We need to find new ways to transform waste into resources. While we already have conventional recycling, where we use discarded products to manufacture lower grade products (such as paper to cardboard), we are now moving to a new generation of innovative recycling where high value products are being manufactured from waste. UNSW’s technique for turning plastic into steel is a good example.

The UNSW Centre for Sustainable Materials Research and Technology (SMaRT@UNSW), which brings together researchers and projects from the Faculties of Science, Engineering, and the Built Environment. SMaRT focuses on developing new recycling technology, processes and materials as well as devising a range of cost-effective and innovative means to re-use waste. Industry relationships have already been formed with a range of companies including Anglo, Blue Scope Steel, CSR, OneSteel, Orica, Rio Tinto, Shinagawa Refractories Australasia, etc in industries as diverse as building, manufacturing, mining, steel and aluminium. Leading scientist Professor Veena Sahajwalla heads the Centre.

Recycling research in all its forms is a strength of UNSW. University researchers don’t just concentrate on developing new methods for recycling but also discovering different ways to add value to waste either by turning them into high value products or into whole new composite materials which can be used by industry.

“Green” steel is set to become a reality with technology that recycles plastic destined for landfills. Invented and developed by Professor Sahajwalla, this innovative technology substitutes the coke and coal used in steel production with polyethylene plastic from shopping bags, soft packaging and some drink containers. By adding the plastic to slag under intense temperatures, Professor Sahajwalla and her team have shown that this plastic actually aids the steel making process by improving furnace efficiency because it sits on top of the molten steel like an insulating blanket. The plastic also has the added advantage of reducing energy consumption. Green steel is set to go global. The UNSW signed a commercialisation deal with a large Australian steel-maker, which will take the technology to more than 300 steel-makers around the world.

The building industry has always been a large contributor to landfill. In breakthrough work, Dr Obada Kayali and Karl Shaw of the UNSW’s Defence Force Academy have developed and manufactured a new type of strong, lightweight house brick from fly ash, a pollutant produced by coal-fired power stations . This is a win for environmental waste management because typically fly ash is buried or dumped in disused mine shafts. The bricks, called Flash Bricks are 28 percent lighter and 24 percent stronger than comparable clay bricks. The scientists have also used the fly ash to develop a building aggregate that is used to make concrete which is 22 percent lighter and 20 percent stronger than standard products on the market.

For more information about UNSW research, please visit the UNSW Research website

Every tonne of mixed waste going into landfill results in the release of 0.9 tonnes of greenhouse gas emissions. Source:
Australian Greenhouse Office (2006) AGO Factors and Methods Workbook. Department of the Environment and Heritage.