A quick mining method for thin coal seam working face in underground coal mine

Abstract

This invention provides a rapid mining method for thin coal seam working faces in underground coal mines, belonging to the technical field of underground coal mining. This method enables rapid lateral cutting and reciprocating motion of the coal face at the working face end. Compared with the current method of oblique cutting and reverse cutting at the end of fully mechanized thin coal seam working faces, it eliminates the reciprocating idle operation of some mining equipment and significantly shortens the auxiliary operation time during coal cutting, thus reducing the single-cycle operation time of the mining face and improving the mining efficiency of thin coal seam working faces. During rapid coal cutting with compact mining equipment, the low-profile scraper conveyor can be quickly moved along with the machine, and the hydraulic supports of the working face can be quickly moved, ensuring timely and effective support of the working face roof after coal seam cutting. The rapid mining method for thin coal seam working faces in underground coal mines proposed in this invention has good safety, technical, and economic benefits.

Description

Technical Field

[0001] This invention belongs to the technical field of underground coal mining, and specifically discloses a method for rapid mining of thin coal seams in underground coal mines. Background Technology

[0002] Due to the limitations of thin coal seams during mining, such as limited working space, limited equipment operation, restricted personnel activity area, and significant influence from geological conditions, mining equipment often cuts through a certain thickness of roof or floor strata to facilitate equipment layout and personnel operations. This results in high gangue content in the mined coal resources, high energy consumption per ton of coal, and slow mining speed, which is not conducive to the efficient mining of coal resources. Summary of the Invention

[0003] The purpose of this invention is to provide a rapid mining method for thin coal seams in underground coal mines, which reduces the auxiliary operation time for coal cutting at the working face, while reducing the amount of gangue mined during coal cutting and improving the mining efficiency of the working face.

[0004] The above-mentioned method for rapid mining of thin coal seams in underground coal mines includes the following steps:

[0005] S1 is a longwall mining face roadway system, including a transport roadway, a return air roadway, and a working face cut-out connecting the transport roadway and the return air roadway. It adopts a U-shaped ventilation method that enters from the transport roadway, passes through the working face cut-out, and returns from the return air roadway.

[0006] S2, the end hydraulic support, working face hydraulic support, low-profile scraper conveyor, and compact coal mining equipment are arranged in the working face cut. The low-profile scraper conveyor is arranged along the length of the working face. The head and tail of the low-profile scraper conveyor are located in the transport roadway and return air roadway, respectively. The compact coal mining equipment straddles the low-profile scraper conveyor. The transfer crushing equipment, belt conveyor, self-propelled tail section, and equipment train are arranged in the transport roadway.

[0007] S3 is a compact coal mining equipment that cuts along the side of the working face and is pulled back and forth by a low-profile scraper conveyor for cutting.

[0008] Step S1 includes:

[0009] t1, two parallel roadways are excavated along the roof of the thin coal seam, using the method of excavating along the roof and breaking through the bottom. Excavation is stopped after the roadways are excavated to the length required by the mining area plan, forming a transport roadway and a return air roadway;

[0010] t2, a working face cut is excavated along the direction perpendicular to the roadway axis. After the working face cut is connected with the transport roadway and the return air roadway, a longwall mining working face roadway system is formed.

[0011] In step S2, the low-profile scraper conveyor head and the lower transfer and crushing equipment transport coal by end unloading.

[0012] In step S2, the head of the low-profile scraper conveyor is connected to the lower transfer and crushing equipment through a telescopic drop support mechanism to ensure that the part of the low-profile scraper conveyor located in the transport chute and the part located in the working face cut are at the same height.

[0013] The lower part of the tail section of the low-profile scraper conveyor is equipped with a telescopic support mechanism to ensure that the part of the low-profile scraper conveyor located in the return air chute and the part located in the working face cut are at the same height.

[0014] Step S2 also includes completing the installation of the power supply system, liquid supply system, and control system required for the working face, in preparation for production at the working face.

[0015] Step S3 includes:

[0016] t1, Before coal cutting, both rollers of the compact coal mining equipment are located in the transport roadway. The front roller is close to the coal wall of the working face on the side of the transport roadway. The low scraper conveyor is pushed to the working face by a distance of 1 roller cutting depth through the hydraulic support of the working face to move the frame and keep the hydraulic support of the working face in a supported state.

[0017] t2, the compact coal mining equipment begins to cut coal. Under the pulling force provided by the low-profile scraper conveyor, the front drum of the compact coal mining equipment rotates into the coal wall of the working face, forming a coal pit at the edge of the working face corresponding to the head of the low-profile scraper conveyor. The depth of the coal pit is 1 cutting depth.

[0018] t3, the compact coal mining equipment continuously moves towards the tail side of the low scraper conveyor to cut coal. During the coal cutting process, the low scraper conveyor provides continuous and stable traction for the compact coal mining equipment. The compact coal mining equipment maintains a constant speed to cut coal. During the cutting process, the low scraper conveyor behind the compact coal mining equipment is pushed towards the working face through the hydraulic support of the working face and is supported by the moving support.

[0019] t4, when the front drum of the compact coal mining equipment cuts coal to the edge of the working face corresponding to the tail of the low scraper conveyor, it continues to run towards the tail of the low scraper conveyor until the rear drum completely enters the return air roadway and then stops running, completing one forward coal cutting cycle;

[0020] t5, the hydraulic support at the tail end of the low-profile scraper conveyor and the hydraulic support of the working face in the transition area push the low-profile scraper conveyor and move the support to keep the low-profile scraper conveyor on a straight line parallel to the coal wall of the working face;

[0021] t6, the hydraulic support of the working face is pushed as a whole by the low scraper conveyor, and the compact coal mining equipment is driven to advance to the working face by 1 cutting depth to move the support, so that the hydraulic support of the working face is kept in a supported state;

[0022] t7, the compact coal mining equipment runs in reverse under the traction force provided by the low-profile scraper conveyor. The rear drum in the forward coal cutting process becomes the front drum in the reverse coal cutting process. During the coal cutting process, the compact coal mining equipment closely follows the low-profile scraper conveyor and moves the frame. The compact coal mining equipment continues to run towards the head of the low-profile scraper conveyor to cut coal until the front and rear drums are completely in the transport roadway and then it stops running, completing one reverse coal cutting.

[0023] t8, the hydraulic support at the end of the head side of the low-profile scraper conveyor and the hydraulic support of the working face in the transition area push the low-profile scraper conveyor and move the support, keeping the low-profile scraper conveyor on a straight line parallel to the coal wall of the working face, completing one cycle.

[0024] In compact coal mining equipment, the front drum is used for breaking, dropping, and loading coal, while the rear drum is used for loading and breaking coal. The mining height can be adjusted by changing the diameter of the drums.

[0025] The cutting speed of the compact coal mining equipment is 10-20 m / min. When the compact coal mining equipment enters the transition area between the head and tail of the low-profile scraper conveyor, the cutting speed decreases. After the front drum enters the roadway, the speed decreases again. After the rear drum enters the roadway, the compact coal mining equipment comes to a complete stop.

[0026] Adjust the pulling force of the low-profile scraper conveyor according to the coal seam hardness, the degree of interbedded rock, and the cutting conditions of the roof and floor.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The rapid mining method for thin coal seams in underground coal mines proposed in this invention enables rapid lateral cutting and reciprocating motion of the coal face at the working face end. Compared with the current method of oblique cutting and reverse cutting at the end of fully mechanized thin coal seams, this method eliminates the reciprocating idle operation of some mining equipment and significantly shortens the auxiliary operation time during coal cutting, thus reducing the single cycle operation time of the mining face and improving the mining efficiency of thin coal seams. During rapid coal cutting with compact mining equipment, the method allows for rapid following and pushing of the low-profile scraper conveyor and rapid movement of the hydraulic supports at the working face, ensuring timely and effective support of the roof after coal seam cutting. The rapid mining method for thin coal seams in underground coal mines proposed in this invention has good safety, technical, and economic benefits. Attached Figure Description

[0029] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 A schematic diagram showing a compact coal mining equipment entering the transport roadway and starting cutting one cutting step.

[0031] Figure 2 A schematic diagram of a compact coal mining equipment cutting into the coal face on the head side;

[0032] Figure 3 A schematic diagram of a compact coal mining equipment cutting to the tail side of the working face;

[0033] Figure 4 A schematic diagram showing how compact coal mining equipment moves forward one step after entering the return air roadway to begin side-cutting and reverse coal cutting;

[0034] Figure 5 A schematic diagram of a compact coal mining equipment cutting the coal face into the tail side working face from the reverse side.

[0035] Figure 6 This is a schematic diagram of a compact coal mining equipment cutting in reverse into the face head side.

[0036] In the diagram: 1-Compact coal mining equipment; 2-Hydraulic support for the working face; 3-Low-profile scraper conveyor; 3.1-Head of low-profile scraper conveyor; 3.2-Tail of low-profile scraper conveyor; 4-Transfer and crushing equipment; 5-End hydraulic support; 6-Transport roadway; 7-Return air roadway; 8-Working face cutter; 100-Working face. Detailed Implementation

[0037] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] This embodiment provides a method for rapid mining of thin coal seams in underground coal mines. The equipment involved includes compact mining equipment 1, hydraulic support for the working face 2, low-profile scraper conveyor 3, transfer and crushing equipment 4, end hydraulic support 5, belt conveyor, self-moving tail section, equipment train, and centralized control system for the working face.

[0039] The low-profile scraper conveyor 3 is pushed forward by the hydraulic support, and the compact coal mining equipment 1 located in the transport roadway 6 is pushed forward by one step. The compact coal mining equipment 1 enters the coal face wall in the transport roadway 6 by lateral rotation and cutting. The low-profile scraper conveyor 3 provides continuous and constant traction force to run back and forth along the working face 100 to cut coal. During the coal cutting process, the mining height changes little. The front drum is mainly responsible for coal dropping and part of the coal loading work, while the rear drum is mainly responsible for coal loading and a small part of the cutting and dropping work.

[0040] The specific mining steps are as follows.

[0041] S1, Arrange the roadway system for the longwall mining face.

[0042] t1, two parallel roadways are excavated along the roof of the thin coal seam, using the method of excavating along the roof and breaking through the bottom. The drop between the roadway floor and the bottom of the thin coal seam is not less than 1000mm, the roadway width is not less than 5.5m, the height is not less than 2.3m, the centerline of the two parallel roadways is not less than 205.5m apart, the mining height of the working face is 1.2m, and the roadway excavation stops after reaching the length required by the mining area plan, forming the transport roadway 6 and the return air roadway 7;

[0043] t2, along the direction perpendicular to the roadway axis, excavate a large cross-section channel with a width of not less than 7m and a height of not less than 1.2m, namely the working face cut-out 8, which, after connecting with the parallel transport roadway 6 and return air roadway 7, forms the longwall mining working face roadway system;

[0044] t3, ventilation is provided to the working face 100, forming a U-shaped ventilation system that enters from the transport roadway 6, passes through the working face cut-out 8, and returns from the return air roadway 7.

[0045] S2, Layout of mining equipment at the working face

[0046] The end hydraulic support 5, the working face hydraulic support 2, the low-profile scraper conveyor 3, and the compact coal mining equipment 1 are arranged in the working face cut 8. The low-profile scraper conveyor 3 is arranged along the length of the working face 100, and its length is 9m longer than the actual mining length of the working face 100 (i.e., the distance between the coal wall of the working face in the transport roadway and the coal wall of the working face in the return air roadway). The head 3.1 and the tail 3.2 of the low-profile scraper conveyor are located in the transport roadway 6 and the return air roadway 7, respectively. The edge of the head 3.1 of the low-profile scraper conveyor is 500mm away from the coal wall of the transport roadway that is not in the working face, and the edge of the tail 3.2 of the scraper conveyor is 500mm away from the coal wall of the return air roadway that is not in the working face.

[0047] The compact coal mining equipment 1 straddles the low-profile scraper conveyor 3, which provides the operating power for the compact coal mining equipment 1 and enables it to move back and forth during the coal cutting process.

[0048] The re-loading crushing equipment 4, belt conveyor, self-propelled tail section, equipment train, etc. are arranged in the transport roadway 6;

[0049] The head of the low-profile scraper conveyor 3.1 and the lower transfer and crushing equipment 4 transport coal by end unloading. The two are connected by a telescopic drop support mechanism, which can meet the drop compensation requirements between the edge of the working face end and the bottom plate of the mining roadway, and ensure that the part of the low-profile scraper conveyor 3 located in the transport roadway 6 and the part located in the working face cut 8 are at the same height.

[0050] A telescopic support mechanism is provided at the lower part of the tail section 3.2 of the low-profile scraper conveyor to ensure that the part of the low-profile scraper conveyor 3 located in the return air chute 7 and the part located in the working face cut 8 are at the same height.

[0051] Complete the installation of the power supply system, liquid supply system, control system and other equipment required for working face 100, in order to prepare for production at working face 100.

[0052] S3, rapid recovery technology

[0053] t1, Before coal cutting, both rollers of the compact coal mining equipment 1 are located in the transport roadway 6. The front roller is close to the coal wall of the working face of the transport roadway. The low scraper conveyor 3 is pushed forward by the hydraulic support 2 of the working face to a distance of 800mm, which is a distance of 1 roller cutting depth. The frame is moved quickly so that the hydraulic support 2 of the working face can be kept in a timely support state.

[0054] t2, the compact coal mining equipment 1 starts cutting coal. Under the pulling force provided by the low scraper conveyor 3, the front drum of the compact coal mining equipment 1 rotates into the coal wall of the working face, and a coal pit is formed at the edge of the working face corresponding to the head 3.1 of the low scraper conveyor. The depth of the coal pit is 800mm.

[0055] t3, the compact coal mining equipment 1 continuously moves towards the tail 3.2 of the low scraper conveyor to cut coal. During the coal cutting process, the low scraper conveyor 3 provides a continuous and stable traction force for the compact coal mining equipment 1. The compact coal mining equipment 1 maintains a constant speed for cutting coal. During the cutting process, the low scraper conveyor 3 behind the compact coal mining equipment 1 is pushed towards the working face 100 in a timely manner through the hydraulic support 2 of the working face, and the support is moved in a timely manner for support.

[0056] t4, when the front drum of the compact coal mining equipment 1 cuts coal to the edge of the working face corresponding to the tail of the low scraper conveyor 3.2, it continues to run in the direction of the tail of the low scraper conveyor 3.2 until the rear drum completely enters the return air roadway 7 and then stops running, completing one forward coal cutting;

[0057] t5, the end hydraulic support 5 on the tail side 3.2 of the low-profile scraper conveyor and the working face hydraulic support 2 in the transition area should promptly push the low-profile scraper conveyor 3 and move the support in time to keep the low-profile scraper conveyor 3 on a straight line parallel to the coal wall of the working face;

[0058] t6, the hydraulic support 2 of the working face is pushed as a whole by the low scraper conveyor 3, and the compact coal mining equipment 1 is advanced to the working face 100 by 1 cutting depth, and the support is moved quickly so that the hydraulic support 2 of the working face can maintain a timely support state.

[0059] t7, the compact coal mining equipment 1 runs in reverse under the traction force provided by the low scraper conveyor 3. The rear drum in the forward coal cutting process becomes the front drum in the reverse coal cutting process. During the coal cutting process, the compact coal mining equipment 1 closely follows the low scraper conveyor 3 and moves the frame in time. The compact coal mining equipment 1 continues to run towards the head 3.1 of the low scraper conveyor to cut coal until the front and rear drums are completely entered into the transport roadway 6 and then stops running, completing one reverse coal cutting.

[0060] t8, the end hydraulic support 5 on the head 3.1 side of the low-profile scraper conveyor and the working face hydraulic support 2 in the transition area promptly push the low-profile scraper conveyor 3 and move the support in time to keep the low-profile scraper conveyor 3 on a straight line parallel to the coal wall of the working face, completing one cycle.

[0061] The compact coal mining equipment 1 features high power, high energy efficiency, short equipment length, and high reliability. During coal cutting operation, the cutting height of the front and rear drums remains basically unchanged. The front drum is mainly responsible for breaking, dropping, and loading coal, while the rear drum is mainly responsible for coal loading and some coal breaking operations.

[0062] The low-profile scraper conveyor 3 is equipped with a force monitoring system, which can adjust the force according to the coal seam hardness, the degree of interbedded rock, and the cutting conditions of the roof and floor.

[0063] The compact coal mining equipment 1 is equipped with a speed detection and control system, which can ensure that the compact coal mining equipment 1 has a relatively stable operating speed during the coal cutting process. The normal coal cutting operating speed is 10-20 m / min. When entering the transition area between the head and tail of the low-profile scraper conveyor, the operating speed begins to decrease. After the front roller enters the roadway, the speed decreases further. After the rear roller enters the roadway, the compact coal mining equipment 1 comes to a complete stop.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for rapid mining of thin coal seams in underground coal mines, characterized in that, Includes the following steps: S1 is a longwall mining face roadway system, including a transport roadway, a return air roadway, and a working face cut-out connecting the transport roadway and the return air roadway. It adopts a U-shaped ventilation method that enters from the transport roadway, passes through the working face cut-out, and returns from the return air roadway. S2, the end hydraulic support, working face hydraulic support, low-profile scraper conveyor, and compact coal mining equipment are arranged in the working face cut. The low-profile scraper conveyor is arranged along the length of the working face. The head and tail of the low-profile scraper conveyor are located in the transport roadway and return air roadway, respectively. The compact coal mining equipment straddles the low-profile scraper conveyor. The transfer crushing equipment, belt conveyor, self-propelled tail section, and equipment train are arranged in the transport roadway. S3, a compact coal mining equipment, involves side-cutting along the working face, with the cutting tool reciprocating and moving under the traction of a low-profile scraper conveyor. It includes: t1, Before coal cutting, both rollers of the compact coal mining equipment are located in the transport roadway. The front roller is close to the coal wall of the working face on the side of the transport roadway. The low scraper conveyor is pushed to the working face by a distance of 1 roller cutting depth through the hydraulic support of the working face to move the frame and keep the hydraulic support of the working face in a supported state. t2, the compact coal mining equipment begins to cut coal. Under the pulling force provided by the low-profile scraper conveyor, the front drum of the compact coal mining equipment rotates into the coal wall of the working face, forming a coal pit at the edge of the working face corresponding to the head of the low-profile scraper conveyor. The depth of the coal pit is 1 cutting depth. t3, the compact coal mining equipment continuously moves towards the tail side of the low scraper conveyor to cut coal. During the coal cutting process, the low scraper conveyor provides continuous and stable traction for the compact coal mining equipment. The compact coal mining equipment maintains a constant speed to cut coal. During the cutting process, the low scraper conveyor behind the compact coal mining equipment is pushed towards the working face through the hydraulic support of the working face and is supported by the moving support. t4, when the front drum of the compact coal mining equipment cuts coal to the edge of the working face corresponding to the tail of the low scraper conveyor, it continues to run towards the tail of the low scraper conveyor until the rear drum completely enters the return air roadway and then stops running, completing one forward coal cutting cycle; t5, the hydraulic support at the tail end of the low-profile scraper conveyor and the hydraulic support of the working face in the transition area push the low-profile scraper conveyor and move the support to keep the low-profile scraper conveyor on a straight line parallel to the coal wall of the working face; t6, the hydraulic support of the working face is pushed as a whole by the low scraper conveyor, and the compact coal mining equipment is driven to advance to the working face by 1 cutting depth to move the support, so that the hydraulic support of the working face is kept in a supported state; t7, the compact coal mining equipment runs in reverse under the traction force provided by the low-profile scraper conveyor. The rear drum in the forward coal cutting process becomes the front drum in the reverse coal cutting process. During the coal cutting process, the compact coal mining equipment closely follows the low-profile scraper conveyor and moves the frame. The compact coal mining equipment continues to run towards the head of the low-profile scraper conveyor to cut coal until the front and rear drums are completely in the transport roadway and then it stops running, completing one reverse coal cutting. t8, the hydraulic support at the end of the head side of the low-profile scraper conveyor and the hydraulic support of the working face in the transition area push the low-profile scraper conveyor and move the support, keeping the low-profile scraper conveyor on a straight line parallel to the coal wall of the working face, completing one cycle.

2. The method for rapid mining of thin coal seams in underground coal mines according to claim 1, characterized in that, Step S1 includes: t1, two parallel roadways are excavated along the roof of the thin coal seam, using the method of excavating along the roof and breaking through the bottom. Excavation is stopped after the roadways are excavated to the length required by the mining area plan, forming a transport roadway and a return air roadway; t2, a working face cut is excavated along the direction perpendicular to the roadway axis. After the working face cut is connected with the transport roadway and the return air roadway, a longwall mining working face roadway system is formed.

3. The method for rapid mining of thin coal seams in underground coal mines according to claim 1, characterized in that, In step S2, the low-profile scraper conveyor head and the lower transfer and crushing equipment transport coal by end unloading.

4. The method for rapid mining of thin coal seams in underground coal mines according to claim 3, characterized in that, In step S2, the head of the low-profile scraper conveyor is connected to the lower transfer and crushing equipment through a telescopic drop support mechanism to ensure that the part of the low-profile scraper conveyor located in the transport chute and the part located in the working face cut are at the same height. The lower part of the tail section of the low-profile scraper conveyor is equipped with a telescopic support mechanism to ensure that the part of the low-profile scraper conveyor located in the return air chute and the part located in the working face cut are at the same height.

5. The method for rapid mining of thin coal seams in underground coal mines according to claim 3 or 4, characterized in that, Step S2 also includes completing the installation of the power supply system, liquid supply system, and control system required for the working face, in preparation for production at the working face.

6. The method for rapid mining of thin coal seams in underground coal mines according to claim 1, characterized in that, In compact coal mining equipment, the front drum is used for breaking, dropping, and loading coal, while the rear drum is used for loading and breaking coal. The mining height can be adjusted by changing the diameter of the drums.

7. The method for rapid mining of thin coal seams in underground coal mines according to claim 1, characterized in that, The cutting speed of the compact coal mining equipment is 10~20m / min. When the compact coal mining equipment enters the transition area between the head and tail of the low scraper conveyor, the cutting speed decreases. After the front drum enters the roadway, the speed decreases again. After the rear drum enters the roadway, the compact coal mining equipment comes to a complete stop.

8. The method for rapid mining of thin coal seams in underground coal mines according to claim 1, characterized in that, Adjust the pulling force of the low-profile scraper conveyor according to the coal seam hardness, the degree of interbedded rock, and the cutting conditions of the roof and floor.

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