关键词: 粉尘爆炸, 粉尘层, 粉尘云, 最低着火温度, 防爆设计

Abstract: An experimental setup was established according to IEC standard to investigate 8 kinds of dust concomitant with grain for their MITs of dust cloud and layer(MITC and MITL), which were sampled in-situ from actual grain processing line. The influences of inorganic ash, particle size and moisture on MIT were thus tested. It was found that in grain handling process the late phase is even more hazardous than the early phase, and the safety margin in existing explosion-proof design procedure based on the data of refined flour and starch is excessive in practice. Some parameter sets as practical temperature criteria are therefore put forward on the experimental basis for selecting properly explosion-proof equipment in grain processing industry. They will be of importance to the evaluation of dust ignition/explosion hazards.