Room-pillar type goaf cemented filling device and method

Abstract

The room-pillar type goaf cemented filling device comprises a filling pipe and a bag, the filling pipe comprises a straight pipe section and a conical pipe section, the cross sectional area of the conical pipe section is gradually reduced in the direction from the straight pipe section to the conical pipe section, and a material passing hole is formed in the pipe wall of the straight pipe section; the bag surrounds the straight pipe section of the filling pipe by one circle, the two ends, in the axial direction of the filling pipe, of the bag extend to the edge of the first end and the edge of the second end respectively, and the bag is communicated with the material passing hole. The stability and safety of the goaf can be effectively improved, and surface collapse and rock stratum movement are prevented. The sealed space can effectively prevent slurry in the goaf from overflowing, and pollution to surrounding water resources and environment is reduced. The device is suitable for a closed room-pillar type goaf, can play a role in a large-space area where personnel or equipment is forbidden to enter, and solves the problem that a traditional filling method is difficult to apply.

Description

Technical Field

[0001] The present invention relates to the technical field of backfill mining, and particularly relates to a room-and-pillar goaf cemented filling device and method. Background Art

[0002] A goaf refers to the space formed during the underground mineral resource mining process due to the extraction of the ore body. The existence of the goaf will lead to uneven stress distribution in the underground rock strata, and further cause environmental problems such as surface subsidence, rock strata movement, and water resource pollution, seriously threatening the safe production of the mine and the surrounding ecological environment. Among them, the room-and-pillar goaf cemented filling treatment method is a new type of goaf treatment technology. Its main feature is to construct a room-and-pillar structure inside the goaf and fill the voids between the room and pillars with cemented filling materials to improve the stability and safety of the goaf. However, since the room-and-pillar goaf usually has been closed, the area is large and personnel or equipment are prohibited from entering. Traditional cemented filling methods are difficult to apply to the treatment of such goafs. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems in the related technologies to some extent.

[0004] To this end, an embodiment of the present invention provides a room-and-pillar goaf cemented filling device and method.

[0005] The room-and-pillar goaf cemented filling device according to the embodiment of the present invention includes a filling pipe and a bladder. The filling pipe includes a straight pipe section and a tapered pipe section. The straight pipe section includes a first end and a second end. The first end has an opening, and the second end is connected to the tapered pipe section. The cross-sectional area of the tapered pipe section gradually decreases along the direction from the straight pipe section to the tapered pipe section. A material passing hole is formed in the wall of the straight pipe section.

[0006] The bladder is disposed around the straight pipe section of the filling pipe for one week. The two ends of the bladder in the axial direction of the filling pipe respectively extend to the edges of the first end and the second end, and the bladder is communicated with the material passing hole.

[0007] In some embodiments, the number of the material passing holes is multiple, and the multiple material passing holes are arranged at intervals along the axial direction of the filling pipe.

[0008] In some embodiments, the room-and-pillar goaf cemented filling device according to the embodiment of the present invention includes a material conveying pipe and a stopper. One end of the material conveying pipe passes through the material passing hole and is communicated with the bladder. The other end of the material conveying pipe extends into the filling pipe. The stopper is disposed on the outer peripheral surface of the material conveying pipe and is located inside the filling pipe. The stopper is disposed around the material conveying pipe for one week and abuts against the inner wall of the filling pipe.

[0009] In some embodiments, a one-way valve is provided on the material conveying pipe, and the outlet of the one-way valve faces the bladder bag.

[0010] In some embodiments, the room-and-pillar goaf cemented filling device of the embodiments of the present invention further includes a base, the base is provided at the first end of the straight pipe section, the base is annular and coaxially arranged with the filling pipe, the outer diameter of the base is greater than the outer diameter of the bladder bag, and a grouting channel communicating with the straight pipe section is provided on the base.

[0011] In some embodiments, a pressure relief channel is provided on the base, the pressure relief channel has a first channel port and a second channel port, the first channel port communicates with the bladder bag, a pressure relief valve is provided at the second channel port, and when the grouting pressure in the bladder bag exceeds a preset value, the pressure relief valve opens.

[0012] The room-and-pillar goaf cemented filling method of the embodiments of the present invention, which is applied to the room-and-pillar goaf cemented filling device described in any of the above embodiments, includes the following steps:

[0013] S1. Divide the goaf into multiple filling areas, and determine the positions of the rib pillars and the middle pillars in each of the filling areas;

[0014] S2. Drill pipe holes between two adjacent rib pillars;

[0015] S3. Lower the filling pipe into the goaf through the pipe holes, insert the conical pipe section of the filling pipe on the floor of the goaf, and place the first end of the straight pipe section outside the goaf;

[0016] S4. Grout into the filling pipe through the opening at the first end of the straight pipe section, and grout into the bladder bag by using the filling pipe, so that the side of the bladder bag expands and abuts against two adjacent rib pillars;

[0017] S5. Wait for the slurry in the bladder bag to solidify, so that the rib pillars and the bladder bag enclose the filling area to form a sealed space;

[0018] S6. Drill filling holes between two adjacent middle pillars, and fill the sealed space of the filling area with slurry by using the filling holes.

[0019] In some embodiments, the bladder bag is a high-strength wear-resistant nylon cloth bag.

[0020] In some embodiments, in S5, the waiting time for the slurry to solidify is greater than or equal to seven days.

[0021] In some embodiments, the number of the filling holes is multiple and extends in the vertical direction.

[0022] The room-and-pillar gob-cementing filling device according to the embodiments of the present invention can effectively improve the stability and safety of the gob by constructing a room-and-pillar structure and adopting the method of bag filling, preventing surface subsidence and strata movement. The sealed space can effectively prevent the slurry in the gob from overflowing, reducing the pollution to the surrounding water resources and environment. This device is applicable to the already closed room-and-pillar gob and can play a role in areas with large space and where personnel or equipment are prohibited from entering, solving the problem that traditional filling methods are difficult to apply. Through the step-by-step construction method, the treatment process becomes more standardized and simple, which is beneficial to the improvement of construction efficiency and quality. This technology can reduce material waste during the treatment process, improve filling efficiency, thereby reducing the treatment cost and having good economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a flowchart of the room-and-pillar gob-cementing filling method according to the embodiments of the present invention.

[0024] Figure 2 is a schematic diagram before the room-and-pillar gob is filled according to the embodiments of the present invention.

[0025] Figure 3 is a layout schematic diagram of the room-and-pillar gob-cementing filling device according to the embodiments of the present invention.

[0026] Figure 4 is a schematic diagram after the room-and-pillar gob is filled according to the embodiments of the present invention.

[0027] Figure 5 is a structural schematic diagram of the room-and-pillar gob-cementing filling device according to the embodiments of the present invention.

[0028] Figure 6 is Figure 5 an enlarged schematic diagram of part A in

[0029] Figure 7 is a schematic diagram of the bag of the room-and-pillar gob-cementing filling device filled with slurry according to the embodiments of the present invention.

[0030] REFERENCE SIGNS:

[0031] 100, room-and-pillar gob-cementing filling device; 1, filling pipe; 101, straight pipe section; 1011, first end; 1012, second end; 102, conical pipe section; 2, bag; 3, material conveying pipe; 4, stop member; 5, base; 501, grouting channel; 502, pressure relief channel; 5021, first channel opening; 5022, second channel opening; 6, pressure relief valve; 7, filling area; 701, edge coal pillar; 702, middle coal pillar; 703, lower pipe hole; 704, filling hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention, and should not be construed as a limitation of the present invention.

[0033] As Figures 1 to 7 shown, the room-and-pillar goaf cemented filling device 100 of the embodiment of the present invention includes a filling pipe 1 and a bladder 2. The filling pipe 1 includes a straight pipe section 101 and a tapered pipe section 102. The straight pipe section 101 includes a first end 1011 and a second end 1012. The first end 1011 has an opening, and the second end 1012 is connected to the tapered pipe section 102. The cross-sectional area of the tapered pipe section 102 gradually decreases along the direction from the straight pipe section 101 to the tapered pipe section 102. A material passing hole is provided on the pipe wall of the straight pipe section 101. The bladder 2 is arranged around the straight pipe section 101 of the filling pipe 1 for one week. The two ends of the bladder 2 in the axial direction of the filling pipe 1 respectively extend to the edges of the first end 1011 and the second end 1012, and the bladder 2 is communicated with the material passing hole.

[0034] When the room-and-pillar goaf cemented filling device 100 of the embodiment of the present invention is in use, first, the goaf is divided into a plurality of filling areas 7, and the positions of the rib pillars 701 and the middle pillars 702 of each filling area 7 are determined. This step helps to accurately control the use of the filling material and the treatment effect. Then, a pipe hole 703 is drilled between two adjacent rib pillars 701 for inserting the filling pipe 1 into the goaf subsequently. After that, the filling pipe 1 is lowered into the goaf through the pipe hole 703. The tapered pipe section 102 is inserted into the bottom plate of the goaf to fixedly support the filling pipe 1. The first end 1011 of the straight pipe section 101 is placed outside the goaf to ensure the safety of the grouting process. Then, grout is injected into the filling pipe 1 through the first end 1011 of the straight pipe section 101. The slurry entering the filling pipe 1 enters the bladder 2 through the material passing hole, causing the bladder 2 to expand and abut against two adjacent rib pillars 701 to form a preliminary support structure. Wait for the slurry in the bladder 2 to solidify so that the rib pillar 701 and the bladder 2 enclose the filling area 7 to form a sealed space, improving the stability of the goaf. Finally, a filling hole 704 is drilled between two adjacent middle pillars 702, and the sealed space of the filling area 7 is filled with slurry to further consolidate the stability of the goaf.

[0035] The room-and-pillar goaf cemented filling device 100 according to the embodiments of the present invention can effectively improve the stability and safety of the goaf, prevent surface subsidence and strata movement by constructing a room-and-pillar structure and adopting the method of filling with the bladder 2. The sealed space can effectively prevent the slurry in the goaf from overflowing, reducing the pollution to the surrounding water resources and environment. This device is applicable to the already closed room-and-pillar goaf and can play a role in areas with large space and where personnel or equipment are prohibited from entering, solving the problem that traditional filling methods are difficult to apply. Through the step-by-step construction method, the treatment process becomes more standardized and simple, which is beneficial to the improvement of construction efficiency and quality. This technology can reduce material waste in the treatment process, improve the filling efficiency, thereby reducing the treatment cost and having good economic benefits.

[0036] The room-and-pillar goaf cemented filling device 100 according to the embodiments of the present invention provides an effective, safe and environmentally friendly solution, which is of great significance to the safe production of mines and environmental protection.

[0037] In some embodiments, the number of the material passing holes is multiple, and the multiple material passing holes are arranged at intervals along the axial direction of the filling pipe 1.

[0038] For example, as Figure 5 and Figure 7 shown, the multiple material passing holes can help the slurry to be more evenly distributed into the bladder 2, so as to ensure that the bladder 2 can evenly abut against the adjacent edge coal pillar 701 when expanding, forming a stable support. The material passing holes arranged at intervals enable the slurry to be injected into the bladder 2 at multiple points simultaneously, which can accelerate the filling speed and improve the overall construction efficiency. The interval arrangement of the material passing holes can control the flow path and speed of the slurry, helping to prevent the slurry from surging or leaking during the filling process.

[0039] In some embodiments, the room-and-pillar goaf cemented filling device 100 according to the embodiments of the present invention includes a material conveying pipe 3 and a stopper 4. One end of the material conveying pipe 3 passes through the material passing hole and communicates with the bladder 2, and the other end of the material conveying pipe 3 extends into the filling pipe 1. The stopper 4 is arranged on the outer peripheral surface of the material conveying pipe 3 and is located in the filling pipe 1. The stopper 4 is arranged around the material conveying pipe 3 for one week and abuts against the inner wall of the filling pipe 1.

[0040] As Figure 6As shown, one end of the material conveying pipe 3 passes through the material passing hole and communicates with the bladder bag 2, and the other end extends into the filling pipe 1, so that the slurry can be directly fed into the bladder bag 2 through the material conveying pipe 3. The stopper 4 is arranged on the outer peripheral surface of the material conveying pipe 3, located inside the filling pipe 1, surrounding the material conveying pipe 3 for one week, and abuts against the inner wall of the filling pipe 1. The function of the stopper 4 is to fix the bladder bag 2, prevent the material conveying pipe 3 from generating a large radial impact force on the bladder bag 2 during the material conveying process, resulting in the separation of the bladder bag 2 from the filling pipe 1, so as to improve the working reliability of the bladder bag 2. In addition, the presence of the stopper 4 can enhance the connection stability between the material conveying pipe 3 and the filling pipe 1, prevent the material conveying pipe 3 from moving or shifting under the slurry pressure, and ensure the stability of the whole device.

[0041] In some embodiments, a check valve is provided on the material conveying pipe 3, and the outlet of the check valve is arranged towards the bladder bag 2.

[0042] A check valve is a valve that only allows fluid to flow in one direction. Setting a check valve on the material conveying pipe 3 can ensure that the slurry can only flow from the material conveying pipe 3 to the bladder bag 2, preventing the slurry in the bladder bag 2 from flowing back into the material conveying pipe 3. The setting of the check valve effectively prevents the backflow of the slurry, ensures the stability of the filling process, avoids the treatment failure or construction accidents that may be caused by the backflow of the slurry, improves the construction safety, especially in the case of high-pressure grouting, the check valve can effectively prevent the high-pressure slurry from hurting the construction personnel.

[0043] In some embodiments, the room pillar goaf cemented filling device 100 of the embodiment of the present invention further includes a base 5, the base 5 is arranged at the first end 1011 of the straight pipe section 101, the base 5 is annular and coaxially arranged with the filling pipe 1. The outer diameter of the base 5 is larger than the outer diameter of the bladder bag 2, and a grouting channel 501 communicating with the straight pipe section 101 is opened on the base 5.

[0044] As Figure 5 and Figure 6 shown, the base 5 provides additional support, making the whole filling device more stable, and helping to keep the correct position of the device during the filling process. Due to the presence of the base 5, the bladder bag 2 is protected during the filling process, reducing the accidental damage to the bladder bag 2 during the construction process. The annular design of the base 5 helps to guide the flow of the slurry during the filling process of the bladder bag 2, so that the bladder bag 2 can expand more evenly. The grouting channel 501 on the base 5 can be used as a standby or auxiliary grouting path, which helps to quickly switch when there is a problem with the main grouting path, ensuring the continuity and efficiency of the filling. The design of the base 5 makes the installation and operation of the device in the goaf more convenient, reducing the construction difficulty and time. The setting of the base 5 and the grouting channel 501 helps to improve the controllability of the filling process, thereby improving the overall quality of the goaf treatment.

[0045] In some embodiments, as Figure 6As shown in the figure, a pressure relief channel 502 is provided on the base 5. The pressure relief channel 502 has a first channel opening 5021 and a second channel opening 5022. The first channel opening 5021 is communicated with the bladder 2, and a pressure relief valve 6 is provided at the second channel opening 5022. When the grouting pressure in the bladder 2 exceeds a preset value, the pressure relief valve 6 opens.

[0046] The pressure relief channel 502 has a first channel opening 5021 and a second channel opening 5022. The first channel opening 5021 is communicated with the bladder 2, so that the pressure in the bladder 2 can be transmitted through the pressure relief channel 502. A pressure relief valve 6 is provided at the second channel opening 5022. When the grouting pressure in the bladder 2 exceeds a preset value, the pressure relief valve 6 will automatically open to release the pressure in the bladder 2, thus avoiding the danger caused by excessive pressure.

[0047] The design of the pressure relief channel 502 and the pressure relief valve 6 can relieve pressure in time when the pressure in the bladder 2 is too high, effectively preventing safety accidents that may occur during the filling process, such as the rupture of the bladder 2, etc. The pressure in the bladder 2 can be precisely controlled through the pressure relief valve 6 to ensure that the filling process is carried out within a controllable range, improving the controllability of the entire treatment process. It avoids the damage to the performance of the filling material caused by excessive pressure and prolongs the service life of the filling material. The design of the pressure relief channel 502 makes the construction process safer and more reliable, and the construction personnel can carry out the grouting operation with more confidence. The pressure relief valve 6 can adjust the preset pressure value according to actual needs, so that the device can adapt to different geological conditions and filling requirements. The design of the pressure relief channel 502 and the pressure relief valve 6 is convenient for monitoring during the construction process. Once the pressure is abnormal, it can be immediately adjusted through the pressure relief valve 6.

[0048] The present invention also discloses a room-and-pillar goaf cementitious filling method, which is applied to the room-and-pillar goaf cementitious filling device 100 in any of the above embodiments, and includes the following steps:

[0049] S1. Divide the goaf into multiple filling areas 7, and determine the positions of the rib pillars 701 and the middle coal pillars 702 at the edges of each filling area 7;

[0050] S2. Drill pipe holes 703 between two adjacent rib pillars 701;

[0051] S3. Lower the filling pipe 1 into the goaf through the pipe holes 703, insert the conical pipe section 102 of the filling pipe 1 on the bottom plate of the goaf, and place the first end 1011 of the straight pipe section 101 outside the goaf;

[0052] S4. Grout into the filling pipe 1 through the opening at the first end 1011 of the straight pipe section 101, and grout into the bladder 2 by using the filling pipe 1, so that the side of the bladder 2 expands and abuts against two adjacent rib pillars 701;

[0053] S5. Wait for the slurry in the bladder 2 to solidify so that the marginal coal pillar 701 and the bladder 2 enclose the filling area 7 to form a sealed space;

[0054] S6. Drill a filling hole 704 between two adjacent intermediate coal pillars 702, and use the filling hole 704 to fill the sealed space in the filling area 7 with slurry.

[0055] The room-and-pillar goaf cemented filling method according to the embodiment of the present invention can effectively improve the stability and safety of the goaf and prevent surface subsidence and strata movement by constructing a room-and-pillar structure and using the bladder 2 for filling. The sealed space can effectively prevent the slurry in the goaf from overflowing and reduce the pollution to the surrounding water resources and environment. The device is applicable to the already closed room-and-pillar goaf and can play a role in areas with large space and where personnel or equipment are prohibited from entering, solving the problem that traditional filling methods are difficult to apply. Through the step-by-step construction method, the treatment process becomes more standardized and simple, which is conducive to improving the construction efficiency and quality. This technology can reduce material waste during the treatment process, improve the filling efficiency, thereby reducing the treatment cost and having good economic benefits.

[0056] In some embodiments, the bladder 2 is a high-strength wear-resistant nylon cloth bag.

[0057] The high-strength nylon cloth bag can withstand high pressure, which is crucial for ensuring that the bladder 2 does not rupture during the grouting process. During the expansion process of the bladder 2, the tensile resistance of the high-strength nylon cloth bag can prevent damage caused by excessive stretching of the bladder 2. The wear-resistant nylon cloth bag can resist the abrasive particles that may exist in the slurry during the filling process and extend the service life of the bladder 2. When the bladder 2 contacts the goaf coal pillar, the wear-resistant property can prevent damage to the bladder 2 caused by friction. The nylon material has good chemical stability and can resist the erosion of most chemical substances, which is an important property for the bladder 2 that is long-term underground. The high-strength wear-resistant nylon cloth bag can maintain its performance in various environments, including extreme conditions such as wet, high temperature or low temperature.

[0058] In some embodiments, in S5, the time for waiting for the slurry to solidify is greater than or equal to seven days.

[0059] Certain types of slurry may require a longer time to fully solidify and harden to ensure that it reaches the expected strength and stability. Conditions such as underground environmental temperature and humidity may affect the solidification speed of the slurry. Especially in an environment with low temperature or high humidity, the slurry requires more time to solidify. According to the specific situation of the goaf and the treatment requirements, a longer solidification time may be required to ensure that the bladder 2 and the filling material can provide sufficient support force.

[0060] Prolonging the setting time can ensure that the slurry is fully hardened, enhance the supporting force between the bladder 2 and the marginal coal pillar 701, thereby improving the overall stability of the goaf. Before the slurry is completely set, there may be certain safety hazards in the goaf. Prolonging the setting time helps to reduce the risks caused by unstable construction. Reserving sufficient time for the slurry to set can make the construction plan more flexible and provide more adjustment space for the arrangement of other construction steps. The prolonging of the slurry setting time helps to improve the filling quality and ensure that the bladder 2 can fill the goaf evenly and fully.

[0061] In some embodiments, the number of filling holes 704 is multiple and extends in the vertical direction.

[0062] As Figure 2 shown, multiple vertical filling channels help the slurry to be evenly distributed in the filling area 7, reducing the problem of insufficient supporting force caused by uneven slurry. Uniform slurry distribution can improve the overall stability of the goaf and reduce the risks of surface subsidence and strata movement.

[0063] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0064] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0065] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or communicable with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0066] In the present invention, unless otherwise clearly specified or limited, a first feature being "on" or "under" a second feature may mean that the first and second features are in direct contact, or the first and second features are indirectly in contact via an intermediate medium. Moreover, a first feature being "above", "over" and "on top of" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. A first feature being "under", "below" and "beneath" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is less than that of the second feature.

[0067] In the present invention, the terms "an embodiment", "some embodiments", "exemplifications", "specific exemplifications", or "some exemplifications", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or exemplification are included in at least one embodiment or exemplification of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or exemplification. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or exemplifications in a suitable manner. In addition, without conflicting with each other, those skilled in the art may combine and combine the different embodiments or exemplifications described in this specification and the features of different embodiments or exemplifications.

[0068] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A room-and-pillar goaf cementing filling device, characterized in that: include: A filling pipe (1), the filling pipe (1) comprising a straight pipe section (101) and a tapered pipe section (102), the straight pipe section (101) comprising a first end (1011) and a second end (1012), the first end (1011) having an opening, the second end (1012) being connected to the tapered pipe section (102), the cross-sectional area of ​​the tapered pipe section (102) gradually decreasing along the direction from the straight pipe section (101) to the tapered pipe section (102), and a material passing hole being provided on the pipe wall of the straight pipe section (101); and A sac (2), the sac (2) being arranged around the straight tube section (101) of the filling tube (1), the sac (2) extending to the edges of the first end (1011) and the second end (1012) at both ends of the axial direction of the filling tube (1), and the sac (2) being connected to the feed hole.

2. The room-and-pillar goaf cementing filling device according to claim 1 is characterized in that: There are a plurality of the feed holes, and the plurality of the feed holes are arranged at intervals along the axial direction of the filling tube (1).

3. The room-and-pillar goaf cementing filling device according to claim 2, characterized in that: It comprises a feed pipe (3) and a stopper (4), one end of the feed pipe (3) passes through the feed hole to communicate with the bag (2), the other end of the feed pipe (3) extends into the filling pipe (1), the stopper (4) is arranged on the outer peripheral surface of the feed pipe (3) and is located inside the filling pipe (1), the stopper (4) is arranged around the feed pipe (3) and stops on the inner wall of the filling pipe (1).

4. The room-and-pillar goaf cementing filling device according to claim 3 is characterized in that: The feed conveying pipe (3) is provided with a one-way valve, and the outlet of the one-way valve is arranged toward the bag (2).

5. The room-and-pillar goaf cementing filling device according to claim 1, characterized in that: The invention also comprises a base (5), wherein the base (5) is arranged at the first end (1011) of the straight pipe section (101), the base (5) is annular and is coaxially arranged with the filling pipe (1), the outer diameter of the base (5) is greater than the outer diameter of the bladder (2), and the base (5) is provided with a grouting channel (501) connected with the straight pipe section (101).

6. The room-and-pillar goaf cementing filling device according to claim 5, characterized in that: The base (5) is provided with a pressure relief channel (502), the pressure relief channel (502) having a first channel opening (5021) and a second channel opening (5022), the first channel opening (5021) being connected to the bladder bag (2), the second channel opening (5022) being provided with a pressure relief valve (6), and when the grouting pressure in the bladder bag (2) exceeds a preset value, the pressure relief valve (6) opens.

7. A room-and-pillar goaf cementing and filling method, the method being applied to the room-and-pillar goaf cementing and filling device according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1, dividing the goaf into a plurality of filling areas (7), and determining the positions of the edge coal pillars (701) and the middle coal pillars (702) of each of the filling areas (7); S2, drilling a pipe hole (703) between two adjacent edge coal pillars (701); S3, lowering the filling pipe (1) into the goaf through the lower pipe hole (703), inserting the conical pipe section (102) of the filling pipe (1) on the bottom plate of the goaf, and placing the first end (1011) of the straight pipe section (101) outside the goaf; S4, injecting grout into the filling pipe (1) through the opening of the first end (1011) of the straight pipe section (101), and injecting grout into the bag (2) using the filling pipe (1), so that the side of the bag (2) expands and stops on the two adjacent edge coal pillars (701); S5, waiting for the slurry in the bag (2) to solidify, so that the edge coal pillar (701) and the bag (2) enclose the filling area (7) to form a sealed space; S6. Drill a filling hole (704) between two adjacent middle coal pillars (702), and use the filling hole (704) to fill the sealed space of the filling area (7) with slurry.

8. The room-and-pillar goaf cementing filling method according to claim 7, characterized in that: The bag (2) is a high-strength wear-resistant nylon bag.

9. The room-and-pillar goaf cementing filling method according to claim 7, characterized in that: In S5, the time for waiting for the slurry to solidify is greater than or equal to seven days.

10. The room-and-pillar goaf cementing filling method according to claim 7, characterized in that: The filling holes (704) are multiple in number and extend in the vertical direction.

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