Displaying items by tag: supplementary cementitious materials

Switzerland: The latest report from the Intergovernmental Panel on Climate Change (IPCC) has informed policymakers that the best current route to reduce carbon emissions from cement production is through the increased use secondary cementitious materials and by encouraging the development and uptake of carbon capture. Alternatively, the development of new chemistries for building materials could help the situation but this is not expected in the short to medium term.

The report noted that 12Gt of CO₂ equivalent was released directly and indirectly in 2019 from buildings and emissions from cement and steel use for building construction and renovation. These emissions included indirect emissions from offsite generation of electricity and heat, direct emissions produced onsite and emissions from cement and steel used for building construction and renovation. In sections of the IPCC report yet to be finally approved the authors said, “Cement and concrete are currently overused because they are inexpensive, durable, and ubiquitous, and consumption decisions typically do not give weight to their production emissions.”

Overall, the report concluded that average annual global greenhouse gas emissions from 2010 to 2019 were at their highest levels in human history but the rate of growth had slowed. The IPCC has called on “immediate and deep emissions reductions across all sectors” for any chance for society to limit global warming to 1.5°C. To do this global greenhouse gas emissions would have to peak before 2025 at the latest and be reduced by 43% by 2030. However, even if this did occur, it would take until the end of the 21st century for the temperature threshold to be stabilised.

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.

US: Cementos Argos subsidiary Argos Florida Cement has won the Slag Cement Association (SCA)’s Durability and Infrastructure awards at its 2022 Sustainable Concrete Project of the Year Awards. The producer won the awards for its supply of slag cement to two projects in Florida in 2021. Its involvement in the American Bridge Company’s SR 679 Pinellas Bayway Bridge – Structure E replacement won it the Durability award, while its involvement in Superior Paving’s State Road 52 realignment. Argos Florida Cement congratulated its customers, who also received the awards.

World: Market Research Future has forecast a 15% composite annual growth rate (CAGR) in global green cement demand between 2018 and 2023, where green cement is defined as fly ash cement, slag cement, geopolymer cement and other cements produced using alternative raw materials. Market Research Future predicts that fly ash cement’s global growth will be the sharpest due to its abundant availability. Its report concluded that cement sector strategies in response to the growth would include mergers, joint ventures and acquisitions.

UK: Concrete admixture producer Oscrete UK has appointed Matthew Gabriel to the role of new product development and sustainability manager. The company says that the appointment strengthens its commitment to sustainable construction.

Gabriel said “With the environment at the forefront of everyone’s minds, and customers looking to increase their use of supplementary cementitious materials (SCM), my priority is to develop products and processes which support our customers’ own route towards low carbon concrete.” He continued “Finding cost effective green solutions without impacting performance is key to the future of the construction sector. We are now looking to develop products that can help our customers to use or increase the use of products with a lower eCO₂, hence the creation of a role dedicated entirely to this arena.”

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

France: Vicat plans to use a kiln at its 1Mt/yr Xeuilley, Meurthe-et-Moselle, cement plant for trials of cement production using new alternative raw materials developed under the international CO₂Redres supplementary cementitious materials (SCM) project. The project brings together Vicat, HeidelbergCement subsidiary CBR, Buzzi Unicem subsidiary Cimalux and CRH subsidiary Eqiom in an effort to map mineral resources, waste deposits and usable residues ‘on a cross-border scale.’ On the basis of this research, the partners will seek to develop new SCMs for use in cement production.

Philippines: Big Boss Cement has reportedly suspended business operations until 2022. An unnamed source at the company quoted by the Philippine Daily Inquirer newspaper said that the company is ‘rehabilitating’ its facilities. It added that the company is using a lull in business to make changes.

The company was set up by SM Group heir Henry Sy Jr in 2018. It opened a grinding plant at Porac in Pampanga, Luzon in 2018 and commissioned a third mill at the site in late 2020. Notably the unit manufactures its own secondary cementitious material, which it calls Granulated Activated Sand by Heating, as well as importing clinker and other raw materials.

Canada: Progressive Planet Solutions has appointed Randy Gue and Chris Halsey-Brandt to its advisory board. The company is developing pozzolan-based supplementary cementitious material (SCM) products. It operates its Z1 Zeolite quarry in Cache Creek, British Columbia and is working on other projects also in the province.

Gue will advise on introducing Progressive Planet's developing products into the marketplace with the initial focus on markets for PozGlass SCM. Randy spent 17 years with Lafarge Canada as the Director of Business Development and Resource Recovery where he led Lafarge's Western North American initiative to reduce variable operating costs by developing business-to-business relationships primarily related to the recovery and reuse of wastes and by-product streams from industries and institutions.

Halsey-Brandt will assist in financial analysis of the first PozGlass SCM manufacturing plant and will also assist in evaluating opportunities to grow the company through strategic acquisitions. He is both a chartered professional accountant (CPA) and a chartered business valuator (CBV). At present Halsey-Brandt owns and operates a successful food processing business. Prior to becoming an entrepreneur, he was a partner at Blair Mackay Mynett Valuations, an independent firm in Vancouver providing business valuation services.

US: Solidia Technologies has filed a patent for a new hydraulic cement consisting of Ordinary Portland Cement (OPC) and other supplementary cementitious materials (SCM) including lime, alkali hydroxides, clay minerals and over 10% synthetic pozzolan.

Solidia Technologies said, “In order to reduce global CO₂ emissions it is necessary to adopt new approaches to create a new generation of hydraulic cements. The most efficient cement kiln can produce OPC clinker with an associated emission of 816 kg of CO₂/t. Blending the ground cement clinker with SCM, which have low or zero associated production CO2 emissions, reduces the total embodied CO₂ of the final product. Using a cement with the lowest possible clinker factor for a given application is the most common industry approach to reducing the CO₂ footprint of concrete.”