One way to get rid of waste plastic is to make roads out of it.
Most asphalt road pavement is about 95 percent sand and gravel; only about 5 percent is bitumen, the sticky black stuff that holds everything together.
MacRebur, a Scottish company, has found a way to grind up old plastic bottles and shopping bags and melt it to replace much of the bitumen used now. It’s laid roadways in Australia, New Zealand, the UK, and on the campus of the University of California at San Diego.
Independent tests have found that plastic roads are about 60 percent stronger than asphalt pavement and are more flexible, meaning they’re less likely to crack as the underlying ground shifts, so they will last longer.
Dow Chemical is developing a similar process.
Technisoil Industrial, a California company, goes an extra mile: its unique “Recycling Train” machinery peels up existing pavement, grinds it, stirs in granulated plastic, melts the mixture, and lays it back down in one continuous process.
It claims that its plastic binder, which can consume as many as 1.2 million used plastic bottles for every mile of two-lane roadway, is six times stronger than bitumen and can extend pavement life as much as fivefold.
Further off the beaten track is KWS, a Dutch asphalt producer who is testing roads made entirely of interlocking modular panels fashioned from recycled plastic.
The panels have solid tops and bottoms separated by stubby structural columns that leave open spaces between the panels. The spaces hold water from snowmelt or storm runoff; they also can serve as passages for electrical and optical cables or piping.
KWS says its “PlasticRoad” will last three times longer than conventional pavement, can be laid 70 percent faster, and can be recycled to make new PlasticRoads when the panels start to break down.
TRENDPOST: Innovators will continue to find ways to turn our landscape of waste plastic into raw materials for new processes to feed the circular economy. Collecting and recycling plastic will grow from an afterthought or greenies’ hobby to be recognized as a legitimate and profitable industry.