Displaying items by tag: carbon sink

One unusual thing about coverage of cement in the media is the way that discussions often centre precisely on its absence – that is, on alternatives to cement. These alternatives boast unique chemistries and performance characteristics, but are all produced without Portland cement clinker. They are generally called ‘alternative cements,’ perhaps because ‘cement-free cement’ does not have such a commercially viable ring to it. This contradictory tendency reached a new high in the past week, with developments in alternative cement across Asia, Europe, the Middle East and North America. Together, they hint at a more diverse future for the ‘cement’ industry than the one we know today.

Asia

In Indonesia, Suvo Strategic Minerals has concluded tests with Makassar State University of a novel nickel-slag-based cement. Huadi Nickel-Alloy Indonesia supplied raw materials, and tests showed a seven-day compressive strength of 37.5MPa. Suvo Strategic Minerals says that a partnership with Huadi Nickel-Alloy Indonesia for commercial production is a likely next step.

Europe

Cement producer Mannok and minerals company Boliden partnered with the South Eastern Applied Materials (SEAM) research centre in Ireland to launch a project to develop supplementary cementitious materials (SCMs) from shale on 7 October 2024. The project will additionally investigate CO₂-curing of cement paste backfill for use in mines. Irish state-owned global commerce agency Enterprise Ireland has contributed €700,000 in funding.

UK-based SCM developer Karbonite expects to launch trial production of its olivine-based SCM with a concrete company in 2025. The start-up launched Karbonite Group Holding BV, with offices in the Netherlands, to facilitate this new phase. Karbonite’s SCM is activated at 750 – 850°C and sequesters CO₂ in the activation process, resulting in over 56% lower CO₂ emissions than ordinary Portland cement (OPC). Managing director Rajeev Sood told Global Cement that talks are already underway for subsequent expansions into the UAE and India.

Back in the UK, contractor John Sisk & Son has received €597,000 from national innovation agency Innovate UK. John Sisk & Son is testing fellow Ireland-based company Ecocem’s <25% clinker cement technology in concrete for use in its on-going construction of the Wembley Park mixed development in London.

At the same time, Innovate UK granted a further €3.23m to other companies for concrete decarbonisation. Recipients included a calcined clay being developed by Cemcor, an SCM being developed from electric arc furnace byproducts by Cocoon, a geopolymer cement technology being developed by EFC Green Concrete Technology UK and an initiative to develop alternative cement from recycled concrete fines at the Materials Processing Institute in Middlesbrough. Also included was the Skanska Costain Strabag joint venture, which is working on the London stretch of the upcoming HS2 railway. The joint venture, along with partners including cement producer Tarmac and construction chemicals company Sika UK, will test low-kaolinite London clay as a raw material with which to produce calcined clay as a cement substitute in concrete structures in HS2’s rail tunnels.

Middle East

Talks are underway between UK-based calcined clay producer Next Generation SCM and City Cement subsidiary Nizak Mining Company over the possible launch of a joint venture in Riyadh, Saudi Arabia. The joint venture would build a 350,000t/yr reduced-CO₂ concrete plant, which would use alternative cement based on Next Generation SCM’s calcined clay.

North America

Texas-based SCM developer Solidia Technologies recently patented its carbonatable calcium silicate-based alternative cement, which sequesters CO₂ as it cures.

Meanwhile, C-Crete Technologies made its first commercial pour of its granite-based cement-free concrete in New York, US. C-Crete Technologies says that the product offers cost and performance parity with conventional cement, with net zero CO₂ emissions. Its raw material is globally more abundant than the limestone used as a raw material for clinker. Other abundantly available feedstocks successfully deployed within C-Crete Technologies’ repertoire include basalt and zeolite.

Across New York State, in Binghamton, KLAW Industries has succeeded in replacing 20% of concrete’s cement content with its powdered glass-based SCM, Pantheon. KLAW Industries has delivered samples to local municipalities and the New York State Department of Transportation. Its success expands the discussion of possible circular cement ingredients from the industrial sphere into post-consumer resources.

In Calgary, Canada, a novel SCM has drawn attention from one of the major cement incumbents: Germany-based Heidelberg Materials. It invested in local construction and demolition materials (CDM)-based SCM developer EnviCore on 9 October 2024. The companies plan to build a pilot plant at an existing Heidelberg Materials CDM recycling centre.

Conclusion

Alternative cement developers are still finding the words to talk about their products. They may be more than ‘supplementary’ up to the point of entirely supplanting 100% of clinker. Product webpages offer ‘hydraulic binder,’ ‘pozzolan’ and even ‘cement.’ As alternative ‘cements’ are developed, they build on the work of pioneers like Joseph Aspdin and Louis Vicat. Start-ups and their backers are now reaching commercial offerings, on a similar-but-different footing to cement itself. None of these novel materials positions itself as the sole, last-minute ‘super sub’ in the construction sector’s confrontation with climate change. Rather, they are a package of solutions which can combine into a net zero-emissions heavy building materials offering, hopefully before 2050.

Related to this is the need for ‘technology neutral’ standards, as championed this week by the Alliance for Low-Carbon Cement and Concrete (ALCCC), along with 23 other European industry associations, civil society organisations and think tanks. The term may sound new, but the concept is critical to the eventual uptake of alternative cements: standards, the ALCCC says, should be purely performance-based. They ought not attempt to define what technology, for example cement clinker, makes a suitable building material. According to the ALCCC, Europe’s building materials standards are not technology neutral, but instead ‘gatekeep’ market access, to the benefit of conventional cement and the exclusion of ‘proven and scalable low-carbon products.’

At the same time, cement itself is changing. Market research from USD Analytics showed an anticipated 5% composite annual growth rate in blended cement sales between 2024 and 2032, more than doubling throughout the period from US$253bn to US$369bn. If you can’t beat it, blend with it!

For a further discussion of alternative cement and binders in Europe, see Global Cement’s interview with ALCCC co-ordinator Joren Verschaeve in the forthcoming November issue of Global Cement Magazine on 17 October 2024.

US: Gabriel Carrero has taken on the role of Chief Commercial Officer (COO) at Carbon Limit, developer of the CO₂-sequestering concrete additive CaptureCrete. Carrero previously served as Senior Vice President, Sales & Marketing at fellow additive developer CarbonCure, and has held directorial roles in multiple companies in the cement and concrete chemicals innovation space, including working as COO of Sysdyne Technologies and NITROcrete and as Global Director, Specialty Construction Chemicals at GCP Applied Technologies. Carrero holds a Mechanical Engineering degree from the Centre Technological University (UNITEC) and an MBA from the University of Carabobo, both in Venezuela.

Finland/Netherlands/Sweden: Paebbl has commenced production of its carbon-storing cement using its new 100t/yr Obelix reactor. The company says that the trial represents a 100x scale up of its capacity in under six months. The Obelix reactor produces cement in 500l batches. Paebbl’s cement has a CO₂ storage capacity of 200kg/t. It expects to begin shipping samples to early adopter customers in the Benelux and Nordic regions from early 2024. The next scale-up for the company will come with the construction of a continuously operating pilot plant in late 2024, further increasing its cement capacity by a factor of 10.

UK: A team at Imperial College London has won a US$1.27m grant for its research into developing carbon negative cement from silica. The research won the Department for Energy Security and Net Zero (DESNZ)’s Carbon Capture, Usage & Storage (CCUS) Innovation 2.0 competition. The Imperial team sources its silica from natural olivine. It says that the compound behaves in the same way as other supplementary cementitious materials. Meanwhile, magnesia from the decomposition of the olivine can serve as a carbon sink in the form of magnesium carbonate. It, in turn, could serve as a raw material for concrete block production.

The DESNZ’s Net Zero Innovation Portfolio, of which the CCUS Innovation 2.0 competition is a part, has a budget of US$1.29bn.

UK: Denmark-based architecture fund Henrik Frode Obel Foundation has named Seratech as winner of its Obel Award 2022. The award recognises architectural contributions to global development. Seratech has developed an olivine-based composite cement produced using CO₂ from flue emissions, which can sequester double the CO₂ of ordinary Portland cement (OPC). When used as 40% of a blend with OPC, it is able to completely offset the emissions of concrete production.

Team member Barnaby Shanks said "The beauty of the idea is that you can just use it as normal concrete. There are other carbon-neutral materials, but they can be limiting because they can only be precast, cured in a lab in special conditions and shipped elsewhere. We want people to retain the freedom to use concrete the way that they are used to. We don’t want to limit people in any way because we’ll just lessen the amount of impact we can have."