As we consider what we will do with our recyclables that China no longer wants, it is worth remembering that one of the key reasons for the current situation is the failure of developed nations to properly manage contamination in recovered materials.

Max AI at Athens Services’ MRF in California.

Regardless of where our recyclables go in the future, we need to deal with the contamination issue. This article explores the aspects of contamination management, including recycling behaviours in the home, collection systems and technology solutions.

At this stage, it is not clear if or when China may take our recyclables again. Recyclers are looking at options to achieve the very tight contamination limits imposed under National Sword (0.5% on plastics and fibre) but achieving the new limits is no guarantee that the material will be accepted. In addition to contamination limits, import permits are also being restricted and it is not clear if or when those restrictions will be relaxed. China wants to shake up its own recycling industry and recover more through its domestic market but it remains to be seen whether Chinese recyclers can extract and supply enough recovered material domestically to feed its massive appetite for manufacturing feedstock.

Australian recyclers will also be trying to secure outlets in alternative markets throughout South East Asia but while this may provide a short-term fix, it won't be long before those countries also realise that they need to tightly regulate the contamination issue. The other problem with this approach is that the rest of the western world will be trying to do the same thing and there are already reports that those markets have been flooded.

Industry and government have rightly noted that this is a real opportunity for Australia to develop our own reprocessing industry and move towards that ultimate, but thus far elusive, concept of a circular economy. That would be great but it will take some time to develop the reprocessing and manufacturing capacity and associated supply chains and markets.

Regardless of which outlet is ultimately pursued, we need to address the contamination issue and dramatically improve the quality of the material we are producing. It will require action along the recycling supply chain and effort by all stakeholders. It will also require investment in new processes and infrastructure, which in the current situation will likely need government support. On the positive side, any investment in quality improvement made now will not be wasted, even if we are not yet sure of the long-term destination for our materials.   


At the start of the supply chain, we need to look at how we all recycle in the home and how we can minimise the input of unwanted materials into the system. Education is key and it needs to be a coordinated effort between councils, collectors, processors and with support from state governments. Perhaps this needs a change in the way some councils do recycling education and the allocation of education responsibilities in contracts.

In our preceding article of this series, we looked at the concept of better risk sharing in processing contracts including some of the models used elsewhere in the world. In the current climate, that will invariably mean the councils and householders pay more. This in itself will actually provide an incentive for councils to be more proactive in managing contamination through education and monitoring.

The other aspect of the education discussion is data. Councils and contractors need to know what the contamination is, where it is coming from, and what demographic or other factors are driving poor recycling habits. As an industry, we are collecting increasing volumes of data from many sources - customer surveys, waste audits, inspections, collection truck technologies (cameras) and feedback from MRFs. When drawn together and used cleverly, that data can help to prioritise education campaigns and tailor messages to the real problem areas to get the easy wins.


Recycling behaviours are also a function of the collection system that is in place. Perhaps it is time to fundamentally review the way we collect recyclables from households and look at alternative kerbside systems such as two stream recycling (separate bins for paper/cardboard and containers) or kerbside sort. Streaming within the household is more common in Europe and there is regular debate in the UK as to which system is more effective, but such debate has largely disappeared in Australia.

Commingled, single-stream recycling is the easiest option for householders but results in higher levels of contamination in the sorted materials (particularly paper and cardboard). With the fundamentals of recycling markets now turned upside down, the logistics-focused economics that supported full commingled approaches over the past two decades have changed and perhaps we need to review whether this is still the best system.

For many councils, this would be a step back in time and it would need residents to take on greater responsibility for sorting in the home. It is not an impossible ask given the success we have seen with the implementation of FOGO systems across the country, so we should not underestimate householders' willingness to do their bit.


There may be changes that some MRFs can make quickly to improve product quality, such as optimising manual picking roles or slowing down processing lines, to better sort materials or remove more contamination.

Technology solutions will take time to put in place. Optical and sensor sorting technology has advanced dramatically over the last 5-10 years and continues to improve. Near infra-red (NIR) technologies are now common place in modern MRFs while newer alternatives such as laser detection offer the promise of broader application (including black items) and better purity levels. The technology already exists to separate mixed plastics by type and colour, or grade fibre into higher value streams. Washing, refining and granulating technologies are also established to provide secondary reprocessing of separated plastics for example, producing clean flakes or pellets that are manufacturing-ready.

It is a question of cost versus product value and, to an extent, scale, which makes it difficult for smaller, regional facilities to achieve the same performance as large metropolitan MRFs.

Robotic sorting is the next frontier, incorporating artificial intelligence to identify materials and improve by ‘learning' over time, together with robotic picking arms. Robotic systems employing AI can be used to target multiple specific materials from a mixed stream or to improve the purity of a stream that has already been through the optical sorters. One such technology - Max AI Autonomous Quality Control by BHS - launched in 2017 and has been installed in a handful of US plants and more recently in the UK. There is limited information on the costs and performance of these systems as yet, but there is little doubt that robotic technologies will improve and become more cost effective, possibly replacing manual pickers one day in the near future.

Unfortunately, none of the solutions offer a quick fix and almost all require some level of investment that will increase costs for the end customers - residents and businesses. But that shouldn't stop all stakeholders from getting involved in the conversation and taking some firm actions to get things moving.

Dominic Schliebs leads the Arcadis waste advisory team nationally and has worked in waste for 18 years ( while Meredith Jay is a senior waste consultant in the Melbourne office (