A method for continuous mining and filling of a super-thick coal seam

Abstract

The application discloses a method for continuous mining and filling of extra-thick coal seams, and belongs to the technical field of mining of extra-thick coal seams. The method can solve the problems of conventional fully-mechanized mining and filling process of extra-thick coal seams, such as fast mining and slow filling, slow solidification, unbalanced mining and filling processes, poor process connection, limited mining height, great filling difficulty and great influence on the efficiency of filling mining. The method adopts a full-air-pressure continuous mining and filling process under the condition of extra-thick coal seams, can fully exert the characteristics of strong climbing ability, flexible movement, safety, intelligence, high yield and high efficiency of a complete set of continuous miner equipment, realizes layered mining and filling of extra-thick coal seams, and enables the two processes of mining and filling to be parallel operation without interference, so that the top-contact rate of the filling body can be fully ensured, and the method is a scientific, reasonable and green mining process.

Description

Technical Field

[0001] This invention belongs to the field of extra-thick coal seam mining technology, specifically relating to a method for continuous mining and filling of extra-thick coal seams. Background Technology

[0002] For extra-thick coal seams with a thickness of ≥6.0m, longwall mining faces challenges due to its fast extraction and slow filling processes, slow solidification, and unbalanced extraction and filling procedures. Top coal caving mining is also hampered by the difficulty of filling. Neither method adequately addresses these mining difficulties. Shortwall mining equipment, limited by existing domestic facilities, typically only allows for a single extraction height of 5-6m. There are also no effective solutions for mining and filling extra-thick coal seams ≥6.0m, resulting in complex mining processes and difficult filling. Summary of the Invention

[0003] This invention addresses the challenges of complex mining processes and difficult backfilling in the mining and backfilling of extra-thick coal seams (≥6.0m), providing a "three-under" (underground, underground, and under-pressure) full-ventilated shortwall mining method for extra-thick coal seams. This backfilling mining method can improve the recovery rate of extra-thick coal resources.

[0004] The present invention adopts the following technical solution:

[0005] A method for continuous mining and filling of extra-thick coal seams includes the following steps:

[0006] (1) Excavate return airway and transport roadway and cut-in in the area to be mined, and form a continuous mining and filling working face with full air pressure ventilation with the main transport roadway and return airway;

[0007] (2) Parallel and cut-off branch roadways;

[0008] (3) There are coal pillars between the branch roadways, and the width of the coal pillars is set at 2-3 times the width of the branch roadway;

[0009] (4) For branch roadway mining, after mining, seal walls are built at both ends of the transport roadway and return airway. The goaf filling process is arranged in a timely manner. After the strength of the filling body reaches the design requirements, the filling coal pillars can be mined in sequence.

[0010] Furthermore, the transport roadway is located in the lower part of the coal seam, the return air roadway is located along the roof, and the return air roadway is relatively higher than the transport roadway.

[0011] Furthermore, the length of the branch tunnel is no more than 200m and the width is no more than 10m.

[0012] Furthermore, the mining process employs a multi-round, top-down excavation method. First, in the first round of excavation, an opening is made in the haulage roadway of the section to be mined. The excavation proceeds perpendicular to the haulage roadway, at an uphill angle, until the coal seam roof is reached. Excavation continues along the coal seam roof until it connects with the return airway. The uphill angle does not exceed 10°. The excavator is then withdrawn to the haulage roadway entrance for the second round of excavation, proceeding at the coal seam dip angle until the return airway. The excavator is then withdrawn again to the haulage roadway opening for the third round of excavation, proceeding at a downhill angle until the coal seam floor is reached. Excavation continues along the coal seam floor until the return airway. Similarly, the downhill angle does not exceed 10°.

[0013] Furthermore, the filling process employs an intelligent pumping filling technique. The filling pipeline is laid through the return airway into the branch roadway, extending from the end of the return airway to the end of the transport roadway. The filling pipeline is suspended onto the roof of the branch roadway after the first round of excavation.

[0014] Furthermore, the filling pipeline includes special pipelines and ordinary pipelines arranged in alternating phases. The special pipeline has an opening in the middle for discharging the filling paste. A baffle is provided at the opening, and a telescopic cylinder is provided on the baffle. The openings are numbered sequentially from the end of the transport tunnel to the end of the return air tunnel, and are referred to as pipeline paste outlet one, pipeline paste outlet two, ..., pipeline paste outlet n. The ordinary pipeline is equipped with a pressure sensor and a video system. The output end of the pressure sensor is connected to a controller.

[0015] Furthermore, the intelligent pumping filling process includes the following steps:

[0016] After the pumping system starts, the pressure sensor transmits data to the controller. The controller determines the opening and closing of the baffle based on the received pressure value and displays the monitoring data on the display in real time. When the first outlet of the pipeline is in the open position and the others are in the closed position, the first stage of filling begins. The controller judges the transmitted pressure data and, based on the pre-set values, determines that the filling paste meets the design requirements. At this time, it sends a closing command to the telescopic cylinder connected to the baffle at the first outlet of the pipeline and an opening command to the telescopic cylinder at the second outlet of the pipeline. This completes the closing of the first outlet of the pipeline and the opening of the second outlet of the pipeline, and the second stage of filling begins. This process is repeated until the nth stage, completing the filling of the entire branch tunnel. At the same time, the video system displays the filling effect on the display. If the filling effect does not meet the design requirements, manual intervention is required. The controller is manually controlled to open and close specific outlets of the pipeline and supplement the filling material locally to enhance the filling effect.

[0017] The equipment such as filling pipelines in the branch tunnel are left in the branch tunnel. After the branch tunnel is filled, it should be sealed in a timely manner.

[0018] Repeat the above mining and backfilling steps until the mining and replacement of coal within the block is completed.

[0019] Finally, the cut-off holes, transport tunnels, and return air tunnels can be selectively filled.

[0020] In some embodiments, the branch roadway can be excavated simultaneously in two separate roadways. Preferred excavation and supporting equipment include continuous mining machines, bolt drilling rigs, and shuttle cars. The continuous mining machines and bolt drilling rigs operate in parallel and intersecting configurations within the branch roadway.

[0021] In some implementations, the branch tunnel is excavated using single-tunnel excavation, with preferred equipment including an integrated tunneling and anchoring machine and shuttle cars.

[0022] The beneficial effects of this invention are as follows:

[0023] This invention proposes a continuous mining and filling process under full-pressure conditions for extra-thick coal seams. It can give full play to the characteristics of continuous coal mining machine equipment, such as strong climbing ability, flexible movement, safety and intelligence, high production and efficiency, to realize layered filling mining of extra-thick coal seams. Moreover, the mining and filling processes do not interfere with each other and can be carried out in parallel, which can fully guarantee the roof contact rate of the filling body. It is a scientific, reasonable and green mining process.

[0024] The extra-thick coal seam full-air pressure shortwall backfilling mining method of the present invention can mine extra-thick coal seams under "three-under" pressure while ensuring safety, thereby improving the recovery rate of coal resources. Attached Figure Description

[0025] Figure 1 Schematic diagram of the layout of the continuous mining and charging working face;

[0026] Figure 2 A schematic diagram of the branch tunnel excavation process; wherein, (a) is a schematic diagram of the first round of branch tunnel excavation; (b) is a schematic diagram of the second round of branch tunnel excavation; and (c) is a schematic diagram of the third round of branch tunnel excavation.

[0027] Figure 3 Schematic diagram of the filling system in the branch tunnel;

[0028] Figure 4 Schematic diagram of intelligent filling control strategy;

[0029] Among them: 1-Branch roadway; 2-Coal pillar; 3-Return airway; 4-Main transport roadway; 5-Return airway; 6-Transport roadway; 7-Cut-out; 8-Filling pipeline; 9-Special pipeline; 10-Ordinary pipeline; 11-Pressure sensor; 12-Video device; 13-Telescopic cylinder; 14-Baffle. Detailed Implementation

[0030] The invention will be further described with reference to the accompanying drawings.

[0031] As shown in the figure, this invention proposes a shortwall mining method for extra-thick coal seams using a three-layer backfilling system with full ventilation. This backfilling mining method can improve the recovery rate of extra-thick coal resources.

[0032] The method for short-wall backfilling mining of extra-thick coal seams according to the present invention includes the following steps:

[0033] In the area to be mined, excavate return airway, transport roadway and cut-in, forming a continuous mining and filling working face with full air pressure ventilation with the main transport roadway and return airway.

[0034] The transport roadway is located in the middle and lower part of the coal seam, while the return air roadway is located along the roof, and the return air roadway is relatively higher than the transport roadway.

[0035] The branch tunnels are arranged parallel to each other and cut-off points, with a length generally not exceeding 200m and a width generally not exceeding 10m.

[0036] The width of the coal pillar can be determined according to the occurrence conditions and mining requirements. Generally, the width can be set at 2 to 3 times the width of the branch roadway.

[0037] After the branch roadway is mined, backfilling can be arranged. Once the strength of the backfill material reaches the design requirements, the backfill coal pillars can be mined in sequence.

[0038] For branch roadway mining, a multi-round excavation method can be adopted. First, in the first round of excavation, an opening is made in the haulage roadway section to be mined. The excavation proceeds perpendicular to the haulage roadway, at an uphill angle, until the coal seam roof is reached. Then, the excavation continues along the coal seam roof until it connects with the return airway. Considering the climbing ability of the mining system equipment, it is recommended that the uphill angle not exceed 10 degrees. The excavator is then withdrawn to the haulage roadway entrance for the second round of excavation, proceeding at the coal seam dip angle until the return airway is reached. The excavator is then withdrawn again to the haulage roadway opening for the third round of excavation, proceeding downhill at a downhill angle until the coal seam floor is reached. Then, the excavation continues along the coal seam floor until the return airway is reached. Similarly, it is recommended that the downhill angle not exceed 10 degrees.

[0039] After the branch roadway mining is completed, sealing walls are constructed at both ends of the transport roadway and return airway, and the goaf filling process is promptly arranged. The filling adopts an intelligent pumping filling process. The filling pipeline is laid through the return airway into the branch roadway, extending from the end of the return airway to the end of the transport roadway. The filling pipeline is suspended from the support anchors of the filling roadway. The portion of the intelligent filling pipeline within the branch roadway uses a special pipeline. This section has an opening in the middle of the pipe body for discharging the filling paste. A baffle is installed at the opening, and the opening and closing of the baffle is achieved by the extension and retraction of a telescopic cylinder. The paste outlets are sequentially numbered from the end of the transport roadway to the end of the return airway, referred to as outlet one, outlet two, ... outlet n. The special pipeline and ordinary pipeline are arranged alternately, and pressure sensors and a video system are installed on the ordinary pipeline. The pressure sensors are connected to a controller.

[0040] The intelligent filling control strategy is as follows: After the pumping system starts, the pressure sensor transmits data to the controller. The controller determines the opening and closing of the paste outlet baffle based on the received pressure value and displays the monitoring data on the display in real time. When paste outlet one is in the open position and the others are in the closed position, the first stage of filling begins. The controller judges the received pressure data and, based on pre-set values, determines that the filling paste meets the design requirements. At this point, it issues a closing command to paste outlet baffle cylinder one and an opening command to paste outlet cylinder two, completing the closing of paste outlet one and the opening of paste outlet two, thus entering the second stage of filling. This process continues until the nth stage, completing the filling of the entire branch tunnel. Simultaneously, the video system displays the filling effect on the display. If the filling effect does not meet the design requirements, manual intervention is possible. By manually controlling the controller, the opening and closing of specific paste outlets can be controlled to locally supplement the filling material and enhance the filling effect.

[0041] The equipment such as filling pipelines in the branch tunnel are left in the branch tunnel. After the branch tunnel is filled, it should be sealed in a timely manner.

[0042] Repeat the above mining and backfilling steps until the mining and replacement of coal within the block is completed.

[0043] Finally, the cut-off holes, transport tunnels, and return air tunnels can be selectively filled.

[0044] In some embodiments, the branch roadways can be excavated simultaneously in two separate roadways. Preferred excavation and supporting equipment include continuous mining machines, bolt drilling rigs, and shuttle cars. The continuous mining machines and bolt drilling rigs operate in parallel and intersecting positions within the branch roadways. The procedure is as follows: Within the entire mining area, a return airway 3 is first excavated using a complete set of continuous mining equipment. After completion, the unit is withdrawn, and a transport roadway 6 is excavated. After the transport roadway 6 is completed, two parallel branch roadways are excavated from the transport roadway 6 at two predetermined locations, heading towards the return airway. During tunneling, a parallel operation process is adopted for two branch roadways. That is, the continuous coal mining machine and the anchor drilling rig simultaneously carry out cutting and anchoring operations in the two branch roadways. After completing the tunneling cycle, the continuous coal mining machine and the anchor drilling rig switch positions. The continuous coal mining machine continues cutting in the branch roadway supported by the anchor drilling rig, and the anchor drilling rig continues anchoring support in the unsupported roof and sides of the roadway cut by the continuous coal mining machine. After completing this cycle, the two continue to switch positions and carry out the next cycle of tunneling until the branch roadway is connected to the return airway 3.

[0045] In some implementations, the branch roadway is excavated using single-roadway excavation, with preferred equipment including a roadheader-anchor machine and a shuttle car. The procedure is as follows: In the entire mining area, an upper return airway 3 is excavated first, followed by a lower transport roadway 6. Then, according to the predetermined position, the roadheader-anchor machine is used for opening excavation. The roadway cutting, temporary support, anchor bolt support, coal loading, and transfer are all completed by the roadway cutting, temporary support, anchor bolt support, coal loading, and transfer. The shuttle car receives the coal from the roadheader-anchor machine and transfers it to the belt conveyor at the working face.

Claims

1. A method for fully mechanized mining and simultaneous filling of a very thick coal seam, characterized in that: Includes the following steps: (1) Excavate return airway and transport roadway and cut-in in the area to be mined, and form a continuous mining and filling working face with full air pressure ventilation with the main transport roadway and return airway; (2) Arrange branch tunnels parallel to the cut-off point; (3) There are coal pillars between the branch roadways, and the width of the coal pillars is set at 2-3 times the width of the branch roadway; (4) For branch roadway mining, after mining, seal walls are built at both ends of the transport roadway and return airway. The goaf filling process is arranged in a timely manner. After the strength of the filling body reaches the design requirements, the filling coal pillars can be mined in sequence. The mining process employs a multi-round, top-down excavation method. First, in the first round of excavation, an opening is made in the haulage roadway of the section to be mined. The excavation proceeds perpendicular to the haulage roadway, at an uphill angle, until the coal seam roof is reached. Excavation continues along the coal seam roof until it connects with the return airway. The uphill angle does not exceed 10°. The excavator is then withdrawn to the haulage roadway entrance for the second round of excavation, proceeding at the coal seam dip angle until the return airway. The excavator is then withdrawn again to the haulage roadway opening for the third round of excavation, proceeding at a downhill angle until the coal seam floor is reached. Excavation continues along the coal seam floor until the return airway. Again, the downhill angle does not exceed 10°. The filling process adopts intelligent pumping filling technology. The filling pipeline is laid from the return airway to the branch roadway, extending from the end of the return airway to the end of the transport roadway. The filling pipeline is suspended on the roof of the branch roadway after the first round of excavation. The filling pipeline includes special pipelines and ordinary pipelines arranged in alternating phases. The special pipeline has an opening in the middle of the pipe body for discharging the filling paste. A baffle is installed at the opening, and a telescopic cylinder is installed on the baffle. The openings are numbered sequentially from the end of the transport tunnel to the end of the return air tunnel, and are called pipeline paste outlet one, pipeline paste outlet two, ... pipeline paste outlet n. The ordinary pipeline is equipped with a pressure sensor and a video system. The output end of the pressure sensor is connected to a controller. The intelligent pumping and filling process includes the following steps: After the pumping system is started, the pressure sensor transmits data to the controller. The controller determines the opening and closing of the baffle based on the received pressure value and displays the monitoring data on the display in real time. When the first outlet of the pipeline is in the open position and the others are in the closed position, the first stage of filling is performed. The controller judges the transmitted pressure data and determines that the filling paste meets the design requirements according to the preset value. At the same time, it sends a closing command to the telescopic cylinder connected to the baffle at the first outlet of the pipeline and an opening command to the telescopic cylinder at the second outlet of the pipeline. This completes the closing of the first outlet of the pipeline and the opening of the second outlet of the pipeline, and the second stage of filling begins. This process is repeated until the nth stage, completing the filling of the entire branch roadway. At the same time, the video system displays the filling effect on the display. If the filling effect does not meet the design requirements, manual intervention is performed. The controller is manually controlled to open and close specific outlets of the pipeline and supplement the filling material locally to enhance the filling effect.

2. The method for continuous mining and filling of extra-thick coal seams according to claim 1, characterized in that: The transport roadway is located in the lower part of the coal seam, and the return air roadway is located along the roof, with the return air roadway being higher than the transport roadway in relative position.

3. The method for continuous mining and filling of extra-thick coal seams according to claim 1, characterized in that: The length of the branch roadway shall not exceed 200m and the width shall not exceed 10m.

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