Dust Distribution of PM5 and PM10 in Large Mining Height Fully-Mechanized Face

In order to obtain the dust distribution of PM5 and PM10 in large mining height fully-mechanized face, the dust concentration around the shearer drum and along the downwind side of the shearer are measured under the conditions of the following wind and upwind respectively. The results show that when coal is cut in following wind, the initial concentration of PM5 and PM10 dust around the rear drum is high, then gradually decreases and becomes stable. The concentration of the front drum is low at first, and rises sharply after 70 to 80 s. When coal is cut in upwind, the initial concentration of the front drum fluctuates greatly, and the concentration of the rear drum rises about 10 s earlier than that in following wind. When coal is cut in following wind, the PM5, PM10 and total coal dust concentration reach the highest at the downwind of shearer around 10 m, then gradually reduce and tend to be stable at 40 m. The PM5 proportion is higher at first, and falls to the lowest at about 15 m, then rises again under the effect of wind. The PM10 proportion is on the decline overall. When coal is cut in upwind, the dust concentration reaches the highest at the downwind of shearer 6 m or so, and is stable about 20 m. PM5 accounts for 60% to 80%, while PM10 accounts for 65% to 95% under both conditions.