Metso Outotec’s Grate Kiln as step change improvement for the Australian Vanadium Project

The results have been conclusive and confirm that Grate Kiln (GK) technology can be successfully applied to mineral processing that has traditionally utilized different roasting technologies. AVL, engineering and consulting company Wood and Metso Outotec are now working together during the next phases of the project to provide a fully engineered Vanadium process solution that offers much more energy efficiency than the current processes.

Australian Vanadium Limited (AVL) is a Perth-based company bringing the high-grade Australian Vanadium Project in Western Australia into production, targeting clients in the steel and battery markets. In 2019, Metso Outotec was engaged to conduct a pilot testing for the project’s Bankable Feasibility Study because of our world-renowned expertise in Grate Kiln (GK) processing solutions. Traditionally, the GK technology has been used for indurating iron ore pellets, but it has also been successfully applied to similar roasting applications due to its unique ability to improve traditional rotary kiln processes. The GK system is a combination of a rotary kiln, coupled with a travelling grate that is used for pre-processing. The rotary kiln handles the final roasting, while the travelling grate replaces the much less efficient drying and preheating zone of the rotary kiln. Upstream pelletizing offers several benefits to this process, including improved roasting reaction, minimal dusting and reduced build-up of residue within the kiln. It is expected that this will result in a significantly increased vanadium recovery and plant operability over traditional kiln processes.

GK system successfully applied to mineral processing

Under the supervision of AVL and Wood, Metso Outotec has completed a comprehensive pyrometallurgical program for the Australian Vanadium Project, using the pilot pot grate and rotary kiln test rig. Data from this test work was utilized in the final design of the AVL pyrometallurgical circuit, which was included in AVL’s Bankable Feasibility Study released in 2022.

The testing was conducted at Metso Outotec’s Pyro Technology laboratory located in Pennsylvania, USA. The objective was to confirm the results of the initial lab scale tests, performed by AVL and Wood at lab facilities in Australia, and to evaluate and optimize the process parameters such as binder addition, moisture, residence time and the optimal temperature for vanadium conversion. An additional objective was to develop initial roasting and equipment characteristics for the design basis of the commercial plant. The tests have shown that the optimal combination of these parameters can increase vanadium recovery rates from 85-88 % of the traditional process to up to 92-93 % with the GK system using commercial heating profile. Additionally, Metso Outotec has developed and refined a proprietary process model to size the commercial scale plant equipment.

Results of the project have demonstrated that Metso Outotec’s GK system can be successfully applied to mineral processing that has traditionally utilized different roasting technologies. Vanadium conversion requires relatively high temperatures and long residence times, but Metso Outotec has been able to show that the GK technology can be applied to these unique processing requirements. In the case of vanadium, the GK system has demonstrated huge recovery improvements. This is a successful example of applying existing low-risk technologies to improve mineral processing flowsheets.

Committed to successful collaboration

AVL, Wood and Metso Outotec are committed to working together during the next phases of the project to provide a fully engineered Vanadium process solution that offers much more energy efficiency than the current processes, while still improving Vanadium recovery and operability.

The project’s front end engineering design is expected to begin soon and Metso Outotec and AVL will continue their collaboration to finalize the ultimate design. The goal is to reduce equipment size, improve heat recovery and further optimize the pyrometallurgical operation as part of the final design.

The partnership between AVL, Wood and Metso Outotec has already offered unique opportunities for technical collaboration and delivered a low-risk process, significant improvement in project economic and an improved carbon footprint. The next phases of the project collaboration, including Front end engineering design, construction and commissioning will assure that the Australian Vanadium Project will deliver world-leading results.

Interesting facts about Vanadium - Energy storage as driver to boost the Vanadium market

Steel production accounts for more than 90% of Vanadium consumption, due to Vanadium’s unique micro-alloy effects and superior hardening properties. The use of Vanadium in energy storage technology currently occupies only 2% of total consumption. This share will rapidly increase as the range of applications and market presence of Vanadium based energy storage technology increases worldwide. While lithium-ion batteries are primarily designed as smaller cells for use in the automotive market, Vanadium-based energy storage systems are predestinated for commercial, industrial, and municipal uses from the kilowatt to gigawatt range. The VRFB, developed for large energy storage requirements, stores energy via electrolytes. Currently, more than 100 storage systems with capacities up to 400MWh have been installed worldwide. A recent report by Guidehouse Insights predicted that global annual deployments of VRFBs will reach approximately 32.8GWh in 2031. This potential for growth in the energy sector, coupled with Vanadium’s use in steel for the defense sector highlights Vanadium’s role as a strategic raw material in the USA, Australia, and around the world. A solid and secure market future is therefore emerging for producers of Vanadium.