SU1548464A1 - Method of locating safe and hazardous zone in cyclic excavation of face-adjoining part of gas-bearing coal seam - Google Patents

Abstract

The invention relates to mining and can be used in the development of coal-bearing gas. The purpose of the invention is to improve the accuracy of determining the safe zones by taking into account the interrelation of the gas and stress state of the formation. In the clearing face, when excavating coal in 1 cycle, the acoustic emission level (AE) and gas emission (GW) from the bottom are simultaneously measured and the dimensions L (J) and L (X) of the safe discharge zone (BZR) are determined by AE and GV, respectively. Then drill holes, determine HBs from the holes and calculate the size of the BZR. The maximum difference σ between L (J) and L (X) in the first excavation cycle is determined. In subsequent cycles, the difference in the sizes of BZR in AE and HB is determined. If this difference is less than or equal to σ, then the size of the BZR is taken as the arithmetic average between the sizes of BZR in AE and GW from the bottom. If the difference is greater than σ, then in the area of the hole of the hole and the HB from the hole is determined and the dimensions of the unloading zone L are calculated from it. At / L - L (J) / * 98 σ / 2 and / L - L (X) / * The 98 Σ / 2 section of the reservoir belongs to the soufflopathic zone. With / L - L (X) / * 98 σ / 2 and / L - L (J) * 98 Σ / 2, the area is considered to be a zone that is not uniform in the strength x-rays of the coal and host rocks. With / L - L (J) / * 98 σ / 2 and / L - L (X) / * 98 σ / 2, the section of the reservoir belongs to the zone of geological disturbance. In this case, the values of all differences are taken in absolute value.

Description

The invention relates to mining and can be used in the development of coal-bearing gas.

The purpose of the invention is to improve the accuracy of determination of safe zones by taking into account the interrelationship of the gas and stress state of the formation

The method is carried out as follows.

In the clearing zone, coal is extracted by a combine and in the first cycle along the length of the cleaning face, the level of acoustic emission from the rock mass and the volume of gas released from the bottom during coal extraction are measured. The acoustic emission level is measured using a geophone, and the amount of gassing is measured using a methane sensor installed

 stationary in the outgoing jet of the slab. The value of the volume of gas evolution from the d-th site of the bottom in the i-th cycle of the notch is determined by the formula

I-m Z.iGjj-ISia-J.-lJAJ

J J Hg ;;

where G ;; - the volume of gas released from the bottom of the coal excavation in

 J

q i.

h

t; 5 I cycle during the extraction time of the j-ro plot, m3;

gas flow rate from the bottom of the coal excavation in the i-th cycle to the excavation of the j-ro section of the bottom, m3 / min;

the duration of the extraction of the j-ro of the area of the bottom in the i-th cycle of the excavation, min; gas emission attenuation coefficient, V 0.03 1 / min. After removing the coal strip along the entire length, the hole of the hole is re-drilled and the size of the safe zone before the next cycle is determined by the initial rate of gas release.

According to the data received in the first digging cycle

i; j Lc; x; s-; iki; LUI, J}

the level of acoustic emission in the jth site in the previous extraction cycle, the size of the safe zone in the jth site in front of the previous extraction cycle, m;

the size of the safe zone in the j-th section of the slaughter in the current cycle of excavation, m; the volume of gas release from the jth site at the previous excavation cycle, m3; amount of advancement

where is x

and,

)

thirty

Kj

; - "

35

40

ABOUT

At 7xfcj 2X, (the seismoacoustic regime of the reservoir is determined by differential-IQ and the relationship between the size of the safe zone and the level of acoustic emission is established as a formula

Ijj (X) l ;, j (X), 15 where B, b are the coefficients depending

from the geological conditions of the adopted coal mining technology and the method of roof control.

2Q.The relationship between the size of the safe zone and the volume of gas evolution is established as a formula.

Hj () ;. j (I) + KI.M -L; .i.j, where 1, j t (I) is the size of the safe zone of the 25j-ro site before the previous cycle

 -M

Lj.

J

K, n | -1

ABOUT

the volume of gas released from the j-ro section of the bottom in the previous excavation cycle, m3; movement of the j-ro site for the previous excavation cycle, m; coefficients depending on the geological conditions of the adopted coal extraction technology and the method of roof control.

Based on the established dependencies, the maximum difference is determined between the size of the safe zone, in the first cycle, the j-th region in the previous emission determined by the level of acoustics, and the size of the safe area.

The secondary notch cycle, m, determines the magnitudes of the correlation ratios hj. & h e r h x x the magnitude of the correlation ratio between the size of the safe zone and the level of acoustic emission; The% correlation ratio between the change in the size of the safe zone and the level of acoustic emission.

AT. L7 2xd, the seismic acoustic regime of the reservoir is determined static and the relationship between the size of the safe zone and the level of acoustic emission is set as

50

55

zones determined by the amount of gassing.

b- Max (lj- (X) -l (l) |. On subsequent cycles of the notch for each site at the same time, the parameter (X) and the value of gas emission are determined by the level of acoustic emission; the parameter d is the difference of these parameters. For jljj (X) -lj (I) JЈ G the size of the safe zone in the area of the bottom is determined by the formula

lij (i). Find "J

lij (x) +1 | (I) 2

-but

one;. (X) A (X;. +1) where A and a are coefficients depending on the geological conditions of the adopted coal mining technology and the method of roof control

At 7xfcj 2X, (the seismoacoustic regime of the reservoir is determined by differential-IQ and the relationship between the size of the safe zone and the level of acoustic emission is established as a formula

Ijj (X) l ;, j (X), 15 where B, b are the coefficients depending

from the geological conditions of the adopted coal mining technology and the method of roof control.

2Q.The relationship between the size of the safe zone and the volume of gas evolution is established as a formula.

Hj () ;. j (I) + KI.M -L; .i.j, where 1, j t (I) is the size of the safe zone of the 25j-ro site before the previous cycle

0

five

0

 -M

Lj.

J

K, n is the volume of gas released from the j-ro section of the bottom in the previous extraction cycle, m3; movement of the j-ro site for the previous excavation cycle, m; coefficients depending on the geological conditions of the adopted coal extraction technology and the method of roof control.

Based on the established dependencies, the maximum difference is determined between the size of the safe zone, in the first cycle determined by the level of acoustic emission, and the size safe

zones determined by the amount of gassing.

b- Max (lj- (X) -l (l) |. On subsequent cycles of the notch for each site at the same time, the parameter (X) and the value of gas emission are determined by the level of acoustic emission; the parameter d is the difference of these parameters. For jljj (X) -lj (I) JЈ G the size of the safe zone in the area of the bottom is determined by the formula

lij (i). Find "J

lij (x) +1 | (I) 2

515WW

When | 1st (X) -l; j (I)) G in the j-th section, the hole of the hole and the size of the safe zone 1; determined by the initial rate of gas evolution. With

with 1 1 ij -l; j (X) | - and | ; j -1 (I) - bottomhole mining

determine the gas emission from the bottom and determine the size of the discharge zone by it, calculate in the first excavation cycle the maximum difference between the size of the discharge zone, determined by the level of acoustic emission, and the size of the specified zone, determined by the gas release from the bottom,

of the array in the -th section, determine the Yu, and with the difference between these quantities

1 in each notch cycle, less or

equal to its maximum value, the size of the zone of safe unloading is taken to be equal to the arithmetic mean 15 value of the sizes of the unloading zone determined by the level of acoustic emission and gas release from the bottom, and when the difference is greater than its maximum value, the gas release from holes is determined and calculated by his size

f

unloading zone and (1) | and

are souffle roopasny. When | one; -1 (x) | G | G J J-y and. () Ј - site count

heterogeneous in terms of strength characteristics of the properties of coal and containing properties

kind of When | jj-1; (X) and | l; j - 6

-lij (D

  bottomhole part of the mountain

An array is defined as the zone of influence of a geological disturbance.

20

Claims (1)

Invention Formula The method of determining safe and dangerous zones of cyclic excavation of the inlet part of a gas-bearing coal seam, including drilling holes along the length of the lava and determining the level of acoustic emission, determining the dependencies between the parameters of the acoustic emission level and the size of the unloading zone in each extraction cycle, maintaining the coal control of the safe depth of excavation, establishing the length of the hazardous zones along the length of the bottom, characterized in that, in order to increase the accuracy 25 | l-l (x) | -х, where 1 - zone size unloading, determined by gas emission parameters from holes, 1 (1) is the size of the unloading zone, determined by gas emission from the bottom, 1 (X) - 30 is the size of the discharge zone, determined by the level of acoustic emission, O is the maximum absolute difference between 1 (X) and 1 (1), the section of the reservoir belongs to the souffle-hazard zone, and 35 | 1-1 (X) 11-1 (5, section the seam is considered a non-uniform zone according to the strength characteristics of the coal   - definition of safe zones by account-I,,, .i (5 the interconnection of gas and stress-40 and host rocks and at | l-l (I) j 5 and (X) j - the specified section of the plug state of the reservoir, while determining the size of the discharge zone by the level of acoustic emission along the length of the lava in each excavation cycle, is simply attributed to the zone of geological disturbance. 15 20 25 | l-l (x) | -х, where 1 - zone size discharge, determined by the parameters of gas emission from holes, 1 (1) is the size of the discharge zone, determined by gas emission from the bottom, 1 (X) is the size of the discharge zone, determined by the level of acoustic emission, O is the maximum absolute difference between 1 (X) and 1 (1), the section of the reservoir belongs to the souffle-hazard zone, and | 1-1 (X) 11-1 (5, section the seam is considered a non-uniform zone according to the strength characteristics of the coal They are referred to as a geological disturbance zone.