Ferrochromium and ferronickel which are obtained from the reduction of chromite and laterite ores , respectively, are the important alloying materials in the production of stainless steel. The present study is possibly the first of its kind related to production of crude stainless steel melt by direct smelting of chromium and nickel ore without use of ferrochromium and ferronickel alloys. The feasibility of producing Fe-Ni-Cr crude alloy by direct smelting of chromite and laterite ores from local sources with activated carbon as reducing agent at 1400 o to 1550 o C using graphite crucible under argon atmosphere were conducted in a vertical tube furnace. It was found that the grade and composition of chromite and laterite ores are the main factors to produce the alloy. The smelting of 10-13% SCO chromite ore and 87-90% LIM laterite ore produced alloys with average iron, nickel and chromium content about 82%, 6.22% and 2.17%, respectively, at an average iron, nickel and chromium recovery of 98%, 97% and 87%, respectively. The high recovery of iron and nickel in the alloy indicates a high reducing condition in the smelting experiment. It is also shown that the solubility of Ni in the slag increases with Ni concentration in the alloy and the FeO concentration in the slag.
Chromite and laterite ores from local sources were smelted in a vertical tube furnace with activated carbon as reducing agent at 1400°C to 1550°C using graphite crucible under argon atmosphere. It is shown that the grade and composition of the ore are the main factors determining the feasibility of smelting a mixture of chromite and laterite ores to produce a Fe-Ni-Cr crude alloy. The high recovery of iron and nickel in the alloy indicates the highly reducing condition prevailing in the smelting reduction experiments. It is also shown that the solubility of Ni in the slag increases with Ni concentration in the alloy and the FeO concentration in the slag. The chromium content of the slag increases with increasing iron content of the slag.
This study was conducted to determine the non-isothermal and isothermal reduction of chromium ores in the solid-state by reductants like solid carbon under argon and hydrogen-argon atmosphere. Two different chromite ores from local sources , sandy chromite ore from Opol, Misamis Oriental (SCO) and lumpy chromite ore from Manticao, Misamis Oriental (LCM) were used in the study. Isothermal and non-isothermal experiments were conducted in a fixed bed reactor heated in a vertical tube furnace in the temperature range 800 to 1000°C. Raw chromite and reduced samples were subjected to phase analysis and morphology characterization using X-ray flourescence (XRF), X-ray diffraction (XRD), and energy dispersive x-ray spectroscopy (EDX). It was found that reduction does not go to completion at this temperature range. The early stage of reduction of iron was controlled by nucleation and the later by nucleation or chemical reaction or both. The activation energy at the early stage of reduction is estimated to be 44.76 kJ/mol and the later stage of reduction is 144 kJ/mol for SCO and 76.5 kJ/mol for LCM. The reduction of chromium was controlled by chemical reaction.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.