CN218454763U - Outburst prevention structure for rock-lift gate of near-coal-seam shaft construction group - Google Patents

Abstract

The utility model belongs to the technical field of coal mining crowd takes off the stone door and prevents suddenly, faces a plurality of stone doors of nearly coal seam crowd and reveals the problem when having solved the shaft construction of many coal seam development district high gas mine or coal and gas outburst mine, probably leads to the problem that stress concentration release and gas gush out the transfinite suddenly between the coal seam crowd. The utility model provides a nearly coal seam shaft construction crowd takes off rock-cut door and prevents abrupt structure is provided, including the shaft with be located the regional structure of taking out in advance of shaft place, take out the structure in advance and include a plurality of purpose layers of treating the extraction, be used for assisting the purpose layer to creep into and the straight wellsection of fracturing and make oblique section, be used for communicating the purpose layer and carry out the coal bed gas of taking out in advance of taking out to the purpose layer. By carrying out fracturing pre-pumping in the whole area on coal beds around the vertical shaft, the problems of interlayer stress superposition possibly caused by uncovering a stone door by a plurality of adjacent high-gas high-pressure coal beds and excavation surface stress concentration or gas overrun caused by mass gas emission and even coal and gas outburst accidents caused by the coal and gas outburst can be effectively solved.

Description

Outburst prevention structure for rock-lift gate of near-coal-seam shaft construction group

Technical Field

The utility model belongs to the technical field of coal mining crowd takes off the stone door and prevents suddenly, concretely relates to nearly coal seam shaft construction crowd takes off stone door and prevents suddenly structure.

Background

After coal mining for many years, the high-quality coal resources which are shallow and deeply buried near the surface of the earth are deficient, coal mining in partial areas is carried out by transferring to deeper underground, the gas content of a coal seam is gradually increased, and the partial areas face the problem of mining near coal seam groups under complex geological conditions.

The problems of stress concentration release among coal seam groups and sudden gas emission overrun can be caused by the problem that multiple stone gates of a near coal seam group are exposed during the construction of a coal mine vertical shaft, and the stress of a surrounding coal reservoir and the adjacent coal seam group and the gas threat are caused when a shaft bottom yard is arranged near the near coal seam group at the bottom of the vertical shaft.

Disclosure of Invention

The utility model discloses a solve above-mentioned at least one technical problem who exists among the prior art, provide a nearly coal seam shaft construction crowd takes off stone door and prevents abrupt structure.

The utility model discloses a following technical scheme realizes: the utility model provides a nearly coal seam shaft construction crowd takes off rock-cut door and prevents abrupt structure, includes the shaft and is located the regional structure of taking out in advance of shaft place, takes out the structure in advance and includes a plurality of purpose layers of treating the extraction, is used for assisting the straight well section and the oblique section of purpose layer drilling and fracturing, is used for communicateing the purpose layer and carries out the coal bed gas of taking out in advance of taking out to the purpose layer.

Preferably, the target layer corresponds to the deflecting sections one by one, the connecting point of the straight well section and each deflecting section is a deflecting point, the deflecting points are sequentially arranged along the height direction of the straight well section, the connecting point of the target layer and the corresponding deflecting section is a landing point, and the terminal point of the target layer along the drilling direction is a target point; and performing horizontal staged fracturing on the drilled target layer through a fracturing pipe column, and plugging the target layer through a plugging device.

Preferably, the bottom end of the coal bed gas pre-pumping well is positioned below the bottom plate of the lowest target stratum, and the coal bed gas pre-pumping well is communicated with the target stratum through the perforation.

Preferably, the shaft is located between the landing point and the target point of the target layer, a shaft detection platform is arranged at the position, located above the uppermost target layer, of the shaft, a coal field geological borehole used for coring the target layer and testing gas content parameters is arranged downwards from the shaft detection platform, and the bottom end of the coal field geological borehole drills into the lowermost target layer.

Preferably, the stopper is located in the deflecting section 10m below the deflecting point, and the bottom end of the coal bed gas pre-pumping well is located 30m below the bottom plate of the target layer below.

Compared with the prior art, the beneficial effects of the utility model are that:

1. this structure is through carrying out the fracturing of whole region to coal seam around the shaft and taking out in advance, can solve effectively when the shaft construction because the stack of interlaminar stress that a plurality of neighbouring high gas high pressure coal seams uncovered the stone door probably leads to and the excavation face stress concentration or the gas transfinite that the gas gushes out in a large number and cause, even induce the problem that coal and gas outburst accident take place.

2. The structure provides data reference for shaft exploitation through the coal field geological drilling detection and treatment effect in the later shaft exploitation process, and can improve the shaft construction safety.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is an overall structural schematic diagram of the present embodiment.

In the figure: 1-a vertical shaft; 2.1-destination layer; 2.2-straight well section; 2.3-deflecting section; 2.4-pre-pumping the coal bed gas; 3-a wellbore exploration platform; 4-geological drilling of coal field.

Detailed Description

The technical solutions in the embodiments of the present invention will be apparent from and fully described in conjunction with the accompanying drawings in the embodiments of the present invention, and it is apparent that 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 a person of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

It should be understood that the structures, ratios, sizes, and the like shown in the drawings and described in the specification are only used for matching with the disclosure of the specification, so as to be understood and read by those skilled in the art, and are not used to limit the practical limitations of the present invention, so they have no technical essence, and any modifications of the structures, ratios, or sizes should still fall within the scope of the present invention, which can be covered by the technical disclosure, without affecting the efficacy and the achievable purpose of the present invention.

The utility model provides an embodiment:

as shown in fig. 1, the burst-preventing structure for the near-coal-bed vertical well construction group rock-uncovering door comprises a vertical well 1 and a pre-extraction structure located in the region of the vertical well 1, wherein the pre-extraction structure comprises a plurality of target layers 2.1 to be extracted, a straight well section 2.2 and a deflecting section 2.3 for assisting drilling and fracturing of the target layers 2.1, and a coal-bed gas pre-extraction well 2.4 for communicating the target layers 2.1 and pre-extracting the target layers 2.1.

The target layer 2.1 corresponds to the deflecting sections 2.3 one by one, the upper ends of the straight well sections 2.2 are positioned on the ground, the connecting points of the straight well sections 2.2 and each deflecting section 2.3 are deflecting points, the deflecting points are sequentially arranged along the height direction of the straight well sections 2.2, the connecting points of the target layer 2.1 and the corresponding deflecting sections 2.3 are landing points, and the end point of the target layer 2.1 along the drilling direction is a target point; and performing horizontal staged fracturing on the drilled target layer 2.1 through a fracturing pipe column, plugging the target layer 2.1 through a plugging device on the fractured target layer 2.1, wherein the position of the plugging device is positioned in a deflecting section 10m below each deflecting point.

The bottom end of the coal bed gas pre-pumping well 2.4 is located 30m below a bottom plate of the lowest target layer 2.1, then a perforating gun is put into the coal bed gas pre-pumping well to respectively perforate all the target layers 2.1, the coal bed gas pre-pumping well 2.4 is communicated with the target layers 2.1 through perforation, drainage and pressure reduction are carried out to drain and recover the coal bed gas, meanwhile, the integral pre-pumping of the multi-target layers in the longitudinal direction is achieved, gas in a coal bed group at the position of a vertical shaft 1 is quickly reduced, and the risk of cross-cut coal uncovering is reduced.

The vertical shaft 1 and the coalbed methane pre-pumping well 2.4 are both positioned between a landing point and a target point of a target layer 2.1, a shaft detection platform 3 is arranged at a position above the uppermost target layer 2.1 of the vertical shaft 1, a coal field geological borehole 4 used for coring the target layer and testing gas content parameters is downwards arranged from the shaft detection platform 3, and the bottom end of the coal field geological borehole 4 is drilled into the lowermost target layer 2.1.

The specific construction process comprises the following steps: (taking four destination layers as an example, a first destination layer, a second destination layer, a third destination layer and a fourth destination layer from top to bottom)

1. According to the position of a shaft of a coal mine shaft 1 and the depth of a target layer 2.1, a well mouth in a straight well section 2.2 drilling process is subjected to blowout prevention measures, the drilling adopts a large-diameter three-opening well body structure design, slurry replacement treatment is carried out on a full well hole close to a deflecting point, degradable drilling fluid is replaced, then deflecting point deflecting is designed according to the position of a local coal reservoir layer, landing is carried out after the drilling is carried out to a first target layer, the drilling is stopped at a target point of the first target layer, casing pipe running is carried out to carry out full well cementing of the first target layer and the three-opening well, cementing slurry is solidified and then is put into a fracturing pipe column to carry out hydraulic sand adding fracturing on the first target layer, and plugging is carried out on the first target layer after fracturing.

2. Utilizing a guider to enable a drill bit to vertically drill downwards to a second deflection point to start deflecting according to design, drilling to a second target layer to land, then drilling to a target point of the second target layer, stopping drilling and running a casing, cementing the whole section from a windowing position to the second target layer, after the cementing slurry is solidified, running a fracturing pipe column to perform hydraulic sand fracturing on the second target layer, and after fracturing of the second target layer is completed, plugging a plugging device on the second target layer; the same method is adopted for the third and fourth target coal seams.

3. After all fracturing is finished, a tool string for taking the plugging device is put into the ground, the plugging device reserved in each target layer 2.1 is unsealed in sequence, and the shaft is lifted out; and after the whole reservoir fracturing is finished, constructing a coal bed gas pre-pumping well 2.4 at the shaft of the coal mine shaft 1, respectively perforating at each target layer, and then performing multi-target layer integral drainage and pressure reduction to extract the coal bed gas.

4. In the later construction process of the coal mine shaft 1, the shaft is firstly excavated downwards to the shaft detection platform 3 (the distance exposes 50-60 m from the first target layer bottom plate), and the coal bed geological drilling 4 is downwards adopted to drill to test the pressure and the coring of each coal bed so as to test the content of coal bed gas, so that the safety in the process of uncovering each interlayer rock cross-cut is ensured, and the gas outburst danger of the uncovering rock cross-cut is thoroughly eliminated.

5. And continuing to construct the shaft of the vertical shaft 1 downwards until the construction of the vertical shaft is finished.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (5)

1. The utility model provides a nearly coal seam shaft construction crowd takes off rock-cut door and prevents suddenly structure which characterized in that: the well comprises a vertical shaft (1) and a pre-pumping structure located in the region of the vertical shaft (1), wherein the pre-pumping structure comprises a plurality of target layers (2.1) to be pumped, a vertical shaft section (2.2) and a deflecting section (2.3) for assisting the drilling and fracturing of the target layers (2.1), and a coal bed gas pre-pumping well (2.4) for communicating the target layers (2.1) and pre-pumping the target layers (2.1).

2. The near-coal seam shaft construction group rock uncovering door outburst prevention structure of claim 1, which is characterized in that: the target layer (2.1) and the deflecting sections (2.3) are in one-to-one correspondence, the connecting points of the straight well sections (2.2) and each deflecting section (2.3) are deflecting points, the deflecting points are sequentially arranged along the height direction of the straight well sections (2.2), the connecting points of the target layer (2.1) and the corresponding deflecting sections (2.3) are landing points, and the end point of the target layer (2.1) along the drilling direction is a target point; and the drilled target layer (2.1) is subjected to horizontal staged fracturing through a fracturing pipe column, and the fractured target layer (2.1) is plugged by a plugging device.

3. The near-coal seam shaft construction group rock uncovering door outburst prevention structure of claim 2, wherein: the bottom end of the coal bed gas pre-pumping well (2.4) is positioned below the bottom plate of the target layer (2.1) at the lowest part, and the coal bed gas pre-pumping well (2.4) is communicated with the target layer (2.1) through perforation.

4. The near-coal seam shaft construction group rock uncovering door outburst prevention structure of claim 2, wherein: the shaft (1) is located between the landing point and the target point of a target layer (2.1), a shaft detection platform (3) is arranged at the position, located above the uppermost target layer (2.1), of the shaft (1), a coal field geological drilling hole (4) used for coring the target layer and testing gas content parameters is downwards arranged from the shaft detection platform (3), and the bottom end of the coal field geological drilling hole (4) is drilled into the lowermost target layer (2.1).

5. The near-coal seam shaft construction group rock uncovering door outburst prevention structure of claim 3, wherein: the plugging device is positioned in a deflecting section (2.3) which is 10m below a deflecting point, and the bottom end of the coalbed methane pre-pumping well (2.4) is positioned 30m below the bottom plate of a target layer (2.1) below the bottom plate.

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