Plastic waste is a major global issue and as such plastics recycling is an emerging industry to combat this environmental challenge. It is estimated that only a fraction of the world’s plastic waste is captured for reuse, despite there being many uses for recycled plastic material.

In order to begin the recycling process, plastic must enter a large tank of water to essentially clean and separate the different types of plastic. In the tank, Polyethylene (PE) floats and Polyethylene Terephthalate (PET) sinks. This process requires large volumes of water. As this water becomes contaminated, often with dairy components from ice-cream, yoghurt and milk containers, it must be regularly replaced. This can be a costly exercise, making it desirable to treat and recycle the process wastewater.

Aerofloat was contacted by Australian Recycled Plastics (ARP) to consult on its wastewater challenge at its plastics recycling plant in Narrabri, North West NSW. Narrabri has an average mean rainfall of 650mm per year and water supply is limited in the area. As such, water conservation is imperative for ARP.

When building the greenfield plastics recycling plant, ARP installed a half million litre water capture facility from the roof of the 4000m2 building, as well as a water recycling system to treat the process wastewater. This system consisted of fine screens followed by ultrafiltration.

Upon commencement of production, ARP found that a major odour problem arose at the plant as the water recycling design did not address any soluble contaminants in the water. These contaminants were being generated by the lactose from plastic products containing milk. The odours were causing occupational health and safety issues for the workers and also contaminating the final product – a pelletised plastic form of PE and PET. PET and PE pellets are used for products demanding high quality specifications, namely the manufacture of food meat trays as well as comprising a composite material for making plastic decking.

To resolve the odour and contamination problems, ARP was forced to regularly dispose of wastewater and refill with fresh water, thereby causing major interruptions to operations. The operational down time and cost of replacing the water was not a viable long-term option for the company.

ARP needed a swift solution to continue operations. This is where Aerofloat stepped in.

Aerofloat installed a MBBR and Modular DAF and within a week of operation, the odour in the plant was gone. Shortly thereafter, ARP was operating at full capacity.

The Aerofloat system has been fully operational since March 2016, making ARP a very satisfied client.

Following the success of the Narrabri project, the plastics recycling equipment supplier recommended Aerofloat for another greenfield plastic recycling company overseas. Aerofloat won this project and is currently installing the system.