Engineers at RMIT University have developed a new method of recycling personal protective equipment (PPE) to make concrete stronger, which could significantly reduce pandemic-generated waste.
Since the start of the COVID-19 pandemic, an estimated 54,000 tonnes of PPE waste has been produced per day across the globe. Around 129 billion disposable face masks are used and discarded around the world every month.
In three separate studies, the RMIT School of Engineering team has investigated the feasibility of recycling three key types of PPE – isolation gowns, face masks and rubber gloves – into concrete.
Published in the journals Case Studies in Construction Materials, Science of the Total Environment and Journal of Cleaner Production, the studies found shredded PPE could increase the strength of concrete by up to 22 per cent and improve resistance to cracking.
Across each study, disposable face masks, rubber gloves and isolation gowns were first shredded then incorporated into concrete at various volumes, between 0.1 per cent and 0.25 per cent.
The research found:
- Rubber gloves increased compressive strength by up to 22 per cent
- Isolation gowns increased resistance to bending stress by up to 21 per cent, compressive strength by 15 per cent and elasticity by 12 per cent
- Face masks increased compressive strength by up to 17 per cent
RMIT’s industry partner, Casafico, is now planning to use these research findings in a field project.
First author on the study, PhD researcher Shannon Kilmartin-Lynch, said the research brings a circular economy approach to the challenge of dealing with healthcare waste.
“We urgently need smart solutions for the ever-growing pile of COVID-19 generated waste – this challenge will remain even after the pandemic is over,” Mr Kilmartin-Lynch said.
“Our research found that incorporating the right amount of shredded PPE could improve the strength and durability of concrete.”
Joint lead author, Dr Rajeev Roychand, said there is great potential for construction industries around the world to play a significant role in transforming this waste into a valuable resource.
“While our research is in the early stages, these promising initial findings are an important step towards the development of effective recycling systems to keep disposable PPE waste out of landfill,” Mr Roychand said.
Corresponding author and research team leader, Professor Jie Li, said PPE waste – both from health care and the general public – was having a significant impact on the environment.
“We have all seen disposable masks littering our streets, but even when this waste is disposed of properly it all ends up in landfill,” Mr Li said.
“With a circular economy approach, we could keep that waste out of landfill, while squeezing the full value out of these materials to create better products. It’s a win on all fronts.”
Mr Li said the next step for the research is to evaluate the potential for mixing the PPE streams, develop practical implementation strategies and work towards field trials.
The RMIT team is keen to collaborate with the healthcare and construction industries to further develop the research.
