The research results have been published in the Journal of Mining Institute (Empress Catherine II Saint Petersburg Mining University).
On March 10, 1906, one of the most tragic accidents in the history of the mining industry occurred at the Courrières coal mine in France. An explosion of firedamp (mine gas) led to the detonation of coal dust. Mine supports were destroyed, and a fire broke out, claiming the lives of 1,099 miners.
By that time, coal miner's lamps—enclosed sources of lighting in mines, which were incomparably safer than the torches used previously—had already been invented. Ventilation systems to reduce methane concentration had become standard. However, this proved insufficient.
Today, the quality of ventilation systems has advanced significantly, dust suppression systems have emerged, intrinsically safe equipment is used, and gas drainage and degasification mechanisms are being improved. With the development of digital technologies, monitoring of mine spaces has become significantly more effective. Nevertheless, accidents periodically occur at coal enterprises worldwide, which means scientists are constantly searching for innovative solutions to provide mine safety.
the Journal of Mining Institute published an article by a group of scientists from Yazd University, Yazd, Iran entitled "Determination of suitable distance between methane drainage stations in Tabas mechanized coal mine (Iran) based on theoretical calculations and field investigation." The research aims to improve the degasification process by selecting the optimal distance between clusters of degasification boreholes.
Coal mine methane degasification must be performed when ventilation air cannot dilute methane emissions in the mine to a level below the permitted limits. One of the degasification methods is the use of cross-measure boreholes. Boreholes are drilled from the roadway heading to the fracture zone in the roof or floor strata of a mined seam. This is the main method used at the Tabas Coal Mine No. 1, where the research was conducted.
Using methane sensors and anemometers (which measure air flow velocity) installed on the longwall panel, the scientists measured the methane content in ventilation currents and the amount of drained methane for different borehole layouts. Analysis of the obtained data led to the conclusion that the highest degasification efficiency is achieved with a distance of 9-12 meters between between methane drainage stations.
The scientists also established that effective methane degasification in coal mines not only improves safety but also increases productivity at mining enterprises.
