Are glass stockpiles coming to and end? Maybe. Australian researchers have found a way to transform used glass into a premium building material.
Australia generates almost 70 million tonnes of waste per year of which 1.4 million tonnes is glass packaging such as beer bottles and food containers. The state of New South Wales alone consumes almost half a million tonnes of glass products.
At the moment, some 57% of glass waste is recycled. During the last couple of years it has more expensive to recycle glass than to import it so many companies choose to stockpile the material.
New polymer concrete
The recycling sector could be boosted by a new project at Deakin University. An R&D trial proved that ground recycled glass can replace sand to create a ‘polymer concrete’. This type of high strength, water-resistant concrete is popular in today’s construction industry. It is especially used for industrial flooring in areas subject to heavy traffic such as airports.
Stronger and cheaper
Senior engineering lecturer Dr Riyadh Al-Ameri says the addition of glass results in a stronger product that is less costly to produce. This is an interesting discovery for a sector that represents 6% of global gross domestic product worldwide.
Mined sand requires extensive washing and grading before it is added to the mix of aggregate, cement and water. ‘Finding an alternative to sand makes good economic sense,’ Al-Ameri argues. Deakin’s concept has even more appeal because of predicted shortages of virgin sand in the medium term.
‘Our research provides the evidence the construction industry needs to see the potential of glass as a substitute for sand when making polymer concrete and, potentially, concrete,’ Al-Ameri concludes. He was named one of the ‘top 30 engineers of Australia 2018’ by non-profit industry organisation Engineers Australia.
As a next step, Deakin’s research crew will explore substitutes for the aggregate in polymer concrete while optimising the substitution rate. The volume of glass reaching end-of-life will increase in future with research firm Statista projecting the glass packaging market will be worth upwards of US$ 70 billion (EUR 62 billion) by 2022.
Meanwhile, the EU’s mature recycling mindset could make an attractive market for Deakin’s glass recycling solution. More than 10 million tonnes of post-consumer glass bottles and jars are recycled every year, representing a recycling rate of almost 75%, according to the European Container Glass Federation (FEVE).