Short-wall mining and simultaneous filling mining method and roadway structure

Abstract

The application discloses a short-wall continuous mining and filling mining method, and relates to the technical field of coal mining, which comprises the following steps: S1, two roadways are excavated, one is a filling auxiliary roadway, and the other is a coal mining auxiliary roadway, and the filling auxiliary roadway and the coal mining auxiliary roadway are communicated with an air inlet crossheading and an air return crossheading; S2, coal mining is carried out in a tilt direction between the filling auxiliary roadway and the coal mining auxiliary roadway, and a coal mining roadway is formed; S3, when a second coal mining roadway adjacent to the first coal mining roadway is mined, the first coal mining roadway is filled, and the first coal mining roadway and the second coal mining roadway are always communicated; S4, steps S2 and S3 are repeated; and S5, the filling auxiliary roadway, the coal mining auxiliary roadway, the air inlet crossheading and the air return crossheading are all blocked. The application further discloses a roadway structure formed by using the short-wall continuous mining and filling mining method. The application can avoid the generation of circulating air and improve the safety of mining.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mining, in particular to a short-wall continuous mining and filling mining method and a roadway structure. BACKGROUND

[0002] The continuous mining and filling technology can effectively control surface subsidence and improve resource recovery rate through immediate filling after mining. However, the difficulty of the traditional continuous mining and filling process is ventilation. In the traditional continuous mining and filling process, the headway is usually ventilated by the underground local fan, but this ventilation mode is easy to cause circulating wind, which in turn leads to gas accumulation, seriously threatening safety production. Although the current technology attempts to optimize ventilation, some schemes need to build a complex roadway network to realize zoned ventilation, which greatly increases the roadway excavation engineering quantity and support cost, and is difficult to meet the demand of efficient production. SUMMARY

[0003] The present application relates to the technical field of coal mining, in particular to a short-wall continuous mining and filling mining method and a roadway structure.

[0004] To achieve the above-mentioned purpose, the present application provides the following scheme:

[0005] The present application provides a short-wall continuous mining and filling mining method, comprising the following steps

[0006] S1: two roadways are excavated in the direction perpendicular to the air inlet chute and the air return chute, one of which is a filling auxiliary roadway, and the other is a coal mining auxiliary roadway, the air inlet chute and the air return chute are arranged in parallel, and the filling auxiliary roadway and the coal mining auxiliary roadway are both communicated with the air inlet chute and the air return chute;

[0007] S2: coal mining is carried out in the inclined direction between the filling auxiliary roadway and the coal mining auxiliary roadway to form a coal mining roadway, and the mining direction is from the coal mining auxiliary roadway to the filling auxiliary roadway, wherein the coal transportation path is from the coal mining roadway to the coal mining auxiliary roadway to the air inlet chute;

[0008] S3: when the second coal mining roadway adjacent to the first coal mining roadway is mined, the first coal mining roadway is filled, the filling direction is from the coal mining auxiliary roadway to the filling auxiliary roadway, and the first coal mining roadway and the second coal mining roadway are always communicated, wherein the filling path is from the air return chute to the filling auxiliary roadway to the first coal mining roadway, and the air flow path is from the air inlet chute to the coal mining auxiliary roadway to the second coal mining roadway to the first coal mining roadway to the filling auxiliary roadway to the air return chute;

[0009] S4: repeat steps S2 and S3;

[0010] S5: block the filling auxiliary branch roadway, the coal mining auxiliary branch roadway, the air intake crossheading and the air return crossheading.

[0011] In some embodiments, before step S1, there is further step S101:

[0012] The mining area is divided into multiple work sections according to the total length of the mining area, geological conditions, coal mining efficiency and filling efficiency.

[0013] In some embodiments, the length of the coal mining roadway is the same as the length of the work section, and the width of the coal mining roadway is calculated as follows

[0014]

[0015] In the formula, L is the width of the coal mining roadway, m;

[0016] h is the thickness of the immediate roof, m;

[0017] R t is the shear strength, MPa;

[0018] q is the load borne by the roof beam, kN / m 2 ;

[0019] F0 is the safety factor, and the value range is 2-4;

[0020] The calculation formula of the roof load q is:

[0021]

[0022] In the formula, E1 is the elastic modulus of the immediate roof rock, GPa;

[0023] h1 is the thickness of the immediate roof rock, m;

[0024] p n is the bulk density of the nth overburden, kN / m 3 ;

[0025] h n is the thickness of the nth overburden, m;

[0026] E n is the elastic modulus of the nth overburden, GPa.

[0027] In some embodiments, the included angle between the coal mining roadway and the coal mining auxiliary branch roadway is 70°-80°.

[0028] In some embodiments, the filling device comprises a step-type support and a filling mechanism, and after the step-type support is arranged in place, the goaf of the coal mining roadway is filled by filling concrete into the flexible membrane bag by using the filling mechanism.

[0029] In some embodiments, the top beam of the step support is a parallelogram top beam, and the angle between the two lines is consistent with the angle between the coal mining roadway and the auxiliary mining roadway.

[0030] In some embodiments, a conveyor is arranged in the coal mining roadway, and the coal mining roadway is mined by using a continuous miner, and the spraying dust suppression system and the conveyor are started synchronously when the continuous miner performs the coal cutting process.

[0031] In some embodiments, the working process of the step support is as follows

[0032] S301: After the coal mining of a coal mining roadway is completed, the hydraulic system of the step support is operated to make the first group of columns completely shrink and lift the base, drive the top beam and the base of the first group of columns to move forward by a preset step distance, and after the movement is completed, the first group of columns is kept in a suspended state, and the operation space for erecting the flexible membrane bag and filling the concrete is below the first group of columns;

[0033] S302: The flexible membrane bag is hung on the top beam and the base of the first group of columns in the operation space through the membrane hanging device, and the flexible membrane bag covers the area to be filled;

[0034] S303: The flexible membrane bag is filled with the concrete by using the filling mechanism until it is filled, and initial setting is waited;

[0035] S304: After the initial setting of the concrete is completed, the hydraulic system is operated to make the second group of columns shrink and lift the base, drive the top beam and the base of the second group of columns to move forward by a preset step distance, the second group of columns is aligned with the first group of columns, the second group of columns is lifted and a supporting force is applied after the second group of columns is moved into position, and the side guards on both sides are attached to the two sides of the coal mining roadway;

[0036] S305: Steps S301-S304 are repeated.

[0037] In some embodiments, the concrete comprises 60%-80% of fly ash, 20%-40% of Portland cement, and 0.8%-1.5% of the accelerator, the initial setting time is controlled to be not more than twenty minutes, and the final setting time is controlled to be not more than eight hours.

[0038] The application also provides a roadway structure formed by using the short-wall continuous mining and filling mining method, comprising an air inlet chute, an air return chute, an auxiliary mining roadway, an auxiliary filling roadway, and a coal mining roadway, the air inlet chute and the air return chute are arranged in parallel, the auxiliary mining roadway and the auxiliary filling roadway are arranged in parallel and are perpendicular to the air inlet chute and the air return chute, and the coal mining roadway is arranged obliquely between the auxiliary filling roadway and the auxiliary mining roadway.

[0039] The present application has the following technical effects relative to the prior art:

[0040] The short-wall continuous mining and filling mining method provided by the present application makes the air flow path be from the air inlet gallery to the coal mining auxiliary branch roadway to the second coal mining roadway to the first coal mining roadway to the filling auxiliary branch roadway and then to the air return gallery. In addition, there are two parallel air flow paths, one is from the air inlet gallery to the coal mining auxiliary branch roadway to the air return gallery, and the other is from the air inlet gallery to the filling auxiliary branch roadway to the air return gallery, which can realize full negative pressure ventilation of the coal mining area, prevent the air from flowing back after entering the coal mining roadway to cause whirlwind, and further cause gas accumulation, so that the coal mining is safer; the coal conveying path is from the coal mining roadway to the coal mining auxiliary branch roadway and then to the air inlet gallery; the filling path is from the air return gallery to the filling auxiliary branch roadway and then to the first coal mining roadway; the filling of the coal mining roadway and the transportation of the coal do not affect each other, which can ensure high mining efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0042] Figure 1 It is a plan view of the roadway structure in some embodiments of the present application.

[0043] Figure 2 It is a schematic view of the air flow path in some embodiments of the present application.

[0044] Figure 3 It is a schematic view of the coal conveying path and the filling path in some embodiments of the present application.

[0045] Figure 4 It is a working flowchart of the step-by-step support in some embodiments of the present application.

[0046] Figure 5 It is a layout diagram of the continuous mining machine and the step-by-step support in some embodiments of the present application.

[0047] In the figure: 1-air inlet gallery; 2-air return gallery; 3-filling auxiliary branch roadway; 4-coal mining auxiliary branch roadway; 5-step-by-step support; 6-continuous mining machine; 7-coal mining roadway; 71-first coal mining roadway; 72-second coal mining roadway; 8-filling pipeline; 9-conveyor; 10-concrete; 11-first group of columns; 22-second group of columns. DETAILED DESCRIPTION

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0049] The purpose of this invention is to provide a shortwall continuous mining and filling method and roadway structure to solve the problems existing in the prior art, avoid the generation of circulating air, and improve the safety of mining.

[0050] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] Example 1

[0052] like Figures 1-5 As shown, this invention provides a short-wall continuous mining and backfilling method, comprising the following steps: S1: excavating two roadways perpendicular to the intake airway 1 and the return airway 2, one of which is a backfilling auxiliary roadway 3, and the other is a coal mining auxiliary roadway 4. The intake airway 1 and the return airway 2 are arranged in parallel, and both the backfilling auxiliary roadway 3 and the coal mining auxiliary roadway 4 are connected to the intake airway 1 and the return airway 2; S2: mining coal in an inclined direction between the backfilling auxiliary roadway 3 and the coal mining auxiliary roadway 4 to form a coal mining roadway 7, wherein the mining direction is from the coal mining auxiliary roadway 4 to the backfilling auxiliary roadway 3, and the coal transportation path is a coal conveyor starting from the coal mining auxiliary roadway 4 and ending at the backfilling auxiliary roadway 3. S3: When mining the second coal mining roadway 72 adjacent to the first coal mining roadway 71, the first coal mining roadway 71 is backfilled. The backfilling direction starts from the coal mining auxiliary branch roadway 4 and ends at the backfilling auxiliary branch roadway 3. The first coal mining roadway 71 and the second coal mining roadway 72 are always connected. The backfilling path is from the backfilling equipment from the return air roadway 2 to the backfilling auxiliary branch roadway 3 and then to the first coal mining roadway 71. The airflow path is from the inlet air roadway 1 to the coal mining auxiliary branch roadway 4 to the second coal mining roadway 72 to the first coal mining roadway 71 to the backfilling auxiliary branch roadway 3 and then to the return air roadway 2. In addition, there are two parallel airflow paths: one is from intake roadway 1 to coal mining auxiliary branch roadway 4 to return air roadway 2; the other is from intake roadway 1 to filling auxiliary branch roadway 3 to return air roadway 2. This can achieve full negative pressure ventilation in the coal mining area, prevent the wind from flowing back after entering the coal mining roadway 7 and causing swirling wind, which in turn causes gas accumulation, making coal mining safer; S4: Repeat steps S2 and S3; S5: Block all filling auxiliary branch roadway 3, coal mining auxiliary branch roadway 4, intake roadway 1 and return air roadway 2.

[0053] In some embodiments, before step S1, there is further a step S101 of dividing the mining area into a plurality of working sections according to the total length of the mining area, geological conditions, coal mining efficiency and filling efficiency, and it is to be noted that the first working section takes the open-off cut as the filling auxiliary roadway 3. The length of the working section should not be too long to avoid increasing the supporting difficulty, and when the walking supports 5 are used for auxiliary support, the length of the working section is usually set to be close to the sum of the lengths of four to six walking supports 5. Different geological conditions have a great impact on the coal mining operation. By dividing the working sections, the coal mining and filling process parameters can be flexibly adjusted according to the specific geological conditions of each region, such as the coal seam thickness variation, the roof and floor stability, the geological structure complexity and the like, to ensure that the mining operation is safe and efficient. For example, in the section with poor geological conditions, the length of the working section can be appropriately shortened, the supporting measures can be strengthened, and the mining risk can be reduced; while in the region with good geological conditions, the length of the working section can be appropriately lengthened, and the coal mining efficiency can be improved. The shorter working section means that the supporting range of the support is relatively small, and when facing the roof pressure, the support can more effectively play a supporting role, reducing the risk of roof deformation and collapse. Moreover, during the movement and adjustment of the support, it is more flexible and convenient, which is beneficial to supporting the newly exposed roof in time, and ensuring the safety of the underground operation personnel.

[0054] In some embodiments, the length of the coal mining roadway 7 sinθ (θ is the angle between the coal mining roadway and the coal mining auxiliary roadway) = working section length, the width of the first coal mining roadway 71 and the second coal mining roadway 72 parallel to each other should be determined by considering the roof control distance and the mining-induced stress and the like, and the width of the coal mining roadway 7 is calculated as follows

[0055]

[0056] In the formula, L is the width of the coal mining roadway, m;

[0057] h is the thickness of the immediate roof, m;

[0058] R t is the shear strength, MPa;

[0059] q is the load borne by the roof beam, kN / m 2 ;

[0060] F0 is the safety factor (the value range is 2-4).

[0061] The calculation formula of the roof beam load q is:

[0062]

[0063] In the formula, E1 is the elastic modulus of the immediate roof rock, GPa;

[0064] h1is the thickness of the immediate roof, m;

[0065] p n is the bulk density of the nth layer of overburden, kN / m 3 ;

[0066] h n is the thickness of the nth layer of overburden, m;

[0067] E n is the elastic modulus of the nth layer of overburden, GPa.

[0068] The above formula combines the comprehensive calculation of multiple parameters to more accurately reflect the geomechanical environment in which the roadway is located, thereby determining a more scientific and reasonable roadway width and ensuring the stability of the roadway during the mining process. Moreover, the introduction of the safety factor F0 (value range 2-4) provides additional protection for the safety of the roadway, which can take into account some uncertain factors that are difficult to accurately calculate, such as local changes in geological conditions, dynamic loads during the mining process, etc. This makes the calculated roadway width able to meet the requirements of roadway support and safety production in various possible situations, effectively reducing the risk of safety accidents such as roadway collapse.

[0069] In some embodiments, the angle between the coal mining roadway 7 and the coal mining auxiliary branch roadway 4 is 70°-80°. For the coal transportation and mining path, this angle setting enables the coal transporters and continuous mining machines 6 to operate more efficiently between the coal mining roadway 7 and the coal mining auxiliary branch roadway 4, and also facilitates the work of the step-type supports 5. For example, in the process of inclined mining, the transportation process of the coal transporters from the coal mining roadway 7 to the coal mining auxiliary branch roadway 4 and then to the air intake crossheading 1 is smoother, reducing the turning resistance and angle limitations of the coal transporters in the transportation process and the continuous mining machines 6 in the mining process, and improving the efficiency of coal transportation and mining.

[0070] In some embodiments, the filling device comprises a step-by-step support 5 and a filling mechanism, after the step-by-step support 5 is arranged in place, the filling mechanism fills the goaf of the coal mining roadway 7 by filling the pipe 8 with the flexible membrane bag and the concrete 10, and the step-by-step support 5 is used for auxiliary support to avoid the use of anchor net support and the like, thereby reducing the cost and being simple to operate. The step-by-step support 5 directly replaces traditional support materials such as anchor rods, metal nets, and anchor cables, thereby avoiding the purchase, transportation, and installation costs of such materials. Taking anchor rod support as an example, the traditional coal mining roadway 7 needs to consume multiple anchor rods and supporting trays and nuts per meter, and needs to be drilled and installed by professional equipment, while the step-by-step support 5 can be reused without continuous investment in consumables, and long-term application can significantly reduce the single-lane support cost. The anchor rod net support needs to be equipped with an anchor rod drilling machine, tensioning equipment, and the like, and needs to be drilled, installed, and fastened by a dedicated person, which is a complicated process with high labor costs; the step-by-step support 5 is driven by a hydraulic drive to achieve rapid movement and positioning, and the operation process is simplified, without the need for additional investment in support special equipment and labor, thereby further reducing the operation cost. After the step-by-step support 5 is arranged in place, the filling mechanism can directly fill the flexible membrane bag with the concrete 10 relying on the stable space formed by the support, without the need to wait for the completion of the traditional support construction before carrying out the filling operation, thereby realizing seamless connection between the support and the filling process, reducing the process interval time, and improving the single-lane filling efficiency. The step-by-step support 5 adopts a hydraulic step-by-step movement mode, can be pushed forward as a whole without disassembly, can flexibly adjust the support position according to the filling progress of the coal mining roadway 7, is particularly suitable for the dynamic operation mode of mining and filling one section at a time in short-wall continuous mining and filling, avoids the complicated process of disassembly and reconstruction of traditional support, and saves operation time.

[0071] In some embodiments, the top beam of the step-by-step support 5 is a parallelogram top beam, and the angle between the two line edges is consistent with the angle between the coal mining roadway 7 and the coal mining auxiliary branch roadway 4, and the direction of the step-by-step advancement is perpendicular to the direction of the extension of the crossheading. The angle between the line edges of the parallelogram top beam is consistent with the angle between the coal mining roadway 7 and the coal mining auxiliary branch roadway 4, which can better fit the actual shape of the roadway and make full use of the space of the roadway. This makes the support in the support process more closely contact with the roadway wall, can effectively reduce the support blind area, improve the support effect, and at the same time, provides more sufficient space for the operation of the coal mining equipment and personnel in the roadway, facilitates operation and passage, and the support adopts a widened top beam, which can reduce the amount of support in a single roadway.

[0072] In some embodiments, a conveyor 9 is arranged in the coal mining roadway 7, and the coal mining roadway 7 is mined by using the continuous miner 6. When the continuous miner 6 performs the coal cutting process, the spray dust suppression system and the conveyor 9 are started synchronously. While the continuous miner 6 cuts coal, the conveyor 9 is operated synchronously, which can timely transport the cut coal out of the coal mining roadway 7, avoid the accumulation of coal in the coal mining roadway 7, ensure that the continuous miner 6 can continuously and uninterruptedly cut coal, reduce the downtime caused by waiting for transportation, and thus improve the production efficiency of the entire coal mining process. On the one hand, the synchronous start of the spray dust suppression system can effectively suppress the source of dust. When the continuous miner 6 cuts coal, a large amount of dust will be generated. The spray dust suppression system can adsorb and wrap dust particles by spraying water mist, so that the dust particles can be settled, the dust concentration in the air can be reduced, the harm of dust to the respiratory system of workers can be reduced, the working environment can be improved, and the health of workers can be protected. On the other hand, the synchronous operation of the conveyor 9 and the continuous miner 6 can avoid safety hazards caused by the accumulation of coal, such as preventing the accumulation of too much coal from increasing the pressure of the roadway roof and reducing the risk of roadway collapse, and reducing the possibility of spontaneous combustion caused by the accumulation of coal. It should be noted that the coal mining equipment should use a heading machine and the continuous miner 6 (continuous miner), the coal conveying equipment should use a loader, a shuttle car, a belt conveyor, a scraper conveyor, etc., and the conveying capacity of the coal conveying equipment should be matched with the production capacity of the coal mining equipment to ensure continuous and efficient coal mining operation.

[0073] As Figure 4As shown, in some embodiments, the working process of the step-by-step support 5 is as follows S301: the specific process is step a, step b, step c, step d, step e, step f in turn, after a coal mining roadway 7 is completed, the hydraulic system of the step-by-step support 5 is operated, so that the first group of columns 11 is completely retracted and unloaded, and the base is lifted, at this time the weight of the top beam and the pressure of the roof are completely borne by the second group of columns 22, the top beam and the base of the first group of columns 11 are driven to move forward by a preset step distance (equal to the width of the flexible membrane bag), after the movement is completed, the first group of columns 11 remains in a suspended state, and the operation space for erecting the flexible membrane bag and filling the concrete 10 is below the first group of columns 11; S302: the flexible membrane bag is hung on the top beam and the base (or a special hook) of the first group of columns 11 through the membrane hanging device in the operation space, and the flexible membrane bag covers the area to be filled, including the roof, the two sides and the floor; S303: the concrete 10 is filled into the flexible membrane bag by using the filling mechanism until it is filled, and initial setting is waited for, so that it can bear part of the pressure of the roof; S304: after the initial setting of the concrete 10 is completed, the hydraulic system is operated to make the second group of columns 22 retract and unload, and the base is lifted, at this time the pressure of the roof is borne by the setting concrete 10 and the first group of columns 11, the top beam and the base of the second group of columns 22 are driven to move forward by a preset step distance, the second group of columns 22 is aligned with the first group of columns 11, the second group of columns 22 is lifted and a supporting force is applied after the second group of columns 22 is moved into position, and the side protection plates on both sides are attached to the two sides of the coal mining roadway 7; S305: steps S301-S304 are repeated. Figure 4 As shown, step a: initial state; step b: the first group of columns 11 is completely retracted and unloaded; step c: the top beam and the base of the first group of columns 11 move forward by a preset step distance; step d: the first group of columns 11 remains in a suspended state; step e: the first group of columns 11 supports, and the second group of columns 22 is retracted and unloaded and the base is lifted; step f: the second group of columns 22 is lifted and a supporting force is applied after being moved into position, and returns to the initial state.

[0074] It should be noted that the filling mechanism includes a crusher, a screening machine, a feeder, a mixing device and a water pump. In addition, the filling pump is used as an optional device to provide a pressurized conveying force. When the required pressure for conveying the concrete 10 at the system outlet is greater than or equal to 2 MPa, the filling pump needs to be added to ensure the smooth conveying of the concrete 10 and to ensure the forming quality of the concrete 10. The length, width and height of the flexible membrane bag are determined according to the walking support parameters and the size of the roadway: the length is matched with the width of the walking support, the width is equal to the single walking distance of the walking support, and the height is equal to the height of the roadway. The top and both sides of the flexible membrane bag are provided with a film hanging device, which is designed with the core principle of convenient operation to ensure that it can be quickly and stably hung on the walking support. At the same time, the flexible membrane bag is made of high-strength and low-elongation synthetic fibers (such as polypropylene and polyester), which has excellent properties such as wear resistance, puncture resistance (top burst resistance), anti-aging, high tensile strength and flame resistance, thereby ensuring the forming quality of the filling body and the construction safety.

[0075] In some embodiments, the concrete 10 includes 60%-80% fly ash, which is a waste material of coal-fired power plants, and a large amount of fly ash can replace part of the cement to reduce the amount of cement, thereby reducing production costs, realizing waste utilization and meeting the requirements of sustainable development, 20%-40% Portland cement, which provides basic cementitious strength, and 0.8%-1.5% accelerator (such as sodium aluminate), which controls the initial setting time to be not greater than twenty minutes and the final setting time to be not greater than eight hours.

[0076] Embodiment two

[0077] The embodiment also provides a roadway structure formed by the short-wall continuous mining and filling mining method in embodiment one, which includes an air inlet gallery 1, an air outlet gallery 2, a coal mining auxiliary branch roadway 4, a filling auxiliary branch roadway 3 and a coal mining roadway 7. The air inlet gallery 1 and the air outlet gallery 2 are arranged in parallel, the coal mining auxiliary branch roadway 4 and the filling auxiliary branch roadway 3 are arranged in parallel and are perpendicular to the air inlet gallery 1 and the air outlet gallery 2, and the coal mining roadway 7 is arranged obliquely between the filling auxiliary branch roadway 3 and the coal mining auxiliary branch roadway 4. The roadway structure naturally forms a main ventilation path from the air inlet gallery 1 to the coal mining auxiliary branch roadway 4 to the coal mining roadway 7 to the filling auxiliary branch roadway 3 to the air outlet gallery 2, and relies on the parallel auxiliary branch roadways to form a parallel standby path from the air inlet gallery 1 to the coal mining auxiliary branch roadway 4 or from the filling auxiliary branch roadway 3 to the air outlet gallery 2. The multi-path and closed-loop ventilation layout can ensure the one-way flow of air flow in the coal mining roadway 7 and avoid air flow backflow (circulating air) caused by unreasonable roadway trend, thereby eliminating the hidden danger of gas accumulation from the spatial structure.

[0078] The principles and implementation manners of the present application are described by using specific examples in the present application, and the above examples are only used for helping to understand the method of the present application and its core idea; meanwhile, for the general technical personnel in the art, according to the idea of the present application, the specific implementation manners and application ranges will be changed. In conclusion, the content of the present specification should not be understood as the limitation of the present application.

Claims

1. A shortwall mining and simultaneous backfilling method, characterized in that: The method comprises the following steps S1: excavating two tunnels in a direction perpendicular to the air inlet channel and the air return channel, one of which is a filling auxiliary branch tunnel and the other is a coal mining auxiliary branch tunnel, the air inlet channel and the air return channel are arranged in parallel, and the filling auxiliary branch tunnel and the coal mining auxiliary branch tunnel are communicated with the air inlet channel and the air return channel; S2: mining coal in a direction inclined between the filling auxiliary branch tunnel and the coal mining auxiliary branch tunnel to form a coal mining tunnel, and the mining direction is from the coal mining auxiliary branch tunnel to the filling auxiliary branch tunnel, wherein the coal conveying path is from the coal mining tunnel to the coal mining auxiliary branch tunnel and then to the air inlet channel; S3: when mining a second coal mining tunnel adjacent to a first coal mining tunnel, filling the first coal mining tunnel, the filling direction is from the coal mining auxiliary branch tunnel to the filling auxiliary branch tunnel, and the first coal mining tunnel is always communicated with the second coal mining tunnel, wherein the filling path is from the air return channel to the filling auxiliary branch tunnel and then to the first coal mining tunnel, the air flow path is from the air inlet channel to the coal mining auxiliary branch tunnel to the second coal mining tunnel to the first coal mining tunnel to the filling auxiliary branch tunnel and then to the air return channel; S4: repeating steps S2 and S3; S5: sealing the filling auxiliary branch tunnel, the coal mining auxiliary branch tunnel, the air inlet channel and the air return channel.

2. The shortwall mining and simultaneous backfilling method according to claim 1, characterized in that: Before step S1, step S101 is further included The mining area is divided into multiple work sections according to the total length of the mining area, geological conditions, coal mining efficiency and filling efficiency.

3. The shortwall mining and simultaneous backfilling method according to claim 2, characterized in that: The width of the coal mining tunnel is calculated as follows In the formula: L is the width of the coal mining tunnel, m; h is the thickness of the immediate roof, m; R t For shear strength, MPa; q is the load on the roof beam, kN / m 2 ; F0 is the safety factor, the value range is 2-4; The calculation formula of the roof load q is: In the formula: E1 is the elastic modulus of the immediate roof, GPa; h1 is the thickness of the immediate roof, m; p n Bulk density of the nth layer of overburden, kN / m 3 ; h n h is the thickness of the nth layer of overburden, m; E n Elastic modulus of the nth layer of overburden rock, GPa.

4. The shortwall mining and simultaneous backfilling method according to claim 1, characterized in that: The angle between the coal mining tunnel and the coal mining auxiliary branch tunnel is 70°-80°.

5. The shortwall mining and simultaneous backfilling method according to claim 1, characterized in that: The filling device comprises a step-type support and a filling mechanism, and the step-type support is arranged in place, and the filling mechanism is used to fill the concrete into the flexible membrane bag to fill the goaf of the coal mining tunnel.

6. The shortwall mining and simultaneous backfilling method according to claim 5, characterized in that: The top beam of the step-type support is a parallelogram top beam, and the angle between the two line edges is consistent with the angle between the coal mining tunnel and the coal mining auxiliary branch tunnel.

7. The shortwall mining and simultaneous backfilling method according to claim 1, characterized in that: A conveyor is arranged in the coal mining tunnel, and the coal mining tunnel is mined by using a continuous miner, and when the continuous miner performs the coal cutting process, a spray dust suppression system and the conveyor are started synchronously.

8. The shortwall mining and simultaneous backfilling method according to claim 5, characterized in that: The working process of the step-type support is as follows S301: after the coal mining of one coal mining tunnel is completed, the hydraulic system of the step-type support is operated, so that the first group of columns are completely contracted and unloaded, the base is lifted, the top beam and the base of the first group of columns are driven to move forward by a preset step distance, after the movement is completed, the first group of columns remain in a suspended state, and the operation space for erecting the flexible membrane bag and filling the concrete is below the first group of columns; S302: the flexible membrane bag is hung on the top beam and the base of the first group of columns in the operation space through the membrane hanging device, and the flexible membrane bag covers the to-be-filled area; S303: the filling mechanism is used to fill the concrete into the flexible membrane bag until it is filled, and initial setting is waited. S304: After the initial setting of the concrete is completed, the hydraulic system is operated to make the second group of columns contract and unload pressure, and lift the base, drive the top beam and the base of the second group of columns to move forward by a preset step distance, the second group of columns is aligned with the first group of columns, the second group of columns is lifted and a supporting force is applied after being moved into position, and the side guard plates on both sides are in contact with the two sides of the coal mining roadway; S305: Repeat steps S301-S304.

9. The shortwall mining and simultaneous backfilling method according to claim 5, characterized in that: The concrete includes 60%-80% fly ash, 20%-40% Portland cement, and 0.8%-1.5% accelerator, the initial setting time is controlled to be not more than twenty minutes, and the final setting time is not more than eight hours.

10. A roadway structure formed using the shortwall mining and simultaneous backfilling method according to any one of claims 1 to 9, characterized in that: The coal mining roadway is obliquely arranged between the filling auxiliary branch roadway and the coal mining auxiliary branch roadway.

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