Influence of Reduction Temperatures on Reduction of FeO-Containing Slag by Agricultural Waste

Abstract:

Generally, the conventional carbon sources such coke/coal are used in EAF steelmaking attributed the highest growth rate in energy consumption. A substitute routes striving to improve energy efficiency by providing auxiliary sources is essential. The unique features such high carbon content, surface area, porosity and low sulphur was available in agricultural waste clearly have the potential to be used as reducing agent in steelmaking process. The present study investigated the reduction behavior of EAF slag and production of metallic iron by reduction process. The carbon materials, coke and palm char (pyrolyzed via chemical activation) were used as reducing agent composite with EAF slag respectively. The reduction reaction was conducted in horizontal tube furnace at different reduction temperatures (1250°C, 1350°C, 1450°C and 1550°C) under argon gas (flow rate 0.01L/min) within 20 minutes. The reduced sample was examined by X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM) to understand the reduction behavior of both composite samples. Palm char showed more efficient due to improvement in degree of FeO reduction which was 57.72% compared to coke, 26.72%. The phase movement from iron oxide to iron was influenced by the reduction temperatures. XRD pattern revealed that the metallic iron was initiating appeared at temperature 1250°C and completely reduced at temperature of 1550°C . Predominant peak of metallic iron and the other oxides was clarified by EDS spectra. This study found that palm char has viability to be used as carbon sources in steelmaking applications.

• Periodical: Materials Science Forum (Volume 888)
• Pages: 441-446
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.888.441
• Online since: March 2017
• Authors: Anis Nadhirah Ismail*, Nur Farhana Mohd Yunos, Shamsul Baharin Jamaludin, Muhammad Asri Idris, Mohd Hakim Ibrahim, Veena Sahajwalla
• Keywords: Coke, EAF Slag, Metallic Iron, Palm Char, Reduction Behavior

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