Abstract View
Characterizing Potash Rock Dust Generated from Full Scale Cutting Tests Performed with Three Different Radial Pick Wears
SYD SLOUKA, Muhammad Ishaq, Jamal Rostami, Jürgen Brune, Colorado School of Mines
Abstract Number: 32
Working Group: Health-Related Aerosols
Abstract
Respirable dusts pose serious long-term health issues to occupational workers where mechanized mining and tunneling machines are used in hard rock excavation. This is particularly true for the U.S. coal mining industry. Various mechanical excavation machines, such as longwall shearers, efficiently cut rock by striking the rock surface with hardened steel and tungsten carbide picks. Fine, breathable, rock dust is generated each time the pick tip contacts the rock surface and during the regrinding of the cuttings at the face by the loading process. In underground mines and tunnels, the respirable dust generated from cutting is also carried further down the production line by the ventilation air current or reintroduced into the air at transfer points, potentially exposing numerous miners.
This study characterizes and compares the respirable rock dust particles generated at the pick tip as a function of pick wear. Parameters studied include dust quantity, size distribution, mineralogy, and particle shape throughout the life-cycle of the pick. Results provide some insight to mine and tunnel operators for changing out picks to mitigate dust at the generation point related to the cutting process. Testing was performed on a linear cutting machine (LCM) which allows for full scale cutting tests in a laboratory environment. For this study, a dust collection system was designed and built to collect dust samples from LCM testing. Potash rock samples were used in these preliminary experiments with radial picks at new, moderately, and fully worn wear levels. Results show statistically significant effects of bit wear on dust parameters. Follow up testing is underway on other rock samples using different cutting tools.