Australians with kidney failure could soon be helping prevent concrete cancer, thanks to ground-breaking Victorian research. The researchers are trialling the use of plastic medical waste from dialysis treatments to create stronger, more durable and corrosion-resistant concrete.
A team from Deakin University’s School of Engineering is currently experimenting with the use of the shredded waste as a concrete additive. The initial results are promising, according to project leader and senior structural engineering lecturer, Dr Riyadh Al-Ameri.
“Concrete can crack and damage the internal bond, which can then lead to water penetration and corrosion of the steel bars, critical for providing the strength and integrity of concrete structures,” he says.
During initial testing, Dr Al-Ameri’s team added shredded plastic dialysis waste to a concrete mix at concentrations of 0.5 per cent and one per cent by weight of concrete, with results showing this made a more durable and significantly more water-proof product.
The researchers are trialling the use of plastic medical waste from dialysis treatments to create stronger, more durable and corrosion-resistant concrete.
“The 30 per cent decrease in water absorption we found is significant and would be expected to improve resistance of concrete to corrosion,” Dr Al-Ameri says.
The project is a collaboration between Dr Al-Ameri and nephrologists Dr Katherine Barraclough from the Royal Melbourne Hospital and Professor John Agar from Barwon Health’s University Hospital Geelong. The specialists approached the university looking for a solution to their major plastic waste issue.
Each dialysis treatment creates between one and three kilograms of plastic waste. To put that in perspective, there are more than 12,000 Australians on dialysis. That results, as Dr Barraclough says, in about 5,100 tonnes of plastic waste a year. The reason the procedure generates such a large volume of plastic refuse is the haemodialysis process involves making a circuit where blood is pumped from the patient’s bloodstream through a machine that takes out toxins and excess water and then returns the clean blood into the patient.
“For safety reasons, both the tubes that carry the blood and the dialyser (the part of the machine that cleans the blood) are made of plastic designed for single use only,” Dr Barraclough says. “Because the waste is potentially infectious, it must be either burnt or sterilised before being thrown away. This not only costs a lot of money, but also causes significant harm to the environment.
“With increasing numbers of people requiring dialysis in Australia and worldwide, we need to work out ways to reduce the costs of care delivery, as well as play our part in ensuring a healthy environment for future generations.”
The project has attracted funding from an industry partner Fresenius Medical Care, a global provider of dialysis products and services.
The engineering team are now looking to conduct more rigorous testing to see if the new concrete mix can stand up to harsh conditions. The university’s concrete lab has accelerated weather corrosion tanks that will be used to simulate a marine environment.
The engineering team are now looking to conduct more rigorous testing to see if the new concrete mix can stand up to harsh conditions.
“One month in the lab is equivalent to approximately one year outside, so we can observe the behaviour of the material quickly and efficiently,” Dr Al-Ameri says. “Wet and dry cycles can have a big impact on the durability of the concrete, and sea water has chloride, which is very harmful to both concrete and steel reinforcement.”
The ultimate goal is finding innovations that will help concrete construction better survive in marine environments and coastal areas that are exposed to humidity.
“If we are able to facilitate production of new types of concrete that will offer better protection, give structures longer life, and better performance, as well as help recycle plastic waste, that will be a great achievement,” Dr Al-Ameri says.