RU2278271C2 - Method and device for automatic mine tunnel degassing - Google Patents

Abstract

FIELD: mining, particularly fire and explosion protection means.

SUBSTANCE: device comprises mine fan and abnormal gas contamination control means, which includes control apparatus to control abnormal gas contamination in mine tunnel space, sensors to record lower explosive limit, cylinder with compressed air and compressed air flow regulator, which is connected to the cylinder to control air flow discharge therefrom. The sensors are connected with control apparatus by manifold and cable line. Lower explosive limit sensor output is attached to compressed air flow regulator inlet. Pneumatic compressed air flow regulator outlet is communicated with gas contaminated mine tunnel zone. Compressed air flow regulator, lower explosive limit sensor and compressed air cylinder may be arranged on mining machine body to provide emergency air discharge from the cylinder to cutting tool and mine face zone. Explosion-safe accumulative power source is additionally installed on mining machine body. Mine tunnel degassing method with the use of above device involves elimination of methane concentration in mine tunnel due to air flow velocity increase in mine tunnel along with lower gas mixture explosive limit control in gas contaminated zone of mine tunnel. If lower explosive limit is detected emergency compressed air discharge from compressed air cylinder is carried out to reduce gas content in mine tunnel.

EFFECT: increased degassing rate and reduced risk of methane explosion to be caused by igniter present in gassed zone.

3 cl, 1 dwg, 1 tbl

Description

The invention relates to the field of mining, as well as the chemical industry and can be used to prevent explosion and fire.

All cases of exceeding the norms of methane concentration in the cross section of a mine are referred to as polluted.

A device for degassing dead-end workings is known, comprising ([2] p. 161) a nozzle with a valve, a winch with a cable, a local ventilation fan, and a portable device for determining the concentration of methane.

A disadvantage of the known device is that the system is slow.

The closest in technical essence and the achieved result to the declared one is ([2] p. 158) with the combine method of working the workings, an ejector (fan) installed on the combine body, and air is supplied to the cutting organ in the bottomhole part of the development.

In the mine workings, the prevention and elimination of methane accumulation is carried out due to the general increase in the air speed from the mine shaft fan and the local (for combines) air flow redistribution in the lava working space with the help of additional draft sources (ejectors) of small-sized fans.

Among the disadvantages of the known device is the low speed determined by the clock.

The purpose of the invention is to increase the speed and, accordingly, to reduce the risk of methane explosion from an igniter located in the gasified zone.

This goal is achieved by the fact that in the device for the degassing of mines, including a shaft fan and a device for monitoring the emergency gas contamination of the space, the latter contains an apparatus for monitoring the emergency gas contamination of the space (1), sensors for fixing the lower explosive limit of the gas mixture (2) connected to the device for monitoring the emergency gas contamination spaces (1) with a trunk cable line (3), a can of compressed air (4) and a regulator for the release of compressed air (5) from the can connected to the can air, while the output from the sensor for fixing the lower explosive limit is connected to the input of the compressed air exhaust regulator (5), and the pneumatic output 5b of the regulator is directed to the gas-filled zone of generation. For emergency air supply from the cylinder to the cutting body and the bottom-end of the production, a sensor for fixing the lower explosive limit of the gas mixture (2), a cylinder of compressed air and a regulator for the release of compressed air (5) are installed on the combine body, while an explosion-proof battery power supply is also introduced, also mounted on the combine body.

Known methods of degassing: general and local (for sources of gas evolution) by increasing air velocity (§ 238 [1], p. 157, 158 [2]).

A general increase in air speed is carried out by the main ventilation fan, a local increase in speed - with the help of additional sources of traction (ejectors, small fans).

The disadvantage of this method should be considered low speed, i.e. the time from the moment a decision is made on the advisability of increasing the speed by a certain value until it is completed can be more than two hours.

As is known [3], with a sudden release of coal and gas, the concentration of methane in the faces and workings increases rapidly (Table 1) and an explosive methane-air mixture can form. And in order to avoid sources of ignition of the mixture and prevent a possible explosion, it is necessary to turn off all equipment in a timely manner and stop the technological processes.

Table 1 one. Initial volume fraction of methane before emission,% 0 0.5 1,0 2.0 2. Rise time of methane concentration from initial to lower explosive limit 0, after sudden release, s 2.84 2,36 2.0 1.14

The concentration of the mine atmosphere above the lower explosive limit also occurs in other cases, for example, in the event of a violation of normal ventilation (§ 244 p. 67 [1]).

As can be seen from the table, gas pollution can occur in 1.14-2.84 s, and it will take hours to gas out using an increase in air speed.

The farther the mine site is in a gassed state with explosive concentration, the greater the likelihood of an explosion from the igniter that appears on this site, the simpler technological equipment increases.

The purpose of the invention is to increase the speed of degassing of the production site.

This goal is achieved by the fact that in the method of degassing mine workings using the device described above, methane accumulations in the workings are eliminated due to a general increase in air velocity, the occurrence of the lower explosive limit of the gas mixture in the gasified production zone and the release of clean compressed air under pressure into the gasified zone production at the moment of fixing this explosive limit. This produces the degassing of the output.

The invention is illustrated in the drawing, which shows a structural diagram of an automatic device for the degassing of a mine.

An automatic mine degassing device includes a shaft fan (not shown), an emergency gas contamination control apparatus [4], a sensor 2 for fixing the lower explosive limit of the gas mixture, a trunk cable line 3 connecting the sensor 2 to the apparatus 1, a cylinder with compressed air 4, regulator 5 release of compressed air from the cylinder.

The operation of the circuit is as follows. When the lower explosive limit of gas appears for a given sensor 2, which controls the production area, sensor 2 fixes [4] this lower explosive limit. The local signal from the sensor 2 is fed to the input of the regulator 5. The regulator connects its pneumatic output 5V with a cylinder of compressed air 4.

Under the action of pressure, compressed air from the cylinder is directed to the gasified production zone. If from a cylinder 4 with a capacity of O pressure P release all gas into the production atmosphere, then it would occupy a volume of P times the volume O of the cylinder.

The volume q that will take the gas leaving the cylinder is

q = O · R m ³ .

The indicated volume will occupy a working section S of length L. Moreover, the working length is

L = O · P / S.

For example:

at D = 2 m ^h, P = 150W, S = 10 m ² L = 2 · 150/10 = 30 m.

When the concentration becomes lower than the lower explosive limit, the sensor 2 will give a signal to the control unit 1 through the trunk cable line 3. From the device 1, the signal is transmitted to the dispatcher that there is no explosive gas concentration in the production area controlled by this sensor 2. After a reduction in methane concentration to 1% in accordance with § 238 [2], the operation of the combine is allowed to resume.

Literature

1. Safety regulations in coal mines, Moscow, 1995.

2. Safety regulations in coal mines (Instructions), Moscow, 1966

3. Z.P. Kolosyuk Doctor of Engineering, V.P. Koptikov Ph.D., V.S. Zamzhitsky engineer (MakNII). The time of power outages and electrical equipment and mining machines. Occupational and industrial safety. 92-4 Subsoil. 1992

4. Patent for invention No. 2124745, class G 01 W 1/00, 01/10/1999.

Claims (3)

1. The device for automatic degassing of mine workings, including a shaft fan and a device for monitoring the emergency gas contamination of the space, characterized in that to increase the speed of gas degassing of the mine workings, the device for monitoring the emergency gas contamination contains an apparatus for monitoring the emergency gas contamination of the space, sensors for fixing the lower explosive limit of the gas mixture, connected with an apparatus for monitoring the emergency gas contamination of the space by a trunk cable line, b allon with compressed air and a regulator for the release of compressed air from the cylinder, connected to the cylinder with compressed air, while the output from the sensor for fixing the lower explosive limit of the gas mixture is connected to the input of the regulator for the release of compressed air from the cylinder, and the pneumatic output of the regulator for the release of compressed air from the cylinder is directed into the gasified production zone. 2. The device according to claim 2, characterized in that the sensor for fixing the lower explosive limit of the gas mixture, the cylinder with compressed air and the regulator for the release of compressed air from the cylinder are installed on the processor’s body and an explosion-proof battery pack is also introduced, which is also installed on the processor’s body. 3. The method of automatically degassing mine workings using the device according to claim 1, including eliminating the accumulation of methane in the workings due to a general increase in the air velocity in the workings, controlling the appearance of the lower explosive limit of the gas mixture in the gassed zone of the mine, and letting clean compressed air into the gassed production zone at the moment of fixing this explosive limit.