1. A support shaft 4112 is arranged between the support shafts 4112 and seats 4111. A support shaft 4112 is arranged in the middle of the support shaft 4112. A support disk 4113 is arranged on the disk edge of the support disk 4113, and a rolling support groove 4114 cooperating with the circular plate 451 is arranged. The scraper surface is used to scrape the ore, and the scraper uses the link unit 45 as a connection node. The circular plate 451 of the link unit 45 can compensate for the gap between the opposite surfaces of the scraper, reducing the probability of material jamming; and the arc surface of the circular plate 451 can facilitate the rolling of the ore in the scraping direction of the scraper, and even if the ore falls between adjacent circular plates 451 in an instant, it will not significantly affect the transmission process of the scraper. Furthermore, the circular plate 451 cooperates with the rolling support groove 4114 of the rolling support mechanism 411 to ensure the uniformity of the scraper in the scraping direction and reduce the probability of large-scale movement problems at both ends of the scraper.

[0061] In order to improve the connection performance between the steel rope 48 and the scraper and the transmission performance between the driving mechanism 49 of the paddle wheel 491 and the transmission rod 472, the transmission hole 46 provided by the present invention includes a C-shaped portion 461 and a straight-shaped portion 462 connected to the C-shaped portion 461, and the rope-connected transmission unit 47 includes a C-shaped tube 473 connected to the C-shaped portion 461, and both ends of the side opening of the C-shaped tube 473 are provided with a plug plate portion 474 matched with the straight-shaped portion 462, and the end of the plug plate portion 474 is provided with a column head 475, and one end of the column head 475 is provided with a plug hole 476 connected to the gap between the two plug plates, and the C-shaped tube 473, the plug plate portion 474, the column head 475 and the transmission rod 472 are connected to the C-shaped tube 473. 72 are integrally connected, the end of the transmission rod 472 is provided with a stepped limiting end plate 442, the two ends of the C-shaped tube 473 are provided with hollow connectors 478 threadedly connected to the tube wall, the clamping hole 471 is provided in the center of the hollow connector 478, the end of the hollow connector 478 is provided with a card slot 479 radially connected to the side surface thereof, the card slot 479, the gap of the plug plate and the plug hole 476 constitute a positioning groove, a pair of positioning plates 4710 plugged in opposite directions are provided in the positioning groove, a pair of positioning tenons 4711 are provided on the plate surface of the positioning plate 4710, and the positioning tenons 4711 cooperate with the positioning holes 4712 provided on the plug plate and the column head 475. Among them, the caliber of the C-shaped tube 473 is slightly larger than the caliber of the C-shaped portion 461 of the transmission hole 46, so that the C-shaped tube 473 can have a certain tension, and the plug plate portion 474 is used as the tensioning end to be plugged with the I-shaped portion 462, thereby increasing the friction between the C-shaped tube 473, the I-shaped portion 462 and the transmission hole 46; the column head 475 can further prevent the C-shaped tube 473 from moving parallel to the center direction of the transmission rod 472, which is beneficial to improving the stability of the transmission rod 472; the two hollow connectors 478 are worn on the steel rope 48 in a natural state, and have a certain degree of sliding freedom, and the hollow connector 478 is completely installed at the end of the C-shaped tube 473 If so, it can effectively achieve the function of clamping the steel rope 48, thereby ensuring the certainty of the position of each scraper pair 44 on the steel rope 48; after the hollow connecting head 478 is fully installed, the card groove 479 on its surface is consistent with the gap of the plug plate and the spatial direction of the plug hole 476. If the positioning plate 4710 is driven into the positioning groove with the help of a tool, in addition to using the end of the positioning plate 4710 to locate the orientation of the card groove 479, the positioning tenon 4711 on the positioning plate 4710 is also completely stuck in the positioning hole 4712, thereby completely determining the specific positions of the rope-connected transmission unit 47 and the scraper on the steel rope 48, thereby ensuring the continuous conveying performance of the scraper pair 44 of mineral materials.

[0062] Furthermore, the transmission rod 472 is stably fixed at the end of the scraper through the rope-connected transmission unit 47, and each transmission rod 472 can be driven one by one through the drive mechanism 49 of the dial wheel 491, thereby obtaining a stable conveying step length, thereby ensuring the transmission performance of the scraper conveyor 4.

[0063] In order to improve the transmission performance of the dial wheel 491 transmission mechanism 49, the dial wheel 491 transmission mechanism 49 provided by the present invention includes a dial wheel 491, and a plurality of dial openings 492 are evenly distributed in a circular array along the edge of the dial wheel 491. The dial openings 492 are used to slide with the transmission rod 472. One side of the dial opening 492 is an inclined surface 4921, and the other side of the dial opening 492 is a stepped surface 4922, and the distance from the stepped surface to the inclined surface 4921 decreases from the outside to the inside. Among them, the deepest part of the dial opening 492 is used to clamp the transmission rod 472 passing through the position of the dial opening 492, and the stepped design can make the transmission rod 472 have a certain buffer distance in the case of instantaneous fluctuations, so that the transmission rod 472 under the effective transmission working pressure will not be separated from the dial opening 492 originally matched with it, and the transmission rod 472 that is about to leave the dial opening 492 has a safe departure distance, so as to improve the conveying performance of the scraper conveyor 4.

[0064] Furthermore, the thumbwheel 491 provided by the present invention includes a first thumbwheel 4911 and a second thumbwheel 4912 distributed axially, a convex lip is provided on the opposite surface of the first thumbwheel 4911 and the second thumbwheel 4912, the convex lip and the first thumbwheel 4911 and the second thumbwheel 4912 form a wheel groove, a buffer 493 is provided in the wheel groove, the buffer 493 includes a slip ring 4931 matched with the convex lip, a gear ring 4932 matched with the slip ring 4931 and the groove surface of the wheel groove is provided in the wheel groove, and a plurality of gear rings 4932 are provided on the ring surface thereof to be aligned with the thumbhole 492. The corresponding clamping teeth 4933, the surface where the clamping teeth 4933 and the transmission rod 472 are clamped and matched is an inclined surface 4921, which applies a radial pressure to the transmission rod 472, but does not affect the transmission rod 472 from the outside to the inside to enter the clamping teeth 4933 and the dial port 492. Both sides of the gear ring 4932 are provided with annular grooves 4934, and a plate-shaped buffer spring 4935 is provided in the annular grooves 4934. The buffer spring 4935 is a C-shaped structure and has two connecting legs 4936 at both ends. The two connecting legs 4936 are respectively connected to the gear ring 4932 and the dial wheel 491. Among them, the slip ring 4931 can make the force on the gear ring 4932 come mostly from the buffer spring 4935, so that the disturbance of the buffer spring 4935 can be converted into the rotational displacement of the gear ring 4932. In this way, the clamping teeth 4933 of the buffer 493 are opposite to the shifting mouth 492. When the transmission rod 472 is shifted into the shifting mouth 492 by the dial wheel 491, the clamping teeth 4933 clamp the transmission rod 472 under the action of the buffer spring 4935, and apply a certain elastic force to the transmission rod 472. When the transmission rod 472 is disturbed, the buffer spring 4935 provides a restoring force, so that the transmission rod 472 is always in the effective shifting range, thereby ensuring the reliability of the transmission path.

[0065] In order to facilitate the assembly of the dial 491 transmission mechanism 49, the dial 491 adopts the form of a separate assembly of the first dial 4911 and the second dial 4912, and a plurality of weight-reducing holes 494 are provided on the first dial 4911 and the second dial 4912 to reduce the working torque of the reduction motor 410, and bolt holes 495 are provided in the weight-reducing holes 494, and clamping bolts for connecting the first dial 4911 and the second dial 4912 are provided in the bolt holes 495.

[0066] In order to improve the timeliness of the restoring action generated by the restoring force of the buffer spring 4935, the cross section of the wheel groove is designed to be an isosceles trapezoid, and the spring surface of the buffer spring 4935 is parallel to the waist of the isosceles trapezoid after being clamped by the paddle wheel 491 and the gear ring 4932. The buffer spring 4935 is spiral in a natural state and its spiral length is less than one circle. In this way, after the buffer spring 4935 is clamped between the first paddle wheel 4911, the gear ring 4932 and the second paddle wheel 4912, its accumulated restoring force is greater than the restoring force of the spring of the plane C-shaped structure, so the clamping effect on the transmission rod 472 is better, and the recovery response can be generated more quickly after the transmission rod 472 is disturbed, thereby ensuring the orderly transmission performance of the transmission mechanism 49 of the paddle wheel 491 to the transmission rod 472.

[0067] In order to ensure that the scraper conveyor 4 has a stable ore-discharging direction and ore-discharging path, the horizontal ore-discharging box 1 and the upward ore-discharging box 2 provided by the present invention are provided with guide rails 5 for slidingly cooperating with the transmission rod 472. In this way, the scraper can be supported by the transmission rod 472 during the transmission and transportation process, and can effectively circulate along the predetermined guide rails 5, thereby completing continuous ore-discharging operations.

[0068] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies, characterized in that: The following steps are involved: S1. Design and selection of mining methods: Preliminary selection of mining schemes, comparison and evaluation of the advantages and disadvantages of different mining methods, selection of evaluation factors, including production efficiency, safety factors, economic factors, resource utilization, and rationality, application of fuzzy mathematical methods for comprehensive comparison of schemes, and selection of the segmented filling method as the mining method for gently inclined polymetallic ore bodies with a slope of 15 to 20 degrees; S2. Optimization of stope structure parameters: FLAC3D analysis software is used to conduct numerical simulation optimization of stope structure parameters of mining methods; the stress magnitude, displacement change law and plastic zone development of the stope surrounding rock during the mining process are analyzed to obtain the optimized stope structure parameters, which include layer height, stope span, stope width and stope length; S3. Obtain rock specimens for rock mechanics tests, and use rock mass RMR scores and Q system evaluation method to classify rock mass quality; S4. Industrial mining test: carry out industrial test in the ore body, divide the stope model, and use a scraper conveyor suitable for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies to transport the ore materials. The scraper conveyor adopts a steel rope continuous circulation drive, and the scraper conveyor transports the ore materials from the bottom level to the mine level, and then to the mine mouth; S5. Finally, the production model of the test stope will be extended and applied to the entire mine; In step S4, a scraper conveyor suitable for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies is arranged inside a horizontal ore discharge box and an upward ore discharge box, an ore discharge hopper is arranged above the horizontal ore discharge box, the scraper conveyor includes an upper conveying section and a lower conveying section, a plurality of turning arc conveying sections are arranged between the upper conveying section and the lower conveying section, the ore discharge hopper includes a main bucket, two symmetrically distributed sub-buckets are arranged at the bottom of the main bucket, the sub-buckets include a first vertical section, a first inclined section, a second vertical section and a second inclined section connected in sequence from top to bottom, the first inclined sections of the two sub-buckets are symmetrically distributed in an inverted V shape, the second inclined sections of the two sub-buckets are symmetrically spaced and distributed in a positive V shape, the space formed by the relative directions of the two sub-buckets is used to pass through the upper conveying section, the ends of the two sub-buckets are both facing the lower conveying section, the bottom of the lower conveying section is a V-shaped gentle slope structure, the end of the gentle slope structure is provided with a material lifting section extending upward toward the mine mouth, and the V-shaped bottom of the gentle slope structure is located between the side of the sub-bucket and the material lifting section; The scraper conveyor comprises a plurality of scraper pairs, a link unit is arranged in the middle of the adjacent scraper pairs, transmission holes are arranged at both ends of the adjacent scraper pairs, a rope-connected transmission unit is arranged at the transmission hole, a clamping hole for clamping a steel rope is arranged at one end of the rope-connected transmission unit, a transmission rod is arranged at the other end of the rope-connected transmission unit, the transmission rod is perpendicular to the conveying direction of the scraper conveyor, the steering arc conveying section is provided with a paddle wheel transmission mechanism matched with the transmission rod, a reduction motor is arranged at the power input end of the paddle wheel transmission mechanism, a plurality of rolling support mechanisms are arranged between the upper conveying section and the lower conveying section, and the middle of the rolling support mechanism is rollingly matched with the link unit; The paddle wheel transmission mechanism comprises a paddle wheel, and the paddle wheel is provided with a plurality of paddle openings evenly distributed in a circular array along its edge, and the paddle openings are used for slidingly cooperating with the transmission rod, and one side of the paddle openings is an inclined surface, and the other side of the paddle openings is a stepped surface, and the distance from the stepped surface to the inclined surface decreases from the outside to the inside; The thumbwheel comprises a first thumbwheel and a second thumbwheel distributed axially, a convex lip is arranged on the opposite surfaces of the first thumbwheel and the second thumbwheel, the convex lip and the first thumbwheel and the second thumbwheel form a wheel groove, a buffer is arranged in the wheel groove, the buffer comprises a slip ring matched with the convex lip, a gear ring matched with the slip ring and the groove surface of the wheel groove is arranged in the wheel groove, a plurality of clamping teeth corresponding to the thumbwheel openings are arranged on the ring surface of the gear ring, annular grooves are arranged on both sides of the gear ring, a plate-shaped buffer spring is arranged in the annular groove, the buffer spring is a C-shaped structure and two connecting feet are arranged at both ends, and the two connecting feet are respectively connected to the gear ring and the thumbwheel.

2. The method for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies according to claim 1 is characterized in that: In step S4, the mining field model is divided into 10 meters for one-step mining and 8 meters for two-step mining. The mining field is divided into several mining fields for each layer, and the ore body contour is expanded according to the length distance to ensure that there is enough space for the layered connecting tunnels. Finally, the center line of the bottom plate of the segmented vein outer tunnel, the flat slope section, the uphill section, the downhill section, the segmented ore body and the segmented vein outer tunnel are generated according to the expanded ore body contour.

3. The method for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies according to claim 1 is characterized in that: The scraper pair includes two scrapers, and the scraper includes a main board. The end of the main board facing the link unit is provided with an end plate connected to the main board in a cross shape. The link unit includes a circular plate. The diameter of the circular plate is larger than the vertical width of the main board and larger than 1 / 3 of the length of the end plate. The circular plate is provided with pairs of holes, and the pairs of holes are connected to the end plates by countersunk bolts. The rolling support mechanism includes a pair of support bearing seats, a support shaft is provided between the support bearing seats, a support plate is provided in the middle of the support shaft, and the disk edge of the support plate is provided with a rolling support groove that cooperates with the circular plate.

4. The method for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies according to claim 3 is characterized in that: The transmission hole comprises a C-shaped portion and a straight-shaped portion connected to the C-shaped portion, and the rope-connected transmission unit comprises a C-shaped tube connected to the C-shaped portion, and both ends of the side opening of the C-shaped tube are provided with a plug plate portion that cooperates with the straight-shaped portion, and the end of the plug plate portion is provided with a column head, and one end of the column head is provided with a plug hole that engages with the gaps between the two plug plates. The C-shaped tube, the plug plate portion, the column head and the transmission rod are connected as a whole, and the end of the transmission rod is provided with a stepped limiting end plate, and both ends of the C-shaped tube are provided with a hollow connector threadedly connected to its tube wall. The clamping hole is arranged at the center of the hollow connector, and the end of the hollow connector is provided with a card groove radially connected to its side surface, and the card groove, the gap of the plug plate and the plug hole constitute a positioning groove, and a pair of positioning plates plugged in opposite directions are arranged in the positioning groove, and a pair of positioning tenons are arranged on the plate surface of the positioning plate, and the positioning tenons cooperate with the positioning holes arranged on the plug plate and the column head.

5. The method for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies according to claim 4 is characterized in that: A plurality of weight-reducing holes are provided on the first and second thumbwheels, bolt holes are provided in the weight-reducing holes, clamping bolts for connecting the first thumbwheel and the second thumbwheel are provided in the bolt holes, the cross-section of the wheel groove is an isosceles trapezoid, the spring surface of the buffer spring is parallel to the waist of the isosceles trapezoid after being clamped by the thumbwheel and the gear ring, and the buffer spring is spiral in a natural state and its spiral length is less than one circle.

6. The method for low-loss, safe and efficient mining of gently inclined polymetallic ore bodies according to claim 1 is characterized in that: The horizontal ore-discharging box and the upward ore-discharging box are provided with guide rails matched with the transmission rods.

Images