Session 2 – Circular economy abstracts

Session 2.1 Circular Economy – an approach towards re-using plastics

Lisa McLean – Circular Australia
Why reducing & recycling plastic wont be enough on its own

[abstract pending]

Anibarn Ghose – UNSW Sydney

A vision for a Sustainable Future: Innovative transformations and solutions that deliver benefits for our people and planet

A sustainable future requires development of conceptual, scientific and technological innovations and strong collaborations between research and industry partners.

The UNSW Sustainable Materials Research and Technology (SMaRT) Centre aims to boost resource recovery capability by creating new advanced and scalable manufacturing technologies, based on SMaRT’s Microrecycling and   MICROfactorieTM concepts, to recover and reform the materials from complex waste so they can be used again as manufacturing feedstock.

The world can become more sustainable by adopting fit-for-purpose green manufacturing solutions by placing greater value on waste materials and developing circular pathways for their reuse and remanufacture. SMaRT is forging new discoveries in partnership with industry partners so that technologies developed are commercially fit for purpose.

SMaRT@UNSW has a strong focus on, and track record of, translating its scientific discoveries into real world application in collaboration with industry and government partners. The Centre is focusing on recovering valuable materials from waste to help create materials sustainability and accelerate efforts to reduce emissions and decarbonise.

Richard Evans – CSIRO
Towards recyclable thermoset plastics

This presentation will discuss the challenges of recycling thermoset polymers. Polymers, also known as plastics, can be broadly divided into two types: thermoplastics and thermosets. Thermoplastics, such as well-known examples like PET, polyethylene, and polypropylene, soften and melt when heated. This allows them to be easily processed and reprocessed, and their solvent solubility greatly aids their recycling through mechanical or chemical methods. As a result, thermoplastics represent the vast majority of polymers that can be potentially or are being recycled.

On the other hand, thermoset polymers are materials that irreversibly harden. They do not melt when heated and are largely intractable and insoluble. Examples of such materials are high-performance engineering polymers like epoxy, phenolic and melamine resins, polyimides, and many polyurethanes. Recycling thermoset polymers represents a far greater challenge. We are exploring methods to build reversibility into thermosets to allow re-processability or de-polymerization and will report on our initial approach in this strategic research.

Melissa Skidmore – CSIRO
Recycling pathways for ghost nets and other marine debris in Northern Australia

Ghost nets are fishing nets that have been discarded or lost in the ocean by fishing vessels. Ghost nets and other marine debris damage marine and coastal environments, impact plant and animal species, and injure and kill marine fauna. Ghost nets and other marine debris can be highly degraded and contaminated.

This presentation will discuss an investigation into a modular recycling pathway for ghost nets and other marine debris in the Gulf of Carpentaria and Torres Strait, through the identification of a supply chain, recycling technology and market pathway. Giving an overview of opportunities and challenges that have been reality checked against the metrics of technical considerations, community desire, expectations and readiness and applicability to a remote location.

 Russel Varley – Deakin University
 Self healing coatings for service life extension of the built environment

Preventing corrosion within the built environment is one of the biggest challenges faced by the the wider construction and infrastructure industries because of its massive impact on the integrity of pipelines, off-shore platforms, and wind turbines to name a few. Harsh environments and long-term exposure are two major contributors to corrosion of metallic components and deterioration of related non-metallic components that can prematurely reduce the life of these assets. To avoid catastrophic failure, deterioration in performance requires continuous monitoring and when necessary, an effective, although complex time consuming repair processes. Self-healing coatings represent an alternative approach to sustainability where resource efficiency is a necessity, enabling service life extension, simple repair and reduced maintenance regimes for structures. 

A novel polyurethane coating containing boronic ester linkages that automatically removes scratches and cracks while only requiring moisture from the air at room temperature will be presented and will be shown to be effective, repeatable and durable.

 Heinz Schandl – CSIRO
 When we collaborate we can go further: Insights from the Australia India Research and Industry Collaboration to Reduce Plastics Waste

We are summarising the main learnings of a three-year collaborative research initiative aimed to reduce plastics waste in India and resulting in a roadmap developed with industry, government and community participants. The project was led by CSIRO and included six premier research partners from India and Australia and engaged over 40 researchers from both countries. Based on a good understanding of plastics material flows the team investigated novel policies, business models and technologies that can address the massive challenge of plastics waste in India and identified economically attractive opportunities for circularity. The participative process that resulted in the roadmap identified seven elements of India’s circular economy of plastics and laid out strategies to get there. In addition to the scientific learnings and the search for the path ahead for circularity with Indian stakeholders there a multiple insights into the value of international collaboration addressing global environmental issues.

Session 2.2 Current practices and future prospects in plastic recycling

Anupama Kumar – CSIRO/ Lucy Jackson – Kimberly Clark
Closing the loop on nappies: an Aussie trial   

The Nappy Loop Project, led by Kimberly-Clark Australia, aims to address the issue of the estimated 1.5 billion disposable nappies ending up in Australian landfills annually. In collaboration with CSIRO, Peats Soils and Garden Supplies, Solo Resource Recovery, and G8 Education, the trial has been underway in South Australia since July 2022. Laboratory and field-scale trials demonstrated successful separation of the super-absorbent polymer (SAP) from other nappy components. The project team has effectively showcased anaerobic digestion as a viable option for converting the organic materials in used nappies into nutrient-rich compost, as well as bioenergy. Since the pilot began over 4 tonnes of soiled nappies have been collected and recycled. Future steps involve evaluating scaling opportunities, assessing the safety of separated SAP for compost, and exploring dry separation for plastic recycling. This pioneering project offers a promising solution to the environmental challenges of nappy waste disposal in Australia.

Jeroen Wassenaar – Qenos
 Circular Plastics from Advanced Recycling

Australia aims to transition a circular plastics economy and has set out its strategy in the National Plastics Plan, which includes among others a ban on waste plastic exports and a 20% recycled content by 2025 for plastic packaging. Whilst investment in mechanical recycling is increasing to meet this target and recycle plastic waste domestically, it is not be able to fully address household soft plastic waste and mixed plastics that are ending up in landfill, representing approximately 60% al bl plastics packaging placed on the market. Advanced recycling through pyrolysis can break down mixed plastics predominantly based on polyethylene and polypropylene into hydrocarbons that can be a feedstock for new plastic production. Through an upgrading process this so-called pyrolysis oil can be transformed into naphtha, which is the basic platform chemical to produce nearly all man-made plastics through steam cracking into monomers such as ethylene and propylene and subsequent polymerisation. The paper will detail the global state and scale of this technology, its environmental impact and how it can address plastics circularity in Australia.

Naushad Haque – CSIRO
Life Cycle Analysis of Plastic Waste

Life cycle assessment (LCA) is now recognized as a method for measuring the environmental impacts of products, processes, and services. It provides a scientifically sound method of comparing products and processes on common grounds and to identify so called “hot spots” for reducing environmental impacts. A simplified set of indicators can be introduced as ECWW or energy, carbon-dioxide, water, and waste footprint of products to determine its environmental sustainability performance. There are several LCA software packages such as SimaPro, GaBi, and OpenLCA, databases and international standards available. A review was published and a preliminary life cycle inventory (LCI) database has been developed for advanced recycling technologies, including pyrolysis and gasification. We have used this LCI to model the impacts of pyrolysis and gasification for plastic recycling in Australia. The holistic impacts of Australia’s plastic waste management system, if advanced recycling technologies are integrated into existing infrastructure, will also be evaluated.

Justin Frank – AFGC
National Plastic Recycling Scheme

The National Plastics Recycling Scheme (NPRS) project – developed by Australia’s food and grocery manufacturing industry – will establish the largest Australian industry-led plastics recycling scheme, by taking hard-to-recycle soft plastic packaging out of waste streams and reusing it. The NPRS will make it easier to recycle soft plastics at home: through the disposal of soft plastic packaging via purpose-made bags that go into kerb-side bins, enabling the recycling of the plastic into food grade soft plastics. This will facilitate the creation of a new Australian advanced recycling industry – a circular plastics loop and cleaner recycling streams for all materials, including paper and cardboard. The NPRS unites brand owners, manufacturers, recyclers, and consumers in one powerful, nationwide scheme, transforming our soft plastics problems into circular solutions. Justin Frank will give an overview of this circular economy, the value chain, trial insights, scheme design, extended producer responsibility, governance, eco-modulated fee structure and next steps

Louise Hardman – Plastic Collective
 Plasticology, planetary health and radical collaboration

Planetary Health is quickly becoming the future focus for humanity, with overflowing landfills, marine pollution and over consumption of plastics key issues. The fundamental problem causing pollution is us ! We create ‘waste’ by discarding materials.  To eliminate material ‘waste’ and prevent pollution we need radical collaboration and sustained action to create circular solutions for all communities. Plasticology is the study of plastics as a material, the impact of mismanaging plastics and how we can transform waste to resources through a value-based system and by working together.

Graeme Moad – CSIRO
 Adopting whole-of-life strategies for polymers and plastics

Plastics have been revolutionary in numerous sectors, and many of the positive attributes of modern life can be attributed to their use. However, plastics are often treated only as disposable commodities, which has led to the ever-increasing accumulation of plastic and plastic by-products in the environment as waste, and an unacceptable growth of microplastic and nanoplastic pollution. The catchphrase “plastics are everywhere”, perhaps once seen as extolling the virtues of plastics, is now seen by most as a potential or actual threat. Scientists are confronting this environmental crisis, both by developing recycling methods to deal with the legacy of plastic waste, and by highlighting the need to develop and implement effective whole-of-life strategies in the future use of plastic materials. The importance and topicality of this subject are evidenced by the dramatic increase in the use of terms such as “whole of life”, “life-cycle assessment”, “circular economy” and “sustainable polymers” in the scientific and broader literature. Fully effective solutions, however, are still to be forthcoming.

Michael Batten – CSIRO
 Creating sustainable lifecycles – time is the only thing we can’t recycle

Advanced Recycling processes offer a path to sustainable hydrocarbon lifecyles. Pyrolysing plastics back to oil is a simple process that has established a significant global footprint. Pyrolysis shoe-horns currently ‘unrecycleable’ post-use polyolefins back into established industries, thereby displacing conventional feedstocks. This is appropriate as fossil hydrocarbon feedstocks, suffer both an existential horizon due to the need to cease fossil carbon mining, as well as a number of security of supply issues. As a market-ready technology it demands targeted niche innovations to deliver better outcomes. Market development in Australia is delayed but is accelerating. The industry is at a critical juncture, heading to either a sophisticated, local circular economy or to a primary waste industry refining plastic to a raw material for export. CSIRO’s efforts are aligned to high-value ends, delivering process design experience, ensuring high-value end uses for recycled products and developing data instruments for an efficient post-use plastics market.

Session 2.3 Biodegradable polymers – Current outlook and future prospects

Daniel Murphy – Murdoch University

CSIRO-Murdoch University-Industry Bioplastics Innovation Hub
The CSIRO-Murdoch University-Industry Bioplastics Innovation Hub is focused on developing compostable plastics that leave no lasting plastic legacy on land and in water. A major component of this project is to decrease bioplastic production costs through utilising innovative bioreactor carbon feedstock sources and the simultaneous production of high-value microbial biopolymers that create new commercial opportunities. Expected benefits include cheaper bioplastic resin chemistries and diversifying bioplastic product lines to de-risk commercial uptake of a bioplastics economy.  Since compostable plastics are made from renewable resources, including food wastes, they provide significant economic, environmental and health benefits to the Australian community, now and for generations to come.

Pete Cass – CSIRO
 Are bioplastics the answer to preventing plastic pollution?

Plastic pollution has become a major environmental challenge that threatens the health and well-being of our planet. Biodegradable plastics have been hailed as a potential solution to this problem, as they promise to break down into harmless materials after use. However, the effectiveness of biodegradable plastics in reducing plastic waste is still a matter of debate. This presentation examines the potential of biodegradable plastics as a solution to plastic waste, detailing why they are necessary and addresses their limitations. We will also provide some valuable insights and highlight some of the strategic and commercial work that CSIRO are doing to improve the performance of biodegradable plastics for greater uptake, to ultimately reduce plastic waste in the environment.

Sofia Chaudry – CSIRO
 Pathways of bioplastic production from microalgae

Bioplastics are considered environmentally friendly alternatives to their fossil-based counterparts due to the renewable feedstocks used for their production. However, not all bioplastics are biodegradable, and their feedstock production competes with food crops for land, water, and nutrient sources. The use of microorganisms such as bacteria and microalgae has attracted increasing attention for bioplastics production. Microalgae are photosynthetic, do not need arable land for mass cultivation, have higher growth rates than conventional crops, and can be grown on wastewater or seawater. However, the major challenge associated with microalgae-based products is the economic feasibility of the process. Microalgae can be utilized in various ways to produce bioplastics. The most economically viable pathway to produce algal bioplastics can be identified by technoeconomic analysis. Furthermore, a decision-making tool based on technoeconomic framework can inform research and development efforts and direct the industry towards optimizing the right process and parameters for successful commercialization of algal bioplastics.

Julia Reisser – Uluu
 Replacing plastic with ocean-derived materials
Uluu is a Western Australian start-up developing ocean-derived materials capable of replacing plastic at scale, while tackling climate change and improving the health of our seas. We produce a plastic alternative known as polyhydroxyalkanoate; or PHA for short. This material is naturally produced and truly biodegradable; just like cotton, silk and paper. What makes this natural material stand out from others, is its capacity of mimicking plastic properties really well – it repels water, it’s lightweight and durable. We use farmed seaweed (rather than fossil fuels, terrestrial crops or waste) as a carbon source to produce our PHA. Doing so provides us with the unique potential to sustainably scale enough carbon to decouple our polymer economy from fossil fuels. A significant barrier for PHA adoption is cost. At Uluu, we believe that by combining seaweed, seawater and saltwater microbes to produce PHA, we will reach cost parity with plastic. For instance, our unique saltwater fermentation process reduces the need for costly chemicals and the energy-intensive, slow equipment sterilisation processes others perform. Uluu’s prospective customers include brands and manufacturers reliant on plastic to sell their products. Rather than purchasing plastic pellets produced by petrochemical companies, they can now purchase Uluu pellets instead – a move that will support a plastic-free future.

Hafna Ahmed – CSIRO
Rewriting and repurposing biology for bioplastic degradation

Plastics such as polyesters can take centuries to biodegrade in landfills or water bodies, but some organisms in nature are slowly evolving to degrade plastic waste in their environments. Bioplastics can be more susceptible to biodegradation, with the benefit of lower net carbon emissions as they are produced from renewable plant materials. Plastic degrading enzymes produced by such organisms can be repurposed for potential industrial applications, including chemical recycling in a circular economy, environmental remediation, and designing easily biodegradable plastics. However, natural enzymes are often not optimal for industrial use due to their limited activity efficiency and thermal tolerance. By data mining genomic information from microorganisms living in high temperature environments, we have identified novel, highly thermal tolerant bioplastic degrading enzymes. These enzymes can be reengineered in the laboratory to optimize properties like activity by accelerating the natural enzyme evolution process, aided by emerging Machine Learning and Artificial Intelligence technologies.

Albert Ardevol Grau – CSIRO
 Enzymatic biodegradation of plastics

Plastic waste has become one of the most prevalent subjects in the global discussion of ecology and the environment. The use of bioplastics is one emerging method to address this issue. Another is the implementation of plastic degrading enzymes. PETase from Ideonella sakaiensis 201-F6 is an esterase capable of degrading the conventional plastic polyethylene terephthalate (PET). Lip1 is an intracellular lipase from Pseudomonas chlororaphis PA23 capable of degrading several types of bioplastics, including polyhydroxyalkanoates (PHA), polycaprolactone (PCL), polylactic acid (PLA), and polyethylene succinate (PES). A combination of artificial intelligence, ancestral sequence reconstruction5, and rational protein engineering has been used to increase the thermostability and activity of these enzymes. Here we describe the crystal structure of the improved enzymes and highlight the importance of the engineered mutations for the development of a circular economy.