Australian scientists have developed a technique to use waste plastic in steel making, a process that could have implications for recycling scrap metal that accounts for 40 per cent of steel production.

Professor Veena Sahajwalla of the University of New South Wales has won a prestigious Australian science award for what she calls “the hottest research in town”, which she hopes will turn an environmental headache into a valuable resource, a Reuters report said.
Under the process, waste plastics are fed into electric steel-making furnaces as an alternative source of carbon and heated to super-hot temperatures of 1,600 degrees Celsius (2,912 degrees Fahrenheit).
Sahajwalla said many waste plastics, from shopping bags to dishwashing liquid containers and drink bottles, contain high enough levels of carbon to be useful in steel making.
Carbon is used to add strength to steel. The higher the carbon content, the stronger but less ductile it is.
“The carbon component that’s present inside plastic is what we’re after and, at those high temperatures, we’re able to react it in a way that we’re able to use that carbon that’s locked in the plastics. Typically you would add coal and coke,” she said.
Sahajwalla said her process did not replace all of the coal and coke, but still used a mix of plastic and coal.
“If you’ve got a whole lot of waste plastics that end up in landfill, not just in Australia but across the world, then it’s really coming up with alternative technology for its disposal which is environmentally friendly,” Sahajwalla said.