LITHIUM GRAPHITE REEs
zinnwaldite. The L-Max Process has the potential to disrupt the lithium market by providing additional lithium supply from alternative sources.
On September 27, 2016 the company had announced the commencement of a prefeasibility study for a Phase 1 L-Max plant targeting production for 2019. The Phase 1 L-Max plant will be designed at sufficient scale to be economically viable at a lithium carbonate price of $ 8,000 / t and to prove that L-Max is technically robust under commercial operating conditions. Elsewhere, Lithium Australia says it has advanced commercialisation of the Sileach™ process for the recovery of lithium from silicates, by committing to the engineering design. An engineering study has been awarded to CPC Project Design Pty Ltd for the design of a plant with output of 2,500 t / y lithium carbonate for scheduled completion in April 2017.“ Commercial development of the Sileach process involves progressive de-risking and demonstration of the ability to scale up from laboratory tests through to commercial production. The revolutionary Sileach process is designed to recover lithium and other metals from any silicate, including spodumene, lithium micas, petalite, amphiboles, pyroxenes, tourmalines etc. The award of engineering design to CPC Engineering has propelled Lithium Australia along the path to commercialisation. Design studies will commence in December 2016 and will be an integral part of LIT’ s decision process to proceed with plant construction. The Sileach process is undergoing independent development and testing with our partners ANSTO Minerals( a division of the Australian Nuclear Science and Technology Organisation).
CPC Engineering will provide LIT with engineering design, capital cost estimates, operating cost estimates and comparative logistic costs of a number of Western Australian sites. Port Hedland remains a location of high priority to provide LIT with the greatest flexibility in servicing its requirements under the terms of LIT’ s commercialisation agreement with Pilbara Minerals. Successful large-scale pilot testing may lead to a 50 / 50 joint venture( the Sileach JV) between LIT and Pilbara Minerals to process spodumene from Pilbara Minerals’ Pilgangoora deposit which is located only 120 km south of Port Hedland. LIT and ANSTO have scheduled further pilot testing in December 2016 / January 2017 to process spodumene concentrates from Pilbara Minerals’ Pilgangoora deposit. Work has commenced at Murdoch University, funded by a research grant from the Minerals Research Institute of Western Australia. That work will focus on impurity deportment, and maximising the value of by-product credits.
Finally, DORFNER Analysenzentrum und Anlagenplanungsgesellschaft mbH( ANZAPLAN)
has been retained by European Lithium Ltd to manage process design for its Wolfsberg lithium project located in Austria. This is to be followed by pilot trials to produce larger quantities of concentrate forming a basis for engaging with offtake partners and the downstream testing of the conversion of lithium carbonate and lithium hydroxide for technical and battery use.
The Wolfsberg project is close to the largest lithium import markets in the European Union, which is a major lithium importer, consuming a quarter of the global market volume, second only to China. It is ideally located to serve the surging lithium demand with for example Samsung’ s SDI Battery Systems( SDIBS) plant in Graz, Austria being in close proximity of the project. Concentrates could also be marketed to the glass-ceramic producers in Europe that are currently importing material from Australia and South America.
Graphite developments
Glencore Technology has been involved with the graphite industry for over 20 years, with several Jameson Cells installed at the Ancuabe operation in Mozambique in the mid 1990s. The company told IM:“ However, the industry has been dominated by price slumps and peaks, with the most recent dramatic price increases between 2011 and 2013, having fallen back to sustainable levels. The continued interest in graphite, through the use of lithium batteries for electric vehicles and power grids, as well as graphene production, is offering opportunities for graphite projects worldwide.”
Graphite processing generally involves a flotation stage in its flowsheet, making the most of the natural hydrophobicity of the graphite. Due to the need to have high purity graphite concentrate, the cleaning stage in the flowsheet involves multiple stages of flotation cleaning using conventional cells, with three or four stages of cleaning not uncommon. However this results in circuits requiring large floor spaces and infrastructure, and high recirculating loads.
“ Work being done by Glencore Technology offers a better solution to conventional graphite
Mahenge PG-3 graphite concentrate from Ulanzi
cleaning circuits.” Virginia Lawson, Jameson Cell Manager at Glencore Technology commented:“ Two of the unique aspects of the Jameson Cell is the downcomer and wash water. The downcomer generates fine bubbles and creates high sheer forces, which provide the energy necessary for bubble contact with the graphite. Once the particles attach to the bubbles and pass out of the downcomer in the cell, they rise to the top of the cell. Prior to reporting to the concentrate launder the collected graphite is washed, ensuring the entrapped non floating gangue is washed out of the concentrate. The net result is a very clean concentrate being produced, able to achieve final grade concentrate from just one flotation stage.”
Lawson adds:“ We also think the graphite, a layered anisotropic mineral similar to molybdenum, also benefits from the turbulent and random collisions of particles and bubbles in the downcomer, while in a conventional cell, the minerals and bubbles tend to flow parallel to each other, following natural flow lines produced in the cell, reducing the chance of bubble and particle collision. Considering the small tonnages cleaned in most graphite circuits, and the superior grade recovery curves we have seen for testwork to date, it provides a good opportunity to include a small scale Jameson Cell at the head of a cleaning circuit to produce final grade concentrate. It can also be used in conjunction with conventional cells to target graphite composites with slow residence times. These circuits can then utilise small scale IsaMills™ to
56 International Mining | JANUARY 2017