Influence Factors and Technology to Improve the Mining Productivity by Using Filling Mining Method
Dong Peixin Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 10083, China; Beijing Urban Construction Exploration & Surveying Institute Beijing 100101, China e-mail: [email protected]
Yang Zhiqiang Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 10083, China; Jinchuan Group Co., Ltd, Jinchang, Gansu 737100, China e-mail: [email protected]
Gao Qian Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 10083, China; e-mail: [email protected], the corresponding author
Xiao Bolin Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 10083, China; e-mail: [email protected]
ABSTRACT The Longshou mine is one of the three main production bases in Jinchuan co. LTD. After decades of excavation, high grade ore is nearly exhausted and lean ore is becoming the main mining object. Improving the mining productivity and achieving scale benefits are important approaches to lean ore exploitation. This paper, focused on lean ore exploitation in the mine area Ⅲ of Jinchuan Nickel mine, carrying out key technology research on improving the production capacity of backfill mining method. Firstly, for the purpose of utilizing large scale mining equipment, it starts with the parameter optimization and stability analysis in large hexagonal cross-section approach, and then investigates the drifts optimal placement in the drift stoping. Secondly, it develops the mining processes of large hexagonal cross-section drift stoping method, blasting parameter optimization and control technology. Through trial and engineering application, not only it improves the backfill mining production capacity in lean Longshou mine, but to guarantees mining safety, thus achieves significant economic and social benefits. KEYWORDS: Longshou mine; Mining Project; Filling Mining Method; Influence factors
- 2599 -
Vol. 22 [2017], Bund. 07 2600
INTRODUCTION These Metal mineral resources in China mainly to lean ore, iron ore grade average is only 33%, lower than the world average of 11 percentage points. The main copper mine in China basically belongs to the low grade gold deposit, such as the Dexing copper mine, Dongguashan copper mine, Tongkuangyu copper mine and Pulang copper mine, etc. At present, some large copper grade is below 1%, the majority of mine ore grade is only 0.4%~0.7%. For example, the average grade of Tongkuangyu copper mine is 0.67%, and the Pulang copper mine is 0.522%.Jinchuan nickel mine, III and IV mine area is lean ore, and the average grade is only 0.4%~0.6%. After decades of mining, mining depth is increasing year by year, pressure increased. In addition, the lean ore rock is crushing, poor stability. Therefore, the large low grade deposit safety, high efficiency and low cost mining, are a tough choice of resource development in China. [1] Jinchuan nickel mine is the largest copper nickel sulfide deposits in China, and divided into 4 ore body. The mine area of and II are rich ore, but III and IV are lean ore. After decades of mining, the rich ore of I area are near the end, and lean ore has become the main exploration object. Lean ore reserves of west mining area in Longshou mine account for 93% of the total amount of the western mining area. The ore belongs to liquation injection type orebody, distributed in two pyroxene peridotite, harzburgite and olivine rock in the footwall of ultrabasic rock body. It Is an independent ore body formed by the geological structural action from I orebody faulted. The ore bodies are in stratiform, to 320 degrees~330 degrees, the tendency of south-west, the angle of 60 degrees~85 degrees. The orebody is 1100~1300m long, 10~200m wide, 10~175m thick, and the tendency length is 800m. Geological grade of ore body is 0.55%~0.60%. Because the III orebody experienced intense geological and tectonic action, joints are well developed, the ore rock is broken, and stability is poor, it belongs to typical large ore body of breaking rock [2]. Improving the lean ore production, reducing the mining cost, and realizing the scale benefit are the core problem of lean ore mining production. Jinchuan III orebodies exist different views in the selection of mining method [3], which are natural caving method of low cost and high production capacity, and filling mining method of the high cost and low production capacity. Therefore, Jinchuan mines have also carried out a lot of research. the III mine area is very broken and is difficult to control, and will cause serious dilution ore; at the same time, as the ore rock stability is poor, the bottom structure stability is difficult to maintain, and eventually natural caving method of original design is instead of fill mining method. However, the production ability of natural caving method is 1650000t, whether filling mining method can achieve or not, is an important task to research and solve in Longshou mine. Aiming at the production capacity problem of filling method in Longshou mine III lean ore, the problem analysis and countermeasure studying on mine construction to improve the mining production capacity are carried out [4]. Promoting large-scale mining equipment as the leading direction, a large section of hexagon stope mining, mining technology, blasting control technology and the study on the stability technology of mining and parameter optimization are carried out [5-9]. Through comprehensive research and production practice, the mining production efficiency has been greatly improved, technology and equipment are more matching, and mining production has increased steadily. According to the current mining production capacity, by 2014 the western mining area in Longshou Mine III orebody can amount to the produce production, implement the large-scale production target of lean ore backfill mining, and it not only improve Vol. 22 [2017], Bund. 07 2601 the mining economic benefits, but also realize the resource utilization of solid wastes, in order to protect the mine environment, and achieve significant social benefits.
THE PROBLEMS OF BACKFILL MINING IN LONGSHOU MINE ORE AREA
Large shovelling equipment utilization problem Strong mining, strong transport, strong backfill are a key link to improve the production ability of backfill mining. Therefore, the application of large-scale mining equipment is a premise condition to improve the filling mining production. In order to apply the jumbo and 6m3 scraper, the original small drift expands to the large section hexagonal stope, whose bottom width is 3.5m, waist width is7m, height is 6m. But as supporting facilities are not perfect, there are still 3 problems in the implementation process: (1) The scene is not equipped with a skid car inspection, and the stope height is up to 6m, so prying the top by man is very difficult, high labor intensity, but low efficiency; (2) In order to pry the ballast and charging, firstly blast hole at the bottom, and then provide medicine in the ore heap and blast hole of the upper part. It reduces the production efficiency and increases the blasting cost; (3) Hierarchical path height is half of the stope height, approach opening must be manually picking top, and the field usually takes 2 ~ 3 classes to complete opening and picking the top job of a route. Construction of low efficiency, poor security, is not conducive to the drill rig efficiency. So to further improve efficiency under the existing conditions, mining methods have to be further optimized.
Large cross section formation and stability control problem Jinchuan mine currently uses two mining methods of the rectangular approach and hexagonal approach. Rectangular construction is simple, and easy to control, but the stress condition is poor, go against the stability of route. The surrounding rock stress distribution of hexagonal approach is benefit to the mining stability, but the road cross section form puts forward higher requirements for blasting parameters optimization and control. Therefore, for the lean ore of mining conditions extremely unstable, large cross-section hexagonal formation and stability control problem, is a technology problem of the lean ore mining.
Continuous and steady production problems of filling method To improve the production scale of lean ore filling method, it is necessary to choose a mining method with high efficient extraction, fast transfer layer and low loss rate. Traditional single hexagon stope is small, fast, and flexible, but has some shortcomings in the process of actual production. After the end of mining in a single stope, from the last layer preparation, filling implement to layer opened and starting of mine out, it needs 20 days at least. During this period, the stope will lose the drawing ability, and seriously restrict the incensement of production capacity and equilibrium of ore supply. The existence of hexagon drift for traditional mining problems in Longshou Mine, we carry out a study of mining technology, including single layered road backfill scheme of arrangement, Vol. 22 [2017], Bund. 07 2602 double layered arrangement scheme, route section parameters, blasting parameters, disc area planning and integration, to meet the demands of large mining equipment and mining efficiency, and improve the production capacity of drift fill stoping.
DRIFT MINING AND HIERARCHICAL OPTIMIZATION LAYOUT Figures Aiming at the hexagon stope mining, hierarchical approach is half of the stope mining height, and need the top job in the mining process. It takes 2 ~ 3 classes at least to complete the top- picking job of a route, and person must stand in the ore heap when working. Exposure to the original rock, it exists a great security risk. At the same time, it cannot play a role of Jumbo continuous operation, and reduced the use efficiency of equipment. In order to put forward the single layered road backfill scheme and double layered road backfill staggered scheme.
Layout form of single layered Road The scheme is layered road backfill to half of the original height of the ore before filling, the lower layer begin, excavation in the lower part of the upper layered, after falling the backfill layer, form hierarchical channel with the same height of drift route. The hierarchical specification is rectangular, route is vertical layered arrangement, and the specification is hexagon drift. Each layer of mining area drops to the height less than half of the upper layer, after opening layer, mining the upper layer ore pillar, and adopting the sectional filling method after mining. Single layered road backfill arrangement scheme is shown in Fig.1.
Figure 1: Schematic diagram of single slicing drift backfill
When designing, a layered road is at the rock footwall or in the middle of ore body. Route is vertical layout, the length is about 50m, and layered route is used in each layer. The key is to ensure that the hierarchical road and route highly is consistent, and the hierarchical way is backfilled before the turning layer filling according to the height of the lower road. Backfill height is 2.5m, the layer height is 2.5m,and the height reaches 5m after the backfill layer falls. The layout is on the basis of a traditional small section of hexagon drift stoping scheme, through adjusting the stope layout and selecting engineering parameters, in order to adapt to the use of large mining equipment. It can realize multiple operations mining at the same time, expand the production capacity, and retain the characteristics of high strength, opening layer speed of the Vol. 22 [2017], Bund. 07 2603 hexagonal stoping. For a large and thick ore body, a mining field is divided into a plurality of recovery interval, and the stoping sequence are adjusted flexibly in the mining process, to realize multiple operations and continuous mining production, to increase the production capacity.
Layout form of double layered road Double layered arrangement scheme is that layout two layered road in each ore block, each layer only needs to use one, and can be used alternately between the upper layer and the lower one, need not backfilling in the ore transfer layer. Each panel area is divided into a number of stopes, and hierarchical road can be flexibly arranged in a vertical or along towards at the both ends of deposit Stope, the hierarchical specification is rectangular section. Route is vertical layered arrangement, and route specification is hexagonal level approach. Each layer decreases 2.5m than the upper one, mining the ore pillar of upper layer after opening layer, and filling is finished by using filling pipe linking into filling well reserved access. The layout scheme of double layered road is shown in Fig.2.
Figure 2: Schematic diagram of double slicing hexagonal cross-section approach
The stoping scheme is that each panel (length 100m, width to thickness of ore body) is divided into a number of stopes (length x width =50m * 50m, adopting the arrangement structure of double layered). Hierarchical road can be flexibly arranged in a vertical or along towards at both ends of stopes, hierarchical road specifications for 4m x 5m (width * height) of the rectangular cross section; Route is vertical layered arrangement, and the specifications is hexagonal level approach with the bottom width of 4m, the waist width of 6m, height of 5m. Each layer decreases2.5m than the upper layered bottom, filling one time each 2~4 routes after mining, filling is finished by using filling pipe linking into the return air shaft reserved. In the first mining process, must strictly control approach specification, direction and length according to the design; when beginning the second mining, mining is carried out according to the upper filling body position exposed. Route specification, direction, and length are controlled by the upper filling body, can greatly reduce the phenomenon of route super height, super width and direction deviating, and improve the production efficiency. Double layered arrangement scheme has the advantages of high flexibility, multitudes of mining work surface, suitable for large mining equipment, and retains the advantages of traditional hexagon mining strength, easy layout of stope in the irregular ore bodies, convenient construction, and fast opening layer. The core of single layered road backfill and double layered road alternate use is the layered road and route height arrangement. According to the actual situation of the ore body and mining Vol. 22 [2017], Bund. 07 2604 project, approach and hierarchical way can choose the layout in the direction along veins or through vein. Single layered projects approach can have a certain slope, and double layered road scheme is route level arrangement. The above two kinds of layered arrangement scheme are implemented by layered road and the same route height, do not need the top work in route opening operation, reduces the safety risk, realize continuous high-efficiency operation of mechanization, and improve the production efficiency.
PARAMETERS SELECTION AND STABILITY ANALYSIS OF HEXAGON DRIFT
In order to meet the application of large mining equipment, we carry out a large section of hexagon Stope Parameters Selection and stability study.
Parameters selection of large section hexagon Stope Hexagonal section parameter selection mainly considers two aspects of application of large equipment and route stability. The choice of parameters includes the slope angle of approach, height and width 3 parameters.
1) Two sides slope angle of hexagon drift The rationality of hexagonal section is mainly the analysis of the roof width influence degree by the sides slope angle. In the condition of drift space L fixed, sides slope angles decrease, roof width decreases, and the roof is more secure. Minimum slope of slope angle shall be determined as natural security ore angle of 42 degrees, because if the slope angle is less than the natural repose angle, it will bring difficulty to the ore haulage. In this case, the drift roof width is the minimum, mosaic structure of filling body is most obvious, and drift roof is the most secure.But this time, it makes slope angle of upper half backfill is minimum, if it is close to roof gradient of 0 degrees, it can be as variable top, and top slope safety or pillar bearing capacity are the worst. When the slope angle reaches a maximum of 90 degrees, the route for the rectangular section, drift roof width is the maximum. The existence of tensile stress zone, is prone to delamination, stress concentration coefficient of top slope angle area is big, and route two sides are prone to happen tensile stress damage and spalling wounding, and stability of roadway is poor.
To sum up, the rational slope angle is between 45°~90°,this interval has a special angle which is equilateral hexagon, and the corresponding slope angle is 60°. Equilateral hexagonal section in the hydrostatic stress field is the best section, but in the secondary stress field, the vertical stress acts on the route, and horizontal and vertical stress act on the edge of route. In order to improve the endurance of the vertical stress in pillars, should try to increase the thickness of the pillar, which is an increase of slope angle. Therefore, the slope angle should be more than 60°. Considering that the filling body forms a mosaic structure, increases the bearing capacity of filling body, slope angle should not more than 70°, so the slope angle should be chosen between 60 °~70 °.
2) Hexagon drift section height Vol. 22 [2017], Bund. 07 2605
The Longshou Mine hexagon drift height, is not limited by mining equipment in ordinary mining area. Its height mainly considers the convenient construction reasonable height of manmade prying and the mining efficiency, so 4m is reasonable. But in the mechanical mining area, the height is 6m, which is mainly to ensure the mining equipment smoothly go through the stratification in the road. 6m approach has brought inconvenience to the construction and prying. Therefore, the appropriate height of machine mining stope should be 4~5m, the layout form of mining field using "the double layered arrangement scheme" and "single layered road backfill scheme", make the stratification height be consistent with the approach, and convenient to the using of large equipment.
3 )Hexagon drift section width The drift width is the space, if the distance is smaller, and the width of drift is smaller. When the route width is less than height, the long axis of inscribed (circumscribed) ellipse parallel to the vertical stress direction, which conducive to withstand the vertical stress, and make the roof stability condition well, but under the situation, the pillar is too weak, decomposition of roof of the vertical stress, and is not conducive to the decomposition of the vertical stress. If the distance is increased, the drift width is increased. When the drift width is more than the height, the long axis of inscribed (circumscribed) ellipse and vertical stress direction is vertical, and is not conducive to withstand the vertical stress, increases the tensile stress of the roof area, caused insecure hidden trouble. So should choose the route distance equal to or approximately equal to the route height, inscribed (circumscribed) ellipse is similar to the circular, which is most conducive to supporting the pressure (Fig.3) .At the same time, route width selection should also meet the requirements of the equipment transport. The width is most important for scraper, route width is too small, the bucket destroys the drift sides, which is easy to shovel out the bottom, make the inclined slope into a straight slope, and the approach is "convex" shaped structure. Spacing of the equipment and approach should be close to 1m, to be facilitated the equipment operation (Fig.4).
Fig. 3: The height to width ratio of hexagonal cross-section approach
Vol. 22 [2017], Bund. 07 2606
Figure 4: LHD and the approach’s height to width ratio
To sum up, under the normal mining conditions, hexagon drift parameters of Longshou west mining area: top and bottom width is 4m, the waist width is 6m, height is 5m. Large section hexagonal approach not only meet the use requirements of the mining equipment, but also benefit to the stope stability. The hexagon drift stope of adjustment is shown in the Fig.5.
Figure 5: Large scale hexagonal cross-section approach after adjustment
Stability analysis of hexagon stope In order to analysis the stability of large section hexagonal approach, based on geological research of mine project, carry out the stability analysis of large section stope by adopting FLAC software modeling, thus we obtain the following conclusions: (1) Hexagonal section reasonable parameters follow two proportional relationships: firstly, the ratio of route height and bottom width is 1.5 ~2.0, and take a small value as far as possible, to increase the roadside edge angle for ore self-slide, and ensure the scraper transport smoothly; secondly, the width radio of route waist and bottom is 1.2 ~ 1.3, and take a value less than 1.25 as far as possible. Height of 5m is suitable for double layered approach and single layered ore structure. (2) When the hexagon approach is large section hexagonal drift, whose top and bottom width of is 4m, waist width is 6m and height is 5m, the concentration coefficient of surrounding rock Vol. 22 [2017], Bund. 07 2607 stress is relatively small, the stability of stope is higher, so we can arrange double layered mining forms, to improve the mechanized production.
Formation of hexagonal section approach In view of the traditional hexagonal mining drawbacks, which is the cycle of false roof form is long, labor intensity is high, the method is put forward, which is in the first layer, every other section is made for mining and hexagonal shape is formed after mining in the second layer extraction, the third layer form the standard hexagonal. According to mining method features of the hexagon drift, combining with the special requirements of geological conditions of Longshou mine, the mining preparation ,cut and mining technique of the first layer, second layer and third layer are not identical. The first layer is the first mining hierarchical in the middle, bearing large stress, and the top is the original rock, adopting strengthening support of the semi arch section; The second layer is a transition layer, and responsible for the cohesion of standard hexagonal section route and first stratification; completely artificial roof is formed in the third layer, and hexagonal section recovery stage of false roof appears in the normal operation.
1) Stoping layout in the first layer The section specification of the first layer mining approach is 5.0m x 4.0m (width * height), the shape of the cross-section is the straight wall arch, layered cross section specification is 4.0m x 4.0m (width * height), and the shape of the cross-section is the straight wall arch. Hierarchical road adopts full section double sprayed anchor net support, the shotcrete layer thickness is 200mm; route adopts monolayer spray anchor net. Bolt use Φ18 screw steel, length of 1.8m, row spacing of 1m, mesh with φ6.5mm round steel spot and net with 150mm * 150mm, grid plate use steel plate of 200mm * 200mm * 10mm, and the shotcrete thickness is 200mm, the strength of C20.
2) Drift stoping layout in the second layer The second layer decreases 2.5m, through vein layered cross section specification is 5.0m x 4.5m (width * height), the route specification is 4.0m x 4.0m (width * height), and the shape of the section is straight wall semicircle. Before filling the route, the two pillars is opened, the position is below the first layer filling body, the depth is 1.0m, form a trapezoidal with bottom width of 4.0m, waist width of 6.0m. The specifications of layered road along veins is 4.0m*4.0m (width*height), the cross-section shape is rectangular. The ore backfill is finished before filling and thoroughly handling the clamped mine of the roof after opening the layer. Through vein layered road adopts full section double sprayed anchor net support, The monolayer sprayed anchor net support is used for the original rock below 2.5m when tunnelling along veins layered, the sprayed anchor net support has been carried out on stratification above 2.5m,and the plain spraying strengthening support is also used; the monolayer sprayed anchor net support is carried out in place of the route opening to the 5m segment position and the adjacent pillar, and the monolayer sprayed anchor net support is adopted in the vault part of 5m away. Strengthening the inspection of bolt grouting and the quality and safety condition of concrete construction in the operation process, if it is found that the concrete crack or delamination, timely use metal arch or erecting the shed support lift. Bolt is used with Φ18 screw thread steel hook bolt, length of 1.8m (with hook), row spacing of 1m, mesh usingφ6.5mm round steel spot and net with 150mm * 150mm. The shotcrete thickness is: the plain one with 50mm; single with 100mm; double layer with 200mm, and the strength with C20. Vol. 22 [2017], Bund. 07 2608
3) Drift stoping layout in the third layer Through vein layered section specification is hexagonal cross section with the top and bottom width of 4m, waist width of 6m, and height of 5m, two-side original rock with plain shotcrete supporting. The Route specifications is hexagonal cross section with top and bottom width of 4.0m, the waist width of 6.0m, height of 5.0m. According to the designed hole position, arrange and draw contour and calibrate the hole position. It is strictly forbidden to destroy route sides when shoveling, to ensure the specifications. After opening 5m in the route, the monolayer sprayed anchor net support is adopted in the pillars between the adjacent routes and the original rock of the 5m route opening segment, and the supporting parameters of spray anchor are the same as the above. In the formation process of artificial top, the second layer mining is the key of the route specification quality. The second gouge layer is the upper grey of the third layered route, when the third layered drift stoping mining, easily set the direction according to the gray sides. When the second layer direction is deviated, overbreaking or underbreaking, it is bound to affect the specification quality of the third layered route. By this method, the first layer construction is pure operation without false roof, the second layer construction only need the spraying anchor net support, and the work efficiency has been greatly improved, the third layer into normal false roof drift stoping, the formed time of false roof only needs about half of the traditional method, which laid the foundation for the early stope production.
CONTROL BLASTING TECHNOLOGY OF HEXAGONAL ROUTE In traditional hexagonal mining method, the route height is 6m.The facilities are not perfect, in the actual production process, the whole tunnel blasting is very difficult, usually carry out the up and down drilling blasting, the first explosion in the lower part, and drilling and blasting the upper part on ore heap, which increases one time of dust ventilation and auxiliary operation, reduces work efficiency, and increases the cost of blasting. Therefore, the hexagon stopes blasting parameters optimization and research on control blasting technology are carried on. Drift mining is similar to the tunnel caving, which has only one free surface, large wall rock clamping force, small single cycle blasting footage, less falling ore, and the low operation efficiency. The blasting effect worsens by the hard rock, which makes the cyclic footage even less than 1.5m, seriously affects the production efficiency, and increases the cost of production. In the blasting drilling operation, the auxiliary time is basically unchanged. If increase the cyclic footage, the marginal benefit is obvious. Therefore, it is an important guarantee for efficient mining to improve the single cycle footage and the single cycle caving amount. According to the actual situation of the western mining area and the orebody blastability, set the blasting test of different parameters. According to the orebody blastability, the test is briefly divided into difficult orebody test and highly explosive test. (1) Scheme one is the double slot of 2 inclined holes and 8 wedge holes. Figure 6 shows the scheme one of the blasting holes arrangement diagram. 1# hole upward, 2# hole downward incline. The angle of the holes and the working surface is 65 degrees~75 degrees, and the hole distance is 0.4m, which as initiating cut hole of the first step. Vol. 22 [2017], Bund. 07 2609
Throwing a few broken ore, mainly make ore loose, and create favourable conditions for the wedge cutting by using a detonator; Because from the top, by clamping force is more and more big, more difficult to detonate, and the horizontal distance of wedge holes become small. 3-10# wedge holes incline to the middle, which is 65 degrees~75 degrees with the working face. The horizontal distance of 3# and 7# hole is1.4m, and the 6# and 10# hole is1.0m.3~10# holes are for the second step blasting holes, form trough cavity, and create free surface for the subsequent explosion by using three detonators; Auxiliary holes using five detonators, and the peripheral holes use seven detonators; the distance between bottom and the bottom holes is 0.2m, the distance of top and the top holes is 0.4m, the distance of the upper periphery holes and the boundary is 0.3m ,and the distance of lower surrounding holes and the boundary is 0.2m. The distance of supplementary holes is 0.6~0.8m.
Figure 6: Layout of the blast hole
(2) Scheme two is 8 wedge holes cutting. The scheme two is less than two middle holes than scheme one, and the other parameters are the same. (3) Scheme three is 6 wedge holes cutting. Scheme three reduces two holes based on scheme two, the number of auxiliary holes and periphery holes is unchanged, and the auxiliary holes position adjustment, so that they are uniform distribution. According to the results of three test schemes, it shows that scheme one is best in hard ore, but scheme three is best in soft ore. According to the actual ore rock conditions, the optimization of blasting scheme makes the explosive consumption reduce 14.6%, the circulating footage increase 21.1%.
CONCLUSIONS In view of the Longshou Mine III lean ore body mining, the key technology research on improving the mining production capacity is carried out, thus obtain the following conclusions: (1)The development of new hierarchical arrangement makes the mining process more flexible. The study proposes that a single layered backfill arrangement and staggered arrangement scheme of double layered, changes the problem which stope hierarchical route can only be arranged in the through vein direction, and the stope must adopt retreat. By multidirectional arrangement of Vol. 22 [2017], Bund. 07 2610 cutting engineering, the mining field is divided into a plurality of recovery interval, realizes the separation of stope mining area, the preparation mining area and filling area, which makes the operation more flexible, work surfaces in a stope can increase substantially, and creat favorable conditions for improving the production capacity. At the same time, the hierarchical specification parameters are the same as route ones by adjustment. When the vein layered roof are abnormal, the adjacent route can be as hierarchical way after the vein layered roads are filled, which solves the problem that the hierarchical position cannot be changed in the traditional method. (2) Implementation of the same height of route and hierarchical way makes the mining production more safety and higher efficiency. It avoids the defects of route the manual drilling rock and top picking, reduces the operation links, and enhances the operation safety. It is convenient for continuous operation, and can fully play the advantage of large equipment. At the same time, it also effectively solves the problem that gun smoke in the upper part of route aggregate and cannot be discharged by natural ventilation in the traditional method, and often need to use the high pressure air. (3) Optimize the section parameters through numerical simulation and field test. Through numerical analysis, choose the hexagon route parameters as the top, bottom width of 4m, the waist width of 6m, and height of 5m. The route parameters match with the machine production equipments, and have high construction efficiency and good safety. (4) The rapid formation of artificial roof shortens the mining time, and makes the production capacity steadily improve. According to the mining method features of hexagon drift, and combine with the special requirements of geological conditions in Longshou mine, the mining preparation, cut and recovery are different of the first layer mining, second layer and third layer. Through the research, the first layer construction is top operation without false roof; In the second layer, only the top construction needs the spray anchor net support, and work efficiency has been greatly improved; In the third layer, transfer into normal false roof drift mining, the formed time of false roof is only about half of the traditional method, and lays the foundation for the stope advanced production, and the improvement of benefit. (5) Greatly enhance the standardization level of mining safety. The same height layout of approach and hierarchical road reduces the top pick link of route opening, realizes continuous operation, and avoids the security risks caused by the filling body damage of the top picking of or form of the clamped ore. Multidirectional arrangement of the cutting project, divides the stope into a plurality of mining areas, realizes the separation of mining areas, preparation mining areas and filling areas, reduces the mutual interference of filling operations and mining, and create good conditions for the standard improvement of mining areas. (6) Decrease the mining preparation and cut project, and improve the economic efficiency of lean ore. Every vertical height of 20m no longer drive or fill the air return way, use the existing system engineering, and make the filling return shaft connect to the filling pipe for filling, which reduces a lot of drivage, and shortens layer extraction cycle. Layered section of the traditional method is small, the tunneling unit explosive consumption is higher than the ones of drift stoping. After the height of hierarchical road and route is the same, the construction conditions are the same, and explosive consumption is reduced correspondingly. The west district can reduce tunneling amount 900m/5200m3 each layer, and save the mining cost of 3.8 million yuan; Reduce 15m every million tons, and reduce by 26%. According to the design capacity of 1.65 million t/a calculation, each year mining 2.8 layer, can save the mining cost of 10.64 million yuan / year. Vol. 22 [2017], Bund. 07 2611
REFERENCES [1] Liu Yuming. The innovation and development of the construction of large-scale mining enterprises[J], Mining Technology.2010,10(3):117-120. [2] Predictive modeling of geo-stress dis-tribution pattern in jinchuan undergrounding mine[J], Electronic Journal of Geotechnical Engineering. 2014,19w:6767-6773. [3] Dong Peixin, Yang Zhiqiang, Gaoqian, Zhang Zhanbin. Repair Design and Construction of Shaft Project in Jinchuan Nieck Mine. [J], Electronic Journal of Geotechnical Engineering 2015,20(11):4497-4505. [4] Xiao Yang, Qian Gao, Zhiqiang Yang,etc. Activator Proportion for a New Filling Cementitious Material of Full tailings in Jinchuan Mine. [J], Electronic Journal of Geotechnical Engineering. 2015,20(8):2097-2106. [5] Xiao Yang, Bolin Xiao, Renfeng Song,etc. Iron Tailings Gravitational Settling Law and Implementation. [J], Electronic Journal of Geotechnical Engineering. 2016,21(2):641-654. [6] Yao Weixin, Ba Duoheng,Meng Xianhua. Problem analysis and countermeasure research on mine construction of 5 million tons in Longshou Mine[J], Mining research and development.2009,29(6):101-105. [7] Qiao Dengpan, Zhang Zongsheng, Wangliang,etc. Experimental research on improving blasting efficiency of the hexagon route mining[J], China mining.2006,15(10):83-91. [8] Stability Analysis and Design of Open-pit Mine Slope in China[J], Electronic Journal of Geotechnical Engineering. 2014,Z2:10247-10266. [9] Longshou Mine of Jinchuan Corporation Ltd. Technology research on large-scale mining of low grade ore[R].2013.10.
© 2017 ejge
Editor’s note. This paper may be referred to, in other articles, as: Dong Peixin, Yang Zhiqiang, Gao Qian, and Xiao Bolin: “Influence Factors and Technology to Improve the Mining Productivity by Using Filling Mining Method” Electronic Journal of Geotechnical Engineering, 2017 (22.07), pp 2599-2612. Available at ejge.com.