A mechanized strip mining method

Abstract

The present invention provides a mechanized strip mining method, including arranging a cutting uphill in the middle of a ore block, recovering the strip in two steps, performing cementation filling after the first step of recovery, and performing the second step of recovery after the filling body reaches a certain strength, including the following steps: setting up a riser drill in the middle level tunnel of the ore block, assembling a guide hole drill bit on the riser drill, drilling a guide hole in the lower middle level tunnel through the guide hole drill bit, and the roller of the guide hole drill bit rolling under the action of drilling pressure to generate an impact load, so that the roller teeth have an impact, extrusion and shearing effect on the rock, and crush the rock. In the present invention, strip recovery is achieved through the riser drill, so there is no need to use the blasting method, the stability of the surrounding rock is guaranteed, and the working conditions of personnel underground in the strip mining method can be effectively improved, the ventilation quality of the working face can be improved, and the strip mining efficiency can be effectively improved through mechanized transformation, and the labor intensity of workers can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of mining, in particular to a mechanized strip mining method. Background Art

[0002] Strip mining refers to a mining method that divides the mining block of the ore body into strips along a certain direction, and the strips are alternately arranged with the retained strips to support the load of the overlying rock strata to control the movement of the surrounding rock. The area should not be less than the total area of ​​the mining block, so as to keep the surface movement and deformation within the allowable range. At present, the drilling and blasting method is widely used in non-coal mines for strip mining and recovery operations.

[0003] The existing drilling and blasting method for strip mining of ore bodies has the following main shortcomings: 1. The working face is a dead-end tunnel, ventilation is difficult, and the air quality of the working face is poor; 2. The working conditions are poor and the labor intensity of workers is high; 3. Compared with the ordinary open-field method, the production efficiency is low.

[0004] In addition, because the strip mining adopts the drilling and blasting technology, the blasting vibration has a certain impact on the stability of the surrounding rock, increasing the cost of tunnel support.

[0005] To this end, the present invention provides a mechanized strip mining method. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a mechanized strip mining method to solve the problems raised in the above-mentioned background technology. The present invention realizes strip mining through a shaft drilling rig, thereby eliminating the need to use blasting method, ensuring the stability of the surrounding rock, and can effectively improve the working conditions of personnel underground in strip mining of ore, improve the ventilation quality of the working face, and through mechanized transformation, effectively improve the efficiency of strip mining, reduce the labor intensity of workers, and can be applied to the mining of inclined and extremely inclined ore bodies, expand the scope of application of strip mining method, multiple strips can be mined at the same time, improve work efficiency, and intake air through the middle section transport tunnel. Local fans are arranged on the working face to assist ventilation, which can ensure ventilation effect and improve the air quality of the working face.

[0007] In order to achieve the above object, the present invention is realized by the following technical scheme: a mechanized strip mining method, in which a cutting uphill is arranged in the middle of the ore block, and the strip is mined in two steps, and cementation filling is performed after the first step of mining, and the second step of mining is performed after the filling body reaches a certain strength, including the following steps:

[0008] S1. A raise drilling rig is set up in the middle level tunnel of the ore block, a pilot hole drill bit is installed on the raise drilling rig, and a pilot hole is drilled in the lower middle level tunnel through the pilot hole drill bit;

[0009] S2, insert the pilot hole drill bit into the horizontal tunnel, remove the pilot hole drill bit, and assemble the expansion drill bit on the skylight drilling rig;

[0010] S3, the reaming drill bit reams the hole from bottom to top to the upper horizontal tunnel, and then lowers the reaming drill bit to the lower middle horizontal tunnel of the ore block;

[0011] S4, rotating the auxiliary heads on both sides of the reaming drill bit to adjust the size of the reaming drill bit, and then performing secondary reaming through the reaming drill bit;

[0012] S5. The ore produced during the hole expansion process is transported and mined by a shovel loader or a scraper;

[0013] S5, after the hole is expanded and mined, the prying operation is carried out, and then the roof with poor stability is anchored;

[0014] S6. Air is introduced through the middle transport tunnel, and local fans are arranged on the working face to assist ventilation;

[0015] S7. After the first step of mining, a retaining wall is constructed at the junction of the strip and the segmented tunnel to close the empty area. After the second step of mining, the empty area is processed.

[0016] Furthermore, the guide hole connects the upper and lower middle level tunnels of the ore block.

[0017] Furthermore, the order of the first step of mining and the second step of mining is based on the stability of the ore layer and the surrounding rock, and the mining is carried out in the order of every other strip or every other strip, and multiple strips can be mined at the same time.

[0018] Furthermore, before mining, it is necessary to check the stability of the roof surrounding rock, and use anchor nets to support the roof in unstable areas. Ore mining can be carried out only after checking that the roof is stable.

[0019] Furthermore, when the middle section transport tunnel is intaken with air, fresh air flows through the internal ramp and segmented tunnels to the mining working faces on both sides. The dirty air after washing the mining area passes through the mining area and cuts up the mountain into the segmented tunnel of the upper level, and is discharged into the upper middle section flat tunnel through the internal ramp, and then discharged to the surface through the return air shaft.

[0020] Furthermore, after the first step of mining is completed, the slurry is filled into the goaf by a mobile filling pump, and after the second step of mining is completed, Ph1 3 The ore layer adopts waste rock cementation filling method to treat the empty area, Ph2 2 The mining seam adopts the method of closing the goaf to deal with the goaf.

[0021] Furthermore, the contact rate of the slurry filling and the waste rock cementation filling is at least 85%.

[0022] Furthermore, the reaming drill bit is rotatably connected to the auxiliary head, and the bottoms of the reaming drill bit and the auxiliary head are both arc-shaped structures.

[0023] Furthermore, a fixing structure is installed between the reaming drill bit and the auxiliary head, and the fixing structure includes a plurality of bolts. After the auxiliary head is rotated, the auxiliary head is fixed by the bolts.

[0024] Furthermore, a gap is provided between the auxiliary head and the reaming drill bit, through which the ore is crushed and guided.

[0025] Beneficial effects of the invention: The invention provides a mechanized strip mining method.

[0026] Strip mining can be achieved through shaft drilling, which eliminates the need for blasting and ensures the stability of the surrounding rock. It can also effectively improve the working conditions of underground personnel in strip mining and improve the ventilation quality of the working face. Through mechanized transformation, the efficiency of strip mining can be effectively improved, and the labor intensity of workers can be reduced. It can also be applied to the mining of inclined and extremely inclined ore bodies, expanding the scope of application of the strip mining method. Multiple strips can be mined at the same time to improve work efficiency. Air is introduced through the middle transport tunnel, and local fans are arranged on the working face to assist ventilation, which can ensure ventilation effect and improve the air quality of the working face. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Ph2 in a mechanized strip mining method of the present invention 2 Schematic diagram of the strip cementation filling method of the mineral layer;

[0028] Figure 2 A schematic cross-sectional view of a ore layer in a mechanized strip mining method of the present invention;

[0029] Figure 3 It is a schematic diagram of the structure of a raise boring machine in a mechanized strip mining method of the present invention;

[0030] Figure 4 It is a schematic diagram of the assembly structure of a drill rod and a reaming drill bit in a mechanized strip mining method of the present invention;

[0031] Figure 5 It is a schematic diagram of the assembled three-dimensional structure of a reaming drill bit and an auxiliary head in a mechanized strip mining method of the present invention;

[0032] Figure 6 It is a schematic diagram of the assembly cross-sectional structure of a reaming drill bit and an auxiliary head in a mechanized strip mining method of the present invention;

[0033] In the figure: 1. Segmented tunnel; 2. Intermediate pillars; 3. Waste rock cemented filling body; 4. Continuous ore pillars; 5. Filling retaining wall; 6. Skyhole drilling rig; 7. Drill rod; 8. Reaming drill bit; 9. Auxiliary head; 10. Rotating shaft; 11. Gap. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0035] See also Figures 1 to 6 The present invention provides a technical solution: a mechanized strip mining method, including arranging a cutting uphill in the middle of the ore block, mining the strip in two steps, cementing and filling after the first step of mining, and then mining the second step after the filling body reaches a certain strength, including the following steps:

[0036] S1. A raise drilling rig is set up in the middle level tunnel of the ore block, a pilot hole drill bit is installed on the raise drilling rig, and a pilot hole is drilled in the lower middle level tunnel through the pilot hole drill bit;

[0037] S2, insert the pilot hole drill bit into the horizontal tunnel, remove the pilot hole drill bit, and assemble the expansion drill bit on the skylight drilling rig;

[0038] S3, the reaming drill bit reams the hole from bottom to top to the upper horizontal tunnel, and then lowers the reaming drill bit to the lower middle horizontal tunnel of the ore block;

[0039] S4, rotating the auxiliary heads on both sides of the reaming drill bit to adjust the size of the reaming drill bit, and then performing secondary reaming through the reaming drill bit;

[0040] S5. The ore produced during the hole expansion process is transported and mined by a shovel loader or a scraper;

[0041] S5, after the hole is expanded and mined, the prying operation is carried out, and then the roof with poor stability is anchored;

[0042] S6. Air is introduced through the middle transport tunnel, and local fans are arranged on the working face to assist ventilation;

[0043] S7. After the first step of mining, a retaining wall is constructed at the junction of the strip and the segmented tunnel to close the empty area. After the second step of mining, the empty area is processed.

[0044] In this embodiment, the guide hole connects the upper and lower middle sections of the ore block. The order of the first step mining and the second step mining is based on the stability of the ore layer and the surrounding rock. The mining is carried out in the order of every other strip or every other strip. Multiple strips can be mined at the same time. Before mining, the stability of the roof surrounding rock needs to be checked. Anchor nets are used to support the roof in unstable places. After checking that the roof is stable, ore mining can be carried out.

[0045] When the middle transport tunnel is intaken with air, fresh air flows through the internal ramps and segmented tunnels to the mining faces on both sides. The dirty air after washing the mining area passes through the mining area and cuts up the mountain into the segmented tunnel on the upper level. It is discharged into the upper middle level tunnel through the internal ramps and then discharged to the surface through the return air shaft.

[0046] After the first step of mining is completed, the slurry is filled into the goaf by a mobile filling pump. After the second step of mining is completed, Ph1 3 The ore layer adopts waste rock cementation filling method to treat the empty area, Ph2 2 The ore layer adopts the method of sealing the goaf to treat the goaf, and the top connection rate of slurry filling and waste rock cementation filling is at least 85%.

[0047] Specifically, the cutting is arranged in the middle of the ore block, and the strips are mined in two steps. The 5m strip is mined first, and then cemented filling is carried out after mining. After the filling body reaches a certain strength, the 7m strip is mined. The first step of mining and the second step of mining strips are mined in the order of one or three strips according to the stability of the ore layer and the surrounding rock. Multiple strips can be mined at the same time. Before mining, the stability of the roof surrounding rock should be checked. The roof should be supported with anchor nets in unstable places. After checking that the roof is stable, ore mining can be carried out.

[0048] A raise drill 6 is set up in the middle level of the upper block, equipped with a Φ250mm pilot drill bit. According to the inclination of the ore layer and the layout of the ore block, a pilot hole is drilled to the lower middle level. The pilot hole connects the upper and lower middle level of the ore block, and then the pilot hole is drilled through the lower horizontal roadway by the pilot drill bit. The pilot drill bit is removed here, and the reaming drill bit 8 is connected. The size of the reaming drill bit 8 is adjusted to Φ1.4m, and then the reaming drill bit 8 is expanded from bottom to top to the upper horizontal roadway, and then the drill bit is lowered to the lower middle level of the ore block, and the size of the reaming drill bit 8 is adjusted to Φ2.0m, and then the reaming drill bit 8 is used for secondary expansion, and the expansion operation is carried out step by step according to the strip size. The broken rock mass in the expansion process is ore, and the ore is transported and mined by a ore digger or a shovel loader.

[0049] After the expansion and mining, the prying operation is carried out. If the roof is not stable, the roof is anchored after prying, and the middle section transport tunnel is used for air intake. The fresh air flows through the ramps and segmented tunnels in the vein to the mining working faces on both sides. The dirty air after washing the mining area goes up the mountain through the mining area cutting into the segmented tunnel on the upper level, and is discharged into the upper middle section of the flat tunnel through the ramps in the vein, and then discharged to the surface through the return air shaft. Local fans are arranged on the working face for auxiliary ventilation; after the first step of mining is completed, a filling retaining wall 5 is constructed at the connection between the strip and the segmented tunnel to close the empty area, and the slurry is filled into the mined area through a mobile filling pump; after the second step of mining is completed, Ph1 3 The ore layer adopts waste rock cementation filling method to treat the empty area, Ph2 2 The mining seam adopts the method of closing the goaf to deal with the goaf.

[0050] The filling rate is required to reach 85%

[0051] A rotating shaft 10 is installed between the reaming drill bit and the auxiliary head. The bottoms of the reaming drill bit and the auxiliary head are both arc-shaped structures. A fixing structure is installed between the reaming drill bit and the auxiliary head. The fixing structure includes multiple bolts. After the auxiliary head is rotated, the auxiliary head is fixed by the bolts. A gap 11 is provided between the auxiliary head and the reaming drill bit, and the ore is crushed and guided through the gap 11.

[0052] Specifically, the motor of the well drilling rig 6 drives the hydraulic motor, which drives the faucet and uses hydraulic power to transmit torque to the drilling tool system, driving the drill rod 7 to rotate, thereby driving the drill bit to rotate, so that the roller cutter on the pilot hole drill bit or the reaming drill bit 8, under the action of drilling pressure, rolls and slides slightly along the rock working surface at the bottom of the well. At the same time, the axial tension and pressure generated by the main engine oil cylinder also act on the pilot hole drill bit or the reaming drill bit 8 through the power head and the drill rod, so that the roller cutter of the pilot hole drill bit rolls under the action of drilling pressure, generates impact load, and causes the roller cutter teeth to impact, squeeze and shear the rock, thereby crushing the rock. The crushed rock cuttings are washed by the positively circulating well washing fluid when the pilot hole is drilled, and the rock cuttings are lifted to the outside of the borehole by the well washing fluid along the annular space between the drill rod and the hole wall. When the hole is expanded, the rock cuttings fall directly into the lower horizontal tunnel by their own weight, and are cleaned and transported out in time by rock loaders and transportation equipment. When drilling the pilot hole, the drill rod is continuously lengthened, and a small diameter hole of 200-300mm is formed from the upper level to the lower level that is drilled through. After that, the pilot hole drill bit is removed and the reaming drill bit 8 is installed. When reaming the hole, the drill rod is continuously removed until the drill rod is completely removed and the reaming drill bit 8 is pulled from the lower level to the upper level. For example, when drilling a Φ1.4m wellbore, it is only necessary to first drill a Φ250mm pilot hole until the pilot hole drills through the lower horizontal tunnel, remove the pilot hole drill bit here, connect the reaming drill bit 8, adjust the size of the reaming drill bit 8 to Φ1.4m, and then reaming the hole from bottom to top to the upper horizontal tunnel. If a Φ2.0m wellbore needs to be drilled, the Φ1.4m drill bit is lowered to the lower horizontal tunnel, and then the size of the reaming drill bit 8 is adjusted to Φ2.0m, and drilling continues from bottom to top until the drill bit is exposed. The strip width is generally 2 to 10m, and the strip height is generally 2 to 6m.

[0053] When the size of the reaming drill bit 8 needs to be adjusted, the auxiliary head 9 only needs to be rotated to expand the auxiliary head 9 outward, so that the size of the reaming drill bit 8 can be adjusted. After the adjustment is completed, the auxiliary head 9 can be fixed by bolts, so as to facilitate reaming.

[0054] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A mechanized strip mining method, characterized in that: The cutting process is arranged in the middle of the ore block, and the strip is mined in two steps. After the first step of mining, cementation filling is carried out. After the filling body reaches a certain strength, the second step of mining is carried out, including the following steps: S1. A raise drill is set up in the middle level tunnel of the upper part of the ore block, and a pilot drill is installed on the raise drill. A guide hole is drilled in the lower middle level tunnel through the pilot drill. The roller of the pilot drill rolls under the action of drilling pressure, generating an impact load, so that the roller teeth impact, squeeze and shear the rock to break the rock; the broken rock cuttings are washed by the positively circulating well washing fluid during the pilot hole drilling, and the rock cuttings are lifted to the outside of the borehole by the well washing fluid along the annular space between the drill rod and the hole wall; the drill rod is continuously lengthened during the pilot hole drilling, and a small diameter borehole is formed from the upper level to the drilled lower level; S2, drill the pilot hole drill bit through the lower horizontal tunnel, remove the pilot hole drill bit, and assemble the reaming drill bit on the skylight drilling rig; when reaming the hole, continuously remove the drill rod until the drill rod is completely removed and the reaming drill bit is pulled from the lower horizontal to the upper horizontal; S3, the reaming drill bit reams the hole from bottom to top to the upper horizontal tunnel, and then lowers the reaming drill bit to the lower middle horizontal tunnel of the ore block; S4, rotating the auxiliary heads on both sides of the reaming drill bit to adjust the size of the reaming drill bit, and then performing secondary reaming through the reaming drill bit; the reaming drill bit is rotatably connected to the auxiliary heads, and the bottoms of the reaming drill bit and the auxiliary heads are both arc-shaped structures; a fixing structure is installed between the reaming drill bit and the auxiliary heads, and the fixing structure includes a plurality of bolts, and the auxiliary heads are fixed by the bolts after the auxiliary heads are rotated; a gap is provided between the auxiliary heads and the reaming drill bit, and the ore is crushed and guided through the gap; S5. During hole expansion, the rock cuttings fall directly into the lower horizontal tunnel by their own weight; the ore produced during hole expansion is transported and mined by a shovel loader or scraper; S6, after the hole is expanded and mined, the prying operation is carried out, and then the roof with poor stability is anchored; S7. Air is introduced through the middle transport tunnel, and local fans are arranged on the working face to assist ventilation; S8. After the first step of mining, a retaining wall is constructed at the junction of the strip and the segmented tunnel to close the empty area. After the second step of mining, the empty area is processed.

2. A mechanized strip mining method according to claim 1, characterized in that: The guide hole is connected to the upper and lower middle level tunnels of the ore block.

3. A mechanized strip mining method according to claim 1, characterized in that: The order of the first step of mining and the second step of mining is based on the stability of the ore layer and the surrounding rock, and the mining is carried out in the order of every other strip or every other three strips. Multiple strips can be mined at the same time.

4. A mechanized strip mining method according to claim 1, characterized in that: Before the mining, it is necessary to check the stability of the roof surrounding rock. Anchor nets are used to support the roof in unstable areas. Ore mining can be carried out only after checking that the roof is stable.

5. A mechanized strip mining method according to claim 1, characterized in that: When the middle section transport tunnel is intaken with air, fresh air flows through the inner ramp and segmented tunnels to the mining working faces on both sides. The dirty air after washing the mining area flows through the mining area cutting up the mountain into the segmented tunnel on the upper level, and is discharged into the upper middle section flat tunnel through the inner ramp, and then discharged to the surface through the return air shaft.

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