Realising that reject glass fines from co-mingled Material Recovery Facilities (MRF) was becoming an increasing problem, Shoalhaven City Council saw an opportunity to recover the material from this ‘legacy’ glass and return it to a circular economy.
In January 2020 the council began laying the slab for an in-house designed glass processing plant at its recycling and waste facility in West Nowra. The plant was commissioned in May 2021 and its washed glass sand has attracted interest from multiple customers. More than 1800 tonnes of glass sand were produced and sold in the first nine weeks of the plant’s operation.
The plant won the Local Government New South Wales Excellence in the Environment Award for Transitioning to a Circular Economy in 2021 and the Environmental Enhancement Project including Recovery, Recycling and Reusing category at the 2022 Institute of Public Works Engineering Australia (IPWEA), Engineering Excellence Awards.
Peter Windley, Shoalhaven City Council Co-Ordinator Waste Operations, says the council and staff are proud of what they’ve achieved.
“We had legacy glass from previous poor waste practices stockpiled on site. To see that large stockpile disappear and go out the gate into asphalt for roads we all drive on, is really pleasing,” he says.
Peter says that before Shoalhaven’s glass recycling plant was built, very few glass recyclers effectively recycled contaminated glass fines, or legacy glass. The National Waste Report 2020 estimated that 41 per cent was disposed to landfill.
When the Council of Australian Governments (COAG) announced export bans on unprocessed glass the council began to research its own solutions to clean and recycle the glass while providing a sustainable pathway to a circular economy.
Peter says the council wanted a crushing, screening and washing plant which would produce a high-quality glass sand product, avoiding the need to send legacy glass fines to landfill. Initially the plant was to focus on council stockpiles, but the plan was always to allow for glass processing from the region.
The council wanted to process different feedstocks such as dirty glass fines, clean glass bottles and jars and other glass such as plate and drinking glass into high quality product for reuse within a selection of various end markets.
The glass recycling plant was to be commissioned in August 2020. But in December 2019 and January 2020, Shoalhaven was significantly impacted by bushfires, floods and then COVID-19. The $2.6 million plant was finally commissioned in March 2021.
Peter says the response has been overwhelming.
“What’s wonderful is that more than half of the 12,000 tonnes or so of stockpiled glass has been used in local infrastructure,” he says. “It’s currently being used in road base materials, asphalt, concrete, pipe bedding and green ceramics.
“Fulton Hogan, contracted to Transport for New South Wales to construct the Nowra Bridge Project, is using the glass sand produced at West Nowra for all its Nowra bridge roadworks as well as local roads within the region.
“We’re seeing the roll-out and expect more and more material to be used. We’ve got plenty of capacity in the facility. We can process up to 25,000 tonnes annually if we need to.”
Peter says processing a dirty glass sand stockpile is very different to processing clean bottles and clean crushed cullet, so the council’s plant had to be adapted.
However, through the challenge came an unexpected opportunity. A ‘super-fine’ product which would normally be considered waste was recovered in the process and has attracted a lot of interest. The plant was modified to allow for more recovery of the ‘super-fines’.
“Over time, there is more and more acceptance and vastly more interest in our products,” Peter says.
“We’re working with the University of Western Sydney on a project to create concrete made from 93 per cent glass. We’re also building a MICROfactorieTM which will take our glass and recycled textiles and make them into green ceramic tiles and other construction materials.
“Even the waste stream from the glass plant is being further refined and processed so it’s not ending up in landfill.”
Peter describes the glass wash plant as the focal point of a bigger vision to divert more than 90 per cent of Shoalhaven’s waste from landfill.
A Material Recovery Facility is being built and the council has approval to build a tyre recycling plant to produce rubber crumb. The council is also using technology to reprocess leachate into clean water which will be recycled back to the glass washing plant, creating a closed loop for water usage.
Peter says one of the big projects involves landfill gas generation. Output from the existing gas generation will be increased, and with a solar supplement, will produce about 6Mw of power on site, half of which will be exported into the network.
“It’s part of our social responsibility,” he says. “To make sure our community is benefitting from what we do, economically, environmentally and sustainably.”