SU395594A1 - METHOD FOR DETERMINING THE FIRE DANGER OF THE DEVELOPED SPACE IN MINES - Google Patents

Description

I

The invention can be applied in the mining industry in determining the fire hazard of the mined-out spaces when developing the Krutope | Giving deposits of minerals by the underground method at the stage of Designing the ventilation of mining sites.

There is a known method for determining the fire hazard of the developed spaces, in which the degree of fire hazard is judged by the difference in the amount of incoming cleaning hole and outgoing air stream per 1 meter of Shield area (specific air leakage).

Such a pattern does not take into account the volumetric nature of the spread of air in the developed space; t cannot give an idea about the location (origin) of the fire and its size in the stages of mining the column.

The purpose of the present invention is to improve the reliability of the fire risk assessment.

This is achieved by determining the air filtration rate within the developed space and determining the size of the fire hazard zone from the values of fire hazardous filtration rates.

FIG. 1-3 shows diagrams illustrating the proposed method.

According to the invention, the values of noToiKa} of leaks and the descendant of 2 air suction in the extracted space 3 are determined, then the values of 4 initial rates of filtration in the developed space, i.e. the speeds at the air flow inlet into the developed space with CTOipoHbi of cleaning plant 5 or c are calculated. Surfaces 6. When the injection method of ventilation

plot flow / leakage (in the zone of the mining face 5 - surface 6) -; straight line l filtration rate, evenly distributed throughout the entire space. In the case of the injection method of ventilation, the assessment of the fire hazard of the exhausted space 3 is carried out by comparing the values of 4 initial filtration rates with their fire-hazardous values 7. With the suction and injection-suction ventilation methods, the degree of fire danger of space 3 is determined not only by the 4 initial velocities of the filter strain but also by the nature of their distribution in the streams / and 2. The velocity distribution

filtering streams 1 and 2 of different lengths

 about p

determined by the ratio 77

 and

10, and, 12, where Lx is the average filtration rate in a given flow section / or 2;

UH - average filtration rate at the beginning of the stream is 5 or 6. Then, at the initial speed

filtering 4 and ratios 8. 9, 10. 11, 12

respect

n

the character of the distribution of velocities 13, 14, 15, 16, 77 along the filtration flow and / or 2 and according to the values of fire hazardous filtration speeds 7 (from 0.28-10 to 1.1-1.0 m / s) is built, along the abscissa axis 18 determines the length of the fire hazardous section 19 of the filtration (Flow / or 2, defining the fire hazard zone, its location is 20 between 5 and 6.

Subject invention

The method of determining the fire hazard of the spent space in the shelves, including determining the amount of air filtered through the exhausted space, characterized in that, in order to improve the reliability of the fire hazard assessment, determine the air filtration rate within the developed space and: according to the values of fire hazardous filtration rates, determine the size fire hazard zone.

BUT

 tf / fy / / Ay /

/ W- --n- /;

j-t:.,;

OH-IO m / s

2.0

80J 100 n, m

FIG.