Residues – recycling and reuse
Over the last two decades the timber industry has worked towards developing and implementing drying and preservative treatment technology to allow the chemical treatment of timber and wood products in ‘final shape and form’. This best practice initiative means the volumes of waste treated wood residue from manufacture is minimised.
In recent years there has been more focus on safe disposal of preservative treated wood products.
At the sawmill, untreated wood waste (off cuts, shavings and sawdust) is utilised as an energy source or recycled back into other wood based products. When there is preservative treated waste and residues, this is disposed of in approved landfills. Australian studies have found that carbon continues to be stored in wood for a period of time after it has been transported to landfills (see the PDF below). Sawmills may have some limited approvals to burn small quantities of treated wood waste.
Generally the well-known preservative treatments have proven to be very effective in providing long term durability in the end-use applications. Therefore recycling/disposal at the end of service life has not been a significant and immediate concern. However the diversity of wood uses and potential for development of alternative specialty products with a shorter life cycle can be anticipated to bring more emphasis on the life cycle of products including recycling and disposal options at the end of the service life.
Construction of buildings using timber or wood products can also generate some sawdust and off-cuts.
- Preservative treated timber should not be burnt in confined spaces, in home heating fire or for cooking food e.g. for BBQs.
- Small quantities of off cuts may be disposed of in the household rubbish collection otherwise to a landfill.
- Treated shaving or sawdust should not be used as garden mulch or animal litter.
Forests, Wood and Australia’s Carbon Balance – Printable PDF