SU1712625A1 - Method of breakage face ventilation - Google Patents

Abstract

The invention relates to mining and m. used in mining coal gas fields for airing longwalls. The purpose of the invention is to increase the safety of work and the efficiency of ventilation of the clearing face by reducing the outflow of the gas-air mixture from the produced into the bottom hole. For this, the dead end of the vented air drift is filled with an inflatable tank of elastic airtight material, which is moved after the advancement of the clearing face. Fresh air enters the bottomhole space via a conveyor drift, and contaminated air is removed through a vented air drift. 3 ill. ^ The invention relates to mining and can be used in the mining of coal-bearing coal fields for airing long stoves. A method of aerating long stoves is known, according to which a fresh stream of air comes from a haulage and a single stream, washer) cleaning the bottomhole and the open space of the lava adjacent to it passes through the entire length of the lava and goes to the ventilation drift. The disadvantage of this method of airing the clearing faces in gas mines is the formation high concentrations of methane in the upper part of the lava and in the redeemable part (dead end) of the ventilation drift on the junction with lava. Pulsed removal of methane from the drainage drift. However, the known method is characterized by low efficiency and insufficient safety of airing of cleaning faces. In addition, it is necessary to conduct a drainage drift and fittings, the maintenance of which is associated with high material costs. It is impossible to control the concentration of methane in the drainage drift and to precisely regulate the flow of the gas-air mixture in it. The purpose of the invention is to increase the safety of work and the efficiency of airing longwalls. The goal is achieved. that according to the method of airing longwalls, including the supply of light and a

Description

A jet of air to the bottom and removal of polluted air through the ventilation drift to reduce the gaps of the gas-air mixture from the exhaust to the bottom hole, the dead end of the vented ventilation drift is filled with an inflatable tank, which is moved after the cleaning hole moves.

Fig. 1 shows the pattern of ventilation of the clearing hole and the zone of formation of local accumulation of methane and bullets of the gas-air mixture coming from the clearing hole developed into the bottom-hole space and into the dead end of the vented ventilation drift; in fig. 2 - the path of movement of the gas-air mixture from the exhaust to the bottom hole after filling the dead end of the reinstated ventilation drift with an inflatable container made of elastic material under excessive pressure, periodically moved after the cleaning face; in fig. 3 - distribution of methane concentration at the interface of the lava with the ventilation drift before (a) and after (b) filling the dead end of the vented ventilation drift with an inflatable tank.

The pattern of airing the clearing face is as follows.

Fresh air through the conveyor drift 1 (Fig. 1) enters the bottomhole space 2 and the developed space 3 adjacent thereto and is discharged through the ventilation drift 4. At the same time, the gas-air mixture with a high concentration of methane enters the deadlock of the vented ventilation drift 5. Since the air velocity vectors are directed in the opposite direction from the deadlock, the deadlock is not aired and a stagnant zone with a high concentration of methane forms here. Such accumulations of methane are not eliminated by simply increasing the flow rate of air supplied for airing the cleansing face.

The proposed method of airing the clearing of the slaughter is carried out as follows.

Fresh air through the conveyor drift 1 (Fig. 2) enters the bottomhole space 2 and the open space of the lava 3 adjacent to it and is discharged through the ventilation drift 4. The dead end of the vented ventilation drift 5 is filled with an inflatable tank 6 of elastic air-tight material under excessive pressure . The inflatable bag periodically moves following the advancement of the clearing face. At the same time, the dead zone at the interface of the clearing intake with the ventilation drift (dead end of redeemable ventilation drift) with increased methane concentration is eliminated, the way of filtration of the air flow from the depleted lava space is shortened by the amount of inflatable capacity (dead end width) and the flow of air-gas mixture from developed into the bottomhole lava space.

0 The gas-air mixture with a high concentration of methane from the mined-out space into the bottom-hole space of the clearing face 2 comes from the lower side (along the direction of the air jets) inflatable

5, into the zone of action of the active air jet passing through the bottomhole space and is diluted with this jet to acceptable standards.

Example. Formation process

0 of the gas situation at the interface of the clearing inlet with the ventilation drift before and after filling the dead end of the vented ventilation drift with an inflatable tank. Lava 32. KZ-In mine them. Kostenko is developing the Kz layer. Removable reservoir capacity TV 3 m; clearing speed of the VOM 3 m / day. Gas content of the excavation area 11 m / min; gaseous emission share

0 0.40. The length of the lava is 100 m; the width of the conveyor and ventilation drifts is 4 m each. The flow rate of the air supplied to ventilate the lava is 1200 m / min. It is necessary to determine the flow rate of the gas-air mixture

5 coming from the mined-out space, the concentration of methane in it and the flow of air passing through the bottom hole of the lava;

- in the middle of the dead end of the ventilation 0 drift;

- at the bottom wall of the inflatable tank, whose width is equal to the width of the ventilation drift.

The concentration of methane in the gas-air 5 mixture coming from the goaf, is determined by the formula

 b x 100

%

, 108 tv vo4

c, IUU IIIB RF AMP -J-G1 -hO, 12mB-Vo4 (1-x)

(one)

where First - gas content of the excavation site, First 11,

b is the fraction of the gas released from the worked-out space in the gas balance of the site, the share of the unit, b 0.40;

n is the intensity of the flow of methane from the goaf, determined by the formula

P 34B 34-0,4 5.44,

(2)

where SWV is the reservoir power taken out, Schw 3m;

UAC - speed of the movement of the clearing block, Vo4 3 m / day;

Qfl is the flow rate of air supplied to ventilate lava, Ol, 1200 m / min;

X is the ratio of the current coordinate in lava (1 |, m) to the total length of lava (| l, m) and the width of the conveyor and ventilation drifts, dol units.

In formula (1), the numerator is the amount of gas coming from the goaf, and the denominator is the flow of air in the goaf.

Air flow in the wellbore space is determined by the formula

Qn Ol (1 - Vx (l-x) X

0.108 Shv UOC

 1 + 0.12 Swiss V04 I

The concentration of methane in the gas-air mixture coming from the goaf to the dead end of the vented air inlet in the middle part of it is

5.44

11 -0.4 -0.98

0.467 1200 V 0.980-0.98) 5.0%.

Since the air passing through the borehole space does not reach the dead end of the redeemable vent, at the junction of the clearing hole with the air vent (at the dead end of the recharge ventilator) local accumulations of methane with an explosive concentration of 5% or more are formed.

The concentration of methane in the gas-air mixture coming from the inflatable space developed into the bottom hole at the lower edge of the inflatable tank is

11 -0.4 0,

0.467 1200VOi96 (1-0.96)

 3.2%.

The amount of gas coming from the produced into the bottomhole space is

1v.p. 110.4-0, 3.52.

The amount of gas flowing through the bottomhole face of the lava at the lower edge of the inflatable tank is

1p.p. 11 -3.52 7.48.

The flow rate of air passing through the invoice space of the lava at the level of the lower edge is

Qn 1200 (1 - VO, 96 (1-0.96) 0.467) 1090m / min.

The concentration of methane in the air passing through the upper part of the cleaning bottom of an inflatable tank is

 (7.48-3,5, 3.52) ..Qo-Qono / 1090 + 110 ° Thus, the calculations show that after the deadlock is filled, the ventilation duct with an inflatable tank in the face will be created in the normal gas mode.

The use of the proposed method of ventilation of gas-rich coal lavas provides the following advantages in comparison with existing methods: it allows eliminating the conditions for the formation of local accumulations of methane E by clearing a face; reduces the length of the filtration flow from the developed space and, therefore, reduces the inflow of the gas-air mixture from the developed into the bottom-hole space of the lava, increases the efficiency of the ventilation of the lava; improves safe working conditions

miners; creates conditions for increasing the load on the working face by reducing downtime of mining mechanisms during the formation of local accumulations of methane. In addition, the proposed method of airing longwalls is technological, does not require the penetration of additional workings, the construction of ventilation structures, the cost of its implementation is insignificant.

FORUMUA AND 3 ABOUT AND

The method of ventilation of the clearing intake, including the supply of fresh air jet to the bottom and removal of polluted air through the ventilation drift, is also distinguished by the fact that, in order to improve the safety of work and the efficiency of the ventilation of the clearing face, by reducing the outflow of the gas-air mixture from the exhaust gas the space, the dead end of the vented ventilation drift is filled with an inflatable tank, which is moved after the advancement of the clearing face.

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Claims (1)

Claim A method for ventilating a face, including supplying a fresh stream of air to the face and venting contaminated air through a ventilation drift, characterized in that, in order to increase the safety of work and the efficiency of venting a face, by reducing leakage of the gas-air mixture from the exhausted into the face, a dead end of the vented the drift is filled with an inflatable tank, which is moved after the movement of the working face. FIG. A method of ventilating long working faces 1-1 b) Tehred M. Morgenthal Proofreader M. Demchik