Minimum ignition energies of pure magnesium powders due to electrostatic discharges and nitrogen's effect

摘要

This paper experimentally investigated the relation between the minimum ignition energy (MIE) of magnesium powders as well as the effect of inert nitrogen (N-2) on the MIE. The modified Hartmann vertical-tube apparatus and four kinds of different-sized pure magnesium powders (median particle size, D50; 28.1 mu m-89.8 mu m) were used in this study. The MIE of the most sensitive magnesium powder was 4 mJ, which was affected by the powder particle size (D50; 28.1 mu m). The MIE of magnesium powder increased with an increase in the N-2 concentration for the inerting technique. The magnesium dust explosion with an electrostatic discharge of 1000 mJ was suppressed completely at an N-2 concentration range of more than 98%. The experimental data presented in this paper will be useful for preventing magnesium dust explosions generated from electrostatic discharges. (C) 2016 Elsevier Ltd. All rights reserved.