Recycling Waste: From aeroplane wings to permeable pavements
What if you could reduce flooding by using a product made from waste materials? That’s the question that researchers at Washington State University are attempting to answer.
Most paving slabs aren’t permeable, so rainwater simply sits on the surface and runs off them. If the drainage system can’t cope with the volume of rain, especially in a storm, then you get flooding, and this is increasingly becoming a problem in built up areas.
Pervious concrete has been developed previously, but it is not as durable as traditional concrete so more work was needed to come up with a strong solution.
Academic researchers have been working in conjunction with Boeing to incorporate a waste product into their concrete mix that strengthens the substance.
The waste product is a carbon fibre composite material that comes from the manufacture of aeroplane wings. These composites are becoming more common and are used in wind turbines and cars too, but the waste products can be up to 30% of the material used in production, so the industry needs to find ways to recycle this.
By mechanically milling the materials, i.e. not using heat and chemicals, the research team created a “reinforcing element” they could use to strengthen their concrete. They deliberately used an inexpensive milling method, as it defeats the object of using recycled materials if there are high energy costs involved.
They dispersed the composite materials throughout the pavement mix to give uniform strength.
The results in the lab have been very good and researchers are now beginning to do real-world tests.
The next steps are:
1. Developing a supply chain
2. Encourage widespread usage
To me this sounds like a positive development, as we need to do more to make the most of our planet’s resources by recycling and reusing. This product does this, as well as helping to tackle urban flooding.
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