Research solutions to reduce dust concentration at the VM - L (7) - 1 mechanized longwal of the Mong Duong coal mine

Abstract

Mong Duong coal mine is currently exploiting from -97.5 m to -250 m with an output of 1.45 million tons/year, of which 1.35 million tons are from longwall mining and 100 thousand tons from dig tunnel in coal. To meet the production requirements of the mine, 5 blasting longwall have been mobilized with a total output of 1.0 million tons/year and 1 mechanized longwall with an output of 350,000 tons/year. At the mechanized longwall VM - L (7) - 1 of Mong Duong coal mine after the time of putting into use, there was dust concentration exceeding the allowable limit according to QCVN 05:2013/BTNMT. The article has researched, analyzed, assessed geological - mine conditions, mining technology characteristics, dust concentration, temperature, humidity and wind speed at furnace mirrors, and proposed suitable solutions to minimize dust generation, improve microclimate conditions (temperature, humidity and wind speed) at mechanized longwall. The solution selected and applied is the mist spraying at the mechanized longwall VM - L (7) - 1. After applying the solution in practice, it has brought effective results, minimized dust concentration in all working stages of the mechanized kiln VM - L (7) - 1. The applied results show that the dust concentration is within the allowable limit according to QCVN 05:2013/BTNMT (dust concentration in production stages decreased from 16.25% to 85.5%).