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Raising a glass to recycled material

Roads & Civil Works Magazine looks at the rise of recycled glass use in construction materials in road and civil projects around Victoria, and its impact on the future.

Roads & Civil Works Magazine looks at the rise of recycled glass use in construction materials in road and civil projects around Victoria, and its impact on the future.Victoria’s demand for quarry resources for infrastructure construction is set to double by 2050, according to a new report from State Minister for Resources Wade Noonan.

The landmark report, Extractive Resources in Victoria: Demand and Supply Study 2015-2050, released in July, identified that the state’s projected population growth and urban development over the coming decades will drive strong demand for nearly 90 million tonnes of stone, sand, clay and other materials annually. This is up from the 46 million tonnes needed in 2015.

The Victorian Government commissioned the study to examine the state’s future requirements for resources and to forecast where supplies are likely to come from to best meet this need.

The report compares the location of current and potential future quarry sites by local government area, with their proximity to high growth corridors and centres in the state. It identified 15 local government areas that are likely to be important in efficiently supplying growth areas across Melbourne and the state’s regional centres.

Stan Krpan, Chief Executive Officer at Sustainability Victoria, says the government’s report employs a long-term view on the situation, which is a positive step for the state. “They’re taking a 30-year view about supply and demand, and that’s where we see the real benefits,” he says. For the waste management sector, the report raises the questions about what the waste streams of the future will be, taking the projected future demand for resources into consideration. Similarly in road and civil construction, this analysis helps to promote the need to utilise recycled and recovered materials in projects, rather than using virgin quarry resources.

Mr. Krpan talks to Roads & Civil Works Magazine about the efforts being made towards recycling materials to use in road and civil construction in Victoria, and the prevalence of recovered glass content in particular.

“Victoria has one of the highest percentages of kerbside recycling in the world. Our recycling rates are among the best in the country, just behind South Australia,” says Mr. Krpan.

Out of the 250,000 tonnes of glass waste generated in Victoria annually, 195,000 tonnes, or 76 per cent, is recovered. “About half of that becomes glass cullet, which is used for recycled glass. A lot of the smaller glass and contaminated waste streams that include plastic, stoneware and ceramics, which make up the other half, become glass fine, which is used to make sand for construction,” he says.

That sand product can then be used for a variety of construction and civil projects, and has proved to be a viable substitute for virgin material in a number of applications.

Although Victoria is progressing well in the sustainable construction journey, Mr. Krpan says it has taken some significant growth in this area over the past couple of decades to reach this level of sustainability. Even now, there are still some significant hurdles to overcome, particularly in light of the projections included in Extractive Resources in Victoria report.

“In some parts of the state and country the availability of virgin resources has become more restricted and a lot more costly,” he says.

On the upside, there are many drivers towards increasing the use of recycled materials such as sand made from glass as substitutes for virgin quarry resources.

“A lot of drivers we’re seeing now are through the innovative companies that are specifying recycling in tenders and bids. There are some fantastic companies doing that,” he says.

He highlights the Infrastructure Sustainability Council of Australia’s (ISCA) Infrastructure Sustainability Rating Scheme, similar to the Green Building Council of Australia’s Green Star rating system for construction projects, has encouraged contractors and companies to include more recycled content in infrastructure projects.

The Victorian Government’s removal of 50 of the state’s most dangerous level crossings is a good example of this in action, explains Mr. Krpan. “As part of that development, companies want to achieve an ISCA rating, and that increases competition around using material such as recycled glass,” he says. “We’ve found that ISCA is making a big impact, but so is the state government, asset owners and contractors,” he adds.

“Road organisations like VicRoads are very interested in recycled content and we’ve seen some great enthusiasm from their end in getting involved in product innovation.”

Mr. Krpan says there are limitations in taking concepts, such as crushed glass in pavements, further as the new material needs to be suitable and safe to use as a material substitute in roads. However, he says that VicRoads is furthering its scope in these areas and investigating road pavement specifications that include 15 per cent crushed glass in the road base, as well as roads incorporating ground tyres. “There are also a lot of companies out there leading the way with specifications and providing input,” adds Mr. Krpan.

Sustainability Victoria is working towards increasing the use of recycled content by providing education on its benefits, and also by working closely with other organsations around the Victoria and other states and territories, particularly in New South Wales and Queensland.

“One of the things that we’re doing it looking at how other states recycle content in their roads,” he says.

Mr. Krpan agrees that the Extractive Resources in Victoria report shows there is a need to utilise recycled material further, but that for the moment the outlook is good.

“I think education around recycled content has just grown. There are better applications and some have been found to be more durable than virgin material,” says Mr. Krpan.

“If we can use recycled content, whether that’s as a substitute for sand, rock or other aggregate material from the earth, it’ll help much more in terms of costs, emissions and the environment.”

Leading the way

Alex Fraser Group is one construction material supply firm at the forefront of recycling in road and civil construction projects, and has improved glass recycling capabilities over the past 12 years. It is also a key example of industry embracing recycled material and pushing the sustainability message.

The Melbourne-based company identified the issues surrounding the significant amount of glass collected from the city’s kerbsides each year. It also acknowledged that sand sources are becoming increasingly difficult to find in metropolitan areas.

“We look for materials that the city generates and try to find a use for them. Glass is just one of these and a growing city has a lot of uses for it,” says Peter Murphy, Managing Director at Alex Fraser.

The firm has supplied Victoria with recycled content for use in road base and asphalt for 20 years. It has also supplied crushed concrete material in Queensland for the past two decades. “Brisbane City Council was the one who started using recycled content in the region in 1996, and we’ve supplied a large number of projects there since,” says Mr. Murphy. “We do more tonnes in Melbourne, and we’re supplying major projects in Queensland too.”

More than 100,000 tonnes (40 per cent) of glass generated in Melbourne each year is unable to be recycled using traditional methods because it contains ceramic, stone or porcelain. This glass has been stockpiled into ‘glass mountains’ that have grown in size for many years.

By working with government agencies, VicRoads, universities and its customers for over a decade, Alex Fraser has developed processes at its network of sites to recycle the typically stockpiled glass into sand for use in road construction – the same glass fine Mr. Krpan highlighted.

“We combined what we knew with what we had seen globally and applied it to the challenges that were specific to Melbourne,” says Mr. Murphy.

“Good environmental outcomes are not a new thing for Alex Fraser people. We are consistently developing new processes, and we have 30 years of experience at doing it to tight specifications and large volumes. It is the very core of what we do.”

In 2014, the company recycled 80,000 tonnes (80 per cent) of Melbourne’s non-traditionally recyclable glass fines.

In 2015, Alex Fraser recycled 141,000 tonnes (140 per cent) of the same material and, as a result, started to reduce stockpiled material.

Mr. Murphy says they don’t service a niche market. Its processes allow it to deliver recycled glass sand on a large scale, and that’s exactly what it does for the industry.

The growth of recycled material in infrastructure projects in Australia has seen product from firms like Alex Fraser in popular demand. From its network of facilities in Melbourne it has supplied many key projects, achieving some major milestones in the process.

In 2014, the Melbourne International Roll-On Roll-Off and Auto Terminal (MIRRAT) commenced development of a 185,000-square-metre terminal in Webb Dock West. MIRRAT assessed the project using the ISCA framework, which recognises the sustainability benefits from using recycled products. The contractor, CPB Contractors, worked closely with Alex Fraser to maximise the use of recycled products in the traditional areas of road base and asphalt, and in the use of innovative engineered fill, recycled glass sand and cement stabilised recycled sand.

The use of engineered recycled fill broke the paradigm for sourcing and placing fill on projects like this. The normal methodology is to source low quality and low value excavation material, then to place it as it becomes available.

The approach on the Webb Dock West project was to utilise a crushed recycled material that could be produced and delivered by Alex Fraser and placed at rates of up to 4000 tonnes per day. Over seven months, Alex Fraser supplied 235,786 tonnes of Class 2, 3 and 4 Crushed Concrete, 30,509 tonnes of Class 2 Crushed Rock and 8349 tonnes of Recycled Sand.

Alex Fraser’s asphalt arm commenced paving in May 2015 and nearly 30,000 tonnes of both deep and thin lift asphalt was supplied, which included a high percentage of recycled content.

By using Alex Fraser recycled materials, the project achieved logistical savings of 520 fewer truck loads on the road and a carbon saving of approximately 1567 tonnes.

“CPB Contractors used thousands of tonnes of glass on Webb Dock West, and we have many more customers using high-quality recycled content on a large scale such as that,” says Mr. Murphy.

Alex Fraser has also supplied recycled materials for use in the $156 million Dingley Bypass, and is the primary supplier of road base materials for the $570 million Bulla Road to Power Street section of Melbourne’s Tulla Widening project.

“There’s no question the use of recycled materials, including glass as sand, has become much more common in the last 10 years in Victoria,” he says. “What the industry is achieving in Melbourne in recycled material use for major infrastructure is ahead of anything we’ve seen internationally. To make this work, we’ve had customers we can work closely with, and good people in every part of our business.”

Mr. Murphy says contractors will always be focused on meeting tight specifications, demanding timelines and competitive budgets. “Experienced contractors know that using recycled material can help them meet those objectives and deliver environmental benefits.”

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