An Indian-Australian scientist who has been looking for ways to transform waste into something useful, said here on Saturday that non-metallic waste can be turned into new economic opportunity.
"We can either consider non-metallic waste as an environmental burden or turn it into a brand new economic opportunity," Veena Sahajwalla, Director at the Centre for Sustainable Materials Research and Technology at the University of New South Wales in Australia, said.
Sahajwalla, who invented Polymer Injection Technology (PIT) that can be used to recycle end-of-life rubber tyres to replace coal and coke in making a green steel, was speaking at "Scrap Recycling Conference – Emerging Markets".
The two-day event that addressed the need to develop the scrap recycling industry in India saw participation by over 280 delegates from the scrap and steel industry.
"Green steel could be a potential solution deal with the growing problem of disposal of waste tyres globally," Sahajwalla added.
The PIT or "green steel" technology introduces a simple modification into the conventional manufacturing process for steel precisely and controls the injection of granulated waste tyres in conventional electric arc furnace (EAF) steel making, partially replacing non-renewable coke.
Waste tyres, like coke, are good sources of hydrocarbons. This means they can be usefully transformed in EAF steel making, as long as the process of injecting them into the furnace is precisely calibrated.
However, though modern tyres are fundamentally rubber products, they are a complex mix of natural and synthetic rubbers, and various structural reinforcing elements such as metals and chemical additives, which makes the recycling process more complicated from the traditional methods.
This complex nature of wastes has also led to stockpiling, dumping and diversion to landfill, exposing people to environmental and health risks.
"So from the traditional reduce, recycle and reuse one has to move towards reforming. It’s the transformation of waste to higher value products," Sahajwalla noted.
In addition, the waste stocks are full of materials that contain valuable elements like carbon, hydrogen, silicon and metals that we would otherwise source from virgin raw materials.
The technology may not only help control pollution but also open several avenues for metal and scrap processors in India, Sahajwalla said.