Explosibility of Victorian brown coal dust

Abstract

The explosibility of Victorian brown coal dusts has been investigated in a wide range of equipment, including the 1.2 dm3 Hartmann bomb and the 201 spherical bomb. The Hartmann bomb seriously underestimates the explosibility of brown coal dust and empirical relations between Hartmann bomb and spherical bomb results cited in the literature are not valid for brown coal. At its equilibrium moisture content, Morwell coal is explosive between 0.16 and 7.0 kgm-3 and the explosion severity peaks at 0.50 kgm-3. Explosibility increases with decreasing moisture content and particle size, and with increasing volatile matter content. The explosibility dust constant (Kst) for Victorian coals is as much as six times higher than that of Pittsburgh coal. For Morwell coal (21 μm), the transition from the St1 (explosive) to the St2 (strongly explosive) category occurs when the moisture content falls below 5%. © 1988.