Sources: Elhacham et al. (2020), Hackney et al. (2021), UNEP (2022)
Lots of powerful triangles to be seen here… Ancient Egyptians had them, too.
“Now, we are running out”
Uh, elaborate?
Much of the problem lies in the type of sand needed for construction, with desert sand “largely useless to us” as its grains are the wrong shape. “Eroded by wind rather than water, they are too smooth and rounded to lock together to form stable concrete,” explained the BBC. “The sand we need is the more angular stuff found in the beds, banks, and floodplains of rivers, as well as in lakes and on the seashore.”
Fascinating. I wonder if the rounded desert grains could be processed in such a way as to make them angular, say by crushing?
I have no idea what I’m talking about but could the angular sand extracted from rivers be replaced by round sand from the desert? Over time, that might be shaped into the way we like it, right?
Problem is sand is being dredged from poor areas that rely on shallow water environments for survival, aka fishing. Companies come in, take all the sand, destroy the environment in the process by deepening these shallow water environments and driving away all the fish - leaving the local population destitute as the local government recieves the payout without them seeing a cent.
Interesting, but they neglect to mention why desert sand is unusable.
This recent video by Business Insider talks about it and shows how it’s mined. It comes down to the shape.
In case you don’t know, desert sand is very smooth, which means that it doesn’t bind at all in e.g. concrete. For cement, concrete etc., you need sharp sand, which has more ‘sharp’ bits for things to bind to.
Only some sands are suitable for the construction industry, for example for making concrete. Grains of desert sand are rounded by being blown in the wind, and for this reason do not produce solid concrete, unlike the rough sand from the sea.
https://en.wikipedia.org/wiki/Sand#Resources_and_environmental_concerns
So am I correct in guessing it at least (if quartz sand) can be used for microchips and the likes? I hope the rough sands aren’t extrated just to be used in something, were other, less scarce sands could be used - but I could at least imagine stuff like economy of scale, existing infrastructure and special interest of the established industries could actually cause that.
But the amount needed for chips is several order of magnitude lower than what needed for concrete. If you see the square, usage diagram on the lower left, chips aren’t even visible, so small is needed.
You can also use it for glass, which is on the diagram, there is this old video of a guy 3D printing things with only solar power in the Sahara:
- original video: https://www.youtube.com/watch?v=ptUj8JRAYu8
- background: https://www.youtube.com/watch?v=kpunlLk4fgE
We don’t really have an economical alternative to concrete (yet) in a lot of usecases, e.g. building foundations, substructure everywhere on the earth is made from concrete. On superstructure there are other options as structural material, e.g. wood, steel, but those don’t like to be put in soil.