When asked what the greatest challenge is facing the Australian organics recycling industry, the answer is unfortunately too easy – contamination.
It is also apparent that this is not unique to organics, with all recycling streams facing the issue to some degree.
By its very nature, contamination – the action or state of making or being made impure by polluting or poisoning – is a problem, says John McKew, National Executive Officer of the Australian Organics Recycling Association.
“You don’t hear about good contamination events,” he says.
But why is it a problem?
For organics recycling, contamination can be extremely varied in its type and consequently, difficult to detect. When it comes to chemical contamination for example, perfluoroalkyl and polyfluoroalkyl substances (PFAS) – also known as ‘forever chemicals’ – or micro-plastics, are not visible.
Then you have everything else that can be visible – glass, metals, syringes, macro-plastics, packaging including non-certified compostable packaging, polystyrene, etc.
The contamination possibility list goes on and on. This makes the complete removal of contamination almost impossible in an organics recycling stream and what you can remove takes a lot of time, effort and money.
John says potentially the most important consequence of organic recycling contamination is that it can impact on the quality of the end product – the compost, mulch, or soil conditioner – especially if the contamination is high and too difficult to remove.
“The old saying is that you can’t make a silk purse from a sow’s ear,” John says. “And you cannot make quality compost, mulch, or soil conditioners from badly contaminated feedstock, such as food organics garden organics (FOGO).
“If we cannot sell the end product because of poor feedstock or contamination, we do not have an organics recycling industry.”
There are machines and technologies that can aid part of the process of decontamination, but they come at a cost. In many organic processing facilities there is a picking station where people stand either side of a moving conveyor of organic waste, removing visible contamination by hand.
That works, but it cannot guarantee complete removal as the conveyor moves constantly and the pickers only have seconds to remove an obvious contaminant. This too is costly, especially if there are six people (three aside of the conveyor), which is not uncommon.
“I visited an organics recycling facility recently when there was one person dedicated to removing syringes from organics feedstock arriving at the facility and alarmingly, he had a bucket of them,” John says.
“Not all were related to illicit drug use either, many were from the treatment of diabetes. I admit, that shocked me. I thought syringe disposal mentality by a diabetic requiring insulin injection would be very good and that it would not include the green organics bin. I was wrong, again.”
So, what is the answer to this contamination dilemma?
The short answer – there is no easy solution.
John believes several strategies will need to be employed, some of which already are, and over time technology and artificial intelligence may be able to provide better outcomes. But he says from an Australian organics recycling perspective, the issue of contamination is not the industry’s problem to deal with on its own. It’s a whole supply chain issue.
“If contamination is reaching an organics recycling facility, then it is arguably too late for effective intervention, especially if it is a chemical contamination. The end of the supply chain is not the right place to regulate contamination, yet some of our state regulators are trying to do just that,” John says.
“We have to start at the beginning of the supply chain, phasing out the use of problematic chemicals such as PFAS, ensuring there is adequate mechanisms and availability for the correct disposal of other contaminants. Container deposit schemes (CDS) are one example of an effective strategy for diversion. Education and legislation must have a role to play too.”
AORA is increasingly advocating that Australia should be aiming for a maximum of two per cent contamination in organics feedstock, by weight. Plastic is not very heavy so even two per cent can be a lot. John says the sector should be seeking to reduce that level over time.
“If we want a successful organics processing industry, and we do, then we all have to take responsibility,” John says. “That’s consumers, local councils who provide and collect our bins, the transport companies that take the waste to a recycling facility, the recycling processor and the government. All of us!”
For more information, visit: www.aora.org.au