More than 60% of Australian timber ends up in landfills, with the remainder burnt as fuel. However, that could all change thanks to a new breakthrough project known as the Australian Timber Circularity Project – a major boost for treated timbers and engineered wood products – both crucial in helping Australia’s transition to a net-zero economy.
Wood Central can reveal that Australia’s brightest timber researchers are now looking to reuse and recycle end-of-life timbers treated with chemicals and adhesives, which are key to extending the life of timbers ten times longer than untreated timber.
Led by the National Centre for Timber Durability and Design Life, Professor Tripti Singh, the centre’s director-in-charge, is now leading a team of researchers, including Dr Penelope Mitchell, the full-time Project Leader, Dr Martin Strandgard, Dr Melanie Harris, Dr Mohammad Reza Ghaffariyan, Dr Nami Kartal, and Associate Professor Sanjeev Kumar Srivastava, in demonstrating the full circularity of timbers.
With support from key partners*, the three-year project has already seen researchers conduct site visits and surveys and geospatially map resource volumes by location and type.
Already, regulatory challenges have been assessed, with a draft report aiding the development of information sheets designed to help industry advocacy with regulators. Logistics, critical for bringing treated timber into a circular economy, have also been analysed – with an initial case study already comparing different scenarios for collecting, loading, transporting, and chipping resources for use in new applications.
For Dr Mitchell, “recycled wood fibre is required for existing products such as particleboard and emerging products including low-carbon concrete blocks and wood-plastic composites…however, using glues and chemical treatments in wood products such as copper chromium arsenic (CCA) complicates recycling efforts.”
The project tackles the role of CCA-treated timber in the circular economy.
According to a statement provided to Wood Central by the research team, CCA-treated timber, which now makes up 30% of all treated timber, is chemically fixed onto wood fibres and can be very difficult to leach. That said, “rot-resistant preserved wood still makes an excellent carbon sink in well-managed landfills.”
“While research into extraction methods using chemical and biological means has shown promise, scaling these methods to meet regulatory standards and managing resultant toxic waste remain significant hurdles.”
Although high extraction rates are possible in laboratory scenarios, Wood Central understands that scaling up can be costly and unviable under current economic models. “There is also the issue with the resultant hazardous extractants produced by any remediation methods.”
“Clean timber will be required for many applications, particularly if the timber is used in concrete or other porous applications where leaching may occur,” the researchers said.
While the project team investigate viable remediation options, alternative avenues for CCA-treated timber are required if the 2030 Government target for a circular economy is to be met.
“With the Australian Government’s target of achieving a circular economy by 2030, it’s essential that we find sustainable pathways for all timber,” Dr Mitchell said. “This project addresses environmental concerns and explores the economic viability, logistics and regulatory challenges for recycling timber into higher-value products.”
The project’s comprehensive approach includes:
- Quantifying available end-of-life timber resources and their condition
- Mapping geospatial data to visualise resource distribution
- Addressing state-by-state regulatory challenges
- Analysing logistics and infrastructure needs for timber recycling
- Developing a hierarchy matrix for evaluating recycling solutions
- Undertaking pilot projects and documenting case studies.
“By converting challenges into opportunities, the Timber Circularity project aims to demonstrate how treated timber can play a pivotal role in Australia’s circular bioeconomy,” Professor Singh said.
- Wood Central understands that the project has support from stakeholders, including the Australian Forest Products Association (AFPA), Wine Australia (WA), Engineered Wood Products Association of Australasia (EWPAA), Frame & Truss Manufacturers Association of Australia (FTMA), Koppers, Hexion and Azelis, with the support of Forest and Wood Products Australia (FWPA).
