Numerical modeling & microwave roasting of refractory gold ore
Loading...
Authors
Honaganahalli, Puttanna S.
Issue Date
1994
Type
Thesis
Language
en_US
Keywords
Gold , Ore , Refractory , Numerical Modeling , Microwave Roasting , Bio-oxidation , Dielectric , Electromagnetic , Mackay Theses and Dissertations Grant Collection
Alternative Title
Abstract
Microwave roasting of refractory ores is an attractive alternate to conventional thermal roasting. Temperature measurements and hence temperature control is a major problem which is obstructing the introduction of this new technology to mineral processing. This thesis presents a mathematical model of determining temperature continuously and suggests control of temperature as a function of time of roasting. The mathematical model was applied to two types of refractory gold ores viz. carbonaceous and sulfidic gold ores. The model was tested for three different power levels of 133, 298 and 531 kW/sq.m . The temperatures predicted by the model and the transient temperature plots which enable control of temperature are presented here. The temperatures for sulfidic ore was always found to far higher than that for carbonaceous ore for a given input power and time of irradiation. Power absorption efficiency for sulfidic ores was at 55% while for carbonaceous ore it was a dismal 20%. Steady state was achieved very rapidly in all cases and irradiation beyond this time would only lead to dissipation losses of energy. Preliminary investigations qualitatively confirmed the theoretical results. The recovery of gold with sulfidic ore was higher because it got roasted at the limited power levels that was applied. Scanning electron microscope studies showed size reduction of the ore particles which suggested capabilities of improved mass transfer of the lixiviant and promise of enhanced recoveries.
Description
Online access for this thesis was created in part with support from the Institute of Museum and Library Services (IMLS) administered by the Nevada State Library, Archives and Public Records through the Library Services and Technology Act (LSTA). To obtain a high quality image or document please contact the DeLaMare Library at https://unr.libanswers.com/ or call: 775-784-6945.
Citation
Publisher
University of Nevada, Reno
License
In Copyright(All Rights Reserved)