Concrete outcomes
The built world is set in concrete, and increasingly, in energy- intensive quick-drying concrete. Monash University expertise is helping find an alternative that is kinder on the environment.
It has evolved from the drive for economic efficiency in an industry where time means money. Concrete pours on major construction sites must reach high strength quickly, allowing work to continue the next day.
The price of this "one-day" efficiency is paid by the environment. Every tonne of this rapidly-setting "Portland" cement creates a tonne of carbon dioxide (CO2) through the enormous amounts of energy required to heat the raw materials in a kiln.
Researchers at Monash and a leading science and technology institute, the Indian Institute of Technology Bombay (IITB) in Mumbai, are looking to nature for clues in their quest to create "greener" cement.
Their search is one of 36 research projects being pursued in a joint venture between Monash and IITB.
Dr Frank Collins from the Faculty of Engineering is leading the Melbourne team involved in the concrete project, in partnership with Professor D N Singh, who will coordinate a Mumbai-based team. Research will be carried out by PhD students simultaneously enrolled at both institutions.
Dr Collins said progress towards greener cement had already been made by blending cement with industrial by-products like the steel smelting by-product slag and also with fly ash, one of the residues generated in the combustion of coal.
He said while blended cements had better long-term strength, they had slower hardening times, making them less attractive in mainstream construction.
"We can accelerate early age strength with chemicals, but they are very caustic -- you wouldn't want to put your hand in it, you'd lose your skin -- so beyond the laboratory, you couldn't really use them," Dr Collins said.
He said the solution was to find a natural material to react with the slag or fly-ash, increasing the strength as well as filling air cavities in the concrete.
"You would just go to your hardware store and buy an accelerator bag to add to the blended cement. The add mixture would have a biopolymer in there that would be much easier for the industry to deal with," Dr Collins said.
He described the project as highly original and said "on paper" the prospect of finding such a catalyst looked very promising.
Some of the other IITB-Monash Research Academy projects will have a community development focus, others economic. Some, like the cement project, will have both. Work will focus on themes in areas of mutual interest to Australia and India including water, clean energy, biotechnology and stem cell research.
Students will carry out PhD projects co-supervised by academics from IITB and Monash. They are offered attractive scholarships and on completion receive a dual-badged PhD degree. The work involves a minimum six-month study period in Australia.
Some of the other joint venture projects underway or seeking candidates are:
- A project to study the effects of carbon dioxide injection on the behaviour of coal in uneconomic coal seams, a little-investigated aspect of carbon capture and storage from power stations.
- A project to improve understanding of artificially engineered geothermal reservoirs, enhancing the permeability of hot rocks and improving their usefulness as generators of steam for electricity.
- A project to protect ground water resources from pollution by improving barrier systems in landfill.
Construction of the Academy in Mumbai is expected to start in November 2008. Once fully operational, the centre expects to support about 400 research projects a year.
Visit the IITB-Monash Research Academy website.