The electric vehicle and battery markets are calling for unprecedented amounts of lithium; in 2016, demand for the lightweight metal rose by 26%, and is predicted to climb an additional 39% in 2018. By 2025, experts anticipate demand is likely to increase by a staggering 73%.¹
Lithium is used in a variety of applications, most notably in glass and ceramics, but its recent surge in popularity is courtesy of its use in batteries, particularly those employed in electric vehicles.
While lithium can be derived from a variety of sources, one source of lithium looks to be making a resurgence in the effort to meet future lithium demands: spodumene.
Demand for Lithium
A number of the industry’s largest players have announced their commitment to replacing the current fossil-fueled vehicle fleet with a much more sustainable electric offering. Add to this the expanding electronics market and lithium-ion batteries have never been more in demand.
Lithium-ion batteries are the battery of choice in electric vehicles, largely due to their weight to energy ratio. A recent report by Grand View Research anticipates a 17% CAGR up to 2025 for the lithium-ion battery market, landing on a 93.1 billion dollar market value.
Lithium was also recently recognized in the Critical Mineral Resources of the United States—Economic and Environmental Geology and Prospects for Future Supply – in which the USGS outlines a number of minerals deemed as critical to the economic prosperity and security of the nation.
Lithium from Spodumene
Spodumene is a lithium mineral derived from pegmatite rock. Known for its high lithium content, spodumene is the most widely exploited mineral source of lithium. Other lithium-bearing pegmatite silicates include lepidolite and petalite.
At one time, spodumene was the primary source of lithium production, but the industry transitioned to extracting lithium from brines because of the significantly lower operating costs. As a result, producers focused on developing brine deposits, while spodumene sources remained largely ignored.
However, exploding demand for lithium is calling for more lithium-bearing resources than ever before. This, in combination with spodumene’s high lithium content, has made the exploration for and development of spodumene deposits a highly attractive endeavor. In addition to its high concentration of lithium, lithium extraction from spodumene also typically offers lower capital costs and a shorter time from discovery to production in comparison to brine operations.
Extracting Lithium from Spodumene
The extraction of lithium from spodumene ore requires a number of steps – outlined below. It’s important to note that there are many variations on this process and the sequence described here is only one example.
Concentration and Drying
The processing almost always begins with concentration via crushing, grinding and froth flotation, followed by drying in a rotary dryer to produce a dried lithium concentrate.
Conversion to Beta-phase
Dried lithium concentrate is then processed in a rotary kiln (calciner) to convert the spodumene from alpha to beta phase, in order to make it more amenable to reaction.
Sulfuric Acid Digestion
From here, the beta-phase concentrate frequently undergoes sulfuric acid digestion via mixing in a paddle mixer (aka pugmill mixer). Paddle mixers are often the mixer of choice due to their heavy-duty construction, though care must be taken to choose materials that will be able to withstand the highly corrosive processing environment of sulfuric acid digestion.
After digestion, acid roasting is a common step. Again, this is typically carried out in a rotary kiln. Some processes may utilize a rotary cooler following the roasting step in order to reduce the temperature of the material for subsequent handling. Here again, materials of construction must be highly resistant to the corrosive nature of the material being processed.
The resulting material is water soluble lithium sulfate, which goes through a hydrometallurgical process to produce either lithium carbonate or lithium hydroxide.
Lithium can be produced into a variety of grades, referring to the purity of the product, but lithium-ion batteries require an especially high purity lithium, typically more than 99.5%. This can be derived from either of the lithium chemicals that can be produced from the processing of concentrates described above.
While lithium carbonate has largely dominated the market, lithium hydroxide has become the preferred lithium compound for batteries as a result of the advantages it can offer over lithium carbonate – namely, a longer battery life and larger capacity.
Noteworthy Spodumene Projects
A number of spodumene projects have been making headlines as of late, with some of the most prominent listed below.
Pilgangoora Lithium-Tantalum Project
Pilbara Minerals’ wholly owned Pilgangoora Lithium-Tantalum Project, located in Western Australia, is being recognized as a globally important source of spodumene, with offtake agreements already in place.
Pilbara Minerals recently announced a 22% increase in the total Measured, Indicated and Inferred Resources at the site. Future drilling is expected to yield further significant increases.
Bald Hill Project
Dry commissioning is under way at the Bald Hill Project, also in Australia, where spodumene concentrates are expected to be produced soon, with first shipment of lithium concentrate expected in the first quarter of 2018, according to co-owner Tawana Resources.
The Manono Project
The Manono Project in the Democratic Republic of Congo has been making headlines for its potential to be one of the largest lithium-bearing deposits in the world. Australia-based AVZ Minerals, part owner of the project, recently announced their findings of a 295.05m thick intersection of spodumene bearing pegmatite – a highly promising discovery.
The Hidden Lake Project
The Hidden Lake Project, located within Canada’s Yellowknife Lithium Pegmatite Belt, has also been in the news, with promising findings of high grade lithium ores.
Owner 92 Resources recently joined forces with Far Resources on the project. The completion and successful production run of the project’s Dense Media Separation (DMS) mini pilot plant was also recently announced.
The Mavis Lake Project
International Lithium Corp. in conjunction with Pioneer Resources Limited recently completed their drilling program at the Mavis Lake project in Ontario. Results are expected to be available soon.
Pioneer stated earlier in the project that the first drill hole’s sample appeared to be about 20m thick and estimated to contain around 35% spodumene.
The world’s insatiable demand for high purity lithium products to feed the booming battery market is prompting renewed interest in the exploration and development of spodumene deposits, with a number of projects underway.
FEECO is a leader in advanced thermal processing and agglomeration process solutions and custom equipment. We can supply engineered, robust systems for use in spodumene processing and lithium extraction, including rotary dryers, kilns, coolers, and paddle mixers.
In addition to our custom equipment, we offer a unique testing facility where spodumene and other lithium-bearing materials can be tested at both batch and pilot-scale. For more information on our lithium beneficiation capabilities, contact us today!