111 / 2021-09-30 16:10:12

Mining of longwalls with a high concentration of methane at TAURON Wydobycie S.A. ZG Brzeszcze, methods of ventilating, monitoring and combating the methane hazard andthe economic use of the captured methane.

methane, ventilation, methane drainage, methods of ventilation, fighting hazards, mining

Abstract of the article entitled:

Mining of longwalls with a high concentration of methane at TAURON Wydobycie S.A. ZG Brzeszcze, methods of ventilating, monitoring and combating the methane hazard and

the economic use of the captured methane.

 

 

The subject of the article is the practical experience of Zakład Górniczy Brzeszcze in the mining of longwalls with a high concentration of methane in the western part, in seams: 364 – a longitudinal mining system with a roof fall, and 510 – a diagonal exploitation system along the seam rise with a roof cave-in.

Currently, in Zakład Górniczy Brzeszcze, mining works are carried in the longwalls of the abovementioned seams.

Zakład Górniczy Brzeszcze is one of the mines with the highest concentration of methane in Polish mining. The average total methane bearing capacity for the period from January to September 2021 reached 165 m³/min. - maximum 172 m³/min. An average of 93.8 m³CH⁴/min was removed, which gives an average efficiency of 56.8%. The process of methane drainage in the mine started in 1969; by the end of 2020, approximately

1 575 000 000 m³ of pure (100%) methane was captured.

The currently exploited seam number 364 in the western part belongs to IV category of methane hazard, class B coal dust explosion hazard and III group of spontaneous combustion. In the years 2017 - 2021, mining works in this seam were carried out in longwalls Nos. 122, 125 and 126, whose maximum absolute methane capacity ranged from approx. 24 to approx. 50 m³/min. The effectiveness of methane drainage carried out during exploitation in the above longwalls ranged from approx. 20 to approx. 65%. Another exploited seam 510 is classified as IV category of methane hazard, I category of gas and rock outburst risk, I degree rock burst risk, class B coal dust explosion hazard, and III group of spontaneous combustion. In the years 2017-2021, mining works were carried out in longwalls Nos. 01, 02 and 05, the maximum absolute methane capacity of which ranged from approx. 54 to approx. 87 m³/min. The effectiveness of methane drainage carried out during exploitation in the above longwalls ranged from approx. 50 to approx. 65%.

Such high methane release during exploitation requires comprehensive methods of methane prophylaxis during exploitation works. The basic task is to ensure an appropriate level of safety for the staff and mining plant operations during the works and to maintain continuity of works. Any disruption of operation due to methane hazard may increase the fire risk.

Based on the experience gained by the mine staff, the authors of the article have presented two methods of longwall ventilation ensuring a high level of methane drainage efficiency as well as a methane hazard monitoring method and a methane drainage system used. It is the "U" method of ventilating with the so-called separation roadway used in the exploitation of seam 364 west and the so-called “short Y” method of ventilation with double ventilating roadways applied in the mining of seam 510 west.