To optimize the flow sheet and process parameters of the production process, and to demonstrate the functionality of the selected technology, Keliber (“the company”) has designed three different test programs: continuous minerals processing pilot, continuous conversion pilot and continuous LiOH pilot.
The purpose of the continuous minerals processing pilot was among other things to enhance the classification process, to optimize the spodumene flotation and magnetic separation processes and to produce spodumene concentrate for further processing. Continuous minerals processing tests were conducted at the Mineral Processing and Materials Research unit of the Geological Survey of Finland in Outokumpu (“GTK Mintec”) in August 2019 and the results from the pilot program have now been reported. A total of 89 tonnes of spodumene ore from Syväjärvi was processed during the minerals processing pilot program.
Based on the results of the continuous test program, optimizing the process including the pre-float conditions and residence times in spodumene flotation increased the minerals processing lithium recovery to over 88 percent from 83.4 percent obtained in the previous pilot-scale test program conducted on the Syväjärvi ore in 2016.
During the 2019 minerals processing pilot program, a total of 10 tonnes of spodumene concentrate (Li2O of over 4.5%) was produced for further processing. The company expects the whole test program, including the continuous pilot test programs for conversion and LiOH processes and the related test run reports, to be completed by the first quarter of 2020.
“We are pleased that we have been able to further optimize the chosen minerals processing method and improve the lithium recovery. Our team has done an excellent job together with GTK Mintec specialists and researchers. We will continue the pilot-scale tests for the remainder of our production process,” says Pertti Lamberg, CEO of Keliber Oy.
