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If this helps to reduce the quantity of concrete used that can only be a good thing. The cement industry is responsible for 8% of all green house gas emissions and an enormous quality of particulates in the atmosphere, we really need to use less concrete!

I wander if there are other food waste products that can also be used? It would be awesome if they found somethings that was a waste product from food mass-production, something what is available in bulk with simple logistics.



It's probably not replacing the cement though -- it's almost certainly an additive in the concrete mixture, like flyash. And even if it does make the mixture stronger, there are lots of variables for that, like aggregate strength, water/cement ratio, curing times, temperatures, additives and admixtures.

Glossary for the people here who haven't taken classes from people really particular about it:

  * Cement is the 'glue' part 
  * Concrete is Cement + small aggregate (sand) + large aggregate (gravel)
  * Cement doesn't dry, it cures, and the water becomes bound in gels between the cementitious minerals. If it does dry out (due to fire, or prior to curing), it loses its strength. 
  * The trucks aren't cement mixers, they're concrete mixers.


Cool OT sidenote about this. I live in an adobe house, and I wondered for a long time what the difference is between concrete blocks and adobe bricks, in terms of their physico-chemical structure. Adobe has comparable compressive strength to concrete blocks, but unlike concrete will dissolve in water. I always found this a bit mysterious.

Turns out that the most significant difference is that in concrete (or any cementitious material), the important molecular bonds are covalent. In adobe the bonds are ionic.

Consequently, adding water to adobe easily disrupts the structure by interfering with the ionic bonds (just as it when salt dissolves in), but does essentially nothing to the covalent bonds in concrete.

Even cooler, perhaps, is that as the wet adobe dries out again, the same bonds will reform, and you get back to the original state again.


> It's probably not replacing the cement though -- it's almost certainly an additive in the concrete mixture, like flyash.

No probably about it. The article says it can replace some portion of the sand usually used in making concrete


No one told me that we’re reading the article now. That sets a terrible precedent!


> It's probably not replacing the cement though -- it's almost certainly an additive in the concrete mixture, like flyash.

Fly ash is pozzolanic, it can be used to replace 30% or more of the cement in concrete.


"Baking Soda Saves the World: New Additive in Concrete Mix Could Slash Carbon Emissions" (2023) https://scitechdaily.com/baking-soda-saves-the-world-new-add... :

"Cementing CO2 into C-S-H: A step toward concrete carbon neutrality" (2023) https://academic.oup.com/pnasnexus/article/2/3/pgad052/70895...

Looks like Baking Soda / Sodium Bicarbonate may also be useful for Hydrogen storage:

"A baking soda solution for clean hydrogen storage" (2023) PNNL scientists investigate the promising properties of a common, Earth-abundant salt https://www.sciencedaily.com/releases/2023/06/230612200329.h...

Sodium Bicarbonate is made from Sodium Carbonate.

Sodium Bicarbonate: https://en.wikipedia.org/wiki/Sodium_bicarbonate

Sodium Carbonate: https://en.wikipedia.org/wiki/Sodium_carbonate :

> Historically, it was extracted from the ashes of plants grown in sodium-rich soils. Because the ashes of these sodium-rich plants were noticeably different from ashes of wood (once used to produce potash), sodium carbonate became known as "soda ash".[12][full citation needed] It is produced in large quantities from sodium chloride and limestone by the Solvay process, as well as by carbonating sodium hydroxide


> we really need to use less concrete!

Sadly, we also need to use less coffee, since the increase in coffee consumption in Asia is about to cause an explosion in tropical forest land re-use ...


Btwn coffee and palm oil - S.E.A.'s forrests are not going to be a happy habitat forever.

I wonder, though, what adding coconut husk to concrete would do, if it were ground up like coffee...


I'm not sure storing carbon in concrete is intended for there to be less concrete, if anything they're relying on it...




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