1 Overview Anqing Copper Mine is a copper iron mining beneficiation mountain under a large pit, designed daily mining capacity of 3500 tons. The ore body has an elevation of -180 ~ -780m, which is the contact skarn type iron-copper deposit. The surface is farmland and village. The elevation is about +50 m, and the ore body is going from 125° to 305°. The main car is southwest, and some tend to be northeast. The main part is steeply inclined ore body. The length of the ore body has been controlled to be about 760m and the average thickness is 40~50m. The high-stage large-diameter deep-hole recovery mining method is the main mining method for mining, and the vertical ore body orientation of the stope is arranged, and the mining room and column are harvested in two steps. The stope is subjected to section rock drilling and two-stage continuous mining. The height of the mining stage is 120 m. The rock drilling equipment is Simba-261 type down-the-hole drilling rig with a diameter of 165 mm. The ST-5C shovel is used for mining. 3.8 m3. After the implementation of the stope, the one-time filling is shown in Figure 1. The structure of the stope of the Anqing copper mine is shown. Fig.1 Schematic diagram of high-stage large-diameter deep hole mining in Anqing Copper Mine Fig. 1 Schematic of high level large-diameter deep hole mining in Anqing Copper Mine 2 Mining technology 2.1 mining cutting engineering 2.1.1 Rock drilling engineering The rock drilling project is the working place for rock drilling and blasting. At present, the common layout of the Anqing copper mine is the roadway type. The outstanding advantages of this arrangement are the small amount of excavation work, less support engineering, easy control of the stope boundary, convenient filling and closing, short working time and safe operation of personnel. 2.1.2 Mining project The mining of the stope is a trackless mechanized operation, and the equipment is a ST-5C scraper. The bottom structure of the stope has a flat bottom type and a sulcus type, and the mining method has a single side type and a double side type. Practice has proved that the bottom structure of the V-shaped trench double-sided approach is the best. This engineering structure is widely used in various stopes. 2.2 Stope hole Under certain rock conditions, explosives with different properties and different blasting parameters have great differences in blasting and crushing effects. In order to meet the needs of large-diameter deep-hole mining in Anqing Copper Mine, single-hole blasting funnel test and double-hole same-stage blasting were carried out using EL-102#, RJ-2# ordinary emulsified explosives, 2# rock explosives and ammonium explosives. Simulation test. Through comparative analysis, the common emulsified explosives were used for blasting and lateral blasting. The hole parameters of the stope were determined according to the blasting funnel test results. The hole parameters of the blasthole in the middle of the mining site were 3.0 m×3. .0 m. In order to effectively control the boundary of the stope, the side row holes are subjected to smooth blasting, and the parameters of the hole net are taken as (2.2 to 2.5) m × (2.0 to 2.2) m (resistance line × hole spacing). The hole to the stope boundary is 0.5 m. The sides of the mining column are filled with filling holes. The principle of the hole in the mining column is to protect the filling body on both sides, to minimize the fragmentation of the filling body caused by the super-explosion and the fall of the filling body caused by the excessive blasting scale. . The hole in the middle of the mining pit adopts the hole mesh parameters of 3.0 m×3.0 m, and the side row holes are based on the theory of reinforced loose blasting. The hole parameters of 2.0 m×2.0 m are used to strengthen the loose blasting. The side row holes are 1.5 to 1.7 m from the filling body boundary. 2.3 stop blasting 2.3.1 Method of collapse In order to effectively control the blasting scale, the mining blasting is carried out to ensure the stability of the stope, and the collapse mode of the mining site is “small section VCR method slot + segmental side collapseâ€. The VCR method has a groove range (3 m × 3 m) to (5 m × 5 m), and the segmental lateral collapse height is controlled at 10 to 15 m. The mining pit adopts a large section VCR method (10 m × 10 m) and a small section lateral collapse (around 6.0 m). 2.3.2 Charge structure The charging structure of the VCR method boring blasting, the lower part of the blasthole is blocked 0.5-0.8 m, the medicine package is 30 èš; the upper part is blocked 0.8-1.0 m. The charging structure of the middle hole of the stope is 0.8~1.0 m in the lower part, 20~25 kg in the single layer, and 0.8~1.0 m in the air isolation plug. The upper part of the sand is filled with 1.2~1.5 m; the side hole of the mining room is smooth blasting, and the radial uncoupled charge is used. The uncoupling parameter is 3. 0~3.3, the line charge density is 5.70. ~ 6.25 k∥m. The lower part is blocked 0.6~0.8 m, the single layer is 3~5 kg, the air interval is 0.4~0.6 m, and the upper block is 0.8~1. 0 m: the side hole of the quarry is used Strengthen loose blasting, blasting exponential function F(IV)=0.86, resistance linearity=2.0 m, hole spacing B=2.0 m, air gap 0.6 m, single layer dose 3 kg, explosive The unit consumption is 0.25 k∥t, the lower part is blocked by 0.5 m, and the upper part is blocked by 0.6. 2.3.3 initiation sequence After years of scientific experiments and production practices, in order to effectively improve the blasting effect and control the boundary of the stope, the middle blasthole of the stope is detonated by group holes. 2 to 3 rows are one stage, the middle hole first blasts, and the side row holes lag. The side row holes are detonated by "inline shape", and the number of detonating holes is 3 to 4, which can reduce the damage of the side row hole blasting to the boundary of the stope. 2.4 Retaining blasting and strengthening mining The high-stage large-diameter deep-hole mining method has the characteristics of large stope, long mining time and poor stability of the stope. Therefore, during the blasting period, the mining ore mining stope should be controlled by the mining blasting control to stop the mining, and the ore under the blast should be used to support the “surrounding rock†to ensure the stability of the mining site during the blasting process. After the blasting of the stope is completed, the organization will carry out intensified ore mining, and shorten the exposure time of the open space in the stope, so that the stope can be filled as soon as possible to prevent the ore and the filling body from falling. 2.5 stope filling The high-stage stope requires high filling quality, especially the tailings cement filling in the mining yard, and the filling body should be stable when mining the mining yard. Therefore, during the filling process, from the preparation of the slurry, the transportation, the dewatering and solidification of the stope, and the required strength and self-supporting height of the filling body, it is not only a series of technological processes, but a systematic project. After years of scientific research and production practice verification, the filling system has 700 m. / Day (dry volume, a system) filling capacity, filling and conveying concentration of about 72%, the yard filling sand and sand ratio is based on the high-stage pillar mining process requirements, according to the stress distribution of the pillar mining field . The finite element analysis results show that at different heights of the mine, the tail rubber filling body adopts three different ratios of lime sand: 1:4, 1:8, 1:10. The test values ​​of the filling test pieces of different lime-sand ratios are shown in Table 1. Through the mining column mining practice, the tailings mixing rate is generally 3% to 5%, and the filling body does not have a large area of ​​collapse, and the self-standing state is good. Table 1 compressive strength at different concentrations and ratios Table 1 Compressive strength under different Concentration and mixture ratio 3 mining technical measures Objectively analyzing the stability of the stope is a prerequisite for the smooth recovery of the stope, and the technical level of the technical measures running through each recovery process is the key to the recovery work. In order to ensure the safe, smooth and economical application of the high-stage large-diameter deep-hole mining method to the mining and mining pillars, the Anqing copper mine has a stope structure, mining sequence, blasthole network parameters, collapse mode, blasting parameters, In-depth and meticulous technical research on the mining methods and filling processes, and some key technical measures are drawn from them. 1) The mining site adopts the VCR method for small-section troughing and segmental lateral collapse. The lateral collapse level is 10~15 m, and the maximum single-shot dose is controlled within 800èš. The blasting technology such as smooth blasting is applied to the boundary of the stope, which can effectively control the regularity of the boundary of the stope and control the regularity of the backfill. 2) The mining pit adopts the VCR method for large-section troughing and small-section lateral collapse. The segmentation height of the lateral collapse is about 6 m, and the maximum single-shot dose is controlled within 300 kg. The blasting technology such as strengthening loose blasting is implemented at the stope boundary, which can effectively reduce the direct impact of blasting on the filling body. 3) Optimize the parameters of rock drilling and blasting, charge the structure, select a reasonable initiation sequence, and reduce the damage of the blasting to the regularity of the stope. 4) During the mining process of mining and mining queuing, the mining blasting shall be strictly carried out to reduce the exposure height of the ore and filling body directly in the blasting process of the stope. That is to say, during the blasting period, the amount of ore discharged from the stope is strictly limited, and the stress state of the ore and backfill is changed by the ore pile and the damage of the stability of the ore and backfill by the blasting of the stope is weakened, thereby ensuring the recovery of the mine and the pillar. The stability of the stope in the process. 5) In order to shorten the exposure time of the goaf, reduce the fall of the ore and backfill caused by the exposure of the goaf, and strengthen the mining. After the mining of the stope is completed, the intensive filling is carried out. After the filling of the stope is half, the stope is basically stable. 6) When filling, ensure the height of sand surface of certain sand silo, ensure the concentration of pulping, strictly control the proportion of sand and sand and the filling concentration through automatic control instrument. Multi-point feeding, multi-point dewatering, strictly prohibiting the introduction of water and washing water into the mining field to reduce segregation and ensure the uniformity of the filling body. 7) Strengthen the filling process management, strengthen the tail sand level, filling concentration, filling strength, cement quality testing to ensure the filling quality. 4 Conclusion The practice shows that the mining technology and the quality of the filling body are the key to restrict the success or failure of the mining in the high-stage stope. The stability of the stope is the core of the mining stoppage. Only the effective blasting technology can realize the regularity and stability of the stope. Under the premise of ensuring the quality of the filling body, the smooth recovery of the stope can be realized. After years of scientific research and production practice, Anqing Copper Mine has explored a relatively complete production management and production technology system, laying a solid foundation for the wide application of high-stage large-diameter deep-hole mining method in Anqing Copper Mine. references [1] Liu Daokun. High-stage stope stability analysis and mining technology research [J]. Non-ferrous metal (Mine Section), â„¢ 2008 60 (.3): 8-11. [2] Xia Qian, Wei Ming. Research on blasting technology of high-stage large-diameter deep hole mining method "J1. Non-ferrous metals, 2000, 52 (2): 3 ~ 5 [3] Xie Yuan. Chen Yueda, Ge Shugao, et al. Experimental study on high-stage mining technology of Anqing Copper Mine [J]. Mining and Metallurgy, 1997, 6 (1): 1-2. [4] Zou Xianji, Wei Ming. Analysis of factors affecting stability of high-stage large-diameter deep-hole stope and technical measures for mining [J]. Mining Technology, 2005, 5(3): 25-28. 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Research on mining technology of high-level stope in underground mine