Ignition characteristics of metal dusts generated during machining operations in the presence of calcium carbonate

Metal dust explosions in machining industries have caused large losses in recent years. In order to evaluate and control the ignition likelihood of metal dusts generated during machining operations, it is necessary to determine the ignition characteristics such as minimum ignition energy (MIE) and minimum ignition temperature (MIT). The aim of this paper is to investigate the inerting effect of calcium carbonate (CaCO3) on these ignition characteristics. Six kinds of typical metal dusts and two kinds of pure atomized metal powders were used to determine the MIE and MIT of dust cloud in the presence of CaCO3. To provide a practical guidance for metal dust explosion prevention, the recommended percentage of CaCO3 were discussed based on the inerting effect.