Environmental Health & Safety

Australia Aims to Cut Emissions with Rocks

Method transforms carbon dioxide emissions into carbonate rock.

By Seán Ottewell, editor at large

A research pilot plant planned for the University of Newcastle (UoN), New South Wales, Australia, will trial a new technology that transforms captured carbon dioxide emissions into carbonate rock. The material has potential use in the construction industry as bricks and paving stones for green building projects.

Material has potential use as bricks and paving stones for green building projects.


Mineral Carbonation International (MCi), a partnership between the university's commercial arm Newcastle Innovation; the GreenMag Group, Newcastle; and Orica, Victoria, has received funding to establish the pilot plant and undertake further fundamental and industrial research into mineral carbonation technology.

Following six years of R&D by MCi, Australia is leading the development of this novel method for permanently and safely disposing of carbon emissions from fossil fuel electricity generators and other industrial processes, effectively closing the loop on carbon and preventing it from accumulating in the atmosphere.

MCi will conduct the project over four years using a budget of A$9.12 million ($8.42 million), with funding of A$3.04 million ($2.81 million) each from the Australian and New South Wales governments and Orica.

Orica CEO Ian Smith says the company saw this project as a major sustainability commitment. Orica already is capturing some of the carbon dioxide emissions at its Kooragang Island manufacturing facility in Newcastle. In fact, the company reported in 2012 that its global carbon abatement activities had already resulted in the equivalent of removing 150,000 cars from the road. However, with no suitable disposal technology, it's looking for solutions appropriate for itself and industry.

The process involves taking a basic rock such as serpentinite, and crushing, heating and mixing it with water, then pressurizing with carbon dioxide to speed up the natural carbonation reaction. This, in turn, forms stable magnesium carbonate powder and sand.

Mineral carbonation technology mimics and accelerates the Earth's own carbon sink mechanism by combining carbon dioxide with low grade minerals to make inert carbonates, which are similar to common baking soda.

"The technology is proven in the lab and we now want to see if we can scale it to reduce the cost to be in line with a future carbon price," MCi CEO Marcus St. John Dawe says. "The major difference between this and geosequestration is that we are permanently transforming carbon dioxide, not just storing it underground. It's ideal for New South Wales where there is an abundance of low-grade mineral deposits that fit our environmental standards and don't compete with farming land. The potential exists to create many new jobs in a cleaner energy industry," he adds.

However, cost remains an important issue. A 2005 IPCC study into the potential for mineral carbonation found that a power plant with a full carbon capture and storage system using mineral carbonation would require anywhere from 60–180% more energy than the power plant alone.

St. John Dawe, however, notes that this report summarizes earlier work by various researchers and didn't consider the MCi approach of direct thermal activation of serpentinite, which is much more energy efficient.

"While there will always be a penalty in capturing and securing carbon dioxide as opposed to simply venting it to the atmosphere, our research is aimed at reducing this penalty as much as possible," he notes.

A multi-disciplinary team of researchers, chemical and industrial engineers led by Orica senior research associate Dr. Geoff Brent and professors Bogdan Dlugogorski and Eric Kennedy at the Priority Research Center for Energy at UoN are conducting the project.

Brent says mineral carbonation represents an exciting opportunity to develop a secure and potentially large-scale approach for carbon emissions while producing valuable byproducts. He believes Orica has a strong incentive to invest in solutions that could deliver carbon reductions on a commercially and environmentally sustainable basis.

"The Earth's natural mineral carbonation system is very slow," says Kennedy. "Our challenge is to speed up that process to prevent carbon dioxide emissions accumulating in the air in a cost-effective way."

The pilot plant will be built at the UoN's Newcastle Institute for Energy & Resources and is expected to be operational by 2017.



ottewell.jpgSeán Ottewell is Chemical Processing's editor at large. You can e-mail him at sottewell@putman.net.