Recycled Plastics Into Roads

[MTLynn]

Could We Recycle Plastics Into Roads?
Analysis by Dr. Joseph Mercola
October 02, 2019

STORY AT-A-GLANCE

• Since China ceased importing plastic waste in 2017, cities have no market for their recyclables and pollution has grown worse
• Roads built of recycled, discarded plastic can use 1 million plastic bags for every kilometer built
• Authorities in India say their plastic roads are free from potholes, rutting, raveling or edge flaw, even after four years of use
• The Netherlands is building plastic roads which are said to be lighter, quicker to install and to last longer than traditional roads
• The University of California at San Diego installed the U.S.’ first asphalt road made with a recycled plastic binder
• Plastic pollution is an urgent problem since the world now produces 299 million tons of plastics a year, much of it ending up in oceans

Readers of this newsletter know that plastic pollution is an urgent crisis. But, as if the 299 million tons of plastics the world produces a year were not enough, the situation is actually getting worse. China had imported 40 percent of America’s plastic waste, as well as other recyclables, for the last 30 years, but abruptly banned the imports in 2017.1

This has had dire consequences and the market for recyclables has all but collapsed, leaving cities that depended on exporting to China with no buyers.

The same cities that used to earn a profit from selling their recyclable plastics and waste now must pay to have it hauled away and worse: Some are now burning their plastic waste. Incinerating plastic is, of course, a major source of air pollution, including carbon and greenhouses gasses, and no solution to plastic pollution.2 Los Angeles County has incinerated about 20,000 tons of plastic in since 2018!3

Also, those ubiquitous single-use plastic bags that so many stores refuse to discontinue are too thin to recycle along with harder plastics because they get caught in the processing machinery.4 That means they need to go to a special drop-off location for disposal — but how many people make that extra effort? The presence of single-use plastic bags all over the environment is our answer. Clearly, we need some new recycling ideas and, luckily, there are some.

Could We Recycle Plastics Into Roads?
Modifying asphalt with added plastic asphalt polymers is not a new idea. Such roads, made from virgin polymers and sometimes ground tires, have been used for decades to make high-traffic truck roads, reduce noise reduction and prevent roads from cracking from weather extremes, especially in Western countries.5

But plastic roads made with discarded, low-grade polymer are a relatively new idea that is gaining traction. It’s an idea that not only avoids creating new, virgin plastic, but reduces existing plastic waste.

In fact, every kilometer of road made with low-grade, discarded plastic uses 1 million plastic bags, saves 1 ton of asphalt and costs 8 percent less than conventional roads.6 Asphalt production is polluting, emitting 96 million tons of CO2 in the U.S. alone.7 Here is how the plastic road movement got started in India, according to the Guardian.8

"Dr R Vasudevan, a chemistry professor and dean at the Thiagarajar College of Engineering in Madurai, came up with the idea through trial and error, sprinkling shredded plastic waste over hot gravel and coating the stones in a thin film of plastic. He then added the plastic-coated stones to molten tar, or asphalt. Plastic and tar bond well together because both are petroleum products.

A modified version of the road which adds road scrap to plastic-coated gravel was tested out in March this year on a highway connecting Chennai with Villupuram. It was the first time plastic road technology was used for a national highway. It is expected to reduce construction costs by 50%."

An Early Plastic Road in India Passes the Stress Test
Jambulingam Street was one of India’s first plastic roads. Built 17 years ago, it proved to be surprisingly durable and has won favorable reviews from all segments of society. According to The Guardian:9

"The tar road in the bustling Nungambakkam area has weathered a major flood, several monsoons, recurring heat waves and a steady stream of cars, trucks and auto rickshaws without showing the usual signs of wear and tear.

Built in 2002, it has not developed the mosaic of cracks, potholes or craters that typically make their appearance after it rains. Holding the road together is an unremarkable material: a cheap, polymer glue made from shredded waste plastic."

Soon, the idea of plastic roads spread to neighboring countries like Bhutan, and the roads were given good reviews by the authorities:

"'The plastic tar roads have not developed any potholes, rutting, raveling or edge flaw, even though these roads are more than four years of age,' observed an early performance report by India’s Central Pollution Control Board. Today, there are more than 21,000 miles of plastic road in India, and roughly half are in the southern state of Tamil Nadu. Most are rural roads, but a small number have also been built in cities such as Chennai and Mumbai."

Plastic Roads Are Also Occurring in the Netherlands
Zwolle, a Netherlands city an hour west from Amsterdam, is credited with having a plastic road built from almost entirely recycled single-use plastic.10 After a test run for a year in which cars and small trucks exerted no damage on the new plastic road, a second plastic road was installed in the Netherlands city of Giethoorn. Here are some of the advantages of a plastic road, according to For Construction Pros:11

"The plastic roads are lighter, reducing the load on the ground, and hollow, making it easier to install cables and utility pipelines below the surface. Not only that, but VolkerWessels says roads could be laid in a matter of weeks rather than months and last about three times as long.

Sections can be prefabricated in a factory and transported to where they are needed, reducing on-site construction, while the shorter construction time and low maintenance will mean less congestion caused by roadworks. Lighter materials can also be transported more efficiently."

And, there are even more advantages, according to Interesting Engineering. Since flooding is a growing problem linked to climate change affecting many areas that did not flood before, it’s possible the hollow space below the modules could also keep roads from flooding by storing water.

Additionally, the modules are lighter in weight than traditional roads, so they require less heavy equipment to install and also cause less subsidence to the ground. Plastic roads even have longevity on their side; they are said to last two to three times longer than traditional roads.12

 

[MTLynn]

continued...

Roads From Recycled Plastic Come to the US
In 2018, the University of California at San Diego approved the construction of a road made with recycled plastic waste, hailing it as an achievement for the United States and a victory in the war against plastic pollution. This is how the university's student paper, the UCSD Guardian, reported the breakthrough in road construction:13

"UC San Diego is taking the initiative to head toward a greener society by installing the United States’ first asphalt road made with a recycled plastic binder as opposed to a petroleum-based bitumen binder. UCSD enlisted the U.K.-based company MacRebur Ltd. to test out its patented plastic road concept on a portion of Miramar Street and Regents Road near the Mesa Nueva graduate student housing complex.

'Recycled plastic binders are closing the loop by using plastic that had been used for something else and giving it new life, keeping the plastic out of our landfills and oceans,' Campus Sustainability Manager Sara McKinstry said. 'The recycled plastic product also has a lower embodied carbon footprint than traditional bitumen, preventing some greenhouse gases from being emitted and contributing to climate change.'"

Another Hopeful Measure to Combat Plastic Pollution
Last fall I told you about Boyan Slat, a Dutch entrepreneur whose organization, Ocean Cleanup, is addressing plastic pollution on a global scale. Slat has invented a trash-collecting barge that works like an artificial coastline. Its long "arms" catch plastic waste that is swept into its folds by water currents and then offloaded to another vessel. The collection barge does not need an external energy source — it relies entirely on the ocean currents for energy.

If it uses no power, what ushers the plastic into the barge's arms? The difference in speed at which the plastic debris, barge and water travel provides the impetus, says Slat.

If the barge and plastic floated at the same rate, capturing the plastic would not be possible because the barge is always looking for "the path of the least resistance." But regardless of any changes in wind and water speed or direction, the barge, seeking its path of least resistance, will collect the plastic because of the U-shape of its arms.

The first test of the barge's ability to remove plastic from our oceans is planned for the Great Pacific garbage patch, a 1.6 million-square-kilometer (617,763 square miles) area of ocean between Hawaii and California notorious for its vast expanse of plastic debris.

The debris has been trapped by the currents of the North Pacific Gyre, with a huge amount of it suspended in its upper water column, often in microscopic plastic particles. Slat predicts that half the Great Pacific garbage patch's plastic can be removed within five years with his innovative barge.

The Worldwide Plastics Statistics Are Staggering
Out of the box thinking like plastic roads and Slat's barge are urgently needed. The world now produces 299 million tons of plastics a year and much of it ends up in oceans. By 2050, it’s estimated that our oceans will contain more plastic than fish by weight.14

Microplastics from artificial clothes fibers, microbeads found in personal care products, broken down plastics from bottles, fishing nets and plastic bags and biosolids spread on cropland are a human-created nightmare for marine and bird life and our oceans and waterways.

Marine life, in addition to strangling on the plastic and being asphyxiated, also ingest it because the plastic can seem similar to prey species like jellyfish. The smell of plastic itself can induce foraging behaviors in fish, making plastics doubly dangerous for marine life.15

Both tap and bottle water also contain the microbeads which are a newly discovered and concerning threat to humans. A study by the University of Newcastle, Australia, finds people, on the average, are consuming so much plastic it’s like eating a credit card a week.16 Clearly, solutions like making roads of plastic to reduce plastic waste cannot come soon enough.