Displaying items by tag: Calcined Clay

Ghana: Heidelberg said that it has signed an agreement with CBI for the acquisition of 50% of the latter’s shares. CBI is the parent company of CBI Ghana, which operates the 0.6Mt/yr Tema grinding plant in Accra. It is in the process of establishing a calcined clay plant at the facility. HeidelbergCement says that it and CBI will explore the possibility of further calcined clay projects in West Africa. Other investors in CBI Ghana include Denmark-based Investeringsfonden for Udviklingslande (IFU) and Norway-based Norfund.

HeidelbergCement’s existing Ghanaian susbidiary Ghacem operates 3Mt/yr-worth of grinding capacity at two plants in Accra and Takoradi.

HeidelbergCement managing board member Hakan Gurdal said “Characterised by high sustained market growth rates, Ghana is one of HeidelbergCement’s core markets in Africa. The new flash calciner in Ghana will be the largest worldwide, with a calcined clay production capacity of more than 400,000t/yr. Start of production is planned for 2024.” Gurdal concluded “We are committed to lowering our CO₂ footprint also in emerging markets.”

Denmark: FLSmidth has formed a partnership called ECoClay to develop and commercialise the technology needed to electrify the calcination of clay used in cement production. The partners include the Danish Technological Institute, US-based industrial heating specialist Rondo Energy, France-based Vicat, Colombia-based Cementos Argos and the Technical University of Denmark. The project is partly funded by the Energy Technology Development and Demonstration Program (EUDP) under the Danish Energy Agency.

The use of calcined clay in cement production allows cement producers to replace up to 30% of limestone-based clinker, resulting in up to 40% lower CO₂/t in cement produced. By electrifying the process, ideally powered by renewable sources, the ECoClay partnership expects to further reduce emissions by 10% at more uniform conditions that allow processing of a broader range of raw clays.

Based on the shared research and tests on high-temperature electric heat generation, storage solutions and renewable grid integration, the ECoClay partnership will build a pilot plant at FLSmidth’s research and development centre in Denmark. The consortium will seek to demonstrate how the ECoClay process is superior to the conventional combustion processes, has a smaller physical footprint on site and significantly lower emissions of air pollutants. According to the project plan, the ECoClay partners expect to be able to commence construction of the first full-scale electric clay calcination installation by the end of 2025.

Ghana: Denmark-based Investeringsfonden for Udviklingslande (IFU) and Norway-based Norfund have invested US$27.9m in CBI Ghana. The funding will support the cement producer’s upgrade of a clay calcination unit at its 0.6Mt/yr Tema grinding plant in Accra. Denmark-based FLSmidth is supplying the equipment for the project.

African cement producers have confirmed their interest in calcined clay over the last month with two new projects. The big one was announced last week when FLSmidth revealed that it had received an order from CBI Ghana. This follows the launch of a Limestone Calcined Clay (LC3) project in Malawi in mid-March 2022 in conjunction with Lafarge Cement Malawi.

FLSmidth says that its order includes the world’s largest gas suspension calciner system and a complete grinding station. The kit will be installed at CBI Ghana’s plant near Accra in the south of the country. The new clay calciner system is expected to substitute 30 - 40% of the clinker in the final product, resulting in a reduction of up to 40% CO₂/t of blended cement compared to Ordinary Portland Cement (OPC). Overall the equipment manufacturers reckon that the grinding plant will reduce its CO₂ emissions by 20% compared to its current output. There has been no indication of how much the order costs but CBI Ghana expects energy and fuel savings, as well as lower overheads from clinker imports.

The public announcement of the Ghana project was also foreshadowed by the visit of Professor Karen Scrivener to the Ghana Standards Authority in February 2022. This was significant because Scrivener is the head of the Laboratory of Construction Materials at the Ecole Polytechnique Fédérale de Lausanne (EPFL) and has been one of the key instigators of the LC3 initiative since the early 2000s. Other calcined clay cements are available such as Futurecem or polysius activated clay (see below) but LC3 is arguably the most famous given its promotion in developing countries.

The Malawi project is at a much earlier stage. The government launched the public private partnership LC3 project in mid-March 2022 in conjunction with Lafarge Cement Malawi and Terrastone, a brick manufacturer. The Ministry of Mining is currently developing a memorandum of understanding with the Gesellschaft für Internationale Zusammenarbeit (GIZ), a Germany-based development agency. India-based Tara Engineering has also been linked to the scheme.

One thing to note about the Malawi project is that it is the first calcined clay project in the cement industry based in East Africa. All the other African ones are based in West Africa. The other two projects in this region are run by Turkey-based Oyak Çimento and its subsidiary Cimpor. The first of these is a 0.3Mt/yr calcined clay and a 2400t/day cement grinding production line that was commissioned in mid-2020. This plant is based at Abidjan in Ivory Coast. The second is a new plant that Germany-based ThyssenKrupp Industrial Solutions is building for Oyak Çimento at Kribi in Cameroon. This unit has a 720t/day calcined clay and a 2400t/day cement production capacity and it will use the supplier’s ‘polysius activated clay’ technology. ThyssenKrupp’s involvement came to light in early 2020 and commissioning was scheduled for late 2021. However, no update on the state of the project has been issued so far in 2022.

As the above examples show, Sub-Saharan Africa has at least one live calcined clay plant, two plants are being built and there’s one more at the development stage. This puts the region neck-and-neck with Europe, which has a similar mixture of current and developing projects. This column has been covering the wider trend of the growing usage of various types of blended cements recently, particularly in Europe and the US, with slag cements, Portland Limestone Cement (PLC) and more. With PLC, for example, note the transition of another two North American cement plants to PLC this week alone. As for calcined clay cement, it is fascinating to see the focus move to a different part of the world. Several commentators have predicted that the future looks set to be dominated by blended cements using whichever supplementary cementitious material (SCM) is most available for each plant. The growth in calcined clay confirms this view.

Global Cement is researching clay calcination use in the cement industry for the next edition of the Global Cement Directory. Email This email address is being protected from spambots. You need JavaScript enabled to view it. with any information on new industrial and research installations.

Malawi: The Germany-based Gesellschaft für Internationale Zusammenarbeit (GIZ) has launched the construction of a clay calcination plant in Malawi, called the Limestone Calcined Clay Project. The Nyasa Times newspaper has reported that the government has said that increased calcined clay use can reduce domestic cement production’s carbon footprint by a third.

Ghana: FLSmidth has secured a contract for the supply of a clay calcination plant at CBI Ghana's 0.6Mt/yr Tema grinding plant in Accra. The supplier says that it will also install a complete grinding station to more than double the plant's production capacity. FLSmidth says that the entire project will reduce the Tema facility's CO₂ footprint by 20%. When commissioned, the new clay calcination plant will be the largest in the world, according to the supplier.

CBI Ghana chief executive officer Frédéric Albrecht said “Ghana is the perfect location for using clay as an environmentally friendly alternative to clinker. West Africa is traditionally a clinker and cement-importing region due to the lack of suitable limestone reserves. Developing countries with their young populations and a growing need for infrastructure and housing represent the future in cement consumption. Calcined clay cements are the most sustainable alternative to traditional clinker-based cement."

From the Nordics to the Mediterranean, European countries lead the field in reduced-clinker cement production using supplementary cementitious materials (SCMs). While consumers, faced with ever-greater choice, continue to opt for sustainability, projects to improve existing SCMs and develop new ones have won government backing and have become a matter of serious investment for other heavy industries beside cement. European cement producers’ decisions are steering the course to a world beyond CEM I. Yet, even in Europe, great untapped potential remains.

Companies generated a good deal of marketing buzz around their latest reduced-CO₂ cement ranges in 2021 and the first quarter of 2022: Buzzi Unicem’s CGreen in Germany and Italy, Holcim’s EcoPlanet in six markets from Romania to Spain, Cementir Holding’s Futurecem in Denmark and Benelux, and Cemex’s Vertua in Spain and several other countries. All boast reduced clinker factors through the use of alternative raw materials. This, however, is really a rebranding of a long-established norm in Europe.

Since 2010, cements other than CEM I have constituted over 75% of average annual cement deliveries across Cembureau member countries (all cement-producing EU member states, plus Norway, Serbia, Switzerland, Turkey, the UK and Ukraine). This statistic breaks down differently from country to country. CEM II is the norm in Austria, Finland, Portugal and Switzerland, with deliveries in the region of 90%. Portland limestone cement (PLC) makes up a majority of deliveries in all four. It has been central to Switzerland’s transition to 89% (3.72Mt) of CEM II deliveries out of a total 4.18Mt of cement despatched in 2021. There, the main types of cement were CEM II/B-M (T-LL) Portland composite cement, with 1.38Mt (33%), and two different classifications of PLC: CEM II/A-LL PLC, with 1.28Mt (31%), and CEM II/B-LL PLC, with 888,000t (21%).

A second approach is that of the Netherlands, where CEM III blast furnace slag cement with a clinker factor below 65% predominates, favoured for its sulphate resistance and the protection it offers against chloride-initiated corrosion of steel reinforcement in marine settings. By contrast, the UK has traditionally maintained a higher reliance on CEM I cement. This can be partly explained by the preference of builders there for adding fly ash or ground granulated blast furnace slag (GGBFS) at the mixing stage. Nonetheless, CEM II Portland fly ash cement held a 14% (1.43Mt) market share in the UK’s 10.2Mt of cement consumption in 2021.

The UK Mineral Products Association (MPA) has identified limestone as an underutilised resource in the country’s cement production. Together with HeidelbergCement subsidiary Hanson Cement, it has applied for a change to National Application standards to allow the production of Portland composite cement from fly ash and limestone or GGBFS and limestone. The association has forecast that Portland composite cement could easily rise to 30 – 40% of UK cement consumption, and that this has the potential to eliminate 8% of the sector’s 7.8Mt/yr-worth of CO₂ emissions.

Metallurgical waste streams have long flowed into European cement production, primarily as GGBFS, but also as bauxite residue. In 2021, alumina production in the EU alone generated 7Mt of bauxite residue, of which the bloc recycled just 100,000t (1.4%) that year. Two projects – the Holcim Innovation Center-led ReActiv project and Titan Cement and others’ REDMUD project – aim to produce new alternative cementitious materials from bauxite residue.

By collaborating with other industries, cement producers’ investments can most effectively reduce the overall cost of using these materials in cement production. In Germany, HeidelbergCement and ThyssenKrupp’s Save CO₂ project aims to develop new improved latent hydraulic binders or alternative pozzolan from GGBFS by producing slag from directly reduced iron (DRI). The Save CO₂ team believes that GGBFS substitution for clinker has the capacity to eliminite 200Mt/yr of CO₂ emissions from global cement production.

Meanwhile in the world of mining, ThyssenKrupp and others’ NEMO project is investigating the recovery of a useable mineral fraction for cement production from the extractive waste of the Luikonlahti and Sotkamo mines in Finland and the Tara mine in Ireland, through bioleaching and cleaned mineral residue upcycling. This may give cement producers full access to Europe’s 28Bnt stockpiles of sulphidic mining waste, of which mines generate an additional 600Mt each year.

Denmark-based CemGreen, which produces the calcined clay supplementary cementitious material CemShale, is developing a shale granule heat-treating technology called CemTower. This consists of three pieces of equipment vertically integrated into cement plants’ preheaters, kilns and coolers, and brings the processing of waste materials – here oil shale – to the cement plant.

Lastly, cement producers are exploring the possible uses of waste made of cement itself. In Wallonia, HeidelbergCement subsidiary CBR’s CosmoCem project is investigating the production of alternative cement additives from large available flows of local demolition, soil remediation and industrial waste. Similarly, the Greece-based C2inCO₂ project seeks to mineralise fines from concrete recycling for HeidelbergCement to use in the production of novel cements in its Greek operations.

In Switzerland, ZND Portland composite cement (produced using fine mixed granulate from building demolitions) is the third largest cement type, with 178,000t (4.3%) of total deliveries – narrowly behind CEM I with 239,000t (5.7%).Holcim Schweiz developed its Susteno 4 ZND Portland composite cement with Switzerland’s lack of any ash or slag supply in mind, demonstrating the potential flexibility of a circular economic approach to cement production.

On 21 March 2022, the University of Trier reported that it is in the process of mapping mineral resources, waste deposits and usable residues ‘on a cross-border scale,’ in an effort to produce new materials for use in cement production. Industry participants include France-based Vicat, CBR, Buzzi Unicem subsidiary Cimalux and CRH subsidiary Eqiom. Vicat is preparing a kiln at its 1Mt/yr Xeuilley cement plant in Meurthe-et-Moselle to use in testing new alternative raw materials developed under the project.

For Cembureau and its members, work continues, with the goal of Net Zero by 2050 constantly in sight. This goal includes a reduction in members’ clinker-to-cement ratios to well below 65%. In this, the association and its members are working towards a world not just beyond CEM I, but beyond CEM II, too. What exactly this will mean remains to be seen.

Sources

CemSuisse, ‘Lieferstatistik,’ 11 January 2022, https://www.cemsuisse.ch/app/uploads/2022/01/Lieferstatistik-4.-Quartal-2021.pdf

WSA, ‘December 2021 crude steel production and 2021 global crude steel production totals,’ 25 January 2022, https://worldsteel.org/media-centre/press-releases/2022/december-2021-crude-steel-production-and-2021-global-totals/

MPA, ‘Low carbon multi-component cements for UK concrete applications,’ July 2018, https://prod-drupal-files.storage.googleapis.com/documents/resource/public/Low%20carbon%20multi-component%20cements%20for%20UK%20concrete%20applications%20PDF.pdf

European Commission, ‘European Training Network for Zero-waste Valorisation of Bauxite Residue (Red Mud),’ 16 July 2020, https://cordis.europa.eu/project/id/636876

European Commission, ‘Industrial Residue Activation for sustainable cement production,’ 16 February 2022, https://cordis.europa.eu/project/id/958208

Recycling Portal, Zement der Zukunft – Forschungsprojekt „SAVE CO₂“ gestartet, 28 May 2021, https://recyclingportal.eu/Archive/65677

h2020-NEMO, ‘Project,’ https://h2020-nemo.eu/project-2/

European Commission, ‘Green cement of the future: CemShale + CemTower,’ 14 April 2021, https://cordis.europa.eu/project/id/101009382

CosmoCem, ‘Communiqué de Presse,’ https://cosmocem.org/

CO₂ Win, ‘C²inCO₂: Calcium Carbonation for industrial use of CO₂,’ https://co2-utilization.net/en/projects/co2-mineralization/c2inco2/

Les Echos, ‘Rendre le ciment moins gourmand en CO₂,’ 21 March 2022, https://www.lesechos.fr/pme-regions/innovateurs/des-substituts-au-clinker-rendent-le-ciment-moins-gourmand-en-co2-1395002

Benelux/France: Cementir Holding has introduced its Futurecem limestone calcined clay cement into the Benelux and French cement markets. Futurecem cement applies Cementir Holding’s patented processes to substitute over 35% of clinker in cement with limestone and calcined clay, preserving the cement’s strength and quality while reducing its carbon footprint by 30% compared to ordinary Portland cement (OPC).

Cementir Holding previously rolled out Futurecem cement in Denmark in 2021. In 2022, it plans to launch InBind high performance concrete (HPC) and ReCover ultra-high performance concrete (UHPC) to expand its range of HPC and UHPCs using Futurecem technology.

Eddy Fostier, managing director of Cementir Holding’s Belgian subsidiary CCB, said “Thanks to the joint efforts of the group and CCB teams, Futurecem technology is the main pillar for CCB’s low carbon transition within the Group roadmap. This product technology is matching customer needs, highlighted through a specific survey carried out across the most relevant market areas and applications.” Fostier concluded “I’m fully convinced that Futurecem will play a relevant role in the decarbonisation of the construction industry, where cement and concrete are essential building materials both in the present and in the future.”

Italy: Cementir’s revenue grew by 11% year-on-year to Euro1.36bn in 2021 from Euro1.22bn in 2020. Its earnings before interest, taxation, depreciation and amortisation (EBITDA) grew by 17.9% to Euro311m from Euro264m. Sales volumes of cement and concrete increased by 4.1% to 11.2Mt and 14.8% to 5.01Mm3 respectively.

“2021 marked for Cementir the year of the historic record of revenues and EBITDA despite the uncertainties related to the pandemic crisis, the substantial increase in energy costs, materials and services and the devaluation of the Turkish lira,” said Francesco Caltagirone Jr, chair and chief executive officer of Cementir.

The group also reviewed and approved the three-year Group Industrial Plan update for the period 2022 - 2024 and the 2022 budget. It has a target of reduce CO₂ emissions (scope 1) by 30% in 2030 compared to 1990 levels. It is also planning to invest Euro116m in the 2022 – 2025 to meet this goal and others. Some of this will go towards building a new production line at its integrated Gaurain cement plant in Belgium, where the work is intended to raise the unit’s alternative fuels substitution rate to 80% from 40%. The group noted that this project has been delayed to 2022 due to the coronavirus pandemic. Changes at other cement plants include switching to natural gas and biogas as well as energy efficiency projects. It is also said it was planning to ‘significantly’ increase the production of its FUTURECEM calcined clay cement and related sustainable products.

Ghana: Professor Karen Scrivener has paid a working visit to the Ghana Standards Authority (GSA). The visit was part of a tour by Scrivener to Ghana to discuss innovations in cement and cementitious products and to introduce Limestone Calcined Clay Cement (LC3) to the authority, according to the Ghana News Agency. The Head of Laboratory of Construction Materials at the Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland met with GSA management and staff of the Building and Civil Engineering Lab at the Authority's Head Office in Accra. Scrivener noted that she was interested in learning more and engaging with the GSA on standards and its testing capabilities as well as a potential collaboration in capacity building in cement and cementitious products.