It is also worth pointing out that the GP's comment was showing the chemistry for a lime-based concrete. OPC (Ordinary Portland Cement) based concrete is substantially different in terms of the chemistry and the amount of energy involved in the manufacturing process (due to the increased amount of energy involved in producing the clinker).
It is too bad more isn't done with lime mortars and plasters. Hydrated lime (CaO + H20 => Ca(OH)2) reacts with CO2 to form CaCO3 + H20. And it is fun to work with ...
That can, at best, absorb the CO2 that was emitted when the CaO was made, if the CaO was made from limestone. To get CO2-free CaO would involve decomposing calcium silicate, perhaps by acid dissolution followed by the energetically expensive step of separating calcium chloride into lime and hydrochloric acid.
Yes... but another advantage here of lime over Portland cement is that the cooking of the limestone doesn’t require as much heat as the cooking of Portland cement. It won’t be carbon neutral, but it is a big improvement.
That is me. I haven't seen much development effort since I switched to Rust. But ... I would still mentor someone who wanted to work on it or do something with it.
I was never at that level but still was very interested by your selfless work on OpenDylan. I was going through a Lisp adoration phase (not that it ended, really; one of many cycles I have) and found Dylan as "Apples prescient Lisp without parens from the future" elevator pitch and was surprised its tooling was better on Windows than Mac, basically because of you driving a very smally community of volunteers.
* https://www.youtube.com/watch?v=BDSee1-4bUI (How to make...)
* https://www.youtube.com/watch?v=pfBGGuezus8 (Shiny Graphite Ball made from Clay and Graphite)
* https://www.youtube.com/watch?v=jG7wHTmKtjQ (Textures in Dorodango)