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Wonderful Waste

Wonderful Waste with Veena Sahajwalla

Professor Veena Sahajwalla has many impressive titles to her name; internationally recognised scientist, materials engineer, inventor of “green steel Polymer Injection Technology”, scientia professor at UNSW, and not to mention, 2022 NSW Australian of the Year.

Ever since she was a kid in Mumbai, she had always been curious about recycling and the environment, questioning what scrap materials collected every day from her home were used for. Now, she’s still equally curious about the remanufacturing processes she can develop in her microfactories, how she can better educate other people in the area of recycling, and more importantly, what “waste products” she can reuse in her everyday life.

NTS caught up with Veena to talk about what ignited her passion for recycling, what projects she’s currently working on, and her advice for Australians regarding waste in the environment.

NTS: Tell us a bit about yourself and what led you to where you are now.

Veena: I’m Veena Sahajwalla, a professor at the University of New South Wales and director of the SMaRT Centre here. I love recycling, but I think, equally importantly, love to see so many incredibly amazing people that I get to work with every day here at the SMaRT Centre.

What we’re really passionate about is how we see the world of recycling and how we recycle waste, but more importantly, how we combine that with remanufacturing to be an integral part of the solution for our environment.

Veena Sahajwalla

Right from the early days of my childhood when I grew up in Mumbai, India, I was very curious about a daily system where people would come around and collect your waste newspaper and glass bottles. In return, they’d give you a little steel spoon. It was fascinating to me because they had figured out how much of this old newspaper they needed, but they also wanted to give back something that was useful. That, as a kid, made me start to understand the importance of materials and the fact that nothing was wasted.

NTS: How did that impact your education and your career?

V: It made me passionate about material science and the multifaceted nature of what science, engineering, and technology bring to the planet. That’s why I chose to pursue my passion for materials, science, and engineering in my undergraduate and postgraduate degrees, taking it into various industrial applications.

NTS: Talk to us more about your incredible invention of “green steel”.

V: Steel is such a versatile material, especially when we think about how many different ways in which we use steel. Our green steel Polymer Injection Technology (PIT) is about bringing in sustainable alternatives to coal and coke, such as rubber, which contains carbon that’s essential for steelmaking and hydrogen. We certainly want to make sure that, as the world’s most recycled material, we want to capture every bit of steel that comes off various applications and have it ready for its next life, no matter how difficult that form of steel might be.

Traditionally, when we think about making steel through an integrated system where you are reliant on coal and coke, the carbon footprint is closer to about two or two and a half tonnes of carbon released per tonne of metal produced.

Compare that to what we do, which is using an electric arc furnace for scrap steel. We’ve had a reduction in terms of reducing our carbon footprint and enhanced efficiency due to our PIT.

This is important because to decarbonise our metal production and make more green steel, we need to bring in more recycled steel into our economy. We should be targeting more steel produced through recycling, so that we can bring in more renewables, both in terms of energy as well as eliminating coal and coke.

The most exciting part about this is that green steel could be used for all kinds of different various industrial applications, and even for buildings. As the world starts to make all kinds of products from green steel, there will be the desire to look at how we bring in more green steel into production and into manufacturing, allowing us to deliver a greener planet.

NTS: What remanufacturing process are you working on at the moment?

V: As we know, fast fashion and fast furniture generate huge amounts of waste textiles. We need to find solutions that go beyond the whole thinking around landfill. We can’t assume that just because something is not wearable or is broken the first option is to send it to landfill. There are usable materials there, like fabric, wood waste, metal waste, and so on.

At our microfactorie, that’s exactly what we are doing: creating the ability to link together our waste and seeing it as a resource, not as waste but as part of materials that can go into our supply chains and be remanufactured. Our green ceramic products are made from waste textiles and waste glass, and the purpose of that is to deliver environmental outcomes for our communities.

If we can set up multiple pathways through which we can recycle, reform, and remanufacture all kinds of high-quality products, it then allows our communities and our societies to use these products that have highly engineered properties. We’re creating this laterally integrated system where waste could come from our homes and our offices to become part of the economy.

Veena Sahajwalla

NTS: What other processes are you working on in your microfactorie?

V: There are a lot of different materials, whether metals or plastics or glass, in our electronic devices and systems. As technologies advance and as new devices come in, we’re generating a lot of electronic waste, or e-waste, and it’s actually the world’s fastest-growing waste.

By bringing that plastic waste into our microfactories, we create plastic filaments and use them for 3D printing completely different products. We’ve taken the electronics and shown that they can be manufactured and remanufactured into clamps, which then become a component in a construction project. We’re taking different kinds of products that we need in our society, but making them from waste that comes from a whole different sector.

NTS: What are your hopes for the future and for the SMaRT Centre?

V: Firstly, I think about the micro-recycling system where thermal transformations allow you to separate the metallic and the non-metallic parts. This will be a world first because we’re not talking about traditional smelting, where all the materials come apart — this is us simply isolating different kinds of materials.

We’re super excited that our new microfactorie, previously located in Nowra and now at RenewIT in Sydneylocated in Nowra, NSW, is allowing us to produce our filaments from waste plastics, showing us we can increase our capacity. More and more plastic filaments for 3D printing can be made from 100% recycled plastics. That means our communities, our school kids, and our manufacturers, will all be able to utilise plastic filaments made from recycled plastics. It’s a great way to show that all of those waste plastics that we thought were difficult to recycle are now being recycled, reformed, and used for remanufacturing.

NTS: How would you describe waste in Australia and any ideas on how we can improve as Australians?

V: As a society in Australia, we can do better at sorting out waste.

Our role should be very much first and foremost asking ourselves, how can we do more? How can we sort and channel these products to the right destination?

Veena Sahajwalla

Local governments are actually great places for us to connect with, because not only are they providing a council pick-up day or a drop-off day, but they also have programs in which they do community activities. When you are involved in community-based activities, you actually have the opportunity to learn so much.

If there are local businesses or a local council offering recycling services, we need to step up and say, let’s do our part to provide old non-functioning products that go through our local council into a microfactorie. As citizens, we can play such an important role in making sure that we are actually supplying these important materials because they are not waste; they are really important resources that we need for remanufacturing.

Interviewed by Colin Chee, Elizabeth Price, and Luke Clark.

Edited by Claryss Kuan for length and clarity.

Images by NeverTooSmall