Study of Kinetics of Mill Scale Reduction: For PM Applications

摘要

Mill scale is a very attractive industrial waste due to its promising scope in many applications. Recovery of iron powder from iron oxide in mill scale could be considered as a method of beneficiation. The reduction of ground and powdered mill scale from rolling mill was studied using hydrogen gas as the reducing agent. The mill scale was subjected to low and high energy milling in order to increase the kinetics of the process by increasing the surface area of the sample bed. A thermodynamic study has been done on the reactions involved in the reduction process. This study focuses on improving the kinetics of process thereby achieving higher reducibility with the experimental variables being time, temperature and surface area of the mill scale powder. Vantoff equation was used for determining the first-order kinetics of the reduction reaction. The activation energy was calculated to be 47.3 kJ/mol and the iron content in reduced mill-scale powder was 90 % by weight.