Mining

Latrobe Magnesium prepares for start of demonstration plant’s major construction phase

Go to Imelda Cotton author's page
By Imelda Cotton - 
Latrobe Magnesium LMG ASX demonstration plant construction Victoria Latrobe Valley

Once the 1,000tpa magnesium demonstration plant has successfully operated, Latrobe will expand capacity to 10,000tpa.

Copied

Early works for Latrobe Magnesium’s (ASX: LMG) 1,000 tonnes per annum magnesium demonstration plant in Victoria’s Latrobe Valley have paved the way for remediation and preparation of the site for major construction works.

The project’s critical long lead items – including the plant’s spray roaster and reduction furnace – have been issued for tender and the company is focused on finalising several design and engineering process milestones including the preparation of construction packages for tendering.

Engineering procurement and construction contractor Mincore is progressing specifications and datasheets for remaining equipment needing to be tendered including a multi-effect evaporator, briquetting, filtration and thickening systems.

Mincore has been onsite to evaluate the completed early works and begin preparations for the construction of the plant.

Latrobe has awarded a tender for the administration building, security gatehouse and carpark and mobilisation of the chosen contractor is underway.

Minor project construction has commenced with major stages set to begin in the second half of the year.

In its December half-yearly report, Latrobe announced it had reduced the size of the demonstration plant from 3,000tpa to 1,000tpa to curb capital expenditure costs and reduce the time to construct.

World-first process

Latrobe is building its $45 million magnesium demonstration plant using a world-first patented hydrometallurgy/thermal reduction process to convert industrial fly ash (currently a waste stream from the Yallourn power station) to magnesium metal, supplementary cementitious material, amorphous silica, char and iron oxide.

In October 2019, the company signed an agreement with EnergyAustralia Yallourn to secure ash supply to the plant for the next 10 years.

Last March, EnergyAustralia announced it would be closing the power station in mid-2028.

Latrobe believes sufficient fly ash can be mined from Yallourn’s current ash repository and production volumes over the next seven years to provide feedstock for a 20,000tpa magnesium plant for a period of 25 years.

Once it has successfully operated its demonstration plant, Latrobe said it would expand capacity to 10,000tpa and hopes the nearby Hazelwood power station could become an option for feedstock.

Magnesium extraction

The extraction of magnesium from brown coal fly ash is a new industrial process whereby magnesium is dissolved from the ash to recover solid magnesium oxide.

This is then reduced to magnesium metal using a high-temperature process, with the remaining material able to be utilised as a cement substitute in the construction industry.

The process is expected to achieve a 62% reduction in carbon emissions compared to conventional Chinese industry performance.

This is due to the lower concentration of carbonates in the fly ash, compared with normal dolomite ore feedstock as well as the production of key consumable ferrosilicon using hydroelectricity.