Pneumatic Transportation of Mine Run Coal Underground.
Min Cong J 1971 Dec; 57(12):42-46
A practical, pneumatic system for moving coal from the mine face to surface might increase continuous miner operating time and also reduce the incidence of coal mining accidents. The U.S. Bureau of Mines is developing information in pilot-plant experiments that can be used to determine system feasibility.
Min. Cong. J., V. 57, No. 12, December 1971, PP. 42-46