Researchers develop concrete solution for recycled glass

Deakin School of Engineering researchers have found ground waste glass can be used as a substitute for sand when making polymer concrete – a material commonly used in industrial flooring.

Senior engineering lecturer Dr Riyadh Al-Ameri said the addition of glass resulted in a stronger product that was less costly to produce.

“This research provides the evidence the construction industry needs to see the potential of glass as a substitute for sand when making polymer concrete and, potentially, concrete,” Dr Al-Ameri said.

“Concrete is a major construction material and sand is one of its primary components, so finding an alternative to sand makes good economic sense.”

Polymer concrete uses polymers, typically resins, to replace lime-type cements as a binder.

According to Dr Al-Ameri, this produces a high strength, water-resistant material suited to industrial flooring and infrastructure drainage, particularly in areas subject to heavy traffic such as service stations, forklift operating areas and airports.

“We have found that substituting sand with ground recycled glass makes the polymer concrete stronger and is a sustainable use of one of the major types of recyclables in the domestic waste stream,” Dr Al-Ameri said.

“Any changes that reduce the cost of production will lead to significant gains across the industry, potentially on a global scale.”

Deakin Engineering student Dikshit Modgil worked with Melbourne-based Orca Civil Products as part of his masters research into the suitability of recyclable glass in polymer concrete production.

Orca Civil Products Director Alan Travers said the research partnership had produced results that would be useful in taking the concept further to commercialisation.

“The specific type of waste glass used in this project was unsuitable for recycling back into glass and the amount that is stockpiling is becoming a community problem,” Mr Travers said.

“The concept has even more appeal to us because of predicted shortages of natural, mined sands in the medium term.”

Dr Al-Ameri said the next stage of Deakin’s research would look at substitutes for the aggregate in polymer concrete, optimising the substitution rate, assessing durability, and the commercialisation of the new product.

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Alex Fraser: recycling through the ages

As Alex Fraser celebrates its 140th anniversary, Waste Management Review details the company’s efforts to become one of Australia’s leading providers of recycled construction materials.

Not many Australian companies have 140 years of operation behind them. Such a milestone is even more extraordinary when you consider the enormous changes that have occurred over the past century – from two world wars to some of the most challenging economic recessions.

Alex Fraser is one organisation that recently hit that 140-year milestone, attributing its long history of success to investment in its people and its business. As a result, the company was able to swiftly respond to major shifts in material usage and keep pace with changing community expectations.

While the company is synonymous with building a sustainable construction sector, its humble beginnings were in the metals sector.

In 1879, Alex Fraser was a founding member of a metal broker firm, in Queen Street, Melbourne, run by the Melbourne Metal Exchange (MME).

With the price of metal fluctuating on an almost daily basis, Fraser and his fellow MME members controlled the entire output from Barrier Mines as well as other important mines throughout the country with silver, lead, zinc and tin the principle metals.

In the early 1920s, Fraser made the decision to retire and return to his country of birth, leaving the business to a clerk employed with the company – Archibald McKellar. McKellar’s 11 years with the business helped him grow the business throughout the Great Depression and eventually take over as owner.

With the passing of McKellar Snr, his son Archie took over after World War II in the 1950s. Margins were difficult at the time and with stiff competition in the tin and lead business, McKellar Jnr set looked for new opportunities, starting with the demolition and recycling of metal from returned fighter jets and tanks from the war.

Many of these initial opportunities saw Alex Fraser become a pioneer in commercial recycling, including plastics and dry nylon recycling. During the 60s and 70s, demolitions became a prominent activity for Alex Fraser and by the late 70s, its primary industry.

The early 80s marked the beginning of a new age in Alex Fraser’s recycling story as it embarked on one of its most ambitious projects yet. Led by Jamie McKellar and his brothers Robert and Peter, the family’s third generation began to transform large quantities of construction and demolition (C&D) waste, like concrete, asphalt, brick and stone, into new construction resources such as aggregates and roadbase.

With the establishment of its first concrete recycling site in Port Melbourne, Alex Fraser started to grow its employee base from an initial few to more than 260 across five recycling plants in Queensland and Victoria.

Alex Fraser Asphalt was launched in the 1990s. It quickly expanded to include two high-capacity asphalt plants on opposite ends of Melbourne’s metro area and five asphalt crews renowned for their quality workmanship and reliability.

Together, Alex Fraser’s recycling and asphalt operations work with local governments, contractors and asset owners to build greener roads throughout Melbourne and Brisbane, reducing the carbon footprint of construction by up to 65 per cent.

DEVELOPING A REPUTATION

One of its biggest milestones arose in 1992, when governments, councils and contractors began to recognise and support the use of recycled C&D. Alex Fraser worked closely with government to develop VicRoads specifications. These specifications have been periodically updated and set an outstanding example of government agencies supporting the use of recycled content.

Alex Fraser went from strength to strength, winning the Western Ring Road and Albert Park Grand Prix track projects and laying the foundations of Melbourne’s Crown Casino. As of 1987, it was responsible for almost half of Victoria’s C&D recycling effort.

By 2008, Alex Fraser became a major recycling enterprise, having produced 20 million tonnes of sustainable construction materials. Peter Murphy, who has been with Alex Fraser for more than 15 years, transitioned the company into its next phase of growth, stepping up to the role of Managing Director in 2011 after the company changed hands to John Swire & Sons.

Peter’s background in logistics drove Alex Fraser’s commitment to reliability, ensuring responsive delivery to its valued customers. He and his team consistently benchmark locally and internationally which has helped foster a culture of innovation and best practice at Alex Fraser.

Peter led the establishment of a network of world class recycling facilities, and spearheaded Alex Fraser’s innovative recycled glass projects.

Fast forward to 2019 and Alex Fraser’s notable achievements span turning glass into construction sand, converting historically landfilled concrete into recycled aggregates and roadbase, and using a wide variety of recyclables in its quality asphalt mixes, including recovered asphalt, glass and plastics.

It is now responsible for producing up to four million tonnes of sustainable construction material per annum, recovering millions of tonnes of demolition and glass waste and paving more than 1000 kilometres of green roads every year.

This year the company is in the midst of commissioning a world-first glass recycling plant and new high recycled technology asphalt plant, doubling the volume of recycled sand produced in Victoria while drastically increasing the volume of recycled materials incorporated in its asphalt mixes.

Peter credits the company’s innovation and agility to its people who are always looking for the next improvement, and to strengthen long-term relationships with customers and regulators.

“We work hard to provide reliable services, so our customers can get their projects done on time, on spec and on budget. On all our customer projects, supply timelines are integral to performance. If we can give them a high volume of consistent material, their project will be more efficient,” Peter explains.

He says that it was rewarding to see the efforts of Alex Fraser’s people recognised last year with the company winning the Waste and Recycling Award at the Victorian Transport Association Australian Freight Industry Awards.

“The prize commended our game-changing glass recycling operation that diverted hundreds of thousands of tonnes of waste from landfill and provides resources that are badly needed to fulfil Victoria’s multi-billion-dollar infrastructure pipeline,” Peter says.

“It also substantially reduces heavy vehicle movements. There’s plenty of talk about recycling lately. We’ve been doing it for a long time on a large scale and have continued to innovate and invest.”

R&D CONTINUES

Of course, none of Alex Fraser’s achievements would be possible without its continued efforts to improve the end markets for recycled materials. The company conducts ongoing research and development with partners including CSIRO, Australian Road Research Board, Melbourne’s RMIT, Melbourne University and Swinburne University. Testing over an extended period on materials and pavements demonstrates that recycled aggregate matches, if not exceeds, the performance of the equivalent virgin material.

Part of its ongoing work is liaising with individual local government areas and businesses to educate them on the environmental and commercial benefits of using recycled material.

Peter says that as natural resources deplete and quarries move further afield, transport costs increase sharply.  Recycled materials are not only a sustainable option, but often the most economical.

Alex Fraser’s desire to benchmark recycled materials led to a decision to partner with RMIT Centre of Design and conduct a life-cycle analysis of its recycling operation compared with a quarrying operation.

In May 2008, the results of the RMIT research were released indicating the carbon footprint of recycled crushed concrete is 65 per cent less than equivalent quarried material. These findings have subsequently been independently verified in accordance with international standard ISO14040.

“Demand is increasing and the constant challenge is to ensure that all of these major projects happening across the country are aware of sustainable alternatives,” Peter says.

“The consistent quality, compaction, transport and density benefits of recycled construction materials are well recognised as presenting substantial savings to construction costs, so they are well supported across the sector.”

He says that Alex Fraser’s recycled road base and aggregates comply with road building authorities’ specifications, such as VicRoads and Queensland’s Department of Transport and Main Roads, and the vast majority of local governments also support the use of recycled content.

“VicRoads has a strong track record of choosing recycled materials for some of its biggest projects, including the M1 and M80,” Peter says.

Last year, Alex Fraser developed PolyPave™ – a high-performing asphalt product containing recycled materials, including plastic, glass and RAP. Melbourne’s City of Yarra was the first of many councils to incorporate the new material in its roads through a resurfacing project in late 2018.

Peter says that Alex Fraser has been planning for the long term and sets a very high benchmark in operating standards for its sites.

“This includes ensuring our operations are ‘not seen and not heard’ through extraordinary measures to address air quality management, acoustics, traffic and visual amenity as well as constantly working to reduce the carbon footprint of our own operations and our customers’.”

Alex Fraser’s original Laverton site in the 1980s.

POSITIONED FOR GROWTH

Alex Fraser was last year acquired by construction and building material supplier Hanson Australia. Complementing Alex Fraser’s unique sustainability offering is Hanson’s technical expertise, sophisticated systems and large site network.

Peter says that Hanson’s ownership strengthens the viability of recycled materials, with great synergies between the two businesses.

“We are working together to improve efficiencies at Alex Fraser and Hanson, including recycling Hanson materials.”

As for the future of Alex Fraser? The company has continued to invest and aims to expand its capabilities with new materials and new locations.

“The new integrated facility at Laverton is a demonstration of a thriving circular economy at work. It has answered a long-standing question around how successfully waste materials can be recycled into quality resources for greener roads.”

Peter says that Alex Fraser will continue to be agile, evolving its business to align with community needs as it works towards another prosperous 140 years.

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The City of Yarra to trial kerbside glass collection

The City of Yarra in Melbourne has announced plans to trial a fourth kerbside glass bin in 1300 Abbotsford households.

According to the City of Yarra website, starting in June the city will provide residents with a purple-lidded bin for glass waste in addition to the current garbage, recycling and food and garden waste bins.

“We need to change how we recycle as individuals, as a community and as a municipality,” the website reads.

“Our current model of consumption and waste is not working for the planet, environment or our community. We’re all part of the waste system and together must all be part of the solution.”

The trial is estimated to run for 12 months and builds on a successful food and garden waste collection (FOGO) trial conducted last year.

Results from the FOGO trial saw a 40 per cent diversion of waste from landfill, with current FOGO contamination rates now averaging less than one per cent.

“Currently the glass in the kerbside recycling bin is creating contamination,” the website reads.

“Broken glass damages the quality of other materials, by removing it recycling will be better quality and more valuable to processors.”

The website highlights that a lack of available landfill space in Victoria, particularly in metropolitan Melbourne, is creating additional pressure on the waste and recycling industry.

“For years we’ve ignored the potential of locally processing our recycled materials like glass,” the website reads.

“We are being proactive and exploring new ways to collect and manage your recycling to help fix the recycling industry, create local jobs and use waste as a resource instead of sending it to landfill.”

Following the trial period the city will consider expanding the service through Yarra.

The trial will be run with support from the State Government, Sustainability Victoria, RMIT University, Australian Paper Recovery, Four Seasons Waste and Alex Fraser Group.

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Packaging MFA reveals recycling challenges and opportunities

The Australian Packaging Covenant Organisation (APCO) this week launched a Packaging Materials Flow Analysis (MFA), a new report developed in partnership with the Institute of Sustainable Futures (ISF) mapping the current state of post-consumer packaging in Australia.

Commissioned on behalf of APCO, the report highlights a compelling need to improve packaging recovery and recycling rates across all material streams.

In 2017/18 Australians generated an estimated 4.4 million tonnes of total packaging waste, with 68 per cent of this collected, and 56 per cent of the collection total recovered by recycling efforts. This ranged from 32 per cent for plastics and up to 72 per cent for paper streams – highlighting a significant opportunity to improve waste management practices to achieve higher recovery rates.

Of the 4.4 million tonnes, the report shows 44 per cent was landfilled, 33 per cent went to local secondary material utilisation, 19 per cent exported, four per cent stockpiled and more than 0.5 per cent to energy recovery.

The MFA Report is one of several APCO initiatives being conducted during the foundation phase of the targets (2019-2020) – the groundwork stage that focuses on research, engaging stakeholders and setting baselines and frameworks.

APCO CEO Brooke Donnelly said that to achieve the 2025 National Packaging Targets, we need to first understand the journey materials take along the entire supply chain and establish a baseline of data to measure change and interventions. She said that the MFA is first step in this process.

As a critical first step in achieving the 2025 national packaging targets for all material to be reusable, recyclable or compostable, the report outlines the current journey of Australia’s packaging waste from bin to landfill or reprocessing, identifies significant data and infrastructure challenges in the system and models five potential solutions for the future.

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One of the challenges is the major losses to landfill to recoverable materials occurring before waste is collected for sorting at materials recycling facilitates (MRFs) or container deposit scheme collections. The report attributes this to incorrect disposal of packaging wastes by households and businesses.

“Better management of this waste at the source, through improved source separation, is important. Critically, consumer education and awareness raising around appropriate disposal and collection channels, as well as smarter design of packaging for recycling, are also key strategies. These are already supported by the new Australasian Recycling label (ARL) and the Packaging Recyclability Evaluation Portal (PREP),” the report says.

Additionally, the report shows the opportunity to increase sorting efficiency by diverting materials, especially glass, from kerbside to the expanding container deposit scheme collections. It finds better sorting equipment will also support improvements in contaminant removal. The report shows there are about 100 MRFs in operation across Australia, with throughput capacities ranging from 5000 to 250,000 tonnes per annum. Around 45 per cent of the total packaging waste stream for 2017/17 gets directed to MRFs and their capabilities for efficiently sorting co-mingled and highly contaminated waste is indicated to be a major factor limiting packaging sorting efficiency in Australia.

“Upgrading existing MRF capabilities is difficult and expensive owing to market uncertainties (e.g., caused by Chinese waste import restrictions), making the case for improving up-stream source separation and collection stronger,” the report says.

Future modelling shows potential to achieve an overall packaging waste recovery rate of 77 per cent, assuming a range of strategies are adopted to address losses across the whole chain, from collection to processing.

With glass packaging, the estimated recovery rate is just over 50 per cent and 23 per cent of glass waste disposed to the residual stream. About 80,000 tonnes of glass is collected and sorted through container deposit collection systems.

The investigation in particular highlights the importance of improving source separation, particularly for plastics to address residuals, a priority for paper in reducing contamination (embedded glass fines) that could be achieved with separated paper or glass separation and diverting glass to CDS to improve the quality of the stream to be suitable for bottle to bottle recycling.

Institute for Sustainable Futures (UTS) Research Director and co-author of the report Dr Nick Florin said that there is great potential to step-up material recovery from the current overall recovery rate of 56 per cent and at the same time increase demand for recycled materials to drive the transition to a circular economy for packaging.

“APCO, as the central product stewardship organisation, is well placed to support this coordinated transition that involves cooperation between consumers, designers, recyclers and packaging manufactures,” Dr Florin said.

The MFA also highlighted significant data and infrastructure gaps that need to be addressed before the 2025 targets can be achieved. These findings will be used to inform additional packaging and recycling research to develop a complete picture of the current system.

Ms Donnelly said we can’t implement effective and meaningful changes to the system if we don’t first have a complete and accurate picture.

“A collaborative approach will be critical to building this. The challenge ahead of us requires a complete transformation of the current system. Over the next 12 months, APCO will be leading an ambitious agenda of projects to build on the findings of the MFA. We look forward to working closely with all stakeholders as we transition to a circular model for packaging in Australia,” she said.

Throughout 2018 APCO also facilitated a series of five, year-long industry working groups attended by more than 80 industry members from across the value chain and government to explore solutions to problematic packaging types (including glass, polymer coated paperboard (PCPB), soft plastics, biodegradable and compostable packaging, and expanded polystyrene).

In 2019, APCO will be co-ordinating 22 new projects to build on the findings of the MFA and the 2018 working groups. These will include further detailed research into packaging consumption and recycling to establish baselines for the 2025 targets, developing targeted design resources to improve packaging recyclability, and developing strategies to address problematic packaging, including plastics.

To read the full APCO Packaging Material Flow Analysis 2018, visit the APCO website.

City of Fremantle uses recycled glass in road resurfacing

The City of Fremantle has used recycled glass equivalent to around 2640 glass bottles to resurface the car park at the North Fremantle Post Office.

The City of Fremantle has used recycled glass equivalent to around 2640 glass bottles to resurface the car park at the North Fremantle Post Office.

A warm asphalt mix used 10 per cent crushed glass as a substitute for traditional crushed granite aggregate, alongside recycled road base.

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City of Fremantle Infrastructure Engineering Manager David Janssens said while recycled glass asphalt had been used on roads in the United States and Canada for many years, it’s not widely used in Australia.

“Extensive testing was undertaken by our supplier to ensure the material complied with our requirements and the glass would not come loose when cars drove over it,” Mr Janssens said.

“We also had to make sure the glass being used had no sharp edges so it was safe for people to walk on and wouldn’t damage car tyres.

“Once we get an idea of how it performs in North Fremantle we’ll consider using recycled glass in other road projects, and our suppliers are exploring the possibility of using recycled plastic and rubber in asphalt as well.”

Fremantle Mayor Brad Pettitt said the move was part of the city’s One Planet strategy, which focuses on reducing waste and increasing recycling.

“Using recycled glass in asphalt for our roads and car parks could help to create an important local market,” Cr Pettitt said.

“And because the glass asphalt is made at a much lower temperature it also means using a lot less energy and producing less greenhouse emissions.”