Impact on the Reduction Process of Carbon Containing Pellets with Biomass Replacing Traditional Reducing Agent

Abstract:

Considering the rotary hearth furnaces (RHF) direct reduction process, using bamboo char, charcoal and straw fiber as reducing agents added into the carbon containing pellets, the experimental study on the impact of reduction effect has been conducted from metallization rate, compressive strength and volumetric shrinkage. Test results showed that biomass reducing agents can replace traditional reducing agents used in the RHF direct reduction process. Compared with traditional reducing agents, biomass has less of effect on metallization rate, but different biomass reducing agents have large impact on strength and volumetric shrinkage of pellets. The compressive strength of pellet with straw fiber is relatively higher, and the compressive strength of pellets with charcoal or bamboo charcoal is low, for reaching the production requirement, which will be improved at higher temperature (1300°C). Using bamboo charcoal as reducing agent will lead to the swell of pellets in the beginning stage, and this situation will make the volumetric shrinkage at high temperature lower, finally, all of these will affect the strength of pellets and the heat-transfer between different material layers, thus it should be used accompanying with other reducing agent.

• Periodical: Advanced Materials Research (Volumes 1120-1121)
• Pages: 1302-1307
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1120-1121.1302
• Online since: July 2015
• Authors: Peng Yuan, Hong Liang Han, Dong Ping Duan*
• Keywords: Biomass, Compressive Strength, Metallization Rate, Rotary Hearth Furnace, Volumetric Shrinkage

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