ARENA grants Rio Tinto and Sumitomo $22.1M to trial hydrogen calcination tech

In Australia, the Australian Renewable Energy Agency (ARENA) has announced A$32.1 million for Rio Tinto and Sumitomo Corporation to trial hydrogen calcination technology at the Yarwun Alumina Refinery in Gladstone, Queensland.

The A$111.1 million Rio Tinto and Sumitomo Corporation Yarwun Hydrogen Calcination Pilot Demonstration Program’ will be the first-of-its-kind deployment of hydrogen calcination in the world.

The project is intended to reduce emissions in alumina refining, which currently contributes roughly three per cent of Australia’s greenhouse gas emissions. The project will consist of a 2.5 MW on site electrolyser to supply hydrogen and a retrofit of one of the refinery’s calciners to operate with a hydrogen burner.

Sumitomo Corporation will own and operate the electrolyser at Rio Tinto’s Yarwun site and supply the hydrogen to Rio Tinto directly. The electrolyser will have a production capacity of more than 250 tonnes of hydrogen annually. Rio Tinto will conduct a series of tests of the hydrogen calciner under differing operating conditions to validate suitability and performance.

Calciners, which use high temperatures to extract chemically bound water from alumina crystals, traditionally use fossil fuels for process heat and contribute roughly 30% of emissions from alumina refining. Hydrogen calcination also produces high purity steam, which unlike contaminated steam from fossil fuel calcination, can be recycled for use in other stages of the refining process.

If successful, the project will demonstrate the viability of hydrogen calcination and pave the way for adoption at scale across other alumina refineries. The demonstration follows a successful feasibility study conducted by Rio Tinto, which ARENA supported with a A$580,000 grant in 2021.