Project Status: Complete
Project Participants: Alcoa, CSIRO
Project Leader: Craig Klauber (CSIRO)
A key platform of CSRP is support for waste minimisation and this will be partly achieved through the development of sound reuses for industrial by-products. CSRP can help facilitate the reuse of Wagerup red sand (industrial by-product), initially through demonstration of the separation of the sand into four fractions based on magnetic property.
The research objectives were for 10-12 tonnes of Wagerup sand to be separated into fractions based on magnetic property using Low Intensity Magnetic Separation (LIMS) followed by Wet High Intensity Magnetic Separation (WHIMS).
A pilot-scale quantity of Wagerup bauxite residue sand was screened and separated into fractions via WHIMS. The method proved capable of producing a high quartz low iron fraction that was up to 95 percent by weight silicon dioxide based on x-ray fluorescence (XRF) analysis.
The quality of the product was primarily dependent upon field strength and the silicon dioxide content had an excellent negative correlation with the iron oxide level.
The LIMS-WHIMS work has demonstrated that a viable high quartz low iron fraction is obtainable on a small pilot scale. In terms of a permanent high tonnage facility the key would appear to be the solid suspension feed. In this work the simplest approach of a stirred feed-tank on the ground and a diaphragm pumped line to a short residence time header tank was the easiest to implement, but this is not the best approach to take in practice. Much better control could be obtained with a high-solids feed system plus water into
an in-line mixing system direct into the WHIMS.