Displaying items by tag: Fly Ash

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

Indonesia: Conch North Sulawesi Cement is receiving 50t/day of fly and bottom ash from the Amurang coal-fired power plant in North Sulawesi. Koran Metro News has reported that the Semen Conch subsidiary uses the ash as a supplementary cementitious material (SCM) in its cement production. The Amurang power plant currently holds 80,000t of the byproduct in stockpiles.

UK: Hercules Enterprises plans to establish an up to 0.5Mt/yr grinding plant at Sheerness on the Isle of Sheppey in Kent, according to Kent Online News. The plant would comprise two clinker grinding lines, a mobile ecohopper, a mechanical transport system for transfer of material into storage, a 47,000m³ clinker storage hall, six 3000m³ cement silos, three 3000m³ fly ash silos, two packing plants and a palletising hall.

Australia: Boral’s earnings in the first half of its financial year have fallen as it has completed the sales of its North American fly ash business. Its revenue from continuing operations fell slightly to US$1.08bn in the six months to 31 December 2021. However, its earnings before interest, taxation, depreciation and amortisation (EBITDA) for continuing operations dropped by 16% to US$138m from US$164m in the same period in 2020. Cement and concrete sales volumes remained stable and rose slightly respectively.

“With the completion of the divestment of our North American Fly Ash business on 11 February 2022, we have now finalised the strategic realignment of our portfolio to focus on our Australian construction materials business,” said Boral’s chief executive officer Zlatko Todorcevski. “We are focused on building a more competitive and profitable business that is positioned for success and delivers increased returns to shareholders.” He blamed falling earnings on construction shutdowns and growing energy prices despite changes to the business.

US: Eco Material Technologies has successfully completed its acquisition of near-zero carbon cement alternatives producer Green Cement. Eco Material Technologies previously agreed to acquire Boral’s US fly ash business in December 2021, a transaction which it expects to conclude in 2022.

US: Eco Materials Technologies has finalised its US$1.05bn acquisition of Boral’s US fly ash business and launched an oversubscribed US$525m green bond issue. The issue will help it to become a global green cement production leader, according to the group. The Australian Financial Review newspaper has reported that subscriptions were four times the available bonds.

US: Ash Grove Cement has re-opened its Port Manatee terminal in Florida following the installation of a new Kovako type ship unloader supplied by FLSmidth. The machine was custom built for Ash Grove by the Denmark-based company to meet its specific needs. The cement producer says it is the largest mobile pneumatic ship unloader built, has twin 800hp blowers, 37m suction arm and can offload a dry bulk vessel at a high rate while maintaining maximum efficiency and minimising environmental impact by eliminating dust emissions.

A ribbon-cutting ceremony to celebrate the event was held on 7 February 2022 as a shipment of fly ash was processed at the site. This maiden shipment completes the Phase 1 transformation project at Port Manatee, which began in early 2021. The project is intended to improve the subsidiary of CRH’s capacity to import cement, slag and fly ash for customers in Florida and South Georgia. It is also planning to use the terminal’s existing silo capacity to complement the capabilities of Ash Grove’s cement plants in Sumterville and Branford.

India: Birla Corporation has started the kiln at its new 3.9Mt/yr Mukutban cement plant at Nagpur in Maharashtra. The project had an investment of around US$370m and the plant will be run by subsidiary RCCPL. Birla Corporation said that the new plant is the group’s fourth integrated plant and the biggest single cement production line in Maharashtra by capacity. It will be powered by two 20MW captive power plants that use air-cooled condenser technology to reduce water consumption by 90%. The plant was partly built using the group’s MP Birla Cement Perfect Plus product, a Portland Pozzolana Cement, composed of 30 - 35% fly ash, itself a by-product of thermal power plants. Use of fly ash and slag will be scaled up at the site as production ramps up.

“It is no mean feat to complete such a large project under such challenging circumstances with major disruptions on account of Covid-19 which led to several logistical challenges, stoppage of work and a flight of labour from the project site on several occasions,” said Harsh V Lodha, the chair of Birla Group. “Moreover, to achieve 10m man hours of construction with zero accidents and completion of the entire project without a single major accident or fatality, I am told, is a unique achievement in the cement industry.”

Finland: Betolar has announced the commencement of trading in its shares on the Nasdaq Helsinki exchange. Betolar launched its Geoprime alkali-activated slag and fly ash-based concrete additive in September 2021.

Tero Ojanperä, chair of Betolar’s board of directors, said “The company has so far been developed with a strong ownership with the aim of creating a significant position for Betolar in the global cement market. The share issue expands our shareholder base and provides a significant capital injection to accelerate Betolar's internationalisation.” He continued “The oversubscription of the share issue signals the market's strong belief that effective market-based solutions to the climate crisis can be found. We thank all the retail and institutional investors who participated in the share issue for their trust."

CEO Matti Löppönen added “The outstandingly successful share issue provides Betolar’s executive management with a supportive mandate to start promoting the green transition in various industries globally. At the same time, it also obliges us to steer the company in line with our strategy, in which trust is constantly strengthening among shareholders and customers, as well as society decision-makers.” He concluded “The Betolar team is strongly committed to taking the growth company to the next level.”

US: Australia-based Boral has agreed to sell its US fly ash business to Eco Material Technologies for US$755m. The parties expect to conclude the transaction by the start of 2023. The proceeds of the sale will add to Boral’s surplus capital.

Boral’s chief executive officer Zlatko Todorcevski said “Together with the sale of our North American building products business and our stake in Meridian Brick, we will have divested the North American businesses for more than US$3bn.” He added “This is a significant milestone that supports our strategy to refocus on our construction materials business in Australia.”