Asfalto de plástico. Crédito: Divulgação/PlasticRoad

Recycled plastic paves the way for stronger asphal

British company has developed a technology that converts recovered plastic into input for a long lasting and eco-friendly asphalt. India already makes use of such material, and European cities are to follow the same road

In a future not very far, roads and urban streets in your city may be paved with a new type of asphalt, whose plastic is collected from oceans and landfills, as the main input. This is the proposition of British company MacRebur, which recently received an award by billionaire Richard Branson at the startup competition VOOM.

MacRebur’s story started when its founder, Toby McCartney, visited India, a country where excessive plastic waste is a significant concern, but also where there’s heavy investment in solutions using recycled plastic as raw material. A particular project caught his attention: turning plastic into asphalt.

Back to England and impressed by what he had seen, McCartney started working to develop a similar solution. He started with a formula that took advantage of the plastic’s best features, turning the material into the basis for a new type of asphalt. After trying 600 different recipes, he found the ideal solution. In this solution, plastic waste is "pelletized" into small granules and replaces 20% of the sticky, oil-based bitumen that seals traditional roads.

“All our plastics are heated to around 180 degrees,” said the founder of MacRebur in an interview to US news outlet CNN. “They then fully homogenize it, mixing it with the remaining bitumen in the road... So there is no micro-plastic present in any of our roads," he adds. The raw material will be acquired from organizations responsible for cleaning landfills and oceans.

"We want to solve two world problems. On one side we call it the waste plastic epidemic, and on the other side, the poor quality of roads we have to drive on today," says the engineer. McCartney claims his plastic roads are 60% stronger than traditional roads. According to CNN, lab tests estimate that this “plastic asphalt” may last up to three times longer.

“At the end of the day, plastic is a great product," says McCartney. "It lasts for long, which is a problem if it's a waste product, but not a problem if we want it to last [as in the case of asphalt],” he added.

Every ton of asphalt contains approximately 20,000 single-use plastic bottles or around 70,000 single-use plastic bags. To date, McCartney's business, MacRebur Plastic Roads Company, has provided plastic pellets for roads in the United Kingdom, as well as Canada, Australia, and New Zealand.

India’s decade-old example

In 2001, chemist and university professor Rajagopalan Vasudevan realized that a solution for plastic waste was needed in his country - at that time, there were even suggestions to ban the use of the material. “Banning plastic can severely affect the quality of life for a low-income family. But if you burn it or bury it, it’s bound to affect the environment,” he affirmed in an interview to the British newspaper The Guardian.

Mixing recycled plastic with asphalt seemed the most promising idea to Vasudevan. The idea quickly gained support at Thiagarajar College, where, in 2002, he paved a 60-ft road within the campus, using plastic-modified bitumen. The road is still intact today.

Currently, India has almost 10,000 kilometers of paved roads with Vasudevan’s solution. Every kilometer represents an economy of one ton of bitumen, replaced by one ton of recycled plastic. The greatest challenge is finding sites to buy a massive amount of recycled material, says The Guardian.

“Plastic isn’t the problem. We are. Plastic wouldn’t clog our oceans or our landfills if we didn’t throw it there in the first place. And there is so much we can do with it instead,” the venerable scientist says.

More cities buying into the idea

In 2012, Vancouver, in Canada, announced it plans to adopt asphalt made of recycled plastic. "We are using about 20 percent less fuel at the asphalt plant – so, it is an enormous saving in [generating] the greenhouse gases associated with that," explained Vancouver city engineer Peter Judd to the Canadian network CBC. In 2017, Vancouver performed the first test with the material produced by MacRebur.

In the Netherlands, the city of Rotterdam also announced its intention to replace traditional asphalt for recycled plastic-based pavement. In 2015, the city council reached an agreement on using the technology developed by the company VolkerWessels, which makes pre-build pitch blocks from plastic collected from oceans.

According to VolkerWessels, the lifespan of each block may last 50 years and could withstand greater extremes of temperature, between -40ºC and 80ºC. “Plastic offers all kinds of advantages compared to current road construction, both in laying the roads and maintaining them” states Rolf Mars, the Company’s Director, to the British newspaper The Guardian.