CN109899106B - A Gas Drainage Method in the Adjacent Layer of a Long-Turn Drilled Hole to Avoid the Caving Zone - Google Patents

Abstract

The invention discloses a gas extraction method for adjacent layers of long turning boreholes that avoids the caving zone. A long turning drilling surface is constructed on the side of the return air tunnel, and the caving zone is avoided according to the turning long drilling face, and the caving zone is not affected. Drilling into the stratum until the fissure zone, and can also drill a distance in the fissure zone, along the edge of the caving zone, drill a long extraction hole into the fissure zone of the coal seam roof in the goaf, and drill through the fissure zone of the coal seam roof. When venting gas in goafs and adjacent layers, self-steering drills are used to actively avoid the caving zone, and ordinary drilling is used, which reduces the technological process of roofing and drainage lanes, which can save more than 50% of manpower, material resources and financial resources. , which not only realizes the efficient extraction of gas from adjacent layers, but also effectively solves the problem of gas gushing at the corners of the working face. Provide effective technical support for surface safety production.

Description

A Gas Drainage Method in the Adjacent Layer of a Long-Turn Drilled Hole to Avoid the Caving Zone

technical field

The invention relates to the technical field of gas drainage in mining coal seams, in particular to a gas drainage method for adjacent layers of long-turned boreholes that avoids caving zones.

Background technique

At present, when the coal seam group is mined, the gas in other coal seams within a certain distance above and below the coal seam will also flow into the working face space of the mining coal seam along the cracks caused by the pressure relief. In order to relieve the adjacent seam surge In order to reduce the gas gushing to the mining layer due to the influence of mining, it is necessary to drill from the mining coal seam or the surrounding rock road to the adjacent coal seam, and drain the gas in the adjacent coal seam.

The commonly used adjacent layer gas drainage method is to first drill a separate gas drainage roadway, that is, the roof drainage roadway, drill holes from the roof drainage roadway into the crack zone, and drain the adjacent layer gas. The method is to carry out gas drainage from the boreholes or roadways arranged in the "annular fissure circle". It is necessary to drill a separate roof drainage roadway, and the roof gas of the coal seam is extracted through the roof drainage roadway or drilled through the roof drainage roadway. Or a pressure relief fracture along the bed tension crack is formed in the pressure relief coal seam, and a drill hole is drilled in advance from the pressure relief coal seam floor gas drainage roadway to the pressure relief coal seam in the pressure relief coal seam floor gas drainage roadway to the Internet. The pressure relief gas is collected to the drainage hole along the layered tension crack, and can be drained through the drainage pipeline; at the same time, the drainage hole is often collapsed due to the influence of the caving zone, and the drainage hole is reinforced by the lower casing. measure.

However, the above-mentioned gas drainage methods all require independent gas drainage tunnels on the roof or floor of the coal seam, reinforcement of drainage holes, and increase of the above-mentioned process links, which require a lot of money and consume a lot of manpower, material resources and financial resources. , How to overcome the above problems and put forward a novel method of mining adjacent layers of coal seam gas drainage, is the current need to solve.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the problems that the existing gas drainage methods all need to make independent gas drainage tunnels on the top or bottom of the coal seam, reinforce the drainage holes, increase the above-mentioned process links, and require a lot of money. The method of the invention for gas drainage in adjacent layers of a turning long borehole avoiding the caving zone can avoid the caving zone actively by means of the self-steering drill bit, and the ordinary drilling is adopted, which reduces the technical process link of the roofing plate drainage lane and saves money. It saves manpower, material and financial resources and realizes efficient gas extraction from adjacent layers, which has a good application prospect.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A method for gas drainage in adjacent layers of long-turned boreholes that avoids caving zones, comprising the following steps:

Step (A), according to the edge of the caving zone, construct a turning long drilling surface in the return air lane, the turning long drilling surface is set around the caving zone, and the distance between the bending long drilling surface and the caving zone is within 5-15m. between;

Step (B), drilling a number of drainage holes along the edge of the caving zone into the fissure zone of the coal seam roof of the mined-out area at regular intervals on the side of the return air roadway on the long turning borehole surface;

Step (C), avoid the caving zone area by selecting the position of the pilot bit, and continue drilling in the rock layer after the extraction hole accurately bypasses the caving zone;

Step (D), after the drill bit drills into the fracture zone, continue to drill for a certain distance to the fracture zone;

Step (E), seal holes, repeat steps (C)-step (D), complete step (B) to seal the holes of multiple extraction holes, until the turning and long holes that avoid the caving zone are sealed. hole;

Step (F), connect the main drainage pipeline with a rubber hose in each drainage hole, and pre-drain the gas before the working face is extracted;

In step (G), after the working face is mined, each drainage hole is connected to the fracture zone of the coal seam roof, and the gas in the goaf and adjacent layers is drained through the corresponding fracture zone.

In the aforementioned method for gas drainage in adjacent layers of the long-turned borehole avoiding the caving zone, in step (B), drill 1-1 to the fissure zone of the coal seam roof of the mined-out area along the edge of the caving zone every 30-50m in the return air tunnel. 3 extraction holes.

The above-mentioned method for gas drainage in adjacent layers of the long-turned borehole avoiding the caving zone, step (B), in the return air roadway every 30m along the edge of the caving zone to the coal seam roof fissure zone in the mined-out area to make a drainage drilling.

In the above-mentioned method for gas drainage of adjacent layers in a long turning hole avoiding the caving zone, in step (D), after the drill bit reaches the fissure zone, it continues to drill 120-200m into the fissure zone.

The above-mentioned method for gas drainage of adjacent layers in a turning long hole avoiding the caving zone, in step (D), after the drill bit reaches the fissure zone, it continues to drill 150m to the fissure zone.

In the aforementioned method for gas drainage of adjacent layers of long-turned boreholes to avoid caving belts, step (F), each drainage borehole is connected to the main drainage pipeline with armored rubber pipes.

The beneficial effects of the present invention are: in the method for gas drainage adjacent to the layer of the turning long borehole to avoid the caving zone, the opening point (surface) of the turning long borehole is constructed on the side of the return air roadway, and the turning long borehole is used (according to) The hole trajectory (surface) avoids the caving zone, and drills in the unaffected rock layer until the fissure zone, and can also drill in the fissure zone (a certain distance), along the edge of the caving zone to the gob Drilling a long drainage hole in the fissure zone of the coal seam roof, the drill hole drains the goaf and adjacent layer gas through the fissure zone of the coal seam roof, and the self-steering bit actively avoids the caving zone. It can save more than 50% of manpower, material resources and financial resources. It not only realizes efficient gas drainage of adjacent layers, but also can effectively solve the problem of working surface The corner gas gushing problem has a good application prospect in the treatment of the corner gas gushing problem on the high-yield and high-efficiency working face, and provides effective technical support for the safe production of the high-yield and high-efficiency working face.

Description of drawings

Fig. 1 is the flow chart of the gas drainage method for the adjacent layer of the long-turned borehole that avoids the caving zone of the present invention;

Fig. 2 is the structural representation of an embodiment of the turning long drilling surface of the present invention;

Fig. 3 is a schematic structural diagram of another embodiment of the turning long drilling surface of the present invention.

The meanings of the symbols in the accompanying drawings are as follows:

1: caving zone; 2: drilling; 3: fissure zone.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings.

As shown in FIG. 1 , the method for gas drainage in adjacent layers of a turning long borehole avoiding caving zone of the present invention includes the following steps:

In step (A), a long turning drilling surface is constructed in the return air lane according to the edge of the caving zone, the turning long drilling surface is set around the caving zone, and the long turning drilling surface is 5-15m away from the caving zone, such as 2 and 3 are shown. Two ways to turn the long drilling surface, among them, 1: caving zone; 2: drilling; 3: fissure zone;

Step (B), drill a number of drainage holes along the edge of the caving zone at intervals of a certain distance on the side of the return air roadway of the long turning borehole surface into the fracture zone of the coal seam roof in the goaf, and drill along the caving zone at intervals of 30-50m. Drill 1-3 drainage holes from the edge to the fissure zone of the coal seam roof of the goaf area. The number of drilling holes can be used to ensure the efficiency of gas drainage;

Step (C), avoid the caving zone area by selecting the position of the pilot bit, and continue to drill in the rock layer after the extraction hole bypasses the caving zone;

In step (D), after the drill bit reaches the fracture zone, continue to drill into the fracture zone for a distance of 120-200m, preferably 150m here;

Step (E), seal holes, repeat steps (C)-step (D), complete step (B) to seal the holes of multiple extraction holes, until the turning and long holes that avoid the caving zone are sealed. hole;

Step (F), connect the main drainage pipeline with a rubber hose in each drainage drilling hole, and pre-drain the gas before the working face is extracted. The rubber hose is an armored rubber hose, and the cost is low;

In step (G), after the working face is mined, each drainage hole is connected to the fracture zone of the coal seam roof, and the gas in the goaf and adjacent layers is drained through the corresponding fracture zone.

To sum up, the method of the present invention for gas extraction from the adjacent layer of the turning long borehole to avoid the caving zone, constructs the opening point (surface) of the turning long borehole on the side of the return air road, and uses (according to) the turning long borehole trajectory. (face) Avoid the caving zone, drill in the unaffected rock layer until the fissure zone, and can also drill in the fissure zone (a certain distance), along the edge of the caving zone to the gob coal seam roof Drilling long drainage holes in the fissure zone, through the fissure zone on the roof of the coal seam to drain the goaf and adjacent layers of gas, and actively avoid the caving zone through the self-steering drill bit. ), minus the technical process of rock roadway excavation in the top plate drainage roadway, which can save more than 50% of manpower, material resources and financial resources, not only realizes the efficient extraction of adjacent layers of gas, but also effectively solves the corners of the working face. The gas gushing problem has a good application prospect in the treatment of the gas gushing problem in the corner of the high-yield and efficient working face, and provides effective technical support for the safe production of the high-yield and efficient working face. The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (1)

1. A method for extracting gas in a turning long drill hole adjacent layer for avoiding a caving zone is characterized by comprising the following steps of: comprises the following steps of (a) carrying out,

step (A), constructing a turning long drilling surface in a return airway according to the edge of the caving zone, wherein the turning long drilling surface is arranged around the caving zone, and the distance between the turning long drilling surface and the caving zone is 5-15 m;

step (B), drilling 1 drainage drill hole into a coal seam roof fracture zone of the goaf at intervals of 30m along the edge of the caving zone on the side of the return airway of the turning long drill hole surface;

step (C), avoiding the area of the caving zone by selecting the position of the guide drill bit, and continuing drilling in the rock stratum after the drainage drill hole accurately bypasses the caving zone;

step (D), after the drill bit drills to the fractured zone, drilling for 150m to the fractured zone continuously;

step (E), sealing holes, namely repeating the step (C) to the step (D), and completing the sealing of the plurality of drainage drill holes in the step (B) until all drainage drill holes in the turning long drill holes in the caving zone are avoided;

step (F), connecting the armored rubber pipes to the drainage main pipelines by using the drainage drill holes, and pre-pumping the gas before the working face is not mined;

and (G) after the working face is mined, each drainage drill hole is communicated with a fracture zone of the coal seam roof, and gas in the goaf and the adjacent layer is drained through the corresponding fracture zone.

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