A UNSW project with Sydney Water and Pacific Bio is exploring whether algae that has already helped clean wastewater can be put to work again, this time giving discarded textiles a new life.
Researchers from UNSW Sydney have partnered with Sydney Water and Pacific Bio to investigate how more value can be recovered from algae biomass produced through wastewater treatment.
The early-stage research is exploring whether the biomass can be converted into a binder and combined with underutilised materials such as discarded textiles to create new materials for manufacturing.
Textiles are an initial test case, with the researchers ultimately interested in how the binder could be used across a much wider range of manufacturing applications.
“The opportunity is to look at this algae biomass not as an end product of wastewater treatment, but as the starting point for something else,” says Ms Mariëtte van Bueren, Research Officer in UNSW’s School of Chemistry.
“We're exploring whether the unique properties of algae biomass can be used to create natural binders that could replace fossil fuel-based alternatives across a wide range of manufacturing applications.”
UNSW Associate Professor Anna Wang says, “Developing a new material isn't just about whether the chemistry works.
“You need to understand where the raw materials come from, how they can be processed and whether there's a useful application at the other end. Mariëtte's background in seaweed research, design and economics allows her to consider all those questions together.”
Ms van Bueren's research builds on her Master of Philosophy at UNSW, where she investigated seaweed valorisation under the supervision of Associate Professor Patrick Spicer from UNSW Chemical Engineering and A/Prof. Wang from UNSW’s School of Chemistry.
Giving wastewater algae a second life
The research builds on Sydney Water's innovative algae treatment trial at its Picton Water Resource Recovery Facility. Pacific Bio's RegenAqua technology uses native green macroalgae during the final stage of wastewater treatment to naturally remove nutrients such as nitrogen and phosphorus, improving water quality before it is reused or safely released into local waterways.
As the macroalgae grow, they capture nutrients from the water and convert them into harvestable organic biomass.
That biomass represents an important opportunity beyond water treatment.
The UNSW team are using the biomass to develop a natural binder, similar to a glue or resin, and testing how it performs when combined with discarded textile fibres and other materials.
“Wastewater treatment plants are called Water Resource Recovery Facilities because of the potential to harness the value of nutrients, energy and water supplies - but it is a big change to deliver a circular economy approach. It requires new partners and community support to unlock the value of materials previously considered 'waste'. It also requires science, research and new technologies to manage chemicals from our urban environment,” says Emma James, Recycled Water Lead at Sydney Water.
Creating new pathways for discarded textiles
Textiles provide an important test case for the potential of the new binder. Every year, more than 300,000 tonnes of clothing is either sent to landfill or exported from Australia.
Recycling textiles can be difficult because garments often contain blends of fibres, dyes, buttons and zips.
“A broad range of chemicals are used in textile production processes, including PFAS, glues and dyes,” Ms van Bueren says. “To enable sustainable textile recycling, these should be removed before recirculating the material.”
Rather than requiring perfectly sorted materials, the researchers are investigating processing methods robust enough to work with a wide variety of discarded textiles.
“If we're serious about reducing landfill, we need recycling processes that can deal with the reality of mixed textiles, not just the easy materials. That's the challenge we're trying to solve,” says Ms van Bueren.
“This is a global challenge, and we're trying to contribute our part by identifying and researching different processing methods and pathways to produce the resin and new biocomposite materials.”
One biomass, growing possibilities
The textile application is just one potential pathway for the algae biomass.
Pacific Bio is already exploring applications for RegenAqua biomass across areas including agriculture, energy and building products.
For the UNSW researchers, the next step is to understand what makes the algae-derived binder distinctive and where those properties could be most valuable.
“When you're working with something completely new, the first step is to understand its strengths and weaknesses,” Ms van Bueren says.
“Once we know what it does well, we can identify where it can deliver the greatest value.”
Turning local resources into local products
The research is also exploring how processing could work at a local scale.
Many sources of biomass are available in relatively small quantities or can vary in quality, making them less suited to large, centralised commercial operations. Smaller processing technologies could potentially allow biomass to be converted into useful materials closer to where it is generated.
For councils, utilities and remote communities, that could reduce transport requirements while creating value from locally available resources.
“The vision is for local communities to turn their underutilised materials into something valuable,” says Ms van Bueren.
“Rather than shipping materials across the country, we could create products close to where those materials are generated. It's a simpler way of thinking about recycling and a much more circular one.”
From research to manufacturing
The project is approaching its conclusion, with the researchers aiming to produce a prototype resin and examples demonstrating potential applications.
“By the end of this project, we hope to have a prototype resin that demonstrates the potential of this technology and its applications,” says Ms van Bueren.
“The next step is to secure more funding to work with Sydney Water and a textile industry partner to develop functional products and build the technology needed to transform locally available biomass and other underutilised materials into valuable new resources.”
The project received funding through the UNSW Science Translational Impact Seed Fund, which supports early-stage collaborations between researchers and industry, government, charities, not-for-profits, NGOs and foundations.
Ends
Contact details:
Yolande Hutchinson
Mob; 0420 845 023
