RU2310073C1 - Safe mine for gas-bearing fire-hazardous seam cutting - Google Patents

Abstract

FIELD: coal industry, particularly to design and develop coal mines for gas-bearing fire-hazardous seam cutting.

SUBSTANCE: mining operations are simultaneously carried out in three extraction pillars cut along the strike and extending from central three-sectional inclined bore adapted to convey fresh air to three inclined flank bores isolated one from another. The inclined bores are adapted to separately remove jet coming from cutting operations, second workings and methane-and-air mix from goaf. Intermediate drift and two-sectional drift are excavated in upper extraction pillars so that intermediate drift is in flank bore. The two-sectional drift is provided with partition, perforated openings and filling concrete wall. Degassing operations are carried out in central extraction pillar to preliminarily discharge methane from coal bed and rock massif with drilling rig and degassing vacuum pump location in previously drilled two-sectional drift with independent ventilation. Second workings are performed in low pillar without coal column establishment with the use of high-productive mechanized complex having 200-300 m length. Fresh air passes from central three-sectional inclined bore simultaneously via belt drift, intermediate drift and two-sectional vent drift. Outlet air jet containing not more than 1% of methane is discharged via intermediate drift and then moves to surface via isolated flank inclined bore. Installed on the surface is sucking fan with variable output, which provides controllable removal of methane-air mixture from mine. The methane-air mix is then mixed with degasification methane in gas piston electric plant for electric power generation.

EFFECT: increased operational safety.

1 dwg

Description

The invention relates to the coal industry and can be used in the design and operation of coal mines, practicing gas-bearing, fire hazardous seams.

A coal mine is known for working out fire-hazardous, gas-bearing coal seams, including opening a mine field with three central and three flank sloping openings, mining mining pits with long working faces along the strike in ascending order and direct-flow ventilation using perforated coal pillar between the mining posts / G.M. Zolotarev “Technological scheme of working out fire-hazardous gas-bearing coal seams”, “Coal” magazine, No. 12, 1997 /.

The disadvantage of this coal mine is the difficulty in organizing the preliminary degassing of the coal seam due to the impossibility of placing degassing drilling rigs and a vacuum gauge suction pipeline in the cramped openings that transport coal, the difficulty in organizing the ventilation of the openings simultaneously with the ventilation of the working faces, the presence of coal pillars subject to crushing in worked out space.

A coal mine is also known, including the mining of excavation columns with high-performance long working faces along the strike of the bed with guarding of conveyor and ventilation drifts by coal pillars with the passage of inter-track faults every 30 m / A. Korovkin et al. “Theory and practice of long-wave systems”, LLC Techgormash. M., 2004, with 492-495 /.

The disadvantage of such a coal mine is the presence of a coal pillar, which creates the danger of a fire when it is crushed in the worked out space. In addition, during the return ventilation of the working face, the workers and electrical equipment are located in the workings along which the outgoing dusty, gas-polluted air stream is discharged, which under certain conditions can cause a methane explosion.

The aim of the present invention is to provide a safe coal mine for the development of gas-bearing, fire hazardous seams.

This goal is achieved due to the fact that mining is carried out simultaneously in three excavation columns, cut along the strike of the formation from the central inclined shafts, along which a fresh stream of air flows, to three flank shafts isolated from each other, along which the outgoing stream of air is discharged. Central inclined shafts pass in the form of a three-section inclined working out, the sections of which are separated by a concrete strip from the hardening filling mixture. Flank inclined trunks are isolated from each other by coal pillars.

Excavation work is underway in the upper excavation column, based on ventilation, transporting coal, materials and equipment to the flank shaft closest to the center. At the same time, an intermediate drift and a two-section ventilation drift with a dividing, perforated openings, concrete filling wall pass.

In the middle extraction column, degassing operations are underway for preliminary methane extraction from the coal seam and rock mass with the placement of drilling rigs and a degassing vacuum pipeline on a previously completed two-section drift with separate ventilation.

In the lower extraction column, cleaning operations are underway without leaving a coal pillar using a high-performance mechanized complex 200-300 m long.

Coal is transported from the face by a conveyor drift, formed by the reuse of the upper section of the ventilation drift, guarded by a concrete filling wall with additional fastening in the bottom-hole part of the conveyor drift by portable hydraulic stands.

Transportation of materials and equipment is carried out along the lower section of the ventilation drift to the zone of the working face.

Ventilation of the working face is carried out by supplying fresh air through the conveyor drift, the intermediate drift, and a two-section ventilation drift.

An outlet jet with a methane content of not more than 1% is diverted along the overlying intermediate drift and then along the isolated middle flank inclined shaft to the surface.

The methane-air mixture is removed from the worked-out space through openings in the filling wall along the upper section of the ventilation drift, which is kept behind the working face, and then along the extreme isolated flank barrel to the surface, where a variable capacity suction fan is installed, which provides controlled extraction of the methane-air mixture from the mine using it in the mixture with degassing methane in gas reciprocating power plants to generate electricity.

An example implementation of the proposed safe coal mine for the development of gas-bearing fire hazardous seams is shown in the drawing.

A safe coal mine with a production capacity of 4.0 million tons / year includes a two-winged mine field, in which coal is mined from one seam. A two-winged mine field is opened by a central three-section inclined shaft 1 and two groups of flank inclined shafts 2. In the mine field, mining operations are simultaneously carried out in three extraction columns.

Excavation works are carried out in the upper extraction column 3, based on ventilation, transporting coal, materials and equipment to the flank barrel 2, which is closest to the center. At the same time, an intermediate drift 4 and a two-section ventilation drift 5 are made with a dividing, perforated apertures, concrete filling wall 6.

In the average extraction column 7 are degassing. Drilling rigs are installed on the lower section of the ventilation drift 5 and a degassing vacuum pipe is laid for the extraction of methane from the coal seam at least 6 months before the start of coal extraction in the working face.

In the lower extraction column 8, they carry out cleaning operations without leaving a coal pillar using a high-performance mechanized complex 200-300 m long.

Coal is transported from the face 9 through a conveyor drift 10, which is formed due to the reuse of the upper section of the ventilation drift 5. The conveyor drift is guarded by a concrete filling wall 6. Additionally, portable hydraulic stands are installed in the bottom-hole part of the conveyor drift.

The transport of materials and equipment in the working face is carried out along the lower section of the ventilation drift 5.

Aeration of the working face is carried out by supplying fresh air through the conveyor drift 10, on the overlying intermediate drift 4, on a two-section ventilation drift 5.

An outlet jet with a methane content of not more than 1% is diverted along the overlying intermediate drift 4 and then along the isolated middle flank inclined shaft 2 to the surface.

The methane-air mixture is withdrawn from the worked-out space through openings in the filling wall along the upper section of the ventilation drift 5, which is kept behind the working face, and then along the extreme isolated flank barrel to the surface, where a variable capacity suction fan 11 is installed, which ensures controlled methane-air mixture suction from the mine using it together with degassing methane in a gas piston power plant 12 to generate electricity.

The specified scheme of a safe coal mine provides comfortable working conditions for miners, since they are constantly on a fresh stream of air, safety against methane explosions, and safety due to the factor of the occurrence of endogenous fires.

Due to the preliminary degassing of the coal seam, the amount of fresh air required for ventilating the working face is reduced and the safety factor “ventilation of the working face” is increased.

Due to the degassing of the worked-out space during the sudden landing of the hard-to-collapse main roof, the methane-air mixture does not instantly squeeze out of the worked-out space into the bottomhole zone and, accordingly, there is no dangerous situation with the possible explosion of methane due to instant compression and the occurrence of a shock wave.

Due to the absence of coal pillars in the worked out space, the risk of a fire hazard due to crushing of pillars of coal is reduced.

Literature

1. Zolotarev G.M. Technological scheme of working out fire-hazardous gas-bearing coal seams, Ugol magazine, No. 12, 1997, p.16.

2. Korovkin Yu.A. and others. Theory and practice of long-lobe systems. M., From LLC Techgormash, 2004, from 492-495.

Claims (1)

Safe coal mine for working out gas-bearing fire hazardous seams, including opening the mine field with central and flank inclined shafts, preparing excavation columns with contouring drifts, mining excavation columns along the strike of the formation with long treatment faces using high-performance mechanized complexes, characterized in that mining operations are carried out simultaneously in three mining operations excavation columns, cut along the strike of the formation from the central three-section slope, along which air stream, up to three flank slopes isolated from each other, along which the outgoing stream is separately diverted from tunneling operations, from cleaning operations and the methane-air mixture from the worked out space, and in the upper extraction column, penetration is carried out based on the flank slope of the intermediate drift and two-section drift with dividing, perforated openings, concrete filling wall; degassing works are being carried out in the middle extraction column for preliminary suction of methane from a coal seam and rock mass with the placement of drilling rigs and a degassing vacuum pipeline on a previously completed two-section drift with separate ventilation; cleaning works are carried out in the lower extraction column without leaving a coal pillar using a high-performance mechanized complex 200-300 m long, with fresh air coming from the central three-section inclined shaft at the same time via a conveyor drift, an intermediate drift, a two-section ventilation drift, and an outgoing air stream containing methane no more than 1% is diverted along the overlying intermediate drift and further along the isolated flank inclined shaft to the surface, in addition, from of the worked-out space, through the openings in the filling wall, the methane-air mixture is sucked onto the upper section of the ventilation drift isolated from people’s visits and then along the insulated flank inclined shaft to the surface, where a variable capacity suction fan is installed, which provides controlled extraction of the methane-air mixture from the mine using it in a mixture with degassing methane in gas piston power plants to generate electricity.