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 primarily from the degrading soluble protein and lactose from residual dairy products in the plastic. The resulting odorous water was causing occupational health and safety issues for the workers and was also affecting the quality of the finished product – a pelletised plastic form of Polyethylene (PE) and Polyethylene Terephthalate (PET). The PE and PET pellets are used for products demanding high quality specifications, namely the manufacture of food meat trays and as a component in composite plastic decking material.
To resolve the odour and contamination problems, ARP was forced to regularly dispose of wastewater and refill with fresh water, as well as limit the production hours, 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, which is where Aerofloat stepped in.