Displaying items by tag: Calcined Clay

UK: Clay brick and concrete products producer Ibstock is seeking an industrial partner for a ‘major’ calcined clay cement plant in the UK.

The group has identified a large reserve of high-kaolin clay at one of its operating brick clay quarries in central England. The site is a fully-consented quarry, with sufficient calcinable material to support calcined clay production for more than 25 years. ‘Extensive’ drilling and industrial trials have been completed to confirm the reserves and the reactivity of the calcined clay for use in low-carbon cement production.

Ibstock says that is looking at an industrial partner to collaborate on the design, construction and commercialisation of the project. It is open to exploring optimal investment and partnership models to fully realise the potential of the site.

Email Ibstock to discuss the project: This email address is being protected from spambots. You need JavaScript enabled to view it.

US: Researchers at the Massachusetts Institute of Technology (MIT) have developed an AI tool to compare studies of alternative raw materials for cement production. A collaborative team from the MIT Concrete Sustainability Hub and MIT’s recycling research programme, Olivetti Group, published its findings in the Nature journal. The team mined 5.7m academic publications to identify 14,434 alternative raw materials. These belonged to 19 ‘types,’ including bottom ashes, fly ashes, calcined clays and slags, as well as less homogenous types such as biomass ashes, glasses and mine tailings. The study more than doubles the number of fly ashes and slags recorded on a database of this kind. The tool then provides a unified assessment of cementitious reactivity and pozzolanicity, also accounting for variables in particle size and amorphous content.

Ghana: CBI Ghana and joint venture partner Heidelberg Materials have commissioned the ‘world’s largest’ calcined clay plant in Ghana, according to an announcement by the German producer. The plant has a capacity of 400,000t/yr of calcined clay and uses local raw materials to reduce reliance on imported clinker.

Hakan Gurdal, member of the managing board of Heidelberg Materials, said “Based on calcined clay technology, we can now extend our offering of innovative, high-quality cement products, while reducing CO₂ emissions and utilising the rich local resources. The project has created over 300 local jobs."

Portugal: Cimpor will invest €155m in establishing a new research and development centre focused on sustainable construction, CO₂ reduction and digital transformation. The investment will also cover the modernisation of Kiln 7 at the producer’s Alhandra cement plant. The new centre will focus on technologies such as low-clinker cement development, carbon capture and alternative fuels, using recycled concrete and 3D printing. The building itself will incorporate calcined clay-based cement and recycled aggregates.

The new centre will create over 100 jobs and serve as a hub for collaboration with universities and startups, as well as serve as a location for conferences and workshops. The building will operate as a ‘living lab’, with real-time monitoring of its thermal and structural performance and energy consumption.

The chair of Cimpor Global Holdings, Suat Çalbiyik, said “In 2018, we operated only in Portugal and Cape Verde with around 1800 employees. Today, we are the world’s third-largest cement group… with 8000 employees in 14 countries and a production capacity of 112.5Mt/yr of cement.”

Ghana: CBI Ghana has invested US$100m in a new plant in Tema to produce limestone calcined clay cement (LC3) using local raw materials, to reduce reliance on imported clinker.

Commercial director of Supacem Kobby Adams said that the Ghana Standards Authority’s adoption of the GS PAS 5:2024 LC3 standard enabled the launch, following collaboration with local universities and international partners. According to Graphic Business news, the current clinker scarcity and its escalating prices stemmed from a 6% currency depreciation between December 2024 and February 2025 and the evolving global market uncertainties, including an increase in clinker export prices from the Mediterranean.

The project reportedly created over 160 direct jobs through local sourcing and infrastructure development in Tema and Torgome.

UK: LKAB Minerals and Forterra have partnered to produce recycled calcined clay from unwanted bricks as a traditional cement replacement, with production set to begin at LKAB’s Flixborough plant in Scunthorpe in June 2025. The material is made by crushing bricks sourced from Forterra’s Kings Dyke site in Peterborough.

LKAB Minerals UK managing director Steve Handscomb said “The traditional manufacturing and materials industries have to work harder than other less energy intensive industries, and need significant investments to upgrade equipment. We are committed to playing a role in the transition. In fact, we are already a significant producer of GGBS, and in our minerals division, 45% of the minerals we sell are from recycled sources or by-products.”

UK: The University of Sheffield, the Sellafield power station, the Nuclear Decommissioning Authority and the UK National Nuclear Laboratory have launched a €1.2m research partnership to explore the use of limestone calcined clay cement (LC3) in nuclear waste encapsulation. The project will study how characteristics and amounts of calcined clays can produce cement encapsulants that support safe and reliable nuclear waste conditioning and disposal at Sellafield.

Head of the Sheffield research team Brant Walkley said “This partnership will enhance our overall programme of work focused on development of new cement technologies for the nuclear sector, and will enable our cross-sector team based at both the University of Sheffield and Sellafield to further strengthen its position as a global leader in cement science and engineering.”

Northern-Ireland based cement producer Cemcor said this week that it has completed trials of a calcined clay cement product called CalcinX. The company started its trials in 2023 and it has been supported by Queen’s University Belfast and funding from Innovate UK. Work with commercial partners has involved precast concrete paving manufacturer Tobermore producing paviours made from 50% CalcinX as a CEM II replacement and Moore Concrete has also manufactured precast units using 50% CalcinX as a CEM I replacement. So far over 3000t of CalcinX has been produced in a number of industrial-scale trials.

David Millar, the managing director of Cemcor, mentioned his company’s plans for calcined clay in June 2022 when he was interviewed by Global Cement Magazine. The company that became Cemcor bought the Cookstown cement plant and a few other assets from Holcim at the start of 2022. It then changed its name to Cemcor in November 2022. At the time of the interview the company was looking to “...develop new value-added products, including low-CO₂ options. This will allow us to use the same amount of clinker to produce more cement.” Millar couldn’t give away too many details at the time, however calcined clay was cited specifically. It was also noted that the company had the right material in its quarry and that it was already working with partners on it.

Amongst all the other decarbonisation options available for cement plants, a slow trickle of calcined clay projects keep being announced. In January 2025, for example, thyssenkrupp Polysius said it had secured a front-end engineering design contract from Circlua for the construction of the world’s largest activated clay plant in Brazil. This project in Para state will have a capacity of 3000t/day, will use renewable energy sources and will “improve the CO₂ footprint in cement production.” CBMI Construction also officially launched a flash calcination clay project in Tangshan, Hebei province in China. In December 2024, Vicat signed an agreement with the US Department of Energy (DOE) Office of Clean Energy Demonstrations to develop the Lebec Net Zero (LNZ) project at its Lebec cement plant in California. This includes plans to produce calcined clay-based cement. Earlier in the autumn of 2024 Portugal-based Cimpor said it was preparing to convert a kiln at its Souselas plant to produce calcined clays, AVIC International Beijing and KHD said that they had secured a deal to build a 900t/day clay calcination plant for Ciments de l'Afrique (CIMAF) in Burkina Faso, and Holcim Česko said it was going to construct a calcined clay processing line at the Čížkovice cement plant in the Czech Republic.

One news story that stuck out in the autumn was the progress of a collaboration between Aumund and Holcim towards developing an electric linear calcination conveyor (eLCC). The two companies started work on the project in 2020 intending to look at the electrical calcination of clay using an Aumund pan conveyor. Initial tests of the eLCC reportedly demonstrated efficient thermal activation of clay through a combination of radiant heat and material circulation. The eLCC system is fully enclosed, insulated, has a compact design and can operate using electrical-powered renewable sources. The first industrial plant utilising this technology is scheduled for construction in 2025. Calcined clay technology and products by other industrial suppliers are available. The work by Aumund and its competitors show they are watching this market closely.

OneStone Consulting’s Joe Harder has found that only 14 clay calcination plants were operational worldwide in 2023 with a production capacity of just under 3.5Mt/yr. These are based in Latin America, Europe and Africa. In an article previewing a market report in the February 2025 issue of Global Cement Magazine, Harder predicts that by 2035 there will be 79 clay calcination plants with a capacity of just under 21Mt/yr. A steady growth of over 20 new plants annually is also expected subsequently from 2035 to 2050 as cement producers seek cost-effective ways to reduce their clinker factor. He identified installation costs, a lack of knowledge about clay-based cements, trouble obtaining mining rights and policy issues amongst other issues as holding back the use of clay calcination.

The current expectation is that calcined clay usage in the cement industry will be a minority option. Yet the size of global cement production can make a production share of, say, 3 - 8% a viable option for both cement manufacturers and equipment suppliers. The adoption of new cement products and standards can also take a long time and this clouds predictions of how far clay can go in the cement industry. At this point in the calcined clay story it is time to keep track of the new projects being set up.

Joe Harder will present a talk entitled ‘Calcined clay market trends by 2035’ at the Global FutureCem Conference taking place in Istanbul in early February 2025

Brazil: thyssenkrupp Polysius has secured a front-end engineering design contract from Circlua for the construction of the world’s largest activated clay plant, with a capacity of 0.96Mt/yr (3000t/day). The plant will be largely powered by renewable electricity, and will be located in Pará, utilising clay sourced from the Carajás iron ore complex. The clay contains up to 80% kaolinite content, and will be upcycled as supplementary cementitious material.

thyssenkrupp Polysius CEO Christian Myland said “We are honoured to partner on this landmark project. Leveraging high-quality local clay and our advanced activated clay technology, this plant will set a new benchmark for carbon-conscious cement production.”

US: Vicat subsidiary National Cement Company of California has signed a cooperative agreement with the US Department of Energy (DOE) Office of Clean Energy Demonstrations to develop the Lebec Net Zero (LNZ) project at its Lebec cement plant in California.

The agreement commits up to US$500m, covering up to 50% of the Phase one cost. The project includes constructing a CO₂ sequestration facility with a 0.95Mt/yr capacity, enabling the plant to capture ‘almost all’ of the plant’s emissions. It will also increase alternative fuel use from locally sourced biomass and reduce the plant’s clinker factor by producing calcined clay-based cement. The plant will reportedly produce carbon-neutral cement.

The first step will be to conduct a preliminary engineering study and establish a community advisory body in charge of relations with local communities. Phase one will run through the first quarter of 2026.