Wastewater solution offers infinite potential

For most people, doing laundry is a dull and repetitive chore, but for NSW hospitals, it’s a high-stakes task with significant implications for patient health — and the environment.

Researchers at the UTS Centre for Technology in Water and Wastewater (CTWW) are working in partnership with water solutions company Infinite Water to deliver a practical, scalable and energy efficient wastewater recycling system for use in hospital laundries.

Supported by funding from the NSW Chief Scientist’s Water Purification Challenge, the system is being developed for HealthShare, a government agency that provides laundry services for NSW hospitals.

It will respond to a series of well-defined challenges facing hospital laundries: capturing microplastics that are present in the wastewater, removing pathogens and organic matter from hospital bedding and clothing to prepare the water for re-use, and delivering more energy efficient treatment processes.

“Incorporating our research breakthrough in microplastic monitoring with state-of-the-art filtration technology, this system is a bespoke solution for commercial laundries to achieve environmental sustainability and cost saving at the same time,” says CTWW Director Professor Long Nghiem, who is leading the UTS team in this collaborative project.

Towards cleaner laundry water

The system is comprised of three parts: a silicon carbide membrane, a catalytic advanced oxidation filter, and a UTS-designed inline microfibre detection system. The membrane acts as a filter for the laundry wastewater, while the oxidation filter has catalytic functionality that will remove organic matter and de-activate any pathogens that are present in the water.

UTS’s microfibre detection system will also be used to accurately monitor the amount of microplastics captured and removed by the technology. In the hospital setting, these microfibres are shed from sheets, gowns and other hospital items that are constructed from synthetic materials.

With every millilitre of wastewater containing thousands of microplastics, which are invisible but can threaten aquatic life, it’s a challenge that demands urgent solutions.

“HealthShare has seven locations across NSW where they wash between 10 and 40 tonnes of clothing a day,” says Professor Nghiem.

“Without appropriate treatment, a huge amount of plastic microfibres from laundry wastewater will end in the aquatic environment and we know the potential toxicity that they cause to wildlife.

“The system can pay for itself in two or three years from cost savings through water reuse while stopping the flow of microplastics to the natural world.”

An energy efficient solution

As well as capturing the variety of nasties that lurk in laundry wastewater, the researchers are also focused on lowering the environmental impact of the water recycling process.

To meet quality standards, water for hospital laundry is heated to about 50 degrees Celsius. While cooling the water prior to filtering it would make it simpler to treat, the system will work with hot water, thereby reducing the amount of energy required to re-heat the water once it’s returned to the laundry system.

The technology allows us to actually treat the water immediately after it comes out of the washing machine. As soon as it’s clean, we’re sending it back to the front end of the washing machine for re-use.
- Professor Long Nghiem

The potential of this research has been recognised by more than $1 million in funding from the NSW Government; once completed, the system will be implemented at a HealthShare laundry, with plans for more widespread rollout to other commercial laundries down the track.

As well as solving pressing problems for hospital laundries, the research also holds promise for application in a range of other sectors that use commercial laundry facilities, including textiles, packaging and consumer goods.

Past successes, future opportunities

Together, the CTWW and Infinite Water teams have developed a strong track record delivering innovative water projects in Australia and beyond. These include a recent initiative to build and implement a small-scale water treatment plant to remove arsenic from groundwater at a school in Vietnam.

In fact, the partnership has been so successful that the Infinite Water Research & Development team recruits many graduates from the UTS PhD program. Now, the collaborators are considering co-locating some of their activities at a new CTWW laboratory that’s currently under construction at the UTS Tech Lab facility in Botany.

“Working with UTS on these collaborative projects is a big part of our strategic goal to be a leader in water innovation,” says Agatha Walczuk, Executive Director and Co-founder of Infinite Water.

“Their students can step from the UTS lab into working with us on real commercial projects, and we get the benefit of very smart, dedicated people.  

“Together, all these bright minds develop novel solutions that often have a significant impact on the water industry.”