Collective characteristics of nano scale powders by coke moving bed filter

Approximately 500 thousand tons of dust are generated annually from electric arc furnace (EAF) for scrap melting in Japan. The dust contains a large amount of metallic components such as zinc and iron. It should be recycled by separating zinc from iron through high temperature reduction and evaporation processes. Conventional processes consume very high energy and 30% of dust is wasted without recycling, therefore a high efficiency process is expected to be developed. A novel simple process to recover these metals is proposed with less energy consumption. The process is a combined process of a coke bed filter and a zinc condenser, which can recover metallic iron and zinc by directly separating them from high-temperature dust, exhausted from electric arc furnaces. This paper deals with the separation characteristics of the dust in the gas stream by a coke packed or a moving bed filter. The EAF dust contains nano scale powders which behave differently from over micron size powders.