A high-water filling method for old empty roadway in re-mining thick coal seams

Abstract

The present invention discloses a high-water filling method for old empty roadways in the roof of thick coal seams during re-mining, and relates to the technical field of filling thick coal seams in coal mines. The required filling device includes a slurry mixing tank, a slurry delivery pipe 1, a slurry delivery pipe 2, a mixing spiral, and a driving mechanism. The slurry mixing tank is fixed on the roof of the roadway, the mixing spiral is arranged in the middle of the slurry mixing tank, and the end of the mixing spiral is connected to the driving mechanism. The slurry delivery pipe 1 and the slurry delivery pipe 2 are both fixed on the slurry mixing tank, and a slurry outlet is provided on the slurry delivery pipe 1 and the slurry delivery pipe 2, and the slurry outlet faces the mixing spiral; a plurality of protrusions and recesses are respectively provided on both sides of the slurry mixing tank, with recesses between adjacent protrusions, a slurry outlet 1 is provided on the outermost vertical section of the protrusion, and a slurry outlet 2 is provided on the innermost vertical section of the recess. The present invention has high filling efficiency and adopts local filling, which saves the use of filling materials.

Description

Technical Field

[0001] The present invention relates to the technical field of thick coal seam filling in coal mines, and in particular to a high-water filling method for old empty tunnels in re-mining roofs of thick coal seams. Background Art

[0002] my country boasts abundant coal resources, but the occurrence of coal seams varies greatly. The diverse geological conditions and complex geological structures dictate the diverse mining methods employed. In recent years, mining areas and mines have continuously explored and innovated coal seam mining methods. However, there remains a significant gap between achieving safe, high-yield, and efficient mining.

[0003] Mining thick coal seams requires not only considering the impact of mining the lower strata on the upper strata, but also the impact and disturbance damage of existing, empty roadways in the upper strata. When mining the lower coal seam after the upper roadway has been excavated, the stress distribution in the overburden becomes even more complex. After the upper roadway is excavated, when the lower coal seam is mined, the upper coal seam, already disturbed and damaged, undergoes a redistribution of stress fields within it. This regenerative structure, a redistributed stress field, will redistribute again, causing structural instability in the coal seam and further damage to the coal mass, seriously impacting the safety of mining the lower strata.

[0004] The existing research on thick coal seam secondary mining and filling mainly includes:

[0005] Application No. 202111543371,0 discloses a goaf grouting control method for re-mining old goafs in extra-thick coal seams, comprising the following steps: Step 1: Determine the plane boundary of the re-mining area; Step 2: Calculate and determine the vertical boundary of the re-mining control; Step 3: Determine the layout method of ground directional drilling and underground drainage drilling, exploration layer, horizontal spacing, construction sequence and drilling structure requirements; Step 4: Determine the grouting material, pressure, end standard, grouting sequence, grouting and drilling coordination and other parameters under different working conditions; Step 5: Check and reinforce the grouting filling effect.

[0006] Application No. 201710687657.3 discloses a method for re-mining a coal pillar at a stop-mining line in an extra-thick coal seam, comprising the following steps:

[0007] (1) Simulate the location of the transport drift and track drift of the coal pillar re-mining working face; (2) Conduct comprehensive detection of the goaf of the original working face where the coal pillar of the stop mining line of the extra-thick coal seam is located to eliminate safety hazards; (3) Excavate a tunnel along the advancing direction of the coal pillar re-mining working face in the upper part of the extra-thick coal seam to fill the tunnel next to the tunnel; (4) Excavate the coal pillar re-mining working face return tunnel and auxiliary inclined tunnels to form a complete production system and arrange the coal pillar re-mining working face; (5) Drill holes from top to bottom in the tunnel floor to make filling pipelines; (6) Prepare filling paste and evenly inject it into the transport drift near the goaf of the original working face along the above-mentioned filling pipeline; (7) Carry out comprehensive mining on the coal pillar re-mining working face.

[0008] Although the above-mentioned existing technologies have filled the re-mining area, the filling effect needs to be further improved. Summary of the Invention

[0009] The purpose of the present invention is to provide a high-water filling method for old empty roadways in the roof of thick coal seams during re-mining, which has high filling efficiency and adopts local filling to save the use of filling materials.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] A high-water filling method for old empty roadway in re-mining thick coal seams comprises the following steps:

[0012] a. Prepare and install the required filling device

[0013] The filling device includes a slurry mixing tank, a slurry delivery pipe 1, a slurry delivery pipe 2, a mixing spiral and a driving mechanism. The slurry mixing tank is fixed on the top plate of the tunnel. The mixing spiral is arranged in the middle of the slurry mixing tank, and the end of the mixing spiral is connected to the driving mechanism. The slurry delivery pipe 1 and the slurry delivery pipe 2 are both fixed on the slurry mixing tank, and the two are distributed on both sides of the mixing spiral.

[0014] The slurry delivery pipe 1 is used to deliver one component of the high-water filling material required for filling, and the slurry delivery pipe 2 is used to deliver another component of the high-water filling material required for filling;

[0015] The slurry delivery pipe 1 and the slurry delivery pipe 2 are provided with slurry outlets, and the slurry outlets face the mixing spiral;

[0016] A plurality of raised portions and recessed portions are respectively provided on both sides of the slurry mixing tank, with the recessed portions being located between adjacent raised portions. The outermost vertical section of the raised portion is located on the side close to the slurry mixing tank, and the innermost vertical section of the recessed portion is located on the side close to the slurry delivery pipe 1 and the slurry delivery pipe 2. A slurry outlet 1 is provided on the outermost vertical section of the raised portion, and a slurry outlet 2 is provided on the innermost vertical section of the recessed portion. The horizontal distance between the outermost vertical section of each raised portion and the innermost vertical section of each recessed portion is 50 cm.

[0017] b. Fix the filling device described in step a as a whole in the center of the top of the tunnel, and ensure that the driving mechanism is connected to the mixing spiral; connect the slurry delivery pipe 1 to the container filled with high-water filling slurry A, and connect the slurry delivery pipe 2 to the container filled with high-water filling slurry B;

[0018] c. Turn on the mixing screw to rotate it, and deliver high-water filling slurry A and high-water filling slurry B through slurry delivery pipe 1 and slurry delivery pipe 2 respectively. The high-water filling slurry and high-water filling slurry B are discharged through the slurry outlets on their respective slurry delivery pipes, mixed evenly by the mixing screw, and discharged through slurry outlet 1 and slurry outlet 2 for filling;

[0019] d. When the slurry is conveyed under pressure, continue to convey it under pressure for 5 to 15 minutes and then stop conveying the slurry.

[0020] As a preferred solution of the present invention, the slurry delivery pipe 1 and the slurry delivery pipe 2 are both PVC plastic pipes, both have a diameter of 10 to 15 cm, and are fixed to the slurry mixing tank with rivets or adhesives.

[0021] As another preferred embodiment of the present invention, there are several slurry outlets, which are evenly distributed on the slurry delivery pipe 1 and the slurry delivery pipe 2.

[0022] More preferably, the distance between adjacent slurry outlets is 30 to 50 cm, and the diameter of each slurry outlet is 3 to 8 cm.

[0023] Furthermore, the length of the slurry mixing tank is 1.2 times the overlapping length of the lower working surface.

[0024] Further preferably, the driving mechanism is a pneumatic motor or an electric motor.

[0025] Furthermore, the high-water filling slurry A includes: gypsum, lime, clay, water, accelerating agent, and early strength agent; the high-water filling slurry B includes silicate cement, retarder, and water; the water-cement mass ratio is 11:1, and the two materials are mixed at a mass ratio of 1:1.5.

[0026] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0027] The present invention proposes a high-water filling method for old empty lanes in the roof of thick coal seams during re-mining, wherein the filling device is improved, slurry delivery pipe 1 and slurry delivery pipe 2 respectively deliver high-water filling slurry A and high-water filling slurry B, and are evenly mixed by a mixing spiral. More importantly, a plurality of protrusions and depressions are respectively provided on both sides of the slurry mixing tank, and the depressions are located between adjacent protrusions. The outermost vertical section of the protrusion is on the side close to the slurry mixing tank, and the innermost vertical section of the depression is on the side close to slurry delivery pipe 1 and slurry delivery pipe 2. The main purpose of such a design is that the slurry can flow to both sides and the middle of the lane at the outlet of the mixing slurry tank, respectively, to form local filling bodies on both sides and the middle of the lane, respectively, and the local filling bodies are used to support the roof, with less filling material and low cost.

[0028] The present invention adopts a specially designed filling device for filling, takes roof safety measures for the advancement of the working face in advance, and ensures the safety of the advancement of the re-mining working face.

[0029] The present invention adopts local filling, which reduces the use of filling slurry and reduces the cost of filling coal mining.

[0030] The filling device of the present invention is easy to manufacture and has low cost.

[0031] The method of the present invention is simple to operate and is worthy of popularization and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be further described below with reference to the accompanying drawings:

[0033] Figure 1 A top view of the filling device of the present invention;

[0034] Figure 2 It is a front view of the filling device of the present invention;

[0035] Figure 3 This is a schematic diagram of the filling effect of the method of the present invention;

[0036] In the picture:

[0037] 1. Tunnel, 2. Slurry conveying pipe 1, 3. Mixing spiral, 4. Slurry mixing tank, 5. Slurry conveying pipe 2, 6. Slurry outlet 1, 7. Slurry outlet 2, 8. Slurry outlet, 9. Driving mechanism, 10. Filling body. DETAILED DESCRIPTION

[0038] The present invention proposes a high-water filling method for old empty tunnels in the roof of thick coal seams during re-mining. In order to make the advantages and technical solutions of the present invention clearer and more specific, the present invention is further described below in conjunction with specific embodiments.

[0039] The "high-water-filled filler slurry A" and "high-water-filled filler slurry B" described in this invention have the following main components and proportions: Slurry A includes gypsum, lime, clay, water, an accelerating setting agent, and a strength accelerator; Slurry B includes Portland cement, a retarder, and water. The water-cement ratio is 11:1, and the two materials are mixed at a mass ratio of 1:1.5.

[0040] Combine Figure 1 、 Figure 2 As shown, the filling device required by the present invention includes a slurry mixing tank 4, a slurry conveying pipe 1 2, a slurry conveying pipe 2 5, a mixing spiral 3 and a driving mechanism 9. As a major improvement point of the present invention, the slurry mixing tank 4 is fixed on the top plate of the tunnel 1. The specific fixing method is to fix it on the top plate of the tunnel by bolts. The mixing spiral 3 is arranged in the middle of the slurry mixing tank 4. The length of the mixing spiral 3 is the same as the length of the slurry mixing tank 4. The specific structure of the mixing spiral 3 includes bearings arranged along the length direction of the slurry mixing tank. Both ends of the bearing are fixed at both ends of the slurry mixing tank, with a diameter of 10 cm. The end of the bearing passes through the slurry mixing tank and is connected to the driving mechanism 9. Spirally arranged blades are arranged on the periphery of the bearing. The bearing and the spirally arranged blades together constitute the mixing spiral 3.

[0041] The driving mechanism 9 includes a pneumatic motor or an electric motor, and the specific selection depends on the actual situation.

[0042] The driving mechanism drives the bearing to rotate, and the rotation of the bearing drives the spirally arranged blades to rotate, thereby evenly mixing the slurry A and slurry B discharged from the slurry conveying pipe 1 and the slurry conveying pipe 2, which is convenient for filling.

[0043] The slurry delivery pipe 1 and the slurry delivery pipe 2 are both fixed on the slurry mixing tank, and the two are distributed on both sides of the mixing spiral;

[0044] The slurry delivery pipe 1 is used to deliver one component of the high-water filling material required for filling, such as slurry A or slurry B, and the slurry delivery pipe 2 is used to deliver another component of the high-water filling material required for filling, such as slurry B or slurry A;

[0045] A slurry outlet 8 is provided on the slurry delivery pipe 1 and the slurry delivery pipe 2, and the slurry outlet faces the mixing spiral. The purpose of this design is that the slurry discharged from the slurry outlet is promptly mixed evenly by the mixing spiral before filling;

[0046] As another major improvement of the present invention, a plurality of raised portions and recessed portions are respectively provided on both sides of the slurry mixing tank, with recessed portions between adjacent raised portions, that is, the raised portions and the recessed portions are arranged at intervals, the outermost vertical section of the raised portion is on the side close to the slurry mixing tank, and the innermost vertical section of the recessed portion is on the side close to the slurry delivery pipe 1 2 and the slurry delivery pipe 2 5; a slurry outlet 1 6 is provided on the outermost vertical section of the raised portion, and a slurry outlet 2 7 is provided on the innermost vertical section of the recessed portion, and the horizontal distance between the outermost vertical section of each raised portion and the innermost vertical section of each recessed portion is 50 cm;

[0047] The above-mentioned slurry conveying pipe 1 and slurry conveying pipe 2 are both PVC plastic pipes, both of which have a diameter of 10 to 15 cm and are fixed to the slurry mixing tank with rivets or adhesives.

[0048] There are several slurry outlets mentioned above, which are evenly distributed on the slurry delivery pipe 1 and the slurry delivery pipe 2.

[0049] More preferably, the distance between adjacent slurry outlets is 30 to 50 cm, and the diameter of each slurry outlet is 3 to 8 cm.

[0050] Furthermore, the width of one slurry outlet is a cm (a=tunnel width-50 cm), the width of the second slurry outlet is 50 cm, and the length of the slurry mixing tank is 1.2 times the overlapping length of the lower working surface.

[0051] Combined with the above device, the high water filling method of old empty roadway in the roof of thick coal seam is described in detail. Figure 3 shown.

[0052] Step 1: According to the overlapping length between the working face and the old empty roadway above the working face, formulate and install the mixing spiral, slurry mixing tank, slurry delivery pipe 1 and slurry delivery pipe 2;

[0053] Step 2: Select the type of drive mechanism based on the actual situation of the mine. If there is a high-pressure air duct for easy use, a pneumatic motor is preferred;

[0054] Step 3: Assemble the slurry delivery pipe 1, the slurry delivery pipe 2, the mixing spiral and the slurry mixing tank together;

[0055] Step 4: Fix the whole structure at the center of the top of the tunnel and connect the drive mechanism;

[0056] Step 5: Connect the mine high-water filling slurry A and the high-water filling slurry B to the slurry delivery pipe 1 and the slurry delivery pipe 2 respectively;

[0057] Step 6: Start conveying the slurry and rotate the mixing screw 3;

[0058] Step 7: When there is pressure during slurry delivery, it proves that the goaf is almost filled. Pressurize and deliver for 10 minutes, then stop delivering the slurry.

[0059] The filling effect diagram after filling according to the above method is as follows Figure 3 As shown, the structure of the filling body 10 in the figure can ensure the safety of advancing the re-mining working face.

[0060] Parts not described in the present invention can be implemented by referring to the existing technology.

[0061] It should be noted that any equivalent manner or obvious variation made by those skilled in the art under the guidance of this specification should fall within the scope of protection of the present invention.

Claims

1. A high-water filling method for old empty roadway in re-mining thick coal seam roof, characterized in that: The following steps are included in sequence: a. Prepare and install the required filling device: The filling device includes a slurry mixing tank, a slurry delivery pipe 1, a slurry delivery pipe 2, a mixing spiral and a driving mechanism. The slurry mixing tank is fixed on the top plate of the tunnel. The mixing spiral is arranged in the middle of the slurry mixing tank, and the end of the mixing spiral is connected to the driving mechanism. The slurry delivery pipe 1 and the slurry delivery pipe 2 are both fixed on the slurry mixing tank, and the two are distributed on both sides of the mixing spiral. The slurry delivery pipe 1 is used to deliver one component of the high-water filling material required for filling, and the slurry delivery pipe 2 is used to deliver another component of the high-water filling material required for filling; The slurry delivery pipe 1 and the slurry delivery pipe 2 are provided with slurry outlets, and the slurry outlets face the mixing spiral; A plurality of raised portions and recessed portions are respectively provided on both sides of the slurry mixing tank, with the recessed portions being located between adjacent raised portions. The outermost vertical section of the raised portion is located on the side close to the slurry mixing tank, and the innermost vertical section of the recessed portion is located on the side close to the slurry delivery pipe 1 and the slurry delivery pipe 2. A slurry outlet 1 is provided on the outermost vertical section of the raised portion, and a slurry outlet 2 is provided on the innermost vertical section of the recessed portion. The horizontal distance between the outermost vertical section of each raised portion and the innermost vertical section of each recessed portion is 50 cm. b. Fix the filling device described in step a as a whole in the center of the top of the roadway and ensure that the drive mechanism is connected to the mixing screw; connect the slurry delivery pipe 1 to the container filled with high-water filling slurry A, and connect the slurry delivery pipe 2 to the container filled with high-water filling slurry B; c. Turn on the mixing screw to rotate it, and deliver high-water filling slurry A and high-water filling slurry B through the slurry delivery pipe 1 and the slurry delivery pipe 2 respectively. The high-water filling slurry A and the high-water filling slurry B are discharged through the slurry outlets on their respective slurry delivery pipes, mixed evenly by the mixing screw, and discharged through the slurry outlet 1 and the slurry outlet 2 for filling; d. When the slurry is conveyed under pressure, continue conveying under pressure for 5 to 15 minutes and then stop conveying the slurry; The distance between adjacent slurry outlets is 30 to 50 cm, and the diameter of each slurry outlet is 3 to 8 cm.

2. The method for high-water filling of old empty roadways in re-mining thick coal seams according to claim 1 is characterized by: The slurry conveying pipe 1 and the slurry conveying pipe 2 are both PVC plastic pipes, both have a diameter of 10 to 15 cm, and are fixed to the slurry mixing tank with rivets or adhesives.

3. The method for high-water filling of old empty roadways in re-mining thick coal seams according to claim 1 is characterized by: There are several slurry outlets, which are evenly distributed on the slurry delivery pipe 1 and the slurry delivery pipe 2.

4. The method for high-water filling of old empty roadways in re-mining thick coal seams according to claim 1 is characterized by: The length of the slurry mixing tank is 1.2 times the overlapping length of the lower working surface.

5. The method for high-water filling of old empty roadways in re-mining thick coal seams according to claim 1 is characterized by: The driving mechanism is a pneumatic motor or an electric motor.

6. The method for high-water filling of old empty roadways in re-mining thick coal seams according to claim 1 is characterized by: The high-water filling slurry A includes gypsum, lime, clay, water, accelerating agent and early strength agent, and the high-water filling slurry B includes silicate cement, retarder and water.

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