Metals industry

A win for circular economy, not solely for down under

Tenova was awarded a contract by Latrobe Magnesium Limited (LMG) for the supply of the Magnesium Oxide (MgO) production plant at the Latrobe Valley (Victoria), Australia, using a world-first process to produce magnesia metal from fly ash.

#6_November 2022

Tenova, a leading developer and provider of sustainable solutions for the green transition of the metals industry, was awarded a contract by Latrobe Magnesium Limited (LMG), a company based in Australia. The scope of work is the engineering, supply and supervision of the Magnesium Oxide (MgO) production plant at the Latrobe Valley, Victoria, Australia, a demonstration plant using a world-first process of combined hydrometallurgical/thermal reduction.

Thanks to this process, the plant will harvest magnesium metal from a fly ash resource – a hazardous waste material from brown coal power generation. The project is at the forefront of circular economy and environmental sustainability as it converts nearly 100% of the resource into valuable commodities. The released CO2 emissions are approximately 50% less than comparable magnesium production plants. “The project is of paramount importance for Tenova, because it opens positive future perspectives and is in line with our effort towards achieving a sustainable production”, explains Gregor Kappacher, Branch Manager at Tenova Austria. “The long-term, international experience of our technologists and continuous further development of the spray roasting process was a decisive factor in realizing this project together with Latrobe Magnesium (LMG).”

Spray roasting is a commonly utilized technology in the steel industry that was adapted for use in LMG flowsheet for extracting and producing magnesium metal. The technology also provides for regeneration of an important reagent, enhancing the cost effectiveness of LMG’s process. Tenova is an established provider of this technology, and years ago the company tried to enter the magnesium industry with some success, but the market had no demand for this mineral.

Nowadays the demand for magnesium metal worldwide continues to grow strong, as the material specification has the best strength-to-weight ratio of all common metals and is increasingly used in the manufacture in automotive industry, computers, mobile phones and power tools.

The project’s advantages in terms of sustainability and circular economy are two-fold: capturing environmentally harmful residues and recycling them in the production of Magnesium, regarded by the metallurgical industry as an upcoming metal which is being increasingly used by the automotive industry while tests are being performed for its use in the battery industry.

“It is a light weight metal with an excellent weight-to-strength ratio. At times when everybody is thinking about CO2 reduction, we understand that magnesium alloys can be used to produce lighter-weight cars, which in turn would produce lesser emissions,” notes Kappacher.

“It also has advantages as an alloy,” he adds, “the industry is also moving forward using aluminum, which we know is a soft metal. But if we add magnesium, then you can have the combination of a light metal with higher strength. The production of magnesium ion battery has very similar advantages, as magnesium is cheaper, light-weight and safer, besides being fully recyclable.”

And yet there’s one more positive aspect regarding the use of this new technology: while magnesium demand is increasing at a global level, at the moment China produces almost 86% of the world’s magnesium. As the country itself is increasing its internal demand for this mineral – on environmental concerns as well –producers worldwide are attempting to reduce transportation costs while avoiding disruptions in the supply chain, many countries are considering the reshoring of magnesium production.

“More importantly,” highlights Kappacher, “this is a fully scalable project that meets both the need to reduce CO2 emissions and to continue to look for more environmental-friendly steels by recycling captured emissions.”

As part of the first phase of the project, Tenova’s scope will include a magnesium oxide (MgO) plant, with the latest state of the art spray roaster technology, with a production capacity of 300 kg/h. The demonstration plant will initially have capacity of 1,000 tons of magnesium (Mg) metal per year, and in the second stage, LMG intends to develop a commercial scale operation with an envisaged production capacity in the range of 10,000 to 40,000 tons per annum of magnesium metal.