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Congratulations. Curious whether the process remains carbon-neutral after counting the carbon footprint of the renewable sources themselves
> We are currently building a demo plant just outside Oxford. Where are you going to get the seawater?
Excited to see new implantations in concrete! Given the low lifespans (and thus higher environmental costs) of reinforced concrete, what are you thoughts on basalt rebar? Are sustainable reinforcement methods on your radar?
When you need a senior/lead level software engineer, contact me (info in profile.) It'd be nice to work on something that could really, actually, literally make the world a better place.
When I saw this the article title being about cement and carbon, I got excited that someone invented a way for cement to better absorb heat and solar radiation. I have to imagine global temperatures are affected by the reflection of cement quite a bit. Blacktop certainly returns heat into the air, as do roofs, but I would guess so does most cement -- why does no one talk about it? Soil aborbs, plants absorb, solid ce…
I’m confused; wouldn’t you want it to reflect the solar radiation, not absorb it? The energy has to go somewhere! Unless the energy is going into something else, like increasing some chemical potential energy, or producing electrical power, or something, if it is absorbed, it is as heat. While, if it is reflected, (some proportion of) it may leave the earth as light. I guess something which might help is if you could…
I've been recently thinking about desalinization and what people could do with the excess salt rather than re-releasing it. It makes me wonder if you couldn't bake the salt into cement thereby killing two birds with one stone, so to speak.
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Yep, exactly! The world needs CaO for cement. We have a carbon neutral process for making it. It's actually overall negative as not all carbonates we extract are usable in cement production. But as far as cement producers are concerned it's carbon neutral.
so there is no more additional burning of limestone needed? instead your process directly produces the lime, CaO? and that then binds the CO2 when curing? to my limited understanding cement production emits CO2 in two ways: by splitting limestone into lime and co2 and by burning carbon based fuels to split the limestone. your method addresses both sources of co2 from cement production? or just one of them?
The OP says they'll make money by selling synthetic limestone ("We make money from selling synthetic limestone to cement producers..."), so I think the CO2 still needs to be burned off of it before the cement is produced. However they say they already (indirectly) pulled that same CO2 out of the air, instead of the ground, so overall the process is carbon neutral.
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The ocean and the atmosphere exist in an equilibrium there is a 'balance' of relative concentration of CO2. Because CO2 can dissolve in water as CO3 and HCO3 the concentration is skewed to a higher concentration in oceans. When we take out CO2 from the oceans we lower the relative concentration, so we shift it out of balance. So the entire ocean becomes the surface area for re-absorbing CO2 from the atmosphere to re-…
But the re-absorbed CO2 will come from new limestone dissolving into calcium bicarbonate, not from atmospheric CO2. You'll be adding more CO2 to the air -increasing oceanic acidification- while increasing the ocean's ability to dissolve more CaCO3. Far from fighting global warming it sounds like this will put exactly as much CO2 into the atmosphere and double the leaching impact on shellfish and coral. I am shit at c…
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Thanks! 1. We are entering the product testing stage with our cement producing parnters in the next few months, so I'll have a better answer for you then. But from a chemical composition point of view, our product is purer than mined limestone and so should perform better. 2. Biggest bottleneck from our perspective is nailing planning permission to build our plants quickly enough to supply cement producers. Unfortuna…
Yeah cool! If you have a twitter or any other way to follow you guys I would love to - I work at a sustainability-focused startup and I know a lot of people who would be interested in this, and not all of them would be in the HN audience.