(General Information Release August 2005)
Maelgwyn Mineral Services (MMS) have successfully installed and commissioned the first fully commercial application of its new centrifugal floatation technology. The patented Imhoflot G-Cell pneumatic flotation technology utilises centrifugal forces to separate the froth from tailings. MMS have been developing the technology over the last four years.
Gebr. Dorfner GmbH & Co, Hirschau, Germany has successfully installed a 3 stage Imhoflot G-Cell flotation plant for kaolin recovery. Dorfner’s multistage hydrocyclone plant produced a middlings stream that previously did not fulfil industrial standard kaolin grades and was either used as quarry filler or sold to the cement industry. Dorfner chose the MMS flotation technology because of its low capital cost and the fact that it could produce the required grade of kaolin without the need of a cleaner flotation step. Testwork had determined that this was not possible with conventional tank flotation.
MMS were involved in consultations with Dorfner and significant laboratory test work was completed by both MMS and Dorfner to optimise the flotation reagent suite. To demonstrate the capability of Imhoflot G-Cells to handle the relatively high flow rates (due to the need to float at low solids densities) and their ability to obtain the desired grade and recovery without the need for a cleaning stage, a 1.7m diameter prototype G-Cell was pilot tested onsite using the entire middlings stream. This pilot testing proved the applicability of the G-Cells and determined the need for 3 G-Cells in series to obtain the desired recovery.
A 3 stage 1.8m diameter Imhoflot G-Cell plant was ordered by Dorfner in March 2005 and was installed and commissioned successfully in July 2005. The plant is capable of processing material at over 100m3/hr. The plant is able to produce a high grade Kaolin product at above 13.5% loss on ignition kaolin grade at a recovery of above 85%. Mass yields vary depending on the feed grade, but approximately 70% yield was achieved.
MMS presented a paper which included details of the Dorfner operations at the Randol Innovations in Metallurgy conference held in Perth, Australia, August 2005.