The road to plastic recycling
The world has a plastic problem. Fact. However, a novel initiative is, quite literally, on the road to overcoming the problem
According to National Geographic, in the six decades since mass production of plastics began, more than 8,3-billion metric tonnes of the stuff has been created. Of that, 6,3-billion tonnes has become plastic waste, and, of that, only nine percent has been recycled.
In a 2011 article, the New York Times claimed that about 300-million tonnes of plastic is produced globally each year.
These are frightening numbers and so, too, is the fact that the vast majority of this plastic either lands up in landfills, or is left to litter the earth and its oceans. Only a small percentage is recycled or incinerated (which, itself, poses other environmental conundrums).
What about roads, then? Well, it is estimated that the world is covered by 40-million kilometres of roads (incidentally, South Africa is ranked tenth in the world, with a road network more than 940 000-km long).
The average road construction includes a mix of about ten-percent bitumen (also known as asphalt) which, while naturally occurring, is usually refined from petroleum. Road construction is the primary use for bitumen.
So, what if two problems – increasing the rate of plastics recycling and reducing the amount of bitumen refined from crude oil – could be solved at once? The concept of introducing plastic particles to the bitumen mix is becoming more widespread as more and more countries around the world investigate the possibilities of plastic roads. India and the United Kingdom (UK) are among the leaders.
In the UK, one of the pioneers is a company called MacRebur. The company produces three different recycled-plastic compounds. These recycled-plastic pellets, or flakes, are added to the bitumen and aggregate mix at between three and ten kilograms for every tonne of road mixture.
The result, according to MacRebur, is a huge increase in tensile strength of the road. This increases its resistance to deformation, rutting and cracking, which means that road maintenance is reduced, while its lifespan is increased. MacRebur claims that the roads are 60-percent stronger than those made with a traditional mix and ten-times longer-lasting.
Naturally, there are environmental advantages, too. Plastic waste is diverted from landfill, there is a reduction in fossil-fuel usage and a reduction in carbon footprint.
Good as this sounds, Dutch company VolkerWessels is taking the concept even further. It’s PlasticRoad concept might still be in the design and modelling phase, but the company claims it will present numerous advantages.
Among these, the 100-percent recycled-plastic construction will allow for power generation, quiet road surfaces, heated roads and modular construction. Additionally, the PlasticRoad design features a hollowed-out space that can be used to run cables and pipes, and to divert rainwater.
The company is currently looking for partners to study the design’s real-world practicalities.
With companies like MacRebur and VolkerWessels leading the way, the possibility of vastly reduced plastic waste and bitumen usage in road construction can only be a good thing. Here’s hoping the concepts catch on!