- This event has passed.
MSE GRADUATE SEMINAR
October 24 @ 12:00 pm - 1:00 pm
Date: Thursday, Oct 24, 2019
Time: 12:00 p.m.
Title: Thermal Concentration of Nickeliferous Pyrrhotite Concentrates for Nickel Recovery
Presenter: Feng Liu (PhD Candidate)
Supervisors: Prof. Mansoor Barati, Dr. Sam Marcusen
Nickeliferous pyrrhotite (Pyrr, Fe1-xS, x = 0-0.125) tailings are generated during beneficiation of sutfidic Ni-Cu ores, and are reported to contain on average ~o.80 wt% Ni for the operations in Sudbury, Canada. Direct disposal of this reactive waste material could lead to not only the formation of acidic effluents via oxidative dissolution, but also significant losses of Ni value. To address these issues, a thermal concentration process is under investigation, in which the nickel is recovered in the form offerronickel alloy.
One of implementations of thermal concentration is to blend Pyrr with metallic Fe and treat the resulting mixture at 850-950 °C in flowing Ar. Previous diffusion couple studies have shown that the interaction between Pyrr and metallic Fe, i.e., iron sulfidization plays a major role in forming ferro nickel alloy. In this talk, kinetic studies which were conducted to determine the rate-limiting step when metallic Fe was sulfidized by Pyrr will be first discussed. The results reveal that the iron sulfidization by Pyrr follows the parabolic law, which means the rate of reaction is inversely related to time and continuously decreases as the product layer thickens. The second part of this talk will focus on the lab-scale thermal concentration tests, in which the effects of operating parameters including treatment temperature, time, and Fe addition on the Ni extraction from Pyrr to metallic Fe were investigated. These optimization studies will provide a useful guide to the design and implementation when the cheaper iron source, e.g., iron oxide is used.