RU2732931C1 - Degassing method of working area - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention relates to mining, primarily to coal industry. Invention includes performance of working in a plane of the developed formation, leaving of coal pillars between working areas, drilling of a fan of wells along the adjacent taped formation, connection of wells to a vacuum system of a panel mine section and extraction of methane. Novelty of the invention consists in the fact that the wells of the adjacent formation are made from the bottom of the rock part of the well shaft, the mouth of which is located near the section working with the outgoing air flow, first of fan wells group is performed in parallel to ventilation with outgoing working jet, note here that methane-air mixes are withdrawn from adjoining worked-out space previously worked-out section through previously drilled well in developed formation top of well above interlava pillar of coal. Positive effect is achieved by using technological solutions for rational arrangement of wellheads of degassing wells intended for extracting methane from adjacent taped formation and extraction of methane-air mixtures from adjoining worked-out space through the rock well drilled in the top of the developed formation above the coal interlava pillar.

EFFECT: invention can be used in mines to reduce intensity of methane release into mine section working and maintenance of methane concentration allowable by safety rules at interface of mining face with section mine working.

1 cl, 4 dwg

Description

The invention relates to mining, mainly to the coal industry, and can be used in mines to reduce the intensity of methane emission in the workings of the excavation area and maintain the permissible PB concentration of methane at the interface of the working face with the section workings.

There is a known method of degassing sources of methane release at an excavation site, including carrying out workings in the plane of the mined seam, drilling wells in a coal seam, connecting wells to a vacuum system and extracting methane (Geotechnological problems of developing gas and dust hazardous coal seams [A.D. Ruban, G . S. Zaburdyaev, V. S. Zaburdyaev. IPKON RAS - Moscow: Nauka, 2007. - 279 p.; P. 15, 151-158].

The disadvantage of this method is that short (up to 200 m) wells are carried out in the extraction area, while the length of the extraction areas (fields) exceeds the length of such wells at times.

There is a known method of degassing coal seams, including fan drilling of long directional wells in the extraction area, connecting them to a vacuum system and extracting methane (Problems of ensuring high productivity of production faces in methane-rich mines [AD Ruban, VB Artemiev, V. S. Zaburdyaev et al. - M .: URAN IPKON RAN, 2009. - 396 pp. P. 218-223].

The disadvantages of this method include the lack of technological solutions for extracting methane from its main source - adjacent coal seams.

The closest in technical essence and the achieved result is the method of degassing the extraction area, including the development of workings in the plane of the mined seam, leaving coal pillars between the excavated sections, drilling in a fan of located wells along the adjacent undermined seam, connecting the wells to the vacuum system of the extraction field and extracting methane [Instruction for degassing coal mines. Series 05. Issue 22. - M .: ZAO STC for research of PB problems, 2012. - 250 p .; pp. 84-86, 121-124 (Prototype)].

The disadvantage of this method is that the layout and parameters of the location of wells drilled in a contiguous seam do not provide effective extraction of methane from a contiguous coal seam over its entire area and there is no possibility of extracting methane-air mixtures from a worked-out area adjacent to the existing one.

The technical objective of the invention is to improve the efficiency of degassing in the mined section of the formation and adjacent to it previously worked out due to the rational location of the wells in the extraction section.

This goal is achieved by the fact that in the section of the mine field, excavation areas are prepared with the inter-main pillars of coal left between them, a degassing-vacuum network is laid and wells of a directed route are carried out along a nearby undermined coal seam. The borehole, which is fundamental in the degassing scheme, is carried out from the seam working along the enclosing rocks to the undermined contiguous seam (or contiguous seams). A group of wells arranged in a fan-shaped manner along a contiguous formation is carried out from the rock part of the wellbore, the mouth of which is located near the section excavation with an air flow outgoing from the working face.

The essence of the invention is illustrated by drawings, where FIG. 1 and FIG. 2 shows the first of a group of fanned wells; in fig. 3 and FIG. 4 shows the schemes of borehole degassing of the extraction area.

The drawings show: mined coal seam - 1, working out with an outgoing air stream - 2, working out with a fresh air stream - 3, working face - 4, worked-out space of the existing section - 5, space of the previously worked out section - 6, working out of the next section - 7 , the line of unloading of the roof rocks - 8, the adjacent seam - 9, the pillar of coal between the sections - 10, the borehole along the rocks of the roof - 11, the borehole along the adjacent seam - 12, the well above the entire coal near the working with the outgoing air stream - 13, the well above whole coal near the worked-out area of the worked-out area - 14, the degassing pipeline - 15, the fresh air flow - 16, the exhaust air flow - 17, the development of the worked-out area - 18.

The method is implemented as follows.

The first of the group of wells arranged in a fan is carried out in parallel with the ventilation with the outgoing stream of the mine (Fig. 1, Fig. 2), while through the previously drilled in the roof of the mined seam a methane-air mixture is extracted from the adjacent mined-out space of the previously worked-out section (Fig. 1, fig. 3, fig. 4).

The first of the fan of wells is located in a contiguous layer, taking into account the angle of unloading of the roof rocks, set in accordance with the Instruction for degassing coal mines (2012). The rest of the wells in the adjacent coal seam are carried out with the possibility of the most complete coverage of it over the area (Fig. 1). The bottom holes of the first well in the fan and those closest to it are located so that they go beyond the line of the working development and are in the zone of the adjacent layer (or adjacent layers) unloaded from the rock pressure.

The number of boreholes in the development or in the crosscutting cutting of the extraction section of the developed formation is determined based on the possibility of the technique for drilling extended wells. The number of downhole degassing schemes of the production area shown in FIG. 1-4 are determined taking into account the length of the excavation area and the technical capabilities of the drilling equipment.

The wells drilled at the site are connected to the vacuum network of the extraction field, except for the well in the rock over the entire coal of the next extraction area.

Previously drilled wells in the roof of the mined seam above the entire coal inter-main are used to extract methane-air mixtures from the adjacent mined-out space to the active section. In this case, the well is carried out in the unloading zone of the coal pillar from the action of the development working outlining the extraction area, that is, the well is located closer to the edge of the left coal pillar 2-3 m from the sidewall of the working area of the coal seam (Fig. 4). Such a well is connected to a degassing pipeline and methane is captured, which accumulates in the roof of a previously worked out area.

The operations in accordance with FIG. 1-4 are implemented in the following sequence.

On the mine field within the limits of the planned excavation section along seam 1, delineating workings 2 and 3 are carried out, along working 3, fresh air enters the working face 4, and the outgoing air from the section is removed along working 2. The working face 4 is equipped with a miner for the destruction of the coal mass, control the roof is carried out by the complete collapse of underworked rocks 5 at the operating treatment site and rocks 6 at the previously worked out. Between workings 2 and 7, a pillar of coal 10 is left.

The zone of unloading rocks of the roof 8 and adjacent layer 9 is established according to the recommendations of the regulatory document.

The drilling rig is placed in a tunnel 2, from which the borehole 11 of the well is carried through the roof rocks to the adjacent layer 9, followed by drilling a fan of wells 12 in the plane of the adjacent layer 9 in the direction of the moving working face 4. The first of the fan well 12 is carried out in the plane of the adjacent layer 9 parallel to the working 2 outside the unloading zone 8 from the rock pressure of the seam 9. The closest to the parallel well 12 is carried out in the direction of the moving bottom 4 until the unloading of the adjacent seam 9 begins.

In the rocks of the roof of the mined seam over the entire coal 10, a well 13 is carried out in parallel with working 2, which is then used at number 14 to extract methane near the extinguished working 18 of the worked out space 6 of the previously worked area.

To ventilate the workings of the excavation section, fresh air 16 is supplied through the mine 3, passed it along the working face 4 and the exhaust air 17 is removed from the section along the mine 2.

Wells drilled in the plane of the adjacent layer 9 are connected to the degassing pipeline 15 and the captured methane is removed to the day surface. Well 14, drilled in the rocks of the roof of the mined seam over the entire coal, is connected to the degassing pipeline at the beginning of the development of the mined seam 1 on the existing section, contoured by workings 2 and 3.

The complex of the proposed technological solutions for degassing the mining area will increase the efficiency of degassing adjacent coal seams located in the roof of the mined seam and extract methane-air mixtures from the adjacent mined-out area of the previously mined area.

Claims (1)

A method of degassing a working area, including conducting workings in the plane of the working seam, leaving coal pillars between the working areas, drilling a fan of a directed line of wells towards the moving working face, connecting the wells to the vacuum system of the excavation field and extracting methane, which is different in that the wells along the contiguous layer, it is carried out from the rock part of the wellbore, the mouth of which is located near the section working with an outgoing air flow, the first of the group of wells located in a fan is carried out in parallel with the ventilation with the outgoing stream of the working, while through the previously drilled in the roof of the developed layer a rock well above the intermountain whole coal extract methane-air mixtures from the adjacent mined-out space of the previously worked-out area.

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