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Launch HN: Heimdal (YC S21) – Carbon neutral cement

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Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#101

Post by twic »

marcuslima wrote: post #72
LeifCarrotson wrote: post #66

Earlier quoted context omitted.

I understand that calcium salts and bicarbonate ions are common in the ocean, and are increasingly common as the oceans become more acidic, but have no idea how common that is. How much seawater do you need to get one kg of CaCO3 precipitate?

We're actually working on figuring this out. Our current calculations assume we need to process a huge amount of seawater (11,000 tonnes per tonne of CO2), if the CO2 is the limiting factor (2000 umol). However our R&D suggests undersaturated seawater re-absorbs CO2 from the air surprisingly quickly. Might be able to get this 10x lower

Is it surprising? Carbon dioxide equilibrates between salty water and air fast enough to keep every single terrestrial animal on the planet alive, after all.

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#103

Post by ne0flex »

Very interesting. I'd definitely like to hear more about your business plan and your plans moving forward. I work for a Japanese bank and help connect startups with the bank's Japanese corporate clients in the US, and Asia (and soon Europe). Many of the bank's clients are looking for solutions like this. Happy to connect if you're interested.

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#104

Post by Jolter »

f6v wrote: post #50
go_elmo wrote: post #28

Earlier quoted context omitted.

How "flexible" is the production? I mean during peak-sunny hours the price of electricity is well below that mark in some regions of europe? And would it e.g. make sense to scale up in a very sunny region & produce your own power? Last question: Do you need electrical power or heat? If latter, would a more efficient thermo-solar power plant make sense? Best of Luck! :)

> And would it e.g. make sense to scale up in a very sunny region & produce your own power? It’s an interesting point. The most sunny region might be not the target market. Then you need to factor in the CO2 emissions arising from the transport to consumers.

This kind of scale would require establishing factories all over the world. Every feasible region in every developed country.

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#105

Post by froh »

marcuslima wrote: post #53
brilee wrote: post #49

I'm not sure I understand where the carbon savings comes from. The cement industry specifically needs lime, CaO. Lime is most easily obtained by burning CO2 off of limestone, CaCO3. As you point out, this is effectively "burning off" captured carbon dioxide and is bad. Where does the carbon savings come from when the ultimate destination is to just burn CO2 off and make the actual desired product, CaO? Is this proces…

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?

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#106

Post by Aachen »

marcuslima wrote: post #51
Aachen wrote: post #45

Did I correctly understand the idea if I summarise the product as similar to Climeworks, capturing atmospheric CO2 (indirectly through the ocean, same thing in the end), but with the difference that you can sell the resulting product as cement ingredients (plus some byproducts) rather than it being just stored away like Climeworks does? If this is (roughly) correct, what price point per ton of removed CO2 are you at…

Yeah, that's the core of it. Climeworks absorbs CO2 on their amine solid sorbent surface before releasing it by heating up the sorbent to prepare it for a new round of CO2. That CO2 then needs to be stored somewhere. I'm not familiar with the inner workings of Climeworks, but if I were there that would be what concerned me the most. I know they're testing a mineralization solutipn with Carbfix in Iceland that could b…

$50/t sounds amazing! That would be a price point where I could offset 100% of unavoidable CO2e emissions quite easily. Too bad it won't initially be available for consumers, but I'm very much looking forward to seeing where this goes :)

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#107

Post by hwillis »

marcuslima wrote: post #67
hwillis wrote: post #56

Earlier quoted context omitted.

why does removing carbonates cause the ocean to absorb more CO2, though? Calcium and magnesium oxide aren't just floating around the ocean waiting to absorb more CO2. Removing salts does not lower oceanic acidity.

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 chemistry and would really like cement to not release CO2, but I don't understand this.

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#108

Post by marcuslima »

danieka wrote: post #98

From my limited understanding this seems really impressive! I immediately associated this to possible disruption in the cement supply chain that's about to hit Sweden. Cementa, which produces about 75% of Sweden's cement, will no longer be allow to mine limestone on Gotland. Their permit was due to be renewed but due to the low quality of their environmental impact study the court was unable to determine if the minin…

Yes! This is awesome, I saw this a couple weeks back. We're trying to get in touch with Cementa, but it seems Scandinavian holidays are getting in the way so far. Definitely an ideal place for us to start. That plant does 70% or so of Sweden's cement consumption

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#109

Post by marcuslima »

justshowpost wrote: post #89

If this is as good as promised, you should apply for Elon Musk's XPRIZE [1]. Take the $50 million to scale this up faster. Plus, if you win you probably get to talk to Elon. I doubt there is anyone that has better tipps on how to scale and iterate a business than him. [1]: https://www.xprize.org/prizes/elonmusk

Definitely one for us to get involved with. Unofrtunately it's a 5 year timeline, but that's still not a bad ROI

Re: Launch HN: Heimdal (YC S21) – Carbon neutral cement

#110

Post by marcuslima »

K5EiS wrote: post #84
matsemann wrote: post #16

Curious about the name, my immediate thought (and interest making me click in) was that it sounds Norwegian. Any connection? I really like the idea. One thing I'm curious about is what's in it for the contractors (edit: cement producers) buying from you instead of others? I get the environmental impact, but my guess is they only care if touches their bottom line. Will it be cheaper, either in raw price or because of…

It is norwegian! My SO lived in Heimdal, Trondheim.

I love Trondheim! Gorgeous city
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