A two-step mining method for upward continuous extraction

Abstract

The application provides a two-step mining method for upward continuous mining, which is divided into lower stope, middle stope and upper stope according to the mining structure and specific depth of a mine; the blast holes of the lower stope and the middle stope are constructed, after the blast holes of the lower stope and the middle stope are completely constructed, a large hole slot is formed to cut a shaft, the large hole slot is charged from an upper rock drilling chamber, and a segmented and layer-by-layer pulling method is adopted; the blasting is sequentially performed from the middle to the two sides, the blast holes of the lower stope are fully charged, the upper stope is charged, the charging boundary is controlled within a range of 45° angle with the floor, and the charging boundary is triangular, and the ore body within the triangular range of the lower stope and the middle stope is jointly mined; the ore drawing access of the middle stope is arranged in the original rock; the application arranges the ore drawing roadway and the access in the rock, improves the strength and stability of the ore drawing roadway and the access, and realizes safe mining production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of non-ferrous metal mine mining, in particular to a two-step mining method of upward continuous stoping. BACKGROUND

[0002] With the progress and development of mining technology, the filling mining method has been widely applied in China; the empty field subsequent filling body mining method is applied in many large non-ferrous metal mines in China due to large production capacity and high efficiency; in this mining method, the ore body is often divided into multiple panels, the stope in the panel is divided into one-step ore room stope and two-step ore pillar stope, the one-step ore room stope is first mined, and the cemented filling is carried out after mining; the two-step ore pillar stope is mined, and the micro-cemented filling is carried out after mining; when the ore body is thick and upward continuous stoping is carried out, the lower stope becomes a filling body, and the two-step stoping bottom structure needs to be arranged in the filling body; due to the fact that the strength of the filling body is far lower than the strength of the original rock, the stability of the roadway is greatly reduced, and the ore extraction efficiency is reduced; on the other hand, when the lower stope is a filling body, the upper stope often uses a flat bottom structure to extract ore, and a large amount of ore pile is left in the middle of the stope, the stope loss rate is high, and the mine benefit is affected.

[0003] A certain large low-grade copper mine in Anhui Province is continuously mined from bottom to top without leaving horizontal ore pillars, and the ore body is divided into-770m, -705m, -650m, -585m, -530m, -465m and-410m middle sections; the middle section ore body is divided into multiple panels, and the ore body in the panel is two-step mined, one-step mined ore room and two-step mined ore pillar; the one-step stope length is 80m, the width is 24m, and the height is 120m; the two-step stope length is 80m, the width is 30m, and the height is 60m. The mine uses a deep hole large diameter empty field subsequent filling mining method, one-step cemented filling, two-step micro-cemented filling, and three-step mining of the isolation pillar; during the one-step mining process of the mine, the two sides are original rocks, which is convenient for the arrangement of the bottom structure, and the stability of the bottom structure engineering is good; during the two-step mining process, the two sides are filling bodies, and the two steps are mined step by step upward in a single middle section; according to the conventional mining method, the bottom structure is arranged along the strike of the stope, the ore extraction roadway and the ore extraction access are constructed in the filling body, and the ore is extracted by using a flat bottom structure; due to the fact that the two-step stope width is large, a large amount of ore pile is often left in the middle area of the goaf, the ore pile height is about 15m, the ore quantity is about 34,000 tons, the grade is calculated at 0.56%, and the economic value of the loss is about 9 million yuan; therefore, in view of the two-step stope of the upper large stope structure parameter of the filling body of the mine, how to efficiently and safely mine with high recovery rate, a two-step mining method of upward continuous stoping is needed. SUMMARY

[0004] In view of the above problems, the application provides a two-step mining method for upward continuous stoping, which arranges the ore drawing roadway and the access in the rock, improves the strength and stability of the ore drawing roadway and the access, and realizes safe mining production.

[0005] To solve the above problems, the technical scheme adopted by the application is:

[0006] A two-step mining method for upward continuous stoping:

[0007] Step one, determination of the stope structure: according to the mining structure and specific depth inside the mine, the stope structure is divided into a lower stope, a middle stope and an upper stope;

[0008] Step two, determination of the bottom structure: when the lower stope of the mine is stoped, the bottom structure is located in the original rock, the bottom structure is arranged according to the prior art, and a symmetrical type of ditch type bottom structure is arranged along the stope direction, the symmetrical type of ditch type bottom structure is arranged on both sides of the mine ditch, and the ore drawing access and the ore drawing roadway are arranged symmetrically, and then the diameter of the blast hole is determined according to the environment and equipment of the stope construction;

[0009] Step three, slotting construction: after the blast holes of the lower stope and the middle stope are completely constructed, large hole slotting is performed to form a cutting shaft, which provides compensation space for blasting, the large hole slotting is charged from the upper rock drilling chamber, and a segmented and layer-by-layer pulling open method is adopted;

[0010] Step four, blasting construction: the blasting is sequentially blasted from the middle to the two sides, the blast holes of the lower stope are fully charged, after the charging of the lower stope is completed, the upper stope is charged, the charging boundary is controlled within the range of 45° angle with the floor, and the charging boundary is triangular, and the ore bodies in the triangular range of the lower stope and the middle stope are jointly stoped;

[0011] Step five, stoping and filling: after the ore bodies in the triangular range of the lower stope and the middle stope are stoped, the top is filled, and the filling pipe is arranged in the rock drilling chamber of the middle stope;

[0012] Step six, ore drawing access arrangement: after the triangular area at the bottom of the lower stope and the middle stope is filled, a non-symmetrical type of ditch bottom structure is formed at both ends of the middle stope by using a medium-depth blast hole, one boundary of the ditch bottom structure coincides with the original rock boundary on one side of the isolation pillar, so that the ore drawing access of the middle stope is arranged in the original rock, and the upper part of the eyebrow line part of the ore drawing access is all original rock, and the stability of the roadway is greatly improved;

[0013] Step seven, hole washing processing: the blast holes of the middle stope which are not charged are damaged during the stoping of the ore bodies at the bottom of the lower stope and the middle stope, and the blast holes of the middle stope which are not charged are washed, that is, all the blast holes are re-constructed by using the rock drilling jumbo, and the blocked ore and filling body in the blast hole are removed;

[0014] Step eight, recovery processing: after the middle stope hole washing is completed, the upper stope hole is continued to be constructed, the triangular ore body at the bottom of the middle stope and the upper stope is recovered together, and the recovery sequence is gradually recovered from one side of the stope to the other side;

[0015] Step nine, arrangement of ore drawing roadway and access: after the triangular ore body at the bottom of the middle stope and the upper stope is blasted, the ore is drawn from both ends of the bottom of the middle stope, the panel roadway in the bottom structure is used as the ore drawing roadway, and the ore drawing access is arranged in the original rock.

[0016] Preferably, in step two, the lower stope is constructed with a 165mm diameter hole, and after the lower stope hole construction is completed, the middle stope continues to be constructed with a 165mm hole.

[0017] Preferably, in step three, the lower stope slot penetrates the entire middle section, and after the lower stope slot is completed, the middle stope is then slotted, and the slot height is 20-25m.

[0018] Preferably, in step four, 140mm diameter emulsion explosive is used for interval charging, and 0.6-0.8m bamboo is used to fill between the emulsion explosives.

[0019] Preferably, in step five, the filling is performed with the help of the hole at the highest point in the triangular range of the middle stope, which is beneficial to the filling of the roof, the sand ratio is 1:11, and the filling body strength is required to be more than 1Mpa, so as to reduce the damage of the falling ore to the filling body during the recovery of the middle stope and reduce the dilution rate.

[0020] Preferably, in step nine, the ore drawing roadway and the access are arranged in multiple groups in parallel, the multiple ore drawing accesses are adapted according to the width of the mining, and the multiple ore drawing roadways and accesses are respectively arranged to mine the stope at each height, so as to improve the efficiency of mining and reduce the time cost; and the multiple ore drawing roadways and accesses are connected through connecting gentle slope channels, and the ends thereof share a channel, which can fully utilize the existing mine resources, ensure efficient mining of the stope, and reduce the time and resource cost.

[0021] Preferably, the first predetermined interval is staggered between the second ends of the two groups of ore drawing tunnels and the approaches, the second predetermined interval is staggered between the second ends of the two groups of ore drawing tunnels and the approaches, the second predetermined interval is greater than the first predetermined interval, and a predetermined angle is formed between the two groups of ore drawing tunnels; and the multiple groups of ore drawing tunnels and the approaches are sequentially arranged in a predetermined order, the bottom structure of the second end of each ore drawing tunnel and the approach is an undamaged original rock structure, which has good strength and bearing capacity and can meet the transfer and transportation of mining equipment inside the ore drawing tunnel and the approach; the first ends of the ore drawing tunnels and the approaches are close to each other, which can reduce the economic cost and time cost required for excavating the ore drawing tunnels and the approaches and the gentle slope channel, ensure the stability of the overall structure, improve the mining efficiency, and reduce the mining cost.

[0022] Preferably, after the bottom end of the stope is filled, the corresponding ore drawing approach is closed and filled together with the goaf, and the ratio of the ash and sand is not less than 1:7; because the two groups of ore drawing tunnels and the approaches are staggered at a predetermined angle, the interval between the second ends of the two groups of ore drawing tunnels and the approaches is greater than the interval between the first ends, and the bottom of the bottom end of the ore drawing tunnel and the approach is an undamaged original rock structure, which has strong stability and bearing capacity; the filling of the ore drawing tunnel and the approach only needs to concentrate on filling the position close to the first end of the ore drawing tunnel and the approach, and the strength thereof is ensured; and the first end of the ore drawing tunnel and the approach can be fully filled with part of the broken slag generated by blasting and the filling material transported into the stope.

[0023] The beneficial effects of the present application are:

[0024] 1. In the prior art, the two-step stope recovery, the ore drawing tunnels and the ore drawing approaches are arranged in the filling body, the stability of the tunnels is poor, the tunnels are prone to collapse and other accidents under excessive external force, and the safety is poor; in the prior art, the two-step recovery uses a flat bottom structure for ore drawing, and a large amount of ore pile is often left in the middle region of the goaf, and the loss rate of the ore is high; in the present application, the ore drawing tunnels and the ore drawing approaches are arranged in the original rock, the structure of the original rock is not damaged, the internal rock has high strength, the stability of the tunnels is greatly improved, the filling body is used to replace the ore, the loss rate of the stope is greatly reduced, and the economic benefit of the mine is greatly improved.

[0025] 2、By setting multiple groups of parallelly arranged ore drawing roadways and access roads, the continuous mining requirements of the lower stope, the middle stope and the upper stope can be met, and the ore drawing efficiency is improved; and by setting the distance between the second ends of the ore drawing roadways and the access roads to be greater than the distance between the first ends, the adjacent ore drawing roadways and access roads are staggered and form a predetermined angle, the stability of the ore drawing roadways and the access roads can be ensured by means of the rock structure of the mine itself, and the stability of the movement of the engineering machinery in the ore drawing roadways and the access roads is ensured; and after the bottom recovery, the corresponding ore drawing roadways are closed and filled together with the goaf, and the stability of the bottom structure can be further ensured. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 Layout plan of the bottom structure for the middle stope of the -705m level of the present application;

[0027] Figure 2 Cross-sectional view of the lower stope I-I of the present application;

[0028] Figure 3 Cross-sectional view of the middle stope I-I of the present application;

[0029] Figure 4 Cross-sectional view of the lower stope II-II of the present application;

[0030] Figure 5 Cross-sectional view of the II-II stope of the prior art;

[0031] Figure 6 Comparison diagram of the goaf boundary of the lower stope and the middle stope of the present application.

[0032] In the figure: 1, lower stope; 2, middle stope; 3, upper stope; 4, lower stope drilling chamber; 5, middle stope drilling chamber; 6, charged blast hole; 7, uncharged blast hole; 8, cutting raise formed by draw slot; 9, panel roadway; 10, ore drawing access road of the present application; 11, asymmetric ditch bottom structure; 12, filling body; 13, ore drawing roadway of the prior art; 14, ore drawing access road of the prior art; 15, residual ore pile in the middle region of the goaf of the prior art; 16, goaf detection boundary of the lower stope; 17, goaf boundary of the upper stope. DETAILED DESCRIPTION

[0033] The present application is further described below in conjunction with the drawings and examples.

[0034] Referring to the drawings Figures 1-6 A two-step upward continuous mining method

[0035] (1) The one-step stopes FZ106, FZ108 and FZ110 are recovered according to the prior art and are cemented and filled;

[0036] (2) Definition: -770m~ -705m F107 is the lower stope 1, -705m~ -650m F107 is the middle stope 2, -650m~ -585m F107 is the upper stope 3.

[0037] (3) When the lower stope 1 is mined, the bottom structure is arranged as a symmetrical trench type bottom structure along the stope direction according to the prior art, and the symmetrical trench type bottom structure is arranged with equal ore drawing passages and ore drawing roadways on both sides of the ore trench, which is convenient for centralized ore drawing.

[0038] (4) Combined with the existing drilling equipment of the mine, the lower stope 1 is constructed with a 165mm blast hole 7, and after the construction of the lower stope is completed, the middle stope 2 continues to construct a 165mm blast hole 7.

[0039] (5) After the blast holes 7 of the lower stope 1 and the middle stope 2 are all constructed, a large hole slot is formed to form a cutting shaft 8, the large hole slot is charged from the lower rock drilling chamber 4, and a segmented and layer-by-layer pulling open method is adopted, the slot of the lower stope 1 penetrates through the entire middle section, and after the slot of the lower stope 1 is completed, the slot of the middle stope 2 is then pulled, and the height of the cutting shaft 8 of the middle stope 2 is about 20-25m.

[0040] (6) The blasting is sequentially blasted from the middle region to both sides, the blast hole 6 of the lower stope 1 is fully depth charged, and according to the diameter of the blast hole, a 140mm diameter emulsion explosive (9kg per hole) is used for interval charging, in order to control the blasting effect, the emulsion explosives are filled with 0.6-0.8m bamboo. After the charging of the lower stope 1 is completed, the upper stope is charged, and the charging boundary is controlled within the range of 45° angle with the floor, forming a triangle. The ore bodies in the triangular range of the lower stope 1 and the middle stope 2 are jointly mined.

[0041] (7) After the ore bodies in the triangular range of the lower stope 1 and the middle stope 2 at the bottom are mined, the top is filled, the filling pipe is arranged in the rock drilling chamber 5 of the middle stope 2, and the filling is carried out through the blast hole at the highest point of the triangular region of the middle stope 2, which is beneficial to the filling of the top, the sand ratio is 1:11, and the strength of the filling body is required to be more than 1Mpa, so as to reduce the damage of the filling body caused by the caving of the ore rock during the mining of the middle stope, and to reduce the dilution rate.

[0042] (8) After the goaf of the triangular range at the bottom of the lower stope 1 and the middle stope 2 is filled and the top is connected, a non-symmetrical trench type bottom structure 11 is formed in the middle stope by using a medium-depth blast hole perpendicular to the stope direction at both ends of the middle stope, the boundary of the trench bottom structure coincides with the side of the original rock boundary of the isolation pillar, so that the ore drawing passage 10 of the middle stope 2 is arranged in the original rock.

[0043] (9) The undetonated blast hole 7 in the middle stope 2 is damaged during the mining of the ore body at the bottom of the lower stope 1 and the middle stope 2. The blast hole 7 is washed, i.e. re-drilled by the drill jumbo, to remove the clogged ore and rock in the blast hole and ensure the quality of the blast hole.

[0044] (10) After the washing of the blast hole 7 in the middle stope 2, the blast hole in the upper stope 3 is drilled. The triangular ore body at the bottom of the middle stope 2 and the upper stope 3 is mined together, and the mining sequence is from one side of the stope to the other side.

[0045] (11) After the blasting of the triangular ore body at the bottom of the middle stope 2 and the upper stope 3, the ore is mined from the bottom of the middle stope 2. The vein roadway 9 at the bottom of the structure is used as the ore mining roadway, and the ore mining access 10 is arranged in the original rock. The stability of the roadway is greatly improved. The ore mining roadway and the access are arranged in multiple groups in parallel. The multiple ore mining roadways are adapted to the mining width. The multiple ore mining roadways and the access are arranged to mine the stope at different heights, thereby improving the mining efficiency and reducing the time cost. The multiple ore mining roadways and the access are connected by the connecting gentle slope channel. The end of the multiple ore mining roadways and the access shares a channel. The existing resources of the mining area are fully utilized to ensure efficient mining of the stope while reducing the time and resource costs.

[0046] It is to be noted that the second ends of the adjacent two groups of ore mining roadways and the access are staggered by a first predetermined distance, and the second ends are staggered by a second predetermined distance. The second predetermined distance is greater than the first predetermined distance, and a predetermined angle is formed between the adjacent two groups of ore mining roadways. The multiple groups of ore mining roadways and the access are sequentially arranged in a predetermined order. The bottom structure of the second end of each ore mining roadway and the access is the original rock structure that has not been damaged, and has good strength and carrying capacity. The first ends of the ore mining roadways and the access are close to each other, which can reduce the economic and time costs of excavating the ore mining roadways and the access and the gentle slope channel, ensure the stability of the overall structure, improve the mining efficiency, and reduce the mining cost.

[0047] (12) After the mining of the bottom end of the stope is completed, the corresponding ore mining roadways are closed and filled. The ratio of the ash and sand is not less than 1:7. The second ends of the adjacent two groups of ore mining roadways and the access are staggered by a predetermined angle, and the distance between the second ends is greater than the distance between the first ends. The bottom of the bottom end of the ore mining roadways and the access is the original rock structure that has not been damaged. The filling of the ore mining roadways and the access only needs to be concentrated near the first ends of the ore mining roadways and the access to ensure sufficient strength. The first ends of the ore mining roadways and the access can be fully filled with part of the blast slag and the filling material transported into the stope.

[0048] (13) The rest of the stope above 650m uses this kind of scheme, and the continuous mining construction of the stope is completed.

[0049] The application is applied to upper and lower stope in the mine, the coincidence rate of the goaf boundary 16 of the lower stope and the goaf boundary 17 of the upper stope is high, which indicates that the ore loss rate of the two-step upper stope of the application is small. Through the comparison and cutting of the goaf model and the design model, the overbreak volume and the underbreak volume of the actual stope recovery are calculated, and the recovery index of the upper stope is obtained, as shown in the following table.

[0050] From the table, it can be seen that the recovery method of the two-step upper stope of the application can greatly reduce the loss rate of the stope, and reduce by 8 percentage points, and each two-step upper stope produces economic value of 8.5 million yuan, which is beneficial to improve the economic benefit of the mine.

[0051]

[0052] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A two-step mining method for upward continuous mining, characterized in that, Includes the following steps: Step 1, Determining the stope structure: Based on the mining structure and specific depth within the mine, it is divided into lower stope, middle stope, and upper stope; Step 2, Determination of the bottom structure: When mining the lower part of the mine, since the bottom structure is located in the original rock, the bottom structure is arranged in a symmetrical trench-type bottom structure along the mining direction according to the existing technology. The symmetrical trench-type bottom structure is that the ore-receiving trench is arranged with equal ore-exit access roads and ore-exit roadways on both sides. Then, the diameter of the blast holes is determined according to the mining environment. Step 3, slotting construction: After all the blast holes in the lower and middle mining areas are completed, large-hole slotting is carried out to form a cutting ceiling, providing compensation space for blasting. The large-hole slotting is loaded with explosives from the upper rock drilling chamber, and is carried out in sections and layers. Step 4, blasting construction: blasting proceeds from the middle to both sides in successive blasts. The blast holes in the lower stope are fully charged. After the lower stope is charged, the upper stope is charged. The charging boundary is controlled within a range that forms a triangle with a 45° angle to the bottom plate. The ore body within the bottom triangle range of the lower and middle stopes is mined together. Step 5, backfilling: After the ore body in the triangular area at the bottom of the lower and middle mining areas is backfilled, the backfilling pipes are arranged in the drilling chamber of the middle mining area. Step 6, Layout of the ore extraction route: After the bottom triangular area of ​​the lower and middle mining areas is filled and connected to the roof, an asymmetrical trench bottom structure is formed at both ends of the middle mining area using medium-deep blast holes. One boundary of the trench bottom structure coincides with the original rock boundary on one side of the isolation pillar, so that the ore extraction route of the middle mining area is arranged in the original rock, and the upper part of the ore extraction route eyebrow is entirely original rock, which greatly increases the stability of the roadway. Step 7, Hole Cleaning: The uncharged blast holes in the middle stope are damaged and blocked during the mining of the bottom ore body in the lower and middle stopes. Hole cleaning is carried out on the uncharged blast holes in the middle stope, that is, all blast holes are re-constructed using a rock drilling rig to remove the blocking ore and filling material in the blast holes. Step 8, Mining and Processing: After the blast holes in the central stope are washed, continue to construct blast holes in the upper stope. The triangular ore bodies at the bottom of the central and upper stopes are mined together, and the mining sequence is to gradually mine from one side of the stope to the other. Step 9, Arrangement of mining roadways and access routes: After the triangular ore bodies at the bottom of the central and upper mining areas are blasted, ore is extracted from both ends of the bottom of the central mining area. The roadways in the middle panel of this bottom structure serve as mining roadways, and the mining access routes are arranged in the original rock at both ends of the mining area.

2. The two-step mining method for upward continuous mining according to claim 1, characterized in that, In step two, the lower mining area is constructed with 165mm diameter blast holes. After the blast holes in the lower mining area are completed, 165mm blast holes will continue to be constructed in the middle mining area.

3. The two-step mining method for upward continuous mining according to claim 1, characterized in that, In step three, the lower stope trenching runs through the entire middle section. After the lower stope trenching is completed, the middle stope trenching is then carried out, with a trenching height of 20-25m.

4. The two-step mining method for upward continuous mining according to claim 1, characterized in that, Step four involves using 140mm diameter emulsion explosives spaced apart, with 0.6-0.8m bamboo poles used to fill the gaps between the emulsion explosives.

5. A two-step mining method for upward continuous mining according to claim 1, characterized in that, Step five involves filling the backfill using the blast holes at the highest point within the triangular area of ​​the central stope. This facilitates the backfill to reach the roof. The ash-sand ratio is 1:11, and the backfill strength is required to be above 1 MPa. This reduces the damage to the backfill caused by the ore and rock that collapses during the mining of the central stope and lowers the dilution rate.

6. A two-step mining method for upward continuous mining according to claim 1, characterized in that, In step nine, the ore extraction roadways and access routes are set up in multiple parallel groups, and the multiple groups of ore extraction access routes are adapted to the width of the mining area.

7. A two-step mining method for upward continuous mining according to claim 6, characterized in that, The two adjacent sets of ore extraction roadways and the second end of the access roadway are staggered by a first predetermined distance, and the second ends are staggered by a second predetermined distance, wherein the second predetermined distance is greater than the first predetermined distance, and the two adjacent sets of ore extraction roadways form a predetermined angle.

8. A two-step mining method for upward continuous mining according to claim 6, characterized in that, After the bottom of the mining area is backfilled, the ore exit roadway will be closed and filled together with the goaf, with the ratio of lime sand not less than 1:

7. The ore exit roadway will continue to serve as the intermediate transport roadway.

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