Stable flow of off-gas dust from dust collector hoppers and storage silos is important for smooth operation. Flow properties of the collected off-gas dust are critical to achieve suitable flow. Various dust samples co...Stable flow of off-gas dust from dust collector hoppers and storage silos is important for smooth operation. Flow properties of the collected off-gas dust are critical to achieve suitable flow. Various dust samples collected from secondary copper smelter off-gases were studied. The median diameter of the fine-grained dusts varied from 0.8 to 1.4 μm and the flowability ranged from ＂cohesive＂ to ＂very cohesive＂. The flowa- bility of shaft and anode furnace dust improved slightly with increasing consolidation stress and their wall friction angles decreased, which is a typical behavior. In contrast, the flowability of converter dust decreased with increasing consolidation stress and its wall friction angles increased. Pre-shear treatment of converter dust worsened its flowability, increased the wall friction angle, and improved the flowabil- ity with increasing consolidation stress. This is believed to occur because pre-shear treatment fragments small agglomerates in the dust that improve flowability. The presence of such agglomerates was con- firmed by sieving tests. A diagrammatic representation of the flowability showing that the unconfined yield strength is dependent on consolidation stress can be improved by using logarithmically scaled axes.展开更多
文摘Stable flow of off-gas dust from dust collector hoppers and storage silos is important for smooth operation. Flow properties of the collected off-gas dust are critical to achieve suitable flow. Various dust samples collected from secondary copper smelter off-gases were studied. The median diameter of the fine-grained dusts varied from 0.8 to 1.4 μm and the flowability ranged from ＂cohesive＂ to ＂very cohesive＂. The flowa- bility of shaft and anode furnace dust improved slightly with increasing consolidation stress and their wall friction angles decreased, which is a typical behavior. In contrast, the flowability of converter dust decreased with increasing consolidation stress and its wall friction angles increased. Pre-shear treatment of converter dust worsened its flowability, increased the wall friction angle, and improved the flowabil- ity with increasing consolidation stress. This is believed to occur because pre-shear treatment fragments small agglomerates in the dust that improve flowability. The presence of such agglomerates was con- firmed by sieving tests. A diagrammatic representation of the flowability showing that the unconfined yield strength is dependent on consolidation stress can be improved by using logarithmically scaled axes.
