Natural caving method of mass bin

Abstract

The method for once forming a groove of a natural caving method collecting groove is characterized by the following steps: setting cutting crossways on both sides of a drilling roadway according to the arrangement of a bottom structure of the natural caving method and the features and parameters of the collecting groove; arranging 3-4 rows of slot fan-shaped medium-length holes in the middle of the drilling roadway; arranging 4-5 rows of slot fan-shaped medium-length holes on both sides of the drilling roadway; taking the cutting crossways as free surfaces; sequentially initiating the slot fan-shaped medium-length holes according to the inclination angles of the blast holes from small to large, and initiating the blast holes with the same inclination angle together; forming a cutting groove after the blasting of the slot fan-shaped medium-length holes; taking the cutting groove as a free surface; sequentially initiating the slot fan-shaped medium-length holes; and once forming the natural caving method collecting groove. The method can reduce the engineering quantity and construction procedure of the cutting shaft, reduce the production cost, improve the construction efficiency, and has the advantages of ensuring sufficient compensation space for the slot and eliminating the influence of the pre-caved ore on the cutting and slotting operation, saving 200-450 thousand yuan for each collecting groove, saving 10 days for once forming the groove compared with multiple blasting, and obviously improving the operation efficiency.

Description

Technical Field

[0001] This invention relates to the field of underground mining technology, and in particular to a method for forming a ore-accumulating trench in one step using the natural caving method. Background Technology

[0002] The natural caving method mainly consists of a bottom layer and an ore-producing layer, connected by a caving trench. Currently, most mines using the natural caving method both domestically and internationally adopt a pre-bottom caving approach. This approach results in the caving trench being filled with caving ore at the top before excavation. Using traditional cutting and caving techniques, the caving ore fills the cutting shaft, and some ore even enters the drilling roadway and loading route through the cutting shaft. This not only affects charging, wiring, and blasting operations but also makes it difficult to form the trench in a single blast due to the encroachment on the bottom compensation space. Multiple blasting and ore extraction cycles are required to complete the formation of the caving trench. Furthermore, the construction of the caving trench cutting shaft in the natural caving method is more difficult than other mining methods, mainly in the following aspects: ① When using manual drilling, the single-cycle advance is small, and the top is filled with caving ore, resulting in poor safety and reliability during breakthrough; ② Due to the caving ore at the top, a single-shaft drilling scheme is not suitable for raise drilling. Multiple small shafts need to be drilled as free faces, and then the trench is formed by blasting enlargement. This method has drawbacks such as numerous procedures, long construction period, and high production cost. To address the characteristics of the natural caving method for ore accumulation trenches and the shortcomings of conventional trenching methods, a one-step trenching method for natural caving ore accumulation trenches is proposed.

[0003] Our research group searched the database and found no prior reports of a method for forming a mineral accumulation trench in one step using the natural caving method.

[0004] Therefore, it is of great significance to develop a method for one-time formation of mineral accumulation trenches using the natural caving method. Summary of the Invention

[0005] The objective of this invention is to overcome the shortcomings of the prior art and provide a method for one-time formation of mineral accumulation trenches using the natural caving method. This method can reduce production costs, improve construction efficiency, and is also mature, effective, and easy to promote and apply.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] The method of forming a caving trench in one step using the natural caving method involves setting up cutting cross passages on both sides of the middle of the drilling roadway, based on the layout of the bottom structure and the characteristics and parameters of the caving trench. Within the drilling roadway, 3-4 rows of slotted fan-shaped medium-deep holes are arranged in the middle, and 4-5 rows of widening fan-shaped medium-deep holes are arranged on both sides. Using the cutting cross passages as the free surface, the slotted fan-shaped medium-deep holes are detonated sequentially according to the borehole inclination angle, with boreholes of the same inclination angle detonated simultaneously. After the slotted fan-shaped medium-deep holes are blasted, a cutting groove is formed. Then, using the cutting groove as the free surface, the widening fan-shaped medium-deep holes are detonated row by row, forming the natural caving caving trench in one step. This method reduces the amount of work and construction steps required for cutting the riser, lowers production costs, and improves construction efficiency. The specific process steps and conditions are as follows:

[0008] A. The natural caving method first completes the construction of the ore extraction roadway, ore loading access roadway, rock drilling roadway, cutting cross roadway and bottom pulling roadway, which can improve the working face and compensation space for cutting and grooving operations;

[0009] B. The current natural caving method involves drilling, blasting, and ore extraction in the caving tunnel according to the determined caving cross section, until the caving front line is twice the distance between the ore accumulation channel and the ore accumulation channel of the caving operation.

[0010] C. When using a medium-deep hole drilling rig in the drilling roadway, the blast holes of the slotted fan-shaped medium-deep holes and the expanded fan-shaped medium-deep holes are completed according to the designed blast hole diameter, opening position, angle and depth. The blast holes of the slotted fan-shaped medium-deep holes No. 1-4 and No. 14-17 should exceed the outline of the pillar by a certain distance. The bottom of the holes of No. 5-13 and all the expanded fan-shaped medium-deep holes should be 0.5-1.0m away from the upper collapsed area.

[0011] D. Use a charging trolley or charging device to charge all boreholes at once. When charging, place a detonating charge at the bottom of the hole. The detonating charge contains two detonators. The detonator segments of boreholes with the same inclination angle in the grooved fan-shaped deep holes are the same. The segments of boreholes with different inclination angles are increased by one segment. The segments of detonators of boreholes in the same row in the widened fan-shaped deep holes are the same. The segments of detonators from the row closest to the cutting groove are increased by one segment based on the largest segment of the detonator in the grooved fan-shaped deep holes (boring hole No. 9).

[0012] E. Two detonating cords are used to tie one detonator lead wire to each blast hole according to the standard. The ends of the two detonating cords and two detonators of the same section are tied together to form a double-circuit detonation network. After safety warning and receiving the detonation command, the detonation is carried out to form a ore accumulation trough in one go.

[0013] Compared with the prior art, the present invention has the following advantages or effects:

[0014] Because there is no need to cut a riser and it is not pre-connected to the bottom layer, the ore that collapses from the upper part will not enter the cutting shaft and the ore extraction level roadway. Therefore, it can ensure that the ore channel has sufficient compensation space and eliminate the impact of the pre-collapsed ore from the upper part on the cutting and channeling operation, allowing time for the ore accumulation channel to be completed in one go. At the same time, since the setting of the cutting riser is eliminated, the bottom structure of the natural caving method is different, and the depth of the cutting riser is different, generally 10m to 15m. The cost of each meter of cutting riser is 20,000 to 30,000 yuan. Therefore, each ore accumulation channel can save 200,000 to 450,000 yuan in costs. In addition, since the channel can be completed in one go without cutting a riser, about 7 days of drilling time can be saved. Compared with multiple blasting channels, about 3 days can be saved. Each ore accumulation channel can save a total of about 10 days, so the operation efficiency is significantly improved. Attached Figure Description

[0015] Figure 1 This is a front view of the bottom troughing method of a one-time troughing method for ore accumulation troughs proposed in this invention.

[0016] Figure 2 for Figure 1 The diagram shows a side view of the bottom trenching method in the natural caving method for forming ore-accumulating trenches in one step.

[0017] Figure 3 for Figure 1 The diagram shows a plan view of the natural caving method for forming a mineral accumulation trench in one step.

[0018] The symbols in the attached diagram represent:

[0019] 1. Rock drilling tunnel 2. Cutting cross passage 3. Grooving fan-shaped medium-deep hole 4. Enlarged grooved fan-shaped medium-deep hole 5. Bottom-pulling tunnel 6. Prematurely collapsed ore 7. Mine pillar 8. Mine pillar outline 9. Ore loading entrance 10. Mine exit tunnel

[0020] The present invention will now be described in further detail with reference to the accompanying drawings. Detailed Implementation

[0021] As attached Figures 1-3As shown, the method of forming a ore-accumulating trench in one step using the natural caving method involves setting up cutting cross passages (2) on both sides of the middle of the drilling tunnel (1), arranging 3-4 rows of slotted fan-shaped medium-deep holes (3) in the middle of the drilling tunnel (1), and arranging 4-5 rows of widening fan-shaped medium-deep holes (4) on both sides of the drilling tunnel (1). With the cutting cross passage (2) as the free surface, the slotted fan-shaped medium-deep holes (3) are detonated sequentially according to the borehole inclination angle from small to large. Boreholes with the same inclination angle are detonated together. After the slotted fan-shaped medium-deep holes (3) are detonated, a cutting groove is formed. Then, with the cutting groove as the free surface, the widening fan-shaped medium-deep holes (4) are detonated row by row to form a natural caving ore-accumulating trench in one step. This method can reduce the amount of engineering work and construction procedures of the cutting riser, reduce production costs, and improve construction efficiency. The specific steps and conditions are as follows:

[0022] A. The natural caving method first completes the construction of the ore extraction roadway (10), ore loading roadway (9), rock drilling roadway (1), cutting cross roadway (2) and bottom pulling roadway (5), which can improve the working face and compensation space for cutting and grooving operations;

[0023] B. The current natural caving method involves drilling, blasting and ore extraction in the caving tunnel (5) according to the determined caving cross section, until the caving front line is twice the distance between the ore-gathering trough and the ore-gathering trough of the caving operation.

[0024] C. When using a medium-deep hole drilling rig in the drilling roadway (1), the drilling rig completes the slotted fan-shaped medium-deep holes (3) and the widened fan-shaped medium-deep holes (4) according to the designed blast hole diameter, opening position, angle and depth. The blast holes 1-4 and 14-17 of the slotted fan-shaped medium-deep holes (3) should be a certain distance beyond the pillar outline (8). The bottom of the blast holes 5-13 and all the widened fan-shaped medium-deep holes (4) should be 0.5-1.0m away from the upper collapsed area.

[0025] D. Use a charging trolley or charging device to charge the explosives and complete the charging of all the boreholes at once. When charging, place the detonating charge at the bottom of the hole. The detonating charge contains two detonators. The detonator sections of the boreholes with the same inclination angle in the grooved fan-shaped deep hole (3) are the same. The sections of the boreholes with different inclination angles are increased by one section in turn. The detonator sections of the boreholes in the same row in the grooved fan-shaped deep hole (4) are the same. The detonator sections of the row closest to the cutting groove are increased by one section in turn based on the largest section of the detonator (boring hole No. 9) in the grooved fan-shaped deep hole (3).

[0026] E. Two detonating cords are used to tie one detonator lead wire to each blast hole according to the standard. The ends of the two detonating cords and two detonators of the same section are tied together to form a double-circuit detonation network. After safety warning and receiving the detonation command, the detonation is carried out to form a ore accumulation trough in one go.

[0027] The method of the present invention can be further described as follows:

[0028] The removal of the cutting well avoids the impact of ore (6) that collapses prematurely in the bottom roadway (5) on the cutting and grooving work, which can reduce the amount of work and construction procedures of the cutting well, reduce production costs and improve construction efficiency.

[0029] Cutting cross passages (2) were added on both sides of the middle of the rock drilling roadway as the free face for the initial blasting. The width of the cutting cross passages (2) is slightly larger than the width of the cutting groove, and the depth is about 2m. This can reduce the amount of work by 50-70%, reduce the impact on the integrity of the pillar (7), and improve the safety and stability of the bottom structure.

[0030] The bottom of the deep hole (3) in the grooved sector extends a certain distance beyond the outline (8) of the pillar, forming a cutting groove slightly larger than the cross-section of the ore accumulation groove. This avoids the ore accumulation groove from not being fully formed due to clamping effect. At the same time, the cross-section of the cutting groove is smaller than the cross-section of the cutting groove in the known grooving method, which can also reduce damage to the pillar (7) and is conducive to the stability of the bottom structure.

[0031] The deep hole (3) in the grooved fan shape is detonated starting from the blast hole with a small angle. The ore body that comes into contact with the pre-collapsed ore (6) above is detonated later. Because the time interval of the micro-differential blasting is short, it can avoid the pre-collapsed ore (6) above from entering the ore accumulation range too early and affecting the cutting and grooving operation.

[0032] Before the cutting and grooving operation is carried out, the pre-collapsed ore (6) at the top cannot encroach on the space of the cutting shaft and the bottom project, so that the roadway projects such as the rock drilling roadway (1), the cutting cross roadway (2) and the ore loading roadway (9) can form sufficient compensation space to assist the ore accumulation trough to be formed in one go.

[0033] Cutting wells do not require construction, and the cutting groove formation and trench expansion blasting operations do not need to be carried out in multiple stages, which can reduce the number of work cycles, reduce costs and improve efficiency.

[0034] As described above, the present invention can be well implemented. The above embodiments are only the best implementations of the present invention, but the implementation of the present invention is not limited to the above embodiments. Other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention should be considered equivalent substitutions and are all included within the protection scope of the present invention.

Claims

1. A method for forming a mineral accumulation trench in one step using the natural caving method, characterized in that... Cutting transverse tunnels (2) are set up on both sides of the middle of the rock drilling tunnel (1). Three to four rows of slotted fan-shaped medium-deep holes (3) are arranged in the middle of the rock drilling tunnel (1), and four to five rows of widening fan-shaped medium-deep holes (4) are arranged on both sides of the rock drilling tunnel (1). With the cutting transverse tunnel (2) as the free surface, the slotted fan-shaped medium-deep holes (3) are detonated in sequence according to the inclination angle of the blast holes from small to large. The blast holes with the same inclination angle are detonated together. After the slotted fan-shaped medium-deep holes (3) are blasted, a cutting groove is formed. Then, with the cutting groove as the free surface, the widening fan-shaped medium-deep holes (4) are detonated row by row to form a natural caving ore accumulation trench in one go. The specific process steps and conditions are as follows: A. To improve the working face and compensation space for cutting and grooving operations, the natural caving method first completes the construction of the ore outlet roadway (10), ore loading roadway (9), rock drilling roadway (1), cutting cross roadway (2) and bottom haulage roadway (5); B. The current natural caving method involves drilling, blasting and ore extraction in the caving tunnel (5) according to the determined caving cross section, until the caving front line is twice the distance between the ore-gathering trough and the ore-gathering trough of the caving operation. C. When using a medium-deep hole drilling rig in the drilling roadway (1), the drilling rig completes the slotted fan-shaped medium-deep holes (3) and the expanded fan-shaped medium-deep holes (4) according to the designed blast hole diameter, opening position, angle and depth. The blast holes 1-4 and 14-17 of the slotted fan-shaped medium-deep holes (3) should be a certain distance beyond the pillar outline (8). The bottom of the blast holes 5-13 and all the expanded fan-shaped medium-deep holes (4) should be 0.5-1.0m away from the upper collapsed area. D. Use a charging trolley or charging device to charge the explosives and complete the charging of all the blast holes at one time. When charging, place the detonating charge at the bottom of the hole. The detonating charge contains two detonators. The detonator segments of the blast holes with the same inclination angle in the grooved fan-shaped deep hole (3) are the same. The segments of the blast holes with different inclination angles are increased by one segment in turn. The detonator segments of the blast holes in the same row in the grooved fan-shaped deep hole (4) are the same. The segments of the detonators in the row closest to the cutting groove are increased by one segment in turn based on the largest segment of the detonator in the grooved fan-shaped deep hole (3). E. Two detonating cords are used to tie one detonator lead wire to each blast hole according to the standard. The ends of the two detonating cords and two detonators of the same section are tied together to form a double-circuit detonation network. After safety warning and receiving the detonation command, the detonation is carried out to form a ore accumulation trough in one go.

2. The method according to claim 1, characterized in that: The setting of the cutting well was removed to avoid the impact of the ore (6) that collapsed prematurely in the bottom roadway (5) on the cutting and slotting work.

3. The method according to claim 1, characterized in that... Cutting cross passages (2) were added on both sides of the middle of the rock drilling tunnel as the free face for the initial blasting. The width of the cutting cross passages (2) is slightly larger than the width of the cutting groove, and the depth is 2m.

4. The method according to claim 1, characterized in that: The bottom of the deep hole (3) in the grooved fan shape extends a certain distance beyond the outline line (8) of the ore pillar, forming a cutting groove slightly larger than the cross-section of the ore accumulation groove.

5. The method according to claim 1 or 4, characterized in that: The deep hole (3) in the grooved fan shape is detonated starting from the small-angle blast hole and then detonates after contacting the ore body that has been pre-collapsed above (6).

6. The method according to claim 1, characterized in that... Before cutting and grooving operations are carried out, the pre-collapsed ore (6) at the top must not encroach on the space of the cutting well and the bottom project, so as to assist in the one-time formation of the ore accumulation trough.

7. The method according to claim 1 or 6, characterized in that: Cutting the well requires no construction work, and the cutting groove formation and blasting operations for widening the groove do not need to be carried out in multiple stages.

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