Plastic bags see new life as concrete

Over 800,000 soft plastic bags have been converted into a recycled aggregate replacement called Polyrok for use by a Queensland council, with the bags coming from households across the state and schools across the country.

Several tonnes of the plastic bags were provided as part of REDcycle and Goodman Fielder’s Wonder Recycling Rewards for Schools program, which involves school children trading Wonder bread bags for sports equipment.

The bags were processed into Polyrok, which is a replacement for mineral aggregate that offers thermal and weight benefits in addition to being environmentally friendly. Queensland’s first use of the plastic-filled concrete was poured by Mackay Regional Council recently.

“For the first time in our history, we have created a scalable and financially viable solution to dealing with the most problematic post-consumer soft plastic packaging in the world. That should be an exciting prospect for everyone,” said Polyrok Strategy Director Mark Jacobsen.

Made by Replas, the Polyrok is integrated into poured concrete like any other aggregate. Polyrok is able to be reclaimed and reused later, in support of a circular economy.

“Polyrok is a great end use for soft plastics that would otherwise go to landfill or end up in our oceans. These three and a half tonnes of Polyrok represent 830,000 plastic bags,” Mackay Mayor Greg Williamson said.

“Every bag that our community can collect in programs like this one, and at the REDcycle collection points, means fewer soft plastics go to our Materials Recovery Facility, where they need to be separated out, creating processing delays and increasing our landfill costs.”