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Ejge Paper Styles 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.
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