Two-step upward approach stope safe and efficient ventilation structure and method

Abstract

The present invention discloses a safe and efficient ventilation structure and method for a two-step upward approach mining site, which comprises a capping channel arranged on the top plate of the one-step approach mining site, and a return air communication channel extending from the two-step approach mining site to the one-step approach mining site, wherein the capping channel extends along the length direction of the one-step approach mining site to the filling retaining wall and is connected with the observation hole of the filling retaining wall; one end of the return air communication channel is connected to the two-step approach mining site, and the other end is connected to the capping channel of the one-step approach mining site. The capping channel is used to raise the material discharge height of the later filling pipeline, thereby improving the filling and top connection effect of the one-step approach mining site; at the same time, by arranging a return air communication channel between the two-step approach mining site and the capping channel of the one-step approach mining site, the capping channel and the two-step approach mining site jointly form a mining site ventilation circuit of the two-step approach mining site, which not only realizes the secondary effective utilization of adjacent filling approach structures, but also shortens the safe ventilation time of the two-step approach mining site, thereby improving the recovery efficiency of the two-step approach mining site.

Description

Technical Field

[0001] The invention relates to the technical field of mining and filling, and in particular to a safe and efficient ventilation structure and method for a two-step upward approach stope. Background Art

[0002] At present, the two-step upward approach filling method generally adopts the pressure-in, extraction and mixed ventilation methods under the action of local fans and flexible flame-retardant ducts in series. In practical applications, due to the limitations of the approach mining section and the shape of mining equipment, the specifications of the ducts allowed to be installed in the tunnel (usually Φ400mm, cross-sectional area 0.13m2) are generally small, resulting in low ventilation efficiency and long ventilation time in the approach mining. In addition, due to the division of ore bodies and mining areas, the length of a single approach in some approaches is too long (some are as long as 50-60m), resulting in a series of problems such as long ventilation lines, large workload of duct erection, many air leakage points of canvas ducts, large air leakage, and short-circuit of wind flow in the mining area. These further reduce the ventilation efficiency and ventilation quality of the approach mining area, objectively prolong the safe ventilation time of the mining area, and cause many adverse effects on the production capacity and process connection of the mining area. What is more important is that the through-flow cannot be formed in the approach mining area, and there is no perfect mining area ventilation circuit. At the same time, through the secondary exposure of the filling body of some one-step approach mining areas during production, it was found that the average roof contact rate of the one-step filling approach was only 50%, and a large amount of filling gaps were left between the filling body surface and the approach roof, which would inevitably affect the safe mining of the two-step approach mining areas.

[0003] The invention patent with patent application number CN202210942748.8 discloses an upward horizontal stratified access filling mining ventilation structure in a mining area, which includes several mining access routes, stratified connecting roads and upper segmented return air tunnels for connecting the upper and lower walls of the ore body, and ventilation inclined shafts excavated along one side of the upper wall for connecting the stratified connecting roads and the upper segmented return air tunnels; several mining access routes are located in the layer where the stratified connecting roads are located, and the height of the mining access routes is lower than the height of the stratified connecting roads; an empty area is provided at the junction space between the mining access routes and the stratified connecting roads, and the airflow flows through the stratified connecting roads, mining access routes, empty areas, ventilation inclined shafts and upper segmented return air tunnels in sequence. This scheme realizes the ventilation circuit in the access route by excavating ventilation inclined shafts, but the excavation of ventilation inclined shafts is complicated, and each horizontally arranged access route at the same horizontal height in the panel area requires a horizontal connecting channel to be excavated to connect with the ventilation inclined shaft to form a ventilation circuit. The horizontal extension length is long, the construction is difficult, the support project is complex and the cost is high; and the large-scale height difference in space between the mining access route and the layered connecting road cannot accurately ensure that the mining access route is fully connected to the top.

[0004] In view of the above problems, it is urgent to develop a two-step upward approach mining field safe and efficient ventilation structure and method, which can improve the filling and top connection effect of the approach, and at the same time can form a mining field ventilation loop together with the adjacent approach mining field, thereby shortening the safe ventilation time of the approach and improving the mining efficiency of the approach. Summary of the invention

[0005] In order to overcome the shortcomings of the prior art, the present invention provides a two-step upward approach mining field safe and efficient ventilation structure and method, which can improve the filling and top connection effect of the approach, and at the same time can form a mining field ventilation loop together with the adjacent approach mining field, thereby shortening the safe ventilation time of the approach and improving the mining efficiency of the approach.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: to provide a safe and efficient ventilation structure for a two-step upward approach mining area, which includes a top pressure channel arranged on the top plate of the one-step approach mining area, and a return air communication channel extending from the two-step approach mining area to the one-step approach mining area, the top pressure channel extends along the length direction of the one-step approach mining area to the filling retaining wall, and is connected with the observation hole of the filling retaining wall; one end of the return air communication channel is connected to the two-step approach mining area, and the other end is connected to the top pressure channel of the one-step approach mining area.

[0007] Preferably, a communication pipe is installed on the observation hole, one end of the communication pipe is connected to the top pressure channel, and the other end extends to the outside of the first step access mining field.

[0008] Preferably, the return air communication channel is connected to the air outlet of the exhaust device at the heading face of the two-step approach mining field through a return air duct.

[0009] Preferably, the left and right side walls of the two-step approach mining area are respectively provided with a first return air communication channel and a second return air communication channel, and the first return air communication channel and the second return air communication channel are respectively connected to the top pressure channels of the left and right adjacent one-step approach mining areas.

[0010] Preferably, the air outlet of the exhaust device at the two-step approach mining face is connected to the first return air communication channel and the second return air communication channel through the return air duct.

[0011] The present invention also provides a two-step upward approach stope safe and efficient ventilation method, which comprises the following steps:

[0012] When mining the one-step approach stope, a top pressure channel extending along the length direction of the one-step approach stope is excavated on the top plate of the one-step approach stope;

[0013] After the first step of the access stope is mined, it is filled, and the top pressure channel extends to the filling retaining wall and is connected with the observation hole of the filling retaining wall;

[0014] When mining the two-step approach stope, a return air communication channel is constructed along the excavation direction of the two-step approach stope at a set distance toward the one-step approach stope to connect the top pressure channel in the one-step approach stope.

[0015] Preferably, a communication pipe is installed on the observation hole, one end of the communication pipe is connected to the top pressure channel, and the other end extends to the outside of the first step access mining field.

[0016] Preferably, the return air communication channel is blasted upward from the shoulder of the two-step approach mining area toward the adjacent one-step approach mining area to the top pressure channel and is connected with the top pressure channel.

[0017] Preferably, as the two-step approach mining face continues to advance forward, after each set distance of excavation, a new return air communication channel is again excavated near the face, and the previous return air communication channel is completely sealed.

[0018] Preferably, along the excavation direction of the two-step approach stope, return air communication passages are simultaneously constructed to the one-step approach stopes on both sides at a set interval to connect the top pressure passages in the one-step approach stopes on both sides.

[0019] The beneficial effects of the present invention are:

[0020] The two-step upward approach mining field safe and efficient ventilation structure and method described in the present invention, by reserving a top pressure channel in the one-step approach mining field to raise the material discharge height of the later filling pipeline, thereby improving the filling and top connection effect of the one-step approach mining field; at the same time, by setting a return air communication channel between the top pressure channel of the two-step approach mining field and the one-step approach mining field, the top pressure channel is used as a return air channel, and together with the two-step approach mining field, the mining field ventilation circuit of the two-step approach mining field is formed, thereby not only realizing the secondary effective utilization of adjacent filling approach structures, but also optimizing the operating environment in the two-step approach mining field, and greatly improving the ventilation efficiency of the two-step approach mining field, shortening the safe ventilation time of the two-step approach mining field. In summary, the recovery efficiency of the two-step approach mining field is improved as a whole.

[0021] The present invention arranges a first return air communication channel and a second return air communication channel on the left and right side walls of the two-step approach mining field respectively, and connects with the top pressure channels of the left and right adjacent one-step approach mining fields respectively through the first return air communication channel and the second return air communication channel, thereby providing two return air channels for the two-step approach mining field, so as to further improve the ventilation efficiency of the two-step approach mining field and shorten the safe ventilation time of the two-step approach mining field.

[0022] In order to ensure that the mining field ventilation circuit can lock and discharge the polluted air generated by the face blasting, the present invention, after each excavation of the two-step approach mining field face a set distance, a new return air communication channel is again excavated near the face, and the previous return air communication channel is completely sealed to avoid the problem that the previous return air communication channel and the top pressure channel of the one-step approach mining field form air turbulence away from the face, which is not conducive to the rapid discharge of polluted air from the face. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The present invention is a longitudinal cross-sectional view of mining in a stope using the two-step upward approach stope safe and efficient ventilation structure and method described in an embodiment of the present invention.

[0024] Figure 2 for Figure 1 Cross-sectional view of BB.

[0025] The markings of the components in the accompanying drawings are as follows:

[0026] 1. One-step approach to the mining area; 2. Two-step approach to the mining area; 3. Top pressure channel; 4. Unconnected gap; 5. Shallow blasthole; 6. Return air communication channel; 7. Return air duct; 8. Exhaust device; 9. Filling retaining wall; 10. Observation hole; 11. Approach filling body; 12. Filling filter pipe; 13. Filling hose. DETAILED DESCRIPTION

[0027] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0028] The present invention provides a two-step upward approach stope safe and efficient ventilation structure, such as Figure 1 and Figure 2 As shown, it includes a top pressure channel 3 arranged on the top plate of the one-step approach mining site 1, and a return air communication channel 6 extending from the two-step approach mining site 2 to the one-step approach mining site 1. The top pressure channel 3 extends along the length direction of the one-step approach mining site 1 to the filling retaining wall 9, and is connected with the observation hole 10 of the filling retaining wall 9; one end of the return air communication channel 6 is connected to the two-step approach mining site 2, and the other end is connected to the top pressure channel 3 of the one-step approach mining site 1.

[0029] By reserving a top pressure channel 3 in the one-step approach stope 1, the material discharge height of the later filling pipeline is raised, thereby improving the filling and top connection effect of the one-step approach stope 1; at the same time, by setting a return air connection channel 6 between the top pressure channel 3 of the two-step approach stope 2 and the one-step approach stope 1, the top pressure channel 3 is used as a return air channel, and together with the two-step approach stope 2, a stope ventilation circuit of the two-step approach stope 2 is formed, thereby not only realizing the secondary effective utilization of adjacent filling approach structures, but also optimizing the operating environment in the two-step approach stope 2, and greatly improving the ventilation efficiency of the two-step approach stope 2, and shortening the safe ventilation time of the two-step approach stope 2. In summary, the recovery efficiency of the two-step approach stope 2 is improved as a whole.

[0030] like Figure 2 As shown, the pressure-capping channel 3 extends along the length direction of the one-step access stope 1 to the filling retaining wall 9, and is connected to the observation hole 10 of the filling retaining wall 9, thereby forming a return air channel connected to the outside; specifically, a communication pipe is installed on the observation hole 10, one end of the communication pipe is connected to the pressure-capping channel 3, and the other end extends to the outside of the one-step access stope 1. The communication pipe is preferably a hard flame-retardant air duct with a length of 1m and an outer diameter of Φ300mm.

[0031] The return air communication channel 6 extends upward from the shoulder of the two-step approach stope 2 to the one-step approach stope 1 on both sides to the top pressure channel 3, connecting the two-step approach stope 2 with the top pressure channel 3, so that the top pressure channel 3 forms the return air channel of the two-step approach stope 2. Figure 1 As shown, the left and right side walls of the two-step approach mining field 2 are respectively provided with a first return air communication channel 6 and a second return air communication channel 6, and the first return air communication channel 6 and the second return air communication channel 6 are respectively connected to the top pressure channel 3 of the left and right adjacent one-step approach mining fields 1, thereby providing two return air channels for the two-step approach mining field 2, so as to further improve the ventilation efficiency of the two-step approach mining field 2 and shorten the safe ventilation time of the two-step approach mining field 2.

[0032] The return air communication channel 6 is arranged near the face of the two-step approach mining site 2; in the two-step approach mining site 2, an exhaust device 8 is arranged near the mining site face, and the air outlet of the exhaust device 8 is connected to the return air communication channel 6 through the return air duct 7; preferably, the air outlet of the exhaust device 8 is connected to the first return air communication channel 6 and the second return air communication channel 6 through the return air duct 7, such as Figure 1As shown, the return air duct 7 is a flexible flame-retardant three-way ventilator, one end of which is connected to the air outlet of the exhaust device 8, one end is connected to the first return air communication channel 6, and the last end is connected to the second return air communication channel 6. The exhaust device 8 absorbs the dirty air generated by the blasting of the face of the two-step approach stope 2 into the return air duct 7, and the first return air communication channel 6 and the second return air communication channel 6 are respectively discharged from the top pressure channel 3 in the left and right adjacent one-step approach stope 1.

[0033] Based on the two-step upward approach stope safe and efficient ventilation structure, the present invention also provides a two-step upward approach stope safe and efficient ventilation method, which comprises the following steps:

[0034] S1. When mining the one-step access stope 1, a top pressure channel 3 extending along the length direction of the one-step access stope 1 is excavated on the top plate of the one-step access stope 1;

[0035] S2, after the first step of mining, the entry stope 1 is filled, and the top pressure channel 3 extends to the filling retaining wall 9 and is connected with the observation hole 10 of the filling retaining wall 9;

[0036] S3. When mining the second-step approach stope 2, construct a return air communication channel 6 at a set distance along the excavation direction of the second-step approach stope 2 toward the first-step approach stope 1 to connect the top pressure channel 3 in the first-step approach stope 1.

[0037] Specifically, the capping channel 3 extends along the length direction of the one-step access stope 1 to the filling retaining wall 9, and is connected to the observation hole 10 of the filling retaining wall 9. A communication pipe is installed on the observation hole 10. One end of the communication pipe is connected to the capping channel 3, and the other end extends to the outside of the one-step access stope 1 to ensure that the capping channel 3 is connected to the outside. When filling the one-step access stope 1, the filling pipe is set up in the capping channel 3 to raise the material discharge height of the filling pipe to ensure the filling and top connection effect of the one-step access stope 1.

[0038] When mining the two-step approach mining area 2, as the face of the two-step approach mining area 2 continues to advance forward, the mining area ventilation circuit formed by the two-step approach mining area 2 and the top pressure channel 3 of the one-step approach mining area 1 must also advance inward; therefore, in order to ensure that the mining area ventilation circuit locks and discharges the polluted wind generated by the face blasting, after the face of the two-step approach mining area 2 is excavated a set distance, a new return air communication channel 6 is again excavated near the face, and the previous return air communication channel 6 is completely sealed to avoid the problem that the previous return air communication channel 6 and the top pressure channel 3 of the one-step approach mining area 1 form air turbulence away from the face, which is not conducive to the rapid discharge of polluted wind from the face.

[0039] Preferably, along the excavation direction of the two-step approach stope 2, return air communication channels 6 are simultaneously constructed to the adjacent one-step approach stopes 1 on both sides at a set distance, connecting the top pressure channels 3 in the adjacent one-step approach stopes 1 on both sides. Specifically, blasting is performed upward from the shoulder of the two-step approach stope 2 to the one-step approach stopes 1 on both sides to the top pressure channels 3, forming two return air communication channels 6 that are simultaneously connected to the top pressure channels 3 of the one-step approach stopes 1 on both sides; this is used to further improve the ventilation efficiency of the two-step approach stope 2 and shorten the safe ventilation time of the two-step approach stope 2.

[0040] The present invention takes a copper-nickel mine in Xinjiang as an example to further illustrate the safe and efficient ventilation method of the two-step upward approach stope. The ore rock of some sections of a copper-nickel mine in Xinjiang is broken, and the mine design adopts a two-step upward approach filling mining method for mining. The ore blocks are arranged along the direction of the ore body, with a length of 50 to 70m. The approach stope is arranged perpendicular to the direction of the ore body, and the approach specifications are 3.0 to 4.0m (width) × 3.0m (height), and the length is 20 to 60m. The approach stope uses a rock drilling trolley to construct shallow hole blastholes 5, and a diesel shovel loader is used to transport the mine out. The overall mining sequence in the ore block is from bottom to top, and the alternate mining form is adopted in the layered layer. The first step approach stope 1 is mined first, and then the full tailings are used for cementation filling. The design value of the 7-day compressive strength of the filling body is 1.0MPa, and then the two-step approach stope 2 is mined, and the full tailings are used for filling after completion.

[0041] During production, it was found that the ventilation time of some access roads was too long, the workload of erecting wind tubes was large, and the access wind tubes were frequently scratched and damaged by the shovel loaders, and the wind tubes had serious air leakage, and the overall ventilation efficiency of the mine was low. In addition, through the secondary exposure of some of the filling bodies of the first-step access stope 1, the mine found that the average roof connection rate of the first-step access stope 1 was only 50%, and there was a large amount of filling gaps between the filling body surface and the access roof, which would inevitably affect the safe mining of the second-step access stope 2.

[0042] To this end, the mine research decided to implement the "forced mining and forced exit" operation mode for the two-step approach stope 2 under the condition that the overall mining method remains unchanged, specifically, two mining cycles per day for a single approach, which puts higher requirements on the ventilation efficiency of the two-step approach stope 2. Therefore, when mining the two-step approach stope 2, the two-step upward approach stope safe and efficient ventilation method provided by the present invention is used to optimize the stope ventilation of the two-step approach stope 2, and at the same time improve the filling and top connection rate of the one-step approach stope 1. The specific transformation process is as follows:

[0043] like Figure 1 and Figure 2As shown, first, the one-step approach stope 1 is mined, and when the one-step approach stope 1 is mined, a 200mm×400mm square groove is simultaneously arranged on the roof to drill a blasthole, i.e., a top pressure channel 3. The top pressure channel 3 extends along the length direction of the one-step approach stope 1 to the filling retaining wall 9, and is connected with the observation hole 10 of the filling retaining wall 9; the top pressure channel 3 is used to raise the discharge height of the subsequent filling pipeline, thereby improving the filling and top connection rate of the one-step approach stope 1, and on the other hand, it serves as a return air channel for the adjacent two-step approach stope 2 in the later stage.

[0044] After the first-step access stope 1 is mined, a 1m long, Φ300mm outer diameter hard flame-retardant air duct is installed at the observation hole 10 of the filling retaining wall 9 of the first-step access stope 1 as a connection port outside the stope, and a Φ300mm inner diameter flexible flame-retardant air duct is used to extend and connect the connection port and the return air shaft to ensure that the top pressure channel 3 is connected to the outside. Then the first-step access stope 1 is filled.

[0045] Then the two-step approach mining site 2 was mined. In the initial stage of the mining of the two-step approach mining site 2, the traditional pressure-type local fan ventilation was continued. When it was advanced to 15m away from the opening, two shallow blastholes 5 were constructed from the shoulder of the two-step approach mining site 2 to the one-step approach mining sites 1 on both sides at a position of 10m. The hole depths were 1.2m and 1.8m, the spacing was 400mm, and the inclination angle was 50°. Then, a return air communication channel 6 was formed between the pressure top channel 3 in the adjacent one-step approach mining site 1 and the partially filled unconnected gap 4, and a 2m long, Φ300mm outer diameter hard flame-retardant air duct was installed in each of them. At the same time, an exhaust device 8 is installed 5m away from the face of the two-step approach stope 2, and a flexible flame-retardant three-way ventilation tube with an inner diameter of Φ300mm is used to connect the air outlet of the exhaust device 8 to the return air communication channel 6, so as to complete the construction of the first stope ventilation circuit in the two-step approach stope 2, and finally form a stope ventilation system with air intake in the two-step approach stope 2 and independent return air in the one-step top pressure channel 3. Preferably, during the recovery process of the two-step approach stope 2, wooden boards are used to temporarily block the return air wellhead, so that more airflow enters the two-step approach stope 2 and reduces the problem of airflow short circuit.

[0046] As the two-step approach stope 2 continues to advance forward, a new communication window is excavated again after each new excavation of 10m, and the previous return air communication channel 6 is completely sealed by the shotcrete method, so that the stope ventilation circuit of the two-step approach stope 2 is continuously extended forward in the advancement direction, and the spacing between the communication windows is about 10m. Preferably, the return air communication channel 6 and the surroundings of the observation hole 10 of the filling retaining wall 9 are tightly sealed by the shotcrete method.

[0047] After adopting the two-step upward approach mining field safe and efficient ventilation method provided by the present invention, the filling and roof connection rate of the mine's one-step approach mining field 1 is increased to more than 65%. At the same time, the safe ventilation time of the two-step approach mining field 2 is shortened from the previous 2 hours to less than 45 minutes. The mining efficiency of the two-step approach mining field 2 is greatly improved, and the ventilation energy consumption and material consumption per ton of ore are significantly reduced, providing safety and technical guarantee for the "strong mining and strong exit" operation requirements of the approach.

[0048] The above are only embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A two-step upward approach stope safe and efficient ventilation structure, It is characterized in that It includes a roof pressure channel arranged on the roof of the one-step approach stope, and a return air communication channel extending from the two-step approach stope to the one-step approach stope, the roof pressure channel extends along the length direction of the one-step approach stope to the filling retaining wall, and is connected with the observation hole of the filling retaining wall; one end of the return air communication channel is connected to the two-step approach stope, and the other end is connected to the roof pressure channel of the one-step approach stope; The left and right sides of the two-step access stope are respectively provided with a first return air communication channel and a second return air communication channel, and the first return air communication channel and the second return air communication channel are respectively connected to the top pressure channels of the left and right adjacent one-step access stopes; By setting a return air communication channel between the two-step approach stope and the top pressure channel of the one-step approach stope, the top pressure channel is used as a return air channel to form a stope ventilation circuit of the two-step approach stope together with the two-step approach stope.

2. The two-step upward approach stope safe and efficient ventilation structure according to claim 1, It is characterized in that A communication pipe is installed on the observation hole, one end of which is connected to the top pressure channel, and the other end extends to the outside of the first-step access mining field.

3. The two-step upward approach stope safe and efficient ventilation structure according to claim 1, It is characterized in that The return air communication channel is connected to the air outlet of the exhaust device at the heading face of the two-step approach mining field through the return air duct.

4. The two-step upward approach stope safe and efficient ventilation structure according to claim 1, It is characterized in that The air outlet of the exhaust device at the heading face of the second-step approach mining field is connected to the first return air communication channel and the second return air communication channel through the return air duct.

5. A two-step upward approach stope safe and efficient ventilation method, It is characterized in that The two-step upward approach stope safe and efficient ventilation structure as claimed in any one of claims 1 to 4 is used to carry out efficient ventilation treatment, comprising the following steps: When mining the one-step approach stope, a top pressure channel extending along the length direction of the one-step approach stope is excavated on the top plate of the one-step approach stope; After the first step of the access stope is mined, it is filled, and the top pressure channel extends to the filling retaining wall and is connected with the observation hole of the filling retaining wall; When mining the two-step approach stope, a return air communication channel is constructed along the excavation direction of the two-step approach stope at a set distance toward the one-step approach stope to connect the top pressure channel in the one-step approach stope.

6. The two-step upward approach stope safe and efficient ventilation method according to claim 5, It is characterized in that A communication pipe is installed on the observation hole, one end of which is connected to the top pressure channel, and the other end extends to the outside of the first-step access mining field.

7. The two-step upward approach stope safe and efficient ventilation method according to claim 5, It is characterized in that The return air communication channel is blasted upward from the shoulder of the two-step approach stope toward the adjacent one-step approach stope to the top pressure channel and is connected with the top pressure channel.

8. The two-step upward approach stope safe and efficient ventilation method according to claim 5, It is characterized in that As the second-step approach mining face continues to advance forward, after each set distance of excavation, a new return air communication channel is dug again near the face, and the previous return air communication channel is completely sealed.

9. The two-step upward approach stope safe and efficient ventilation method according to claim 5, It is characterized in that Along the excavation direction of the two-step approach stope, return air communication passages are constructed simultaneously to the one-step approach stopes on both sides at a set interval to connect the top pressure passages in the one-step approach stopes on both sides.

Images