CN114673502A - A multi-mode disaster chain management method based on floor rock roadway - Google Patents

Abstract

The invention discloses a multi-mode disaster chain type treatment method based on a bottom plate rock roadway, wherein before and during tunneling of a coal roadway, pressure relief, permeability enhancement and grouting reinforcement are sequentially carried out on a target coal seam by using a cross-layer drilling hole and a grouting drilling hole, so that a reinforcement area and a pressure relief area are combined, and a reinforcement-relaxation structure formed in such a way can improve the gas extraction efficiency on one hand and can ensure the safe excavation progress and the later-stage stability maintenance of the coal roadway on the other hand; secondly, secondary extraction of abnormal occurrence gas in the coal seam can be realized by utilizing the directional drilling during stoping of the working face, and full-coverage extraction of the gas in the coal seam is realized by combining with a conventional gas extraction method of the coal seam; and finally, after the working face extraction of the current coal roadway is completed, the coal gangue produced during the tunneling of new coal roadways and bottom plate rock roadways of other continuous working faces can be filled into the currently abandoned bottom plate rock roadway, and multiple purposes of saving gangue, improving cost, protecting surface ecological environment, preventing surface subsidence and the like can be simultaneously realized.

Description

A multi-mode disaster chain management method based on floor rock roadway

technical field

The invention relates to a multi-mode disaster chain management method based on floor rock roadway, which is mainly suitable for practical projects such as high-gas and low-permeability coal seam gas full-time drainage and coal gangue efficient disposal.

Background technique

The highly intensive mechanical mining mode makes the coal mining gradually extend to the deep. In order to ensure the safe and smooth mining of coal seams, a series of coal seam pressure relief technologies and gas drainage methods are usually used to strengthen pressure relief and drainage of pre-mined coal seams, such as hydraulic fracturing, hydraulic punching, protective layer mining, bedding gas drainage, and piercing. Layer gas extraction, etc. Coal seams with protective layer mining conditions can preferentially use protective layer mining methods, while those without protective layer mining conditions mostly rely on floor rock roadways and through-layer drilling to control gas disasters. At the same time, a large amount of coal gangue produced in the mining process of different working faces is usually lifted from the mine to the ground for stacking, so as to ensure the operability of the underground space.

The existing floor rock roadway is usually used as the main place for gas disaster prevention and control before coal seam mining, mainly involving the implementation of through-bed drilling gas drainage and hydraulic pressure relief and permeability enhancement measures. The implementation of through-layer drilling can achieve the purpose of coal seam pressure relief and gas drainage to a certain extent, but there are often some application limitations in the actual production process: 1. The utilization efficiency of the existing floor rock roadway is low, and most floor rocks The setting of the roadway is mostly aimed at the gas disaster mode and the efficient gas drainage; 2. The hydraulic punching pressure relief method can effectively relieve the pressure of the coal seam structure, but the stability of the coal roadway structure in the later coal roadway excavation process is often adversely affected. 3. For some coal seams with complex geological structures, the gas pre-drainage of a single drilling hole before gas mining cannot well achieve the coal seam gas drainage standard, which greatly affects the continuous efficiency of mining face mining; 4. After the mining of the overlying coal seam is completed, the floor rock roadway is currently closed, and the large roadway space after sealing is easy to cause damage to the stratum structure and surface subsidence. At the same time, the coal gangue stacked on the ground will pollute the ground environment on the one hand, and at the same time, the inclusion of spontaneous combustion coal blocks will cause combustion accidents, which seriously threatens the safety of mine ground production. Therefore, it is urgent to propose a new method. By considering the different timeliness of the floor rock roadway, specific methods are adopted according to the different stages of the floor rock roadway, so as to ensure the support stability of the floor rock roadway. Improving the dual effect of gas extraction and effective disposal of coal gangue is one of the research directions of this industry.

SUMMARY OF THE INVENTION

In view of the problems existing in the above-mentioned prior art, the present invention provides a multi-mode disaster chain management method based on the floor rock roadway. Therefore, on the premise of ensuring the support stability of the floor rock roadway, the dual effects of improving gas drainage and effective disposal of coal gangue can be achieved.

In order to achieve the above purpose, the technical solution adopted in the present invention is: a multi-mode disaster chain management method based on floor rock roadway, the specific steps are:

A. First determine the starting position of the pre-excavated coal roadway in the coal seam and the design path of the excavation according to the coal seam conditions. After the completion of the coal roadway excavation, the floor rock roadway is constructed in the floor rock layer under the coal seam, and then from the top plate of the floor rock roadway to the floor rock roadway. Multiple through-layer holes are drilled from the same coal seam section, and the parts of the multiple through-layer holes in the same coal seam section are evenly distributed on both sides of the starting position of the pre-drilling coal roadway, and each through-layer hole passes through the target coal seam into the roof rock formation;

B. Arrange hydraulic punching equipment in the floor rock roadway, and inject high-pressure water into each through-layer drilling hole in turn through the hydraulic punching equipment, and the punching pressure is 10-15MPa. The coal body is punched out. The punching completion standard of each through-layer drilling hole is determined by the coal output of each through-layer drilling hole. A pressure relief area is formed in each of the coal seams, and then each through-layer borehole is sealed, and each through-layer borehole is connected to the gas drainage pipeline through pipelines for gas drainage, which is convenient for subsequent coal roadways in the coal seam. excavation inside;

C. According to the position of the coal roadway and the design path of the roadway determined in step A, start the coal roadway excavation. During the coal roadway excavation process, according to the direction of the floor rock roadway, every set distance is from the roof of the floor rock roadway to the current coal seam Drill a plurality of through-layer boreholes at the cross-section, and repeat the process of step B to complete the layout of the pressure relief areas on both sides of the coal roadway in the excavation; Several grouting holes are constructed in the current coal seam section, and each grouting hole is located around the coal roadway in the process of excavation. The grouting equipment is used to inject the grouting material into each grouting hole. After the grouting material is solidified, the A strengthening area is formed around the coal roadway of the current coal seam section, and the strengthening area is closer to the coal roadway than the pressure relief area; then multiple bolts are set from the coal roadway to the surrounding coal seam for support, so as to pass the set distance The combined effect of strengthening area and bolt support is formed, so as to ensure the overall stability of the coal roadway during the excavation period, until the entire coal roadway excavation work is completed;

D. After the excavation work of the coal roadway is completed, the mining of the coal seam working face starts. During the mining period, multiple directional drilling holes are constructed from the floor rock roadway to the coal body 30m in front of the coal seam working face, and each directional drilling hole passes through the coal seam and enters the roof rock layer. , and then each directional borehole is processed by the method of step B and then the secondary gas enhanced drainage is carried out, so as to ensure the safety and stability of the coal seam working face mining process;

E. After the mining of the current coal seam working face is completed, repeat steps A to D after the same coal seam and the current coal roadway are separated by a certain distance, and then determine the new coal roadway and floor rock roadway, and excavate the new coal roadway and floor rock roadway. The generated coal gangue is transported to the current floor rock roadway for wet sealing filling. At the same time, the currently formed pressure relief area can be used when the new coal roadway is excavated, so as to ensure the safety and stability of the coal roadway excavation and subsequent use, and improve the coal roadway excavation. efficiency.

Further, the coal output in the step B is obtained by multiplying the length of the drilled hole in the coal seam by the coal output per meter, wherein the coal output per meter is 1.5t/m～3t/m. Through this judgment standard, different perforation holes can have their own punching end standards, so as to effectively improve the construction efficiency under the premise of realizing the pressure relief effect.

Further, the formation range of the strengthening area is 15-20m from the coal roadway; the formation range of the pressure relief area is 120-150m from the coal roadway. Using this setting range can effectively reduce the construction quantity of various drilling holes and improve the construction efficiency under the premise of ensuring the respective roles of the strengthening area and the pressure relief area in the process of coal roadway excavation and later working face mining.

Further, the final hole positions of the through-layer drilling, grouting drilling and directional drilling all enter the roof rock layer by at least 1 m. In this way, the stability after drilling of each borehole can be ensured.

Further, on the cross section of the same coal seam, each through-layer borehole is distributed in a fan shape along the coal seam inclination, and the included angle between the adjacent through-layer boreholes on each side of the coal roadway is 30°; the diameter of each through-layer borehole is 80~ 100mm; the diameter of the grouting hole is 50-80mm, and the diameter of the directional drilling is 50-80mm.

Further, the construction form of the directional drilling adopts the combined construction of high-level drilling and layer-wise drilling. This method can better improve the gas extraction effect.

Further, the grouting material adopts cement mortar mixed with a rapid coagulant, the water-cement ratio is 1:3, and the grouting equipment adopts a pneumatic grouting pump for grouting, and the grouting time is controlled within 30-40 minutes. The use of this grouting material makes the reinforcement strength of the reinforced area better.

Compared with the prior art, the present invention considers the three engineering integration of gas comprehensive control, rapid excavation and stabilization of coal roadway, and on-site filling of coal gangue under different time effects of floor rock roadway, and comprehensively considers coal roadway excavation on the time scale. Continuity with gas extraction, improve the implementation efficiency of coal seam mining, gas control and gangue filling on the spatial scale, and maximize the gas disaster prevention and other In-situ disposal efficiency of coal gangue in the continuous working face. First of all, before and during the excavation of the coal roadway, the target coal seam is subjected to pressure relief and penetration enhancement and grouting reinforcement in turn by using through-bed drilling and grouting drilling, so as to form a combination of strengthening area and pressure relief area around the coal roadway. In this way, the strengthening area is closer to the coal roadway, and the pressure relief area is on both sides of the strengthening area. The "strengthening-relaxation" structure formed in this way can improve the gas extraction efficiency on the one hand, and ensure the safe mining progress and safety of the coal roadway on the other hand. Stability maintenance in the later stage; secondly, directional drilling can be used to realize the secondary extraction of abnormally occurring gas in the target coal seam during the mining of the working face, and combined with the conventional gas extraction method of the coal seam, the full coverage of coal seam gas extraction can be realized; finally, After completing the mining of the working face of the current coal roadway, the coal gangue produced during the excavation of the new coal roadway and the floor rock roadway in other continuous working faces can be filled into the currently abandoned floor rock roadway, which can simultaneously save the cost of gangue and increase the cost of gangue. It has multiple purposes such as protecting the surface ecological environment and preventing surface subsidence; and the newly formed pressure relief area can be partially used during the excavation of the new coal roadway, so as to reduce the construction process and improve the coal roadway under the premise of ensuring the safety and stability of the coal roadway excavation and subsequent use. excavation efficiency.

Description of drawings

Fig. 1 is the governance construction schematic diagram of a coal roadway and floor rock roadway in the present invention;

Fig. 2 is a schematic diagram of a cross-sectional view of bolt reinforcement in the coal roadway excavation process in Fig. 1;

Fig. 3 is the sectional schematic diagram of the spatial arrangement of directional drilling in Fig. 1;

FIG. 4 is a schematic diagram of the governance construction of a plurality of coal roadways and floor rock roadways of the present invention.

In the figure: 1-coal seam; 2-floor rock road; 3-roof rock layer; 4-grouting drilling; 5-through drilling; 6-coal roadway; 7-anchor; 8-directional drilling; Reinforced area; II - pressure relief area; III - in situ area.

Detailed ways

The present invention will be further described below.

As shown in Figure 1, the concrete steps of the present invention are:

A. First determine the starting position and the design path of the pre-drilling coal road 6 in the coal seam 1 according to the situation of the coal seam 1, and then construct the floor rock roadway 2 in the floor rock layer below the coal seam 1 before the coal roadway 6 is excavated, and then from the The roof of the floor rock roadway 2 is drilled with a plurality of through-layer holes 5 to the same coal seam section, and the parts of the plurality of through-layer holes 5 in the same coal seam section are evenly distributed on both sides of the starting position of the pre-drilled coal roadway 6, Each through-layer drilling hole 5 passes through the target coal seam 1 and enters the roof rock layer 3; on the same coal seam section, each through-layer drilling hole 5 is fan-shaped along the coal seam inclination, and each through-layer drilling hole 5 on each side of the coal road 6 The included angle between adjacent ones is 30°; the diameter of each through-layer drilling hole 5 is 80-100mm;

B. Arrange hydraulic punching equipment in the floor rock roadway 2, and inject high-pressure water into each layer-penetrating hole 5 in turn through the hydraulic punching equipment, and the punching pressure is 10-15MPa. The coal mass around the hole 5 is punched out, and the punching completion standard of each through-layer drilling hole 5 is determined by the coal output of each through-layer drilling hole 5, wherein the coal output is based on the amount of the through-layer drilling hole 5 in the coal seam 1. The length is multiplied by the coal output per meter, and the coal output per meter is 1.5t/m～3t/m. Through this criterion, different perforating holes 5 can have their own punching end standards, so that the construction efficiency can be effectively improved under the premise of realizing pressure relief; after the hydraulic punching of each perforating hole 5 is completed, A pressure relief area II is formed in the coal seams 1 on both sides of the pre-drilled coal roadway 6, and then each through-layer borehole 5 is sealed, and each through-layer borehole 5 is connected to the gas extraction pipeline through pipelines. Carry out gas extraction to facilitate the excavation of the subsequent coal roadway 6 in the coal seam 1;

C, according to the coal roadway 6 positions determined by step A and the design path of excavation, start to carry out the coal roadway 6 excavation, in the coal roadway 6 excavation process, according to the direction of the floor rock roadway 2, every set distance from the top plate of the floor rock roadway 2 Drill a plurality of through-layer drill holes 5 to the current coal seam section, and repeat the process of step B to complete the layout of pressure relief areas II on both sides of the coal roadway 6 during the excavation; After the hole 5, a plurality of grouting holes 4 are constructed from the floor rock roadway 2 to the current coal seam section. The diameter of the grouting holes 4 is 50-80 mm, and each grouting hole 4 is located in the coal roadway 6 during the excavation. Around the grouting equipment, the grouting material is injected into each grouting hole 4. After the grouting material is solidified, a strengthening area I is formed around the coal road 6 of the current coal seam section, and the strengthening area I is relative to the pressure relief. The area II is closer to the coal road 6; as shown in Figure 2, a plurality of bolts 7 are set up from the coal road 6 to the surrounding coal seam 1 for support, thereby forming strengthened areas I and bolts 7 at every set distance The combined effect of support ensures the overall stability of the coal roadway 6 during the excavation period until the entire coal roadway 6 excavation work is completed; the formation range of the strengthening area I is 15-20m from the coal roadway; the formation range of the pressure relief area II is The coal lane is 120-150m. Using this setting range can effectively reduce the number of drilling holes and improve the construction efficiency under the premise of strengthening the respective roles of area I and pressure relief area II during the excavation of coal road 6 and the later working face mining process;

D. After completing the excavation work of the coal seam 6, start the mining of the coal seam working face. As shown in Figure 3, during the mining period, several directional drilling holes 8 are constructed from the floor rock roadway 2 to the coal body 30m in front of the coal seam working face. Directional drilling The diameter of the hole 8 is 50-80 mm, and the construction form of the directional drilling 8 adopts the combined construction of high-level drilling and layer-wise drilling. This method can better improve the effect of gas drainage; each directional drilled hole 8 passes through the coal seam 1 and enters the roof rock layer 3, and then each directional drilled hole 8 is processed by the method of step B for secondary gas enhanced drainage, Thus, the safety and stability of the coal seam working face recovery process is ensured; the final hole positions of the through-layer drilling holes 5, grouting holes 4 and directional drilling holes 8 all enter the roof rock layer by at least 1 m. In this way, the stability after drilling of each borehole can be ensured.

E. After the mining of the current coal seam working face is completed, repeat steps A to D after a certain distance between the same coal seam and the current coal roadway, as shown in Figure 4, and then determine the new coal roadway 6 and the floor rock roadway 2, and put the new The coal gangue generated during the excavation of the coal road 6 and the floor rock road 2 is transported to the current floor rock road 2 for wet sealing filling. At the same time, the new coal road 6 can use the currently formed pressure relief area II when the new coal road 6 is excavated, so as to ensure the coal roadway. 6. Under the premise of safe and stable driving and subsequent use, improve the driving efficiency of coal road 6. The process of wet sealing filling is as follows: use high-water materials mixed with coal gangue to fill the floor rock road 2, and set up buried pipes to perform negative pressure extraction of the air in the filling area; the injection pressure of high-water materials is 3-5MPa, The injection volume is the volume of floor rock roadway 2 minus the filling volume of coal gangue, and the extraction pressure of air negative pressure is 700-900kPa.

As an improvement of the present invention, the grouting material adopts cement mortar mixed with a rapid coagulant, the water-cement ratio is 1:3, and the grouting equipment adopts a pneumatic grouting pump for grouting, and the grouting time is controlled at 30 to 40 minutes. The use of this grouting material makes the reinforcement strength of the reinforcement region I better.

The above is only the preferred embodiment of the present invention, it should be pointed out that: for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can also be made, and these improvements and modifications are also It should be regarded as the protection scope of the present invention.

Claims (7)

1. a multi-mode disaster chain management method based on floor rock roadway, is characterized in that, concrete steps are: A. First determine the starting position of the pre-excavated coal roadway in the coal seam and the design path of the excavation according to the coal seam conditions. After the completion of the coal roadway excavation, the floor rock roadway is constructed in the floor rock layer under the coal seam, and then from the top plate of the floor rock roadway to the floor rock roadway. Multiple through-layer holes are drilled from the same coal seam section, and the parts of the multiple through-layer holes in the same coal seam section are evenly distributed on both sides of the starting position of the pre-drilling coal roadway, and each through-layer hole passes through the target coal seam into the roof rock formation; B. Arrange hydraulic punching equipment in the floor rock roadway, and inject high-pressure water into each through-layer drilling hole in turn through the hydraulic punching equipment, and the punching pressure is 10-15MPa. The coal body is punched out. The punching completion standard of each through-layer drilling hole is determined by the coal output of each through-layer drilling hole. A pressure relief area is formed in each of the coal seams, and then each through-layer borehole is sealed, and each through-layer borehole is connected to the gas drainage pipeline through pipelines for gas drainage, which is convenient for subsequent coal roadways in the coal seam. excavation inside; C. According to the position of the coal roadway and the design path of the roadway determined in step A, start the coal roadway excavation. During the coal roadway excavation process, according to the direction of the floor rock roadway, every set distance is from the roof of the floor rock roadway to the current coal seam Drill a plurality of through-layer boreholes at the cross-section, and repeat the process of step B to complete the layout of the pressure relief areas on both sides of the coal roadway in the excavation; Several grouting holes are constructed in the current coal seam section, and each grouting hole is located around the coal roadway in the process of excavation. The grouting equipment is used to inject the grouting material into each grouting hole. After the grouting material is solidified, the A strengthening area is formed around the coal roadway of the current coal seam section, and the strengthening area is closer to the coal roadway than the pressure relief area; then multiple bolts are set from the coal roadway to the surrounding coal seam for support, so as to pass the set distance The combined effect of strengthening area and bolt support is formed, so as to ensure the overall stability of the coal roadway during the excavation period, until the entire coal roadway excavation work is completed; D. After the excavation work of the coal roadway is completed, the mining of the coal seam working face starts. During the mining period, multiple directional drilling holes are constructed from the floor rock roadway to the coal body 30m in front of the coal seam working face, and each directional drilling hole passes through the coal seam and enters the roof rock layer. , and then each directional borehole is processed by the method of step B and then the secondary gas enhanced drainage is carried out, so as to ensure the safety and stability of the coal seam working face mining process; E. After the mining of the current coal seam working face is completed, repeat steps A to D after the same coal seam and the current coal roadway are separated by a certain distance, and then determine the new coal roadway and floor rock roadway, and excavate the new coal roadway and floor rock roadway. The generated coal gangue is transported to the current floor rock roadway for wet sealing filling. At the same time, the currently formed pressure relief area can be used when the new coal roadway is excavated, so as to ensure the safety and stability of the coal roadway excavation and subsequent use, and improve the coal roadway excavation. efficiency. 2. a kind of multi-mode disaster chain management method based on floor rock roadway according to claim 1 is characterized in that, the coal output in the described step B is multiplied by the length of the drilled hole in the coal seam by the length of each layer. The coal output per meter is obtained, of which the coal output per meter is 1.5t/m～3t/m. 3. A multi-mode disaster chain management method based on floor rock roadway according to claim 1, characterized in that, the formation range of the strengthening area is 15-20m away from the coal roadway; the formation range of the pressure relief area is It is 120-150m away from the coal lane. 4. a kind of multi-mode disaster chain management method based on floor rock roadway according to claim 1, it is characterized in that, the end hole position of described through-layer drilling, grouting drilling and directional drilling all enter the roof The rock formation is at least 1m. 5. A kind of multi-mode disaster chain management method based on floor rock roadway according to claim 1, it is characterized in that, on the same coal seam section, each drilled hole is distributed in fan shape along the coal seam inclination, and is located in each coal roadway. The angle between the adjacent through-layer drilling holes on the side is 30°; the diameter of each through-layer drilling hole is 80-100 mm; the diameter of the grouting drilling hole is 50-80 mm, and the diameter of the directional drilling hole is 50-80 mm . 6 . A multi-mode disaster chain management method based on floor rock roadway according to claim 1 , wherein the construction form of the directional drilling adopts the combined construction of high-level drilling and layer-wise drilling. 7 . 7. A kind of multi-mode disaster chain management method based on floor rock roadway according to claim 1, is characterized in that, described grouting material adopts cement mortar mixed with fast coagulant, and the water-cement ratio is 1:3 , and the grouting equipment adopts a pneumatic grouting pump for grouting, and the grouting time is controlled within 30 to 40 minutes.

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