Effect of Density on the Reduction of Fe2O3 Pellets by H2-CO Mixtures

• Main Author: Dongchen, Wang
• Format: Others
• Language: English
• Published: KTH, Materialvetenskap 2012
• Subjects: Hematite; direct reduction; density; carbon deposition; reduction mechanism.
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-100933

This study aims to find how density affects the reduction extent and reduction rate. H2-CO gas mixture is used as reducing agent. Five groups of different density pellets were reduced at four different temperatures. Light optical microscope (LOM) and scanning electron microscope with energy dispersive X-ray spectroscopy (SEM-EDS) used to detect completely and partially reduced pellets to investigate how density affects the reduction mechanisms. Results illustrate that density affects reduction extent and reduction rate a lot. However, when reaction temperature is 1123 K, density has less influenc on reduction extent. The carbon deposition occurred for high density pellets at 973 K and 1023 K. The reduction process cannot be described by a single rate controlling step. Reduced layer is denser compared with unreduced layer. Reaction at initial stages goes much faster than later stages.