Defense Metals Corp. (TSXV: DEFN | OTCQB: DFMTF | FSE:35D) has announced that Phase I of its hydrometallurgical pilot plant at SGS Lakefield, has been successfully completed.
John Goode, consulting metallurgist to Defense Metals commented: “This first fully integrated pilot plant demonstration of the proposed Wicheeda hydrometallurgical process delivered exactly what was required of it. We have confirmed the general workability of the process, optimized certain design parameters, and identified areas that will be improved ahead of the Phase II pilot plant. The SGS Lakefield team did an excellent job of construction and operation of the circuit, and their efforts are much appreciated.”
The main objective of Phase I of the company’s pilot plant was to test the flowsheet for operability and identify any changes that might be required before conducting a longer test campaign. During the five days of continuous operation, the parameters for the unit operations were varied slightly to allow optimization of the circuit ahead of Phase II pilot plant run scheduled for late-April 2023.
Defense Metals is still receiving assays, and evaluation of the results has not yet been finalized.
However, to date, it has been reported that the extraction of Pr (praseodymium) and Nd (neodymium) from the acid bake calcine was more than 90%, the impurity removal circuits were very efficient, and reagent regeneration and water recirculation were effective. Defense will make minor changes to the circuit ahead of Phase II and an alternative product precipitant will be used.
The fully integrated pilot plant included sulphuric acid baking, water leaching, three stages of impurity removal, rare earth precipitation, magnesia regeneration and recycling, and process water recycle.
The plant ran continuously and without interruption for 24 hours a day over a total run time of 110 hours. Operations were handled by a total of ten SGS technicians and metallurgists on each of two shifts managed by senior day-shift staff.
To find out more, please visit www.defensemetals.com