Purer vanadium deposits set to meet demand
Michael Schwartz examines the use of vanadium and its development in the future.
Vanadium is predominantly employed as an additive to steel, although in recent years vanadium phosphates have been promoted as the critical electrolyte in vanadium redox flow batteries (VRFB) and the cathode in a form of lithium-ion battery. One company heavily involved in vanadium mining is Largo Resources, Canada.
Largo’s CEO Mark Smith sets the scene, ‘Over 90% of the vanadium produced in the world is still used in the steel industry and about 50% of that is in the form of rebar. Hence, vanadium is largely involved in the construction and infrastructure industries. However, its use in flow batteries is also growing rapidly right now, with more vanadium used in this sector last year than all prior years combined.
‘According to the vanadium redox battery (VRB) industry forecasts, this sector may need 25,000 – 30,000t/y of vanadium by about 2025. This would be almost 40% of today’s production per year.’
Vanadium is widely distributed globally, but it is difficult to identify and separate. It is estimated that it is found in around 65 minerals as well as fossil fuel deposits. Smith points out that Largo’s ore body is primarily a magnetite structure and that ‘the vast majority of our vanadium is contained in the magnetite’. He adds, ‘By utilising simple magnetic separation techniques, we can recover the valuable vanadium. Indeed, our entire process, starting with mining and ending with V2O5, currently demonstrates a recovery of over 75%.’
Located in Brazil, the Maracás Menchen Mine forms the focus of Largo Resources’ operations. Largo has stated that its vanadium deposit at Maracás Menchen is ‘the highest-grade…yet discovered’, and that it is in an ideal position for VRBs requiring a particularly high quality.
Smith clarifies, ‘Our NI 43-101 resource report shows an average ore grade of 1.17% V2O5, which is over two times higher than the next best vanadium primary mine. Our unit production cost per pound of V2O5 is about $3.50. This places Largo in the top three in terms of low production costs. We produce V2O5, otherwise known as vanadium pentoxide, and we produce it in flake form. By December 2017, we will also be able to produce V2O5 in powder form.’
In addition, Smith says that Largo’s product has been tested by ‘seven battery companies and has demonstrated excellent performance across the board’.
Focusing on Maracás Menchen
Initial construction at Maracás Menchen commenced in June 2012, after finance was achieved. Production commenced in August 2014, and has been at full rate since June 2016.
Maracás Menchen totals 28,587ha and lies in Brazil’s Eastern Bahia State. It is around 250km southwest of Salvador, the capital of Bahia, and 813km northeast of the national capital, Brasilia.
There is good access by road from Salvador to Maracás Menchen via a paved secondary road from the main costal highway in Bahia, and a direct project access road about 50km west of the town of Maracás.
The entire strike length of Maracás Menchen is rich in vanadium and hosts many deposits of VTM, notably at one main and three lesser deposits. Average annual production is estimated at 9,600t of V2O5 equivalent.
The magnetite resource extends over 350m deep, with Largo mining the resource using open pit methods. However, the company confirmed that its resource extends deeper than 350m and that when mining reaches this depth, it will have to evaluate the potential for underground mining.
At present, the company has signed an off-take agreement with Glencore International for all of its V2O5 production for the six years ending in May 2020. In turn, Glencore exports all of the material to the USA and Europe. After purchase by Glencore, the material is transported by truck to the port at Salvador, Brazil, and from there shipped to its next destination.
Another ambitious company wanting to make use of vanadium is the Canada-based VanadiumCorp. Adriaan Bakker, CEO of the company, told Materials World, ‘Close to half the cost of a vanadium battery is attributed to the vanadium itself, needed in high-purity and low-impurity form. No such company exists to provide this stable supply and address this industry bottleneck. Despite expensive electrolyte sourced from the steel industry, positioning the technology at a higher cost to competing technologies, VRFB technology appears to be undergoing mass commercialisation regardless, with a levelised cost over 20 years rivaling lithium batteries. ’The company benefits from a mining-friendly jurisdiction in Quebec, backed by 100% ownership of what is described as two of the purest vanadium deposits in the world. The vanadium is contained in magnetite layers that start at the surface and are therefore easily accessible. In addition, while some magnetite resources contain high silica and oxidation, which are problematic for conventional production, VanadiumCorp does not find these impurities to be a problem, and recovers silica as an added-value product.
At its trial production plant at Boucherville, Quebec, VanadiumCorp is transforming feedstocks such as Vanadiferous TitanoMagnetite (VTM) and vanadium-rich slags and residues into several vanadium – as well as iron and titanium – products.
Green technology also features prominently. In May 2017, the company announced a partnership with Electrochem Technology to develop high-performance vanadium electrolyte for energy storage and a broader spectrum of raw materials. As Bakker has stated, ‘We are applying VanadiumCorp-Electrochem Technology directly to 100%-owned VTM supply and feedstocks to create high-quality energy-storage materials for batteries. Bench-scale testing of our VTM concentrate has yielded consistent recoveries of 95% of metal values from VTM concentrate, which includes electrolytic iron and vanadium chemicals as well as titanium residues – as opposed to 95% loss with conventional methods.’
The current ambition is 1t/month while new equipment for electro-winning is being commissioned – potential clients will be able to assess the quality of the processed vanadium. In the meantime, VanadiumCorp has applied for a US patent, whereby the new technology supersedes conventional processes such as soda ash roasting of the magnetite followed by water leaching.
VanadiumCorp’s flagship Lac Doré VTM project spans 45km2 and comprises an NI 43-101 vanadium resource measurement of 621 million lb V2O5 from VTM concentrate grading 1.08% V2O5. Development was started jointly in 2002 by McKenzie Bay Resources and SOQUEM, who achieved vanadium electrolyte at 99.9% V2O5 for vanadium batteries in Japan. Lac Doré is claimed to possess virtually no impurities and exceptional metallurgical recoveries in its VTM. VanadiumCorp is also involved with V2O3 and Vanadiumcorp Electrolyte.
Transporting vanadium products
One other factor to consider is transportation of vanadium products, typically by rail and ship. On a specific note, vanadium electrolyte is cost-prohibitive to ship as it contains a large amount of water, emphasising the value of local production.
The objective of VanadiumCorp is to become the first and only primary producer of vanadium electrolyte for vanadium batteries. The company is confident it can achieve this, with the most significant resources of high-purity vanadium in North America and its technology aimed at the development of the lowest cost vanadium electrolyte.
Several other companies are involved with vanadium mining, sometimes as a by-product. One is Canada-based U3O8. While this company is focused on uranium, it also extracts vanadium, nickel and phosphate for clean-energy batteries. U3O8 Corp is oriented towards deposits with low production cost potential.
In each of U3O8’s operations, vanadium plays its part in financial viability. At its wholly owned and near-surface Laguna Salada deposit in Argentina, uranium would cost more than its present US$22/lb after allowance has been made for revenue from vanadium.
Another 100%-owned property is the primarily sediment-hosted Berlin uranium deposit, Colombia, where after factoring in the by-products value, uranium would have a production cost of almost zero. Indeed, a preliminary economic assessment shows just how much revenue would be generated not only from vanadium but also from phosphate, nickel, yttrium and neodymium.
For the time being, exploration has defined substantial metals along a 3.5km trend. Drilling is now continuing along a 7.5km strike to the north of the property. U3O8 is also confident that the Berlin project has the potential to generate phosphate for fertilisers from a site close to Colombia’s agricultural heartland.
Besides its conventional use as an additive for steel, vanadium is set to play its part as one of the many commodities crucial for electric vehicles, consumer electronics and energy storage systems for the batteries of the future.