Concrete is currently a high-impact material, but its future could be bright with all the clever ideas and emerging technologies. Here’s one using wood waste. What else is out there in the concrete world?
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Exciting innovation! Though I’m wondering how much energy is going into the grinding process.
I was looking into Blue Planet Aggregate that uses sequestered carbon as aggregate. From the specs they show on their website, if it’s scalable and cost effective, it could do wonders for offsetting concrete GWP. Do you know anything about them @Vaclav? I know they’re based out of the Bay Area.
You are right about BluePlanet. If their claims are true it could sequester roughly double the carbon footprint of a typical concrete mix in some situations (if used as 100% coarse aggregate replacement).
It is being used on two projects we are working on but in very small amounts since the production capacity is not there yet. They are planning to open a new plant in the Bay Area soon though - hopefully it takes off from there. Also, hopefully, it follows with an EPD or LCA of some sort so there is a third-party verification on the true carbon sequestration potential.
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Hi Martin,
We are also working with them on research project to develop carbon negative concrete mixes. I believe their product has the potential to change the narrative regarding concrete. Currently no EPD as their full-scale manufacturing plant is under construction. But if you reach out to them they have plenty of information on the process.
regards,
Chris Drew
Adrian Smith +Gordon Gill Architecture
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@Vaclav @chrisdrew @martintorres I just joined this thread and I’ve been talking to a number of the reduced carbon concrete technology providers for an article. You might also want to investigate Carbon Upcycling Technologies in Calgary, which uses CO2 to create enhanced fly ash nanoparticles for 30% greater compression in cement, and Alkemy Environmental (Somerville, MA) which is not CO2 based but can use a variety of waste streams as feedstock for aggregate.
If you combine Blue Planet aggregate with CarbonCure Technology which uses the same CO2 mineralization as Blue Planet but is added to the concrete mix to reduce the amount of binder. Another interesting article I read if a proof of concept research conducted at MIT to use an electrochemical process to produce clinker versus current practice. Both interesting concepts. I’m currently working on my thesis in reducing embodied carbon in a buildings structure system so I have begun a little research on these alternatives. I’ll have to pay attention to this thread for additional insight.
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Hm these sound like some interesting products! Do you know to what extent they’ve been used on projects and successful it was? Let me know when/where you post that article, I’d certainly like to read it.
This is really interesting - I wonder if it’s possible to couple this with the electrochemical synthesis of carbon nanotubes, somehow get the CO2 from the acid bath into the LiCO3 molten salt, value adding and sequestering the carbon at the same time… https://www.sciencedirect.com/science/article/pii/S2212982016302852
Take a look at Ultra High Materials, Inc. (www.ultrahighmaterials.com). They have developed and patented a portfolio of cements and concretes that are stronger, more durable, more heat and fire resistant, more corrosion resistant, faster setting, more cost effective and greener (already achieving 80-90% reduction in embedded carbon) than anything made using ordinary Portland cement (OPC).
The Port Authority of NY & NJ is seeking participation in a low carbon concrete committee being organized with regional general contracting associations and other stakeholders. Please reach out to dbailey@panynj.gov if you would be interested in helping the region move to lower carbon concrete for our infrastructure redevelopment programs and state of good repair maintenance work.
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Hello Vaclav-
My company is one who makes biochar, which is reducing wood waste to carbon. We are the only producer in the US that is certified by the EPA and have the purest form of carbon coming from biomass that I’m aware of. Tests on concrete with our carbon as an additive show an increase in strength of 30%, decrease in water permeability of 50% and due to our process and feedstock, it is considered carbon negative or carbon reduced, thus reducing the footprint of the user. Thanks for posting this article. Very interesting! I’m learning more about our applications each day.
Hi all,
I’m seeing large suppliers like Lafarge Holcim and Cemex advertise their low-carbon offerings such as ECOPact and Vertua. Not a lot of detail is provided on either website, but has anyone looked into these in some detail?
It seems like their 30%-ish reduction products are just smart mix designs with SCMs and blended cement, while the 70%-ish reduction products are geopolymers with alkaline activators, like Ultra High Materials - but I may be wrong.
How much of this is smart mix designs + branding vs actual new tech, and does anyone have experience with implementation of these products?
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Hi Prateek-
Following up on your question here, and on yesterday’s L&L, here is a detailed answer on the technology behind ECOPact.
I work for LafargeHolcim US as Sustainable Solutions Manager, so of course this is our point of view and I welcome any other and impartial feedback.
With ECOPact we offer low-carbon mixes and related services:
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GWP savings backed up by product specific EPDs to avoid greenwashing or inefficient recipes - minimum 30% GWP savings compared to straight OPC equivalent
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GWP savings calculator for the projects, to easily show the benefits of ECOPact to our clients and their clients - In this tool we compare GWP levels to current NRMCA regional averages (this is especially relevant in regions where slag or FA are already being used at lower replacement rates).
Depending on local availability, ECOPact mixes will involve:
- SCMs (slag, FA, silica fumes, natural pozzolan)
- Blended cements (Type IL OneCem, Type IS MaxCem, Type IP FortiCem)
Today we focus on replacing cement because this is by far the main source of CO2 emissions in our process. It is not that straightforward because of sourcing challenges and reluctance to adoption amidst projects stakeholders.
We push the cement replacement rates as far as possible depending on the local circumstances and applications. We can go as far as 70% replacement rate with equal performance in some areas, but that’s not achievable everywhere. Our technical teams work on ECOPact mixes in the following ways:
- Mix development to guarantee same performance and placement, to optimize mixes using the positive properties of SCMs and to overcome possible adverse properties of SCMs.
- Work on high-early, self-placing, high rise (pumpability), lightweight, high strength, durability etc depending on projects’ needs
And finally the last thing we do around ECOPact is to advocate widely in favour of low-carbon concrete adoption:
- Reach out to architects, engineers and owners to explain what are the possibilities and benefits and to help lift barriers to adoption - This work is already being done by engineers and architects themselves with initiatives such as SE2050 or Architecture 2030.
- Partnership with GCs & Concrete contractors: explain the impacts of using SCMs and lift objections by sharing success stories and providing strong technical support
Thanks for the feedback on our website, you’re right it is not very transparent (this is our global page). The US website is a bit more specific and I’ll try to add some more information as well.
Thanks for the detailed response @Cecile_Roman. in Europe Lafarge ECOPact Max is offering geopolymer / AACM with 100% replacement of OPC, are there plans to bring this to North America?
Also I note that you benchmark against the NRMCA mixes, when we look at these baselines they are very generous, i.e., have high OPC content compared to standard mixes in use today. Can you comment on the suitability of using this as a benchmark and when the benchmark might be updated to reflect developments in the industry (e.g., the move from GU to GUL in Canada)?
@will.nash I heard somewhere the NRMCA are updating their benchmarks in 2022. Though I might be wrong. I would hope if they are then it will be more representative of what is commonly used.
On ECOPact, the one sticking point with the EPDs is that they are all to 56 day strength. Structural engineers typically require strengths at 28 days, though in foundations and vertical members it’s easier to justify the longer curing period, suspended elements will either need the faster curing or propping in for longer (pain for contractor).
@Vaclav - has this product moved forward since your original post? Seems like they’ve upgraded their website and I’m wondering if there are examples of it in structures now.