Journal of Material Sciences & Engineering

Recovery of Metals from Dry Shot Blast Waste Generated in the Stainless-Steel Production Process

Abstract

Khumkoa S, Chandakhiaw T, Ma-ud N, Khamseetha P, Hathong P, Laokhen P and Kansomket C

Dry shot blast generated during stainless steel production contains high content of valued metals such as iron chromium and nickel. These metals are in the form of oxides and it can be used as a raw material in iron and steel. This work aims to study the feasibility of metals recovery from dry shot blast by smelting reduction process. Smelting reduction of dry shot blast by using coking coal as reductant was conducted in an induction furnace. The effect of metallurgical parameters e.g. stoichiometry ratio of reductant per oxygen containing in dry shot blast, CaO/SiO₂ of slag forming and CaF₂ in slag, on %recovery of metal product was investigated. The results based on this study showed that the weight of metal product increases with increased the amount of coke to about 1.5 of stoichiometric molar ratio. Increasing of coke above this amount leads to decrease %recovery of metal product. Moreover, the weight of metal product is increased when the ratio of CaO/SiO₂ in slag decreased from 2 to 1. The chemical composition of the metal product is in the range of commercial grade and it can be used as raw materials to produce steel and cast iron alloy.Dry shot blast generated during stainless steel production contains high content of valued metals such as iron chromium and nickel. These metals are in the form of oxides and it can be used as a raw material in iron and steel. This work aims to study the feasibility of metals recovery from dry shot blast by smelting reduction process. Smelting reduction of dry shot blast by using coking coal as reductant was conducted in an induction furnace. The effect of metallurgical parameters e.g. stoichiometry ratio of reductant per oxygen containing in dry shot blast, CaO/SiO2 of slag forming and CaF2 in slag, on %recovery of metal product was investigated. The results based on this study showed that the weight of metal product increases with increased the amount of coke to about 1.5 of stoichiometric molar ratio. Increasing of coke above this amount leads to decrease %recovery of metal product. Moreover, the weight of metal product is increased when the ratio of CaO/SiO2 in slag decreased from 2 to 1. The chemical composition of the metal product is in the range of commercial grade and it can be used as raw materials to produce steel and cast iron alloy.