By 2040, there could be 1.3 billion tons of plastic in the environment globally. Numerous benefits accrue from building a layer of plastic into roads. It keeps plastic from the oceans and landfills, and improves the life-expectancy of the average road, slowing deterioration and minimizing potholes, while improving the surface’s flexibility. It saves three tons of CO2 for every kilometer of road and results in savings of roughly $670 (£480) per kilometer of road. The plastic doesn’t have to be sorted or cleaned before shredding. A very simple process, it requires little high-tech machinery. First, the shredded plastic waste is scattered onto an aggregate of crushed stones and sand before being heated to about 170C–hot enough to melt the waste. The melted plastics then coat the aggregate in a thin layer. Heated bitumen is added on top, helping solidify the aggregate, and the mixture is complete.
www.bbc.com/future/article/20210302-could-plastic-roads-make-for-a-smoother-ride