December 1, 2005

Greenhouse Innovation wins Excellence Award

A major breakthrough in the way alumina refinery waste is processed – which opens the door to reducing industry greenhouse emissions – has won a top national award.

The new process developed by a team of Alcoa scientists in Western Australia achieves the extraordinary double benefit of making alumina refinery waste potentially re-usable and neutralising a greenhouse gas.
Finding practical uses for new and stockpiled refinery residue – which has ongoing environmental and land use impacts and significant storage costs – is arguably the biggest challenge facing the global alumina industry.
The Residue Carbonation process successfully lowers the alkalinity of the residue (the biggest barrier to its re-use) by bubbling carbon dioxide (an unwanted waste gas) through the mix.
The project is set to become a best practice benchmark for refinery residue treatment and storage in the industry worldwide.
After taking out the major State Engineering Innovation Award in August this year, it last night won Australia’s top Environmental Engineering Award at the 2005 Australian Engineering Excellence Awards.
The project has opened up possibilities for re-using the more benign residue in areas from construction materials and concrete to soil amendments and even fillers for plastics.
It follows years of research and the successful construction, monitoring and detailed evaluation of a major prototype at Alcoa’s Kwinana Refinery.
The carbonation process involves pumping refinery residue through a purpose-built plant where carbon dioxide is bubbled through the mix. This reduces the pH in the residue to levels found naturally in many alkaline soils. 
While carbonation is a process that is always occurring in nature, what makes the project unique and viable is that the research team has also developed ground-breaking new technology to speed up the carbonation process.
Alcoa hopes to implement full scale carbonation of all residue at its Kwinana refinery next year using CO2 piped direct from a neighbouring industry, diverting those emission from the atmosphere.
This is currently going through an approvals process.
Once implemented, the greenhouse benefits at the Kwinana refinery alone would be equivalent to taking up to 12,000 cars off the road.
The team of scientists and engineers that developed the residue carbonation process are part of Alcoa’s elite global research and development department (the Alcoa Technology Delivery Group) based at the Kwinana Refinery.
The research centre invests over $20 million a year and employs 35 scientists, a dozen engineers and more than 30 scientific and other support staff to work on developing processes and equipment to support cleaner production and maximum efficiency at Alcoa refineries worldwide.
The Kwinana team is so highly regarded that in 1996 Alcoa gave them total global responsibility for conducting this research for all of its refineries worldwide (9 refineries in 5 countries).
Today, they are the western world’s largest refining R&D group. They are also the largest gathering of industrial scientists and engineers in WA, and have the largest number of PhD’s working together in WA outside of a university or CSIRO.
Editors Note: High res photos of Alcoa scientists working on the project on site are available on request.