Method for leaving roadways in a single-roadway, steeply inclined, thick coal seam fully mechanized longwall face

Abstract

This invention discloses a method for leaving a roadway in a steeply inclined thick coal seam longwall mining face with a single roadway, relating to the field of coal mine steeply inclined thick coal seam mining technology. The method includes: excavating the roadway cross-section along the floor of the steeply inclined thick coal seam, excavating along the coal seam strike, and penetrating the return air incline and transport incline. The roadway is supported by transverse and longitudinal I-beams and equipped with individual hydraulic props. Coal resources adjacent to the roadway are mined; after the coal resources are mined, hydraulic supports for top coal caving are deployed for top coal caving mining. After the top coal caving is completed, the coal resources in front of the supports are mined, and the supports are moved forward to cave the top coal, repeating the mining-moving-caving cycle. After the working face advances, the roadway behind the working face is densely maintained with individual hydraulic props. Simultaneously, yellow mud slurry is injected into the floor of the goaf behind the working face. This invention only requires excavating one roadway, ensuring good ventilation at the working face and preventing spontaneous combustion of residual coal in the goaf.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steeply inclined thick coal seam mining, in particular to a single roadway steeply inclined thick coal seam fully mechanized caving face roadway setting method. BACKGROUND

[0002] Steeply inclined coal resources are high-quality coal resources, but there are still some problems in the mining process: such as high roadway excavation rate, poor ventilation condition, and easy spontaneous combustion in the goaf after mining.

[0003] The above-mentioned high roadway excavation rate mainly exists in the inclined, small segmented blasting and shield support along the inclined advancing mining methods, and a considerable part of the roadway is excavated and maintained in the abutment pressure zone. The workload of maintaining these roadways is large, the excavation rate is high, and the cost of roadway excavation and maintenance is increased; the poor ventilation condition also exists in various mining methods to different degrees, and the ventilation system of some mining methods is complex, and some mining faces are single-end ventilation, the coal dust and gas content in the working face airflow is high, which is harmful to the health and safety of the workers. In addition, the coal in the goaf is easy to spontaneous combustion, which undoubtedly increases the safety risk.

[0004] Therefore, the above-mentioned prior art still needs to be further improved. SUMMARY

[0005] The purpose of the present application is to provide a single roadway steeply inclined thick coal seam fully mechanized caving face roadway setting method, which only excavates one roadway, and can prevent spontaneous combustion of residual coal in the goaf under the premise of ensuring good ventilation of the working face.

[0006] In order to achieve the above-mentioned purpose, the following technical solutions are adopted in the present application:

[0007] A single roadway steeply inclined thick coal seam fully mechanized caving face roadway setting method, comprising the following steps in sequence:

[0008] S1, excavating a roadway in the rock along the steeply inclined thick coal seam floor, forming a right triangle with one side being the coal seam and three sides being the rock, and simultaneously, excavating a slot inward at the upper corner of the excavated roadway;

[0009] S2, laying a metal net on the roof of the excavated roadway, and setting a transverse I-beam at the lower part of the metal net, one end of the transverse I-beam being inserted into the slot and being supported by the rock at the lower part of the slot;

[0010] S3, reinforcing the transverse I-beam with an anchor rod;

[0011] S4, continuing to excavate along the cross section direction of the roadway until the transport uphole and the return air uphole are connected, forming a ventilation system;

[0012] S5. After the roadway is completed, the coal next to the roadway is mined at the uphill end of the transport roadway. The mining height is the same as that of the roadway. Then, hydraulic supports for caving the top coal are installed to mine the top coal above the working face.

[0013] S6. After the coal is discharged, the coal in front of the top coal caving hydraulic support is mined at the same height as the roadway. The adjacent top coal caving hydraulic supports advance forward through mutual interaction, and then the top coal is discharged. The roadway behind the working face is densely reinforced with single hydraulic props.

[0014] S7. Repeat steps S5 and S6 in sequence. After the working face advances a certain distance, set up grouting pipes on the bottom plate of the goaf and inject yellow mud slurry into the bottom plate of the goaf through the grouting pipes. The injected yellow mud slurry covers the residual coal in the goaf.

[0015] S8. After the working face has advanced a certain distance, that is, after the overburden collapses and stabilizes, the individual hydraulic props within the stable overburden area are retrieved. After the individual props are retrieved, they are reinforced with wooden supports in a timely manner. As the working face continues to advance, the individual hydraulic props are gradually retrieved.

[0016] As a preferred embodiment of the present invention, in step S3, the anchor bolts are vertically anchored in the roof of the roadway, and the roadway sidewalls of the rock strata are also vertically supported by the anchor bolts.

[0017] As another preferred embodiment of the present invention, in step S4, a single hydraulic prop is used to support the transverse H-beam, and a longitudinal H-beam parallel to the roadway is set above the single prop. The transverse H-beam is set above the longitudinal H-beam, and the other end of the transverse H-beam is supported by the longitudinal H-beam.

[0018] In a further preferred embodiment, the grouting pipes are arranged in a plurality of evenly spaced sections.

[0019] Yellow mud slurry is injected into the floor of the goaf through multiple grouting pipes. The amount of yellow mud slurry injected must completely cover the remaining coal in the goaf to prevent it from spontaneously combusting.

[0020] Preferably, several of the top coal caving hydraulic supports are arranged side by side.

[0021] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0022] This invention proposes a method for leaving a roadway in a single-roadway fully mechanized longwall face with steeply inclined thick coal seams. This method only requires the excavation of one roadway, reducing the amount of roadway excavation, and can also ensure full-pressure air intake at the working face and two safety exits on both sides of the working face.

[0023] After the working face has advanced a certain distance, yellow mud slurry is used to grout the floor of the goaf, which can encapsulate the remaining coal and prevent spontaneous combustion. The reserved roadways do not require special windbreak structures, and fresh air entering the goaf does not come into contact with the remaining coal.

[0024] In this invention, the roadway is arranged on the floor of a steeply inclined thick coal seam, which results in high roadway safety and ease of maintenance compared to roadways arranged on the roof of a steeply inclined thick coal seam in the prior art.

[0025] This invention makes full use of the characteristics of steeply inclined thick coal seams, and adopts a horizontal mining method to facilitate the placement of various equipment. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings:

[0027] Figure 1 This is a schematic cross-sectional view of the tunnel layout of the present invention;

[0028] Figure 2 This is a schematic diagram of the tunnel layout of the present invention;

[0029] Figure 3 This is a schematic diagram of the working face mining profile;

[0030] Figure 4 This is a schematic diagram of the working face mining plan;

[0031] Figure 5 Schematic diagram of yellow mud grouting;

[0032] In the picture:

[0033] 1. Coal seam roof, 2. Steeply inclined thick coal seam, 3. Coal seam floor, 4. Horizontal I-beam, 5. Slotting, 6. Anchor bolt, 7. Longitudinal I-beam, 8. Single hydraulic prop, 9. Roadway, 10. Top coal caving hydraulic support, 11. Fresh air flow, 12. Air door, 13. Transport uphill, 14. Return air uphill, 15. Sludge, 16. Yellow mud, 17. Grouting pipe. Detailed Implementation

[0034] This invention proposes a method for leaving roadways in a single-roadway steeply inclined thick coal seam fully mechanized longwall mining face. To make the advantages and technical solutions of this invention clearer and more explicit, the invention will be further described below with reference to specific embodiments.

[0035] The thickness of the "sharply inclined thick coal seam" mentioned in this invention is 3 to 8 meters.

[0036] The "yellow mud slurry" mentioned in this invention refers to a slurry made by mixing water and soil in an appropriate proportion. This slurry is injected into the goaf floor through a grouting pipe 17 connected to a grouting pipeline. After being injected into the goaf, the yellow mud slurry gradually flows into the gaps, filling the goaf. The yellow mud slurry encapsulates the coal, preventing it from spontaneously combusting. The moisture in the yellow mud slurry also inhibits spontaneous combustion of the coal.

[0037] The main technical concept of this invention is to ensure full-pressure ventilation at the working face while reducing the workload of tunneling, and also to prevent spontaneous combustion of coal in the goaf. Therefore, taking advantage of the characteristics of steeply inclined thick coal seams, this invention studies roadway retention methods, combined support methods, and mining methods, and proposes a single-roadway roadway retention method for steeply inclined thick coal seam fully mechanized longwall mining faces, such as... Figure 1 As shown in the figure, the coal seam roof 1, steeply inclined thick coal seam 2, coal seam floor 3, transverse I-beam 4, cut-out 5, anchor bolt 6, longitudinal I-beam 7, single hydraulic prop 8, and roadway 9 are shown. There are multiple anchor bolts 6. The dimensions of transverse I-beam 4 and longitudinal I-beam 7 are selected according to the actual situation. The structure and working method of the single hydraulic prop can refer to existing technology.

[0038] like Figure 2 As shown, the transport uphill section 13 and the return air uphill section 14 are shown, with the damper 12 installed on the transport uphill section 13.

[0039] This invention discloses a method for reserving roadways behind a steeply inclined thick coal seam top-coal caving working face. The roadway is excavated along the bottom plate of the steeply inclined thick coal seam, following the coal seam strike, and penetrating the return air incline and transport incline. The roadway is supported by transverse and longitudinal I-beams and individual hydraulic props. Coal resources adjacent to the roadway are mined, with the mining direction along the horizontal direction of the true thickness of the coal seam. After the coal resources are mined, top-coal caving hydraulic supports are deployed for top-coal caving mining. After the top-coal caving is completed, the coal resources in front of the supports are mined, and then the supports are moved forward to continue caving the top-coal, repeating the mining-moving-top-coal caving cycle. As the working face advances, dense maintenance of the roadway behind the working face is carried out with individual hydraulic props. Simultaneously, yellow mud slurry is injected into the floor of the goaf behind the working face to isolate the remaining coal from the air. As the working face continues to advance, when the mine pressure in the roadway behind the working face becomes less obvious, the individual hydraulic props are retrieved and replaced with wooden props until all individual hydraulic props are retrieved.

[0040] Specifically, a method for leaving a roadway in a single-roadway, steeply inclined, thick coal seam fully mechanized longwall mining face includes the following steps:

[0041] Step 1: Horizontally excavate roadways into the rock strata at 3 points along the bottom plate of the steeply inclined thick coal seam, forming a right-angled trapezoid with one side being the coal seam and the other three sides being the rock strata. At the same time, cut a groove 5 inward at the upper corner of the roadway formed by the excavation.

[0042] Step 2: Lay a metal mesh on the roof of the tunnel formed by excavation, and set a transverse I-beam 4 at the bottom of the metal mesh. One end of the transverse I-beam is inserted into the cut and supported by the rock strata below the cut.

[0043] Step 3: Use anchor bolts to reinforce the transverse I-beams. Anchor bolts are vertically anchored in the roof of the roadway. At the same time, anchor bolts are used to vertically support the roadway sides of the rock strata.

[0044] Step 4: Continue excavation along the cross-section of the tunnel until the transport uphill section 13 and the return air uphill section 14 are connected, forming a ventilation system that facilitates the flow of fresh air 11. Figure 3 As shown, a single hydraulic prop is used to support the transverse H-beam. A longitudinal H-beam parallel to the roadway is also set above the single prop. The transverse H-beam is set above the longitudinal H-beam, and the other end of the transverse H-beam is supported by the longitudinal H-beam.

[0045] Step 5: After the roadway is connected, the coal next to the roadway is mined at the uphill end of the transport roadway. The mining height is the same as the roadway height. Then, hydraulic supports for caving the top coal are set up to cavitate the top coal above the working face.

[0046] Step 6: After the coal is discharged, the coal in front of the top coal caving hydraulic support 10 is mined at the same height as the roadway. The adjacent top coal caving hydraulic supports advance forward through mutual interaction, and then the top coal is discharged. The roadway behind the working face is densely reinforced with single hydraulic props.

[0047] Step 7: Repeat steps 5 and 6 in sequence. After the working face advances a certain distance, grouting pipes are set in the bottom plate of the goaf. Multiple grouting pipes are evenly spaced. Yellow mud slurry is injected into the bottom plate of the goaf through grouting pipe 17, and the yellow mud slurry 16 is used to cover the residual coal.

[0048] Step 8: After the working face has advanced a certain distance, that is, after the overburden collapses and stabilizes, the individual hydraulic props within the stable overburden area are retrieved. After the individual hydraulic props are retrieved, they are reinforced with wooden supports in a timely manner. As the working face continues to advance, the individual hydraulic props are gradually retrieved.

[0049] like Figure 5 As shown, several grouting pipes are evenly spaced. The specific number can be selected by those skilled in the art based on the actual situation. Grout is injected into the goaf floor through each grouting pipe. Yellow mud slurry is injected into the goaf floor through multiple grouting pipes. The amount of yellow mud slurry injected should completely cover the residual coal in the goaf to prevent spontaneous combustion.

[0050] like Figure 4As shown in the schematic diagram of the working face, fresh airflow 11 enters the working face and finally forms waste airflow 15 for discharge. The entry of fresh airflow and the discharge of waste air can ensure good ventilation of the working face.

[0051] The present invention will be further described below with reference to specific embodiments.

[0052] Example 1:

[0053] Step 1: Horizontally excavate a roadway into the rock strata along the bottom of the steeply inclined thick coal seam, forming a right-angled trapezoid with one side being the coal seam and the other three sides being the rock strata. At the same time, cut a groove inward at the upper corner of the roadway, with the groove size slightly larger than the cross-section of the I-beam.

[0054] Step 2: Lay metal mesh on the roof of the trapezoidal tunnel. Choose a sturdy and durable metal mesh with a square or rectangular mesh structure to enhance safety. A transverse I-beam is installed under the metal mesh. One end of the transverse I-beam is inserted into the upper corner of the tunnel and supported by the rock strata below the corner. The other end is supported by the longitudinal I-beam above the single hydraulic prop.

[0055] Step 3: Reinforce the I-beams with anchor bolts, which are vertically anchored into the tunnel roof. Anchor bolts are also used for vertical support of the tunnel sides in the rock strata, resulting in a more stable support method.

[0056] Step 4: Continue excavating along the cross-section of the tunnel until the haulage uphill and return air uphill are connected, forming a ventilation system. Individual hydraulic props are used to support the H-beams, with longitudinal H-beams parallel to the tunnel installed above each prop, and transverse H-beams installed above the longitudinal H-beams.

[0057] Step 5: After the roadway is completed, coal is mined at the uphill end of the transport roadway, at the same height as the roadway. Then, hydraulic supports for releasing top coal are installed and laid side by side to release the top coal above the working face.

[0058] Step Six: After coal release is complete, the coal in front of the supports is mined at the same height as the roadway. The top coal hydraulic supports advance forward through mutual interaction, and then top coal release continues. The roadway behind the working face is densely reinforced with individual hydraulic props.

[0059] Step 7: Repeat steps 5 and 6 in sequence. After the working face advances a certain distance, install perforated pipes in the goaf floor and inject yellow mud slurry into the goaf floor through the perforated pipes. The amount of yellow mud slurry injected is enough to cover the remaining coal.

[0060] Step 8: After the working face has advanced a certain distance, i.e., after the overburden has collapsed and stabilized, the densely packed individual hydraulic props within the stabilized overburden area are retrieved. After retrieval, the individual hydraulic props are promptly reinforced with timber supports. As the working face continues to advance, the individual hydraulic props are gradually retrieved.

[0061] Any parts not mentioned in this invention can be achieved by referring to existing technologies.

[0062] It should be noted that any equivalent or obvious modifications made by those skilled in the art under the guidance of this specification should be within the scope of protection of this invention.

Claims

1. A single roadway steeply inclined thick coal seam fully mechanized caving face roadway layout method, characterized in that, Comprise the following steps in sequence: S1, along the steep thick coal seam floor level to the rock roadway, forming a coal seam, three sides of the rock straight angle trapezoidal, while, in the roadway of the upper corner formed by the slot inward; S2, in the roadway of the roof of the metal mesh, the lower part of the metal mesh is provided with transverse I-beam, one end of the transverse I-beam is inserted into the slot, and the rock layer under the slot supports it; S3, the anchor rod is used to strengthen the support of the transverse I-beam; S4, continue to dig along the direction of the roadway section until the transportation up and down and the return air up and down, forming a ventilation system; S5, after the roadway is connected, the coal beside the roadway is mined at the transportation up and down, the mining height is the same as the height of the roadway, then the top coal caving hydraulic support is arranged to mine the top coal above the working face; S6, after the coal is mined, the coal in front of the top coal caving hydraulic support is mined, the mining height is the same as the height of the roadway; the adjacent top coal caving hydraulic supports are pushed forward by interaction, and then the top coal is continued to be caved; the roadway behind the working face is densely reinforced by single hydraulic support; S7, the steps S5 and S6 are recycled in sequence, the grouting pipe is arranged on the floor of the goaf after the working face advances a certain distance, the yellow mud slurry is injected into the floor of the goaf through the grouting pipe, and the yellow mud slurry covers the residual coal in the goaf; S8, when the working face advances a certain distance, that is, after the overburden rock collapses and stabilizes, the single hydraulic support in the overburden rock stable range is recycled, after the single hydraulic support is recycled, the wood support is supplemented in time, and with the continuous advancement of the working face, the single hydraulic support is gradually recycled.

2. The single roadway steeply inclined thick seam fully mechanized caving face roadway layout method according to claim 1, characterized in that: In step S3, the anchor rod is vertically anchored in the roof of the roadway, and the roadway side of the rock layer is also vertically supported by the anchor rod.

3. The single roadway steeply inclined thick seam fully mechanized caving face roadway layout method according to claim 1, characterized in that: In step S4, the single hydraulic support is used to support the transverse I-beam, the longitudinal I-beam parallel to the roadway is arranged above the single hydraulic support, the transverse I-beam is arranged above the longitudinal I-beam, and the other end of the transverse I-beam is supported by the longitudinal I-beam.

4. The single roadway steeply inclined thick seam fully mechanized caving face roadway layout method according to claim 1, characterized in that: The grouting pipe is equally spaced with several roots.

5. The single roadway steeply inclined thick seam fully mechanized caving face roadway layout method according to claim 1, characterized in that: The top coal caving hydraulic support is provided with several parallel roots.

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