SGS MINERALS SERVICES – SGS T3 1001 10-2010 HARD ROCK LITHIUM PROCESSING LITHIUM EXTRACTION INTRODUCTION Liberation data are very important because they indicate the potential Lithium is found in very low concentration FROM SPODUMENE recovery of a mineral of interest (e.g., in igneous rocks. The largest spodumene and mica). Association data SGS Minerals Services has experience concentrations of lithium-containing illustrate the potential impurities in a with complete flowsheet development minerals are found in granitic pegmatites. concentrate or product. The liberation and to recover high grade lithium products The most important of these minerals association for each sample are calculated from hard rock lithium minerals. SGS are spodumene (Li O, Al O . 4SiO ) and 2 2 3 2 for each size fraction of the entire sample offers a multi-disciplinary team that is petalite (Li O, Al O . 8SiO ). Spodumene 2 2 3 2 based on the modal analysis of each involved from the initial stages of the has a theoretical Li2O content of fraction. Normally liberation increases characterization of the lithium deposit to 8.03%. Due to its high lithium content, from the coarse to the fine fraction. the production of a market sample of a spodumene is considered the most Metallurgical results show that a high high grade lithium product. important lithium ore mineral. A typical grade lithium concentrate (>7%) can be SGS provides the comprehensive range run of mine ore can contain 1-2% Li O, 2 achieved. of testwork capabilities required to extract while a typical spodumene concentrate lithium. These capabilities include: suitable for lithium carbonate production contains 6-7% Li O (75% - 87% GRINDABILITY TESTS •• Comprehensive high definition 2 spodumene). Higher grade concentrates mineralogy SGS supports the minerals and chemical with 7.6% Li O and low iron content are •• Extensive grindability test suite 2 industries in the design and operation of used in ceramics and more demanding •• Mineral separation (gravity, heavy efficient crushing and grinding circuits industries. liquid and heavy media) using both power and model-based •• Flotation methods. We can design bankable •• Pyrometallury (concentrate roasting MINERALOGICAL ANALYSIS OF A ­TYPICAL circuits and provide operating advice to and acid roasting) PEGMATITE DEPOSIT maximize milling efficiency, considering both steel and power consumption. •• Hydrometallurgy A typical pegmatite deposit can contain Our practical experience also ensures •• Pilot plant testing quartz, sodium-feldspar, spodumene, that we recommend effective circuit •• Environmental testing. lepidolite, petalite, lithiophilite, microcline, configurations that offer ease of operation and variable amounts of muscovite and maximum flexibility. (1-5%). One can also find trace amounts of Ta-Nb phases, commonly columbite, SGS performs the following grindability tantalite, and other accessory phases tests: such as spessartine, biotite, pollucite, •• SPI test amphibole and other minerals (Fe-Ti •• SMC test oxides, tourmaline, chlorite, apatite) •• Bond Ball Mill Grindability Test (Grammatikopoulos et al., 2009). •• Bond Impact Test SGS experts in High Definition Mineralogy •• Abrasion Test use the QEMSCAN® to identify and map •• JK Drop-Weight Test textural features of coarsely crushed •• MacPherson Autogenous Grindability samples. A typical assemblage includes Test sodium feldspar, microcline, spodumene •• MacPherson 18” Mill Test. and minor muscovite. False-coloured Well-instrumented pilot-scale autogenous images provide textural information on the grinding circuits, ball and rod mill circuits, occurrence of spodumene and associated and crushing circuits also facilitate testing minerals. and circuit design. After production starts, in-plant audits allow modeling and simulation to optimize existing plants.

Spodumene, Galileia, Brazil © Dave Berthelmy

SGS MINERALS SERVICES – SGS T3 1001 2

bullet and heavy media separation. CONCENTRATE ROASTING Gravity separation is feasible only if AND ACID ROASTING the spodumene is coarsely grained. Lithium can be extracted from SGS delivers on all physical separation spodumene concentrates after techniques, both at the laboratory scale roasting and acid roasting operations. and pilot plant scale. Depending on your A concentrate with at least 6% Li2O objective, the flotation concentrate can (approximately 75% spodumene) then be further processed by high- is suitable for roasting. Roasting is temperature techniques (pyrometallurgy) performed at about 1050°C, during which or chemical techniques (hydrometallurgy) spodumene will go through a phase to produce lithium carbonate or other transformation from α-spodumene to desirable lithium compounds. β-spodumene. The α-spodumene is virtually refractory to hot acids. FLOTATION As a result of the phase transformation, Flotation is used to generate a high grade the spodumene crystal structure expands spodumene concentrate (75-85% by about 30% and becomes amenable spodumene) suitable for lithium to hot sulphuric acid attack. Due to this extraction. expansion, the specific gravity of the False-coloured image of a crushed spodu- SGS’ expertise in flotation ensures you spodumene decreases from 3.1 g/cm3 mene pegmatite sample can: (natural α-spodumene) to around 2.4 g/ •• Generate a high grade concentrate cm3 (β-spodumene). MINERAL SEPARATION with high lithium recovery suitable After roasting, the material is cooled and Separation of lithium minerals can be for downstream roasting and then mixed with sulphuric acid (95-97%). efficiently achieved by taking advantage hydrometallurgy The mixture is roasted again at about of their physical, electrical and magnetic •• Maximize recovery 200°C. An exothermic reaction starts properties. Physical separations are •• Minimize acid-consuming at 170°C and lithium is extracted from performed by wet and dry screening, contaminants β-spodumene to form lithium sulphate, tabling and magnetic, electromagnetic, •• Minimize the cost of roasting. which is soluble in water. electrostatic, magnetohydrostatic

Petalite After Crushing Spodumene Flotation

Spodumene Concentrate Roasted Concentrate After Acid Roasted Concentrate SGS MINERALS SERVICES – SGS T3 1001 3

HYDROMETALLURGY PILOT PLANT TESTING RECENT PUBLICATIONS Working with the lithium concentrate, Pilot testing is the best way to reduce 1. Aghamirian, M., Mackie, S., Raabe, SGS’ team uses a standardized flowsheet technical risk associated with a new H., Lang, D., Grammatikopolous, to produce high grade lithium products flowsheet or flowsheet changes. It will T., Pearce, G., Todd, I., Imeson, D. such as lithium carbonate or lithium generate the data needed to design (2010). Lithium Extraction from hydroxide. These are reagents for the the full scale plant. As well, existing Spodumene. Hydroprocess 2010 III lithium battery industry. The multi-step operations can be simulated at the pilot International Workshop on Process process involves atmospheric leaching, scale to evaluate new technologies or Hydrometallurgy, August 11 – 13, liquid-solid separation and impurity address problems without interrupting 2010, Santiago, Chile. removal via precipitation and ion- production. In a pilot plant, the actual 2. Grammatikopolous, T., Gunning, exchange. Our team expertise can deliver: process is constructed from appropriately C., Pearse, G., Gelcich, S. (2009). •• High grade market samples of sized equipment and the testing allows us Quantitative characterization of lithium products using a standardized to address virtually all of the issues that a spodumene ore by automated flowsheet full processing plant will face. As a result mineralogy from the Moblan •• Process optimization based on the of many years of experience, our staff can Pegmatite Deposit, Quebec, Canada. unique properties of your material quickly provide workable alternatives. Proceedings of 48th Conference •• Process data in support of pre- of Metallurgists, COM 2009, feasibility and feasibility studies ENVIRONMENTAL TESTING August 23-26, Laurentian University, •• Capital and operating expense Environmental responsibility is a fact of Sudbury, ON Canada, pp. 65-76. modeling life in today’s industry. Corporations are •• Piloting of the optimized flowsheet. constantly confronted with new laws and CONTACT INFORMATION regulations so must spend a great deal of Email us at [email protected] time and money meeting environmental www.sgs.com/minerals requirements. This can include adapting extraction processes, investing in emission-reducing and energy saving technologies and conducting ongoing environmental investigations. SGS offers the following environmental services to help you meet these ongoing challenges: •• Acid rock drainage testing •• Water treatment services •• Laboratory testing •• On-site laboratories •• Mine site reclamation and closure A sample of high grade lithium carbonate planning •• Health & safety audits © SGS Mongolia – 2013 – All rights reserved - SGS is a registered trademark of SGS Group Management SA