Research to save millions of tonnes of glass from landfill

A new process turning waste glass into every day products could save tens of millions of tonnes of glass from going to landfill every year.

University of Queensland (UQ) PhD candidate Rhys Pirie and Professor Damien Batstone have developed a method to extract liquid silicate from waste glass, which can be used to make thousands of products, from concrete sealers and fertilisers to detergents and toothpaste.

“We estimate the process is more than 50% cheaper than conventional ways of producing silicate,” Pirie said. “It requires less energy, raw materials and capital, and that’s before you consider the reduced social and economic costs compared to landfilling material.”

Co-funded by the Cotton Research and Development Corporation and Department of Agriculture and Water Resources, UQ’s method leaves behind little waste, with nearly all of the glass being turned into saleable products.

Pirie began exploring the possibilities of glass recycling after speaking with Professor Batstone, a specialist in converting waste into high-value products, from UQ’s Advanced Water Management Centre.

Pirie commented, “The transition towards circular economies is a movement which is gaining momentum and something I’ve always been interested in. My PhD has highlighted how we need to make use of both the raw materials in ‘waste’ streams and the energy embodied in them during manufacture.”

For the remainder of his PhD, Pirie is looking at ways in which waste glass could also be used to create a low-cost silicon-based additive to increase fertiliser efficiency.

UniQuest, UQ’s commercialisation company, has filed a patent covering the process and is now seeking commercial partners.

Image courtesy of University of Queensland.