Reducing Quartz Dust with Flooded-Bed Scrubber Systems on Continuous Miners.
Jayaraman-NI; McClelland-JJ; Jankowski-RA
NIOSH 1990 Sep:86-93
Techniques for reducing quartz (14808607) dust exposures in underground coal mines were evaluated. Respirable dust samples were collected by cyclones and impactors in the return flow of a continuous mining machine in a coal mine in Virginia in a preliminary study. The quartz content of the dust was determined. The dust suppression efficiency of a continuous miner operating in a coal mine in Illinois fitted with two flooded bed scrubbing panels was determined and compared with that of a continuous miner having only a single panel. The effect of modifying the cutting sequence of a continuous miner in a mine in Utah on quartz dust exposures was evaluated. The sequence was altered by eliminating grinding of the floor. A curtain was hung to the right side of the machine near the end of the blowing tube. The percentages of quartz in the samples collected by the cyclone which had a median diameter of 2.25 microns was higher than those collected by the impactor which had a 3.7 micron cutoff, 6.7 to 7.8 versus 2.8 to 4.0%. This was taken as evidence that the median diameter of quartz dust was smaller than that of coal dust. Reductions in total respirable dust concentration and the quartz fraction of the dust achieved by the continuous miner equipped with the single scrubbing panel averaged 40 and 15%, respectively. When a double panel was used the collection efficiency for both respirable dust and quartz dust was 72%. Using the modified cutting sequence and curtain reduced respirable dust exposures by approximately 50% and the quartz content of the dust by 60%. The authors conclude that the median diameter of quartz dust is probably smaller than that of coal dust. Doubling the number of scrubbing panels on continuous miners can sharply reduce the quartz content of respirable dust as well as the respirable dust concentration.
Dust-suppression; Mineral-dusts; Coal-mining; Underground-mining; Control-technology; Mining-equipment; Dust-analysis; Equipment-reliability; Respirable-dust;
Control Technology and Personal Protective Equipment; Research Tools and Approaches; Control-technology;
Proceedings of the VIIth International Pneumoconioses Conference