Plasma Processing of Chlorinated Iron Oxide Waste for Fe Recovery

Abstract

Industrialization for economic growth is harming our environment with various gas emissions, wastewater, harmful dust, and solid waste. Solid waste with hazardous content is one of the main contributors to environmental illness. The chloride media leaching of iron from high-quality ilmenite (FeTiO3) produces TiO2 pigments and chlorinated iron oxide waste (CIOW) in solid form. Direct processing of CIOW is prone to flue-losses due to its fine particle nature (35- $75~\mu \text{m}$ ). Transportation of this waste can cause air pollution. A new methodology to treat the CIOW is defined in this article. The fine CIOW is beneficiated into pellets and smelted in an ecofriendly thermal plasma setup to yield marketable low sulfur pig iron and easy disposal (chloride-free) slag. Thermal plasma provides high temperature, high energy flux, and ionized-state condition to remove/destroy the toxic nature of CIOW. The impurity analysis of the CIOW shows that it contains 2.28%Cl, whereas the final slag after the process contains 0.007%Cl. The waste processing and recovery details are discussed in detail with appropriate characterization techniques such as chemical analysis, thermogravimetric and differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM).