Displaying items by tag: Clinker factor

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.

Philippines: Taiheiyo Cement Philippines has inaugurated a new US$220m production line at its plant in San Fernando, Cebu, which is expected to support national cement production and reduce reliance on imports. The plant now has a capacity of 3Mt/yr, or 6000t/day of clinker. The new production line replaced the old facility, which was demolished in 2021. The facility incorporates kiln renewal technology that reportedly cuts CO₂ emissions by at least 10% through reduced energy consumption and a lower clinker factor. San Fernando Mayor Mytha Ann Canoy said the new facility is expected to generate 2000 new jobs.

France: The Eqiom Lumbres cement plant, part of CRH, has commissioned ThyssenKrupp Polysius to construct a fine grinding plant. The new plant will include the Polysius booster mill and the Sepol ultra-fine classifier, along with necessary auxiliary equipment. ThyssenKrupp Polysius is set to deliver the equipment by late summer 2025, aiming for commissioning in the fourth quarter of 2025. It will also provide on-site service and technical support for performance optimisation.

Project Manager Layal Haddad said "We are proud to be contributing to decarbonisation with the ultra-fine grinding plant and reducing the CO₂ footprint of cement. This is the first ultra-fine grinding plant based on a Polysius booster mill to be sold worldwide. We look forward to a successful project together with the Eqiom/CRH team."

China: A new study from Hong Kong Polytechnic University showcases sustainable cement production methods, focusing on low-clinker cements and alternative solutions for incinerator fly ash (IFA). The research demonstrates that using carbonated-washed IFA mixed with slag, coal fly ash, or metakaolin can replace 60% of Portland cement, forming ternary blended cement. This approach reportedly reduces the carbon footprint of cement production.

The study found that slag was the most effective, improving pore structure and increasing ettringite and hemicarboaluminate formation with a blend of 40% slag and 20% IFA. It achieved 90% of the compressive strength of pure Portland cement after 90 days.

The researchers said "This study demonstrated the promising potential of the blended cements to simultaneously divert IFA from landfills and reduce the clinker content of cement."

Brazil: Votorantim Cimentos has made progress in reducing its carbon footprint, reporting embodied CO₂ emissions of 556kg/t of cement produced in 2023, a 4% year-on-year decrease. The company aims to reach a target of 475kg of CO₂/t by 2030, aligning with the Science Based Target initiative standards.

The company's decarbonisation strategy involves four stages: co-processing, which involves substituting fossil fuel with biomass and waste; use of cementitious materials to replace clinker; enhancing energy efficiency and use of renewable energy; and developing new technologies and materials, including carbon capture. In 2023, Votorantim Cimentos achieved a 31% global thermal substitution rate through co-processing, an increase from 26.5% in 2022, with a goal of reaching 53% by 2030. The clinker factor was reduced to 72.8% in 2023 from 73.9% in 2022. This reduction means a decrease in emissions, with a target clinker factor of 68% set for 2030. Additionally, 35.1% of the electricity consumed by Votorantim Cimentos in 2023 came from renewable sources, an increase from 22.9% in 2022, with an aim of 45% by 2030.

Álvaro Lorenz, global director of sustainability, institutional relations, product development, engineering, and energy at Votorantim Cimentos, said "The most competitive and sustainable companies will be those with the lowest emissions. In all countries where we operate, we are committed to advancing in our decarbonisation journey, in line with our goal of producing carbon-neutral concrete by 2050."

Votorantim Cimentos’ environmental efforts were recognised with an A score by CDP and a Top-Rated Industry company distinction by Sustainalytics in the Latin American building materials sector. The company also announced a US$989m investment to further reduce its CO₂ emissions. This includes a project at Salto de Pirapora to increase thermal substitution, with expected completion by 2028. Votorantim Cimentos has also started constructing a solar energy complex in Paracatu, with an estimated capacity of 470MWp.

France: Ecocem has launched a new low-carbon advanced cement technology (ACT) cement, aiming for widespread adoption in European construction projects. The ACT range promises a clinker concentration of 20%, lower than the current norm of 35% minimum.

Jean-Christophe Trassard, Director, Marketing of Sustainable Innovation, said "We achieve competitive rates by controlling granularity, the fineness of grinding and admixtures. We have also greatly developed our thinking on the addition of additives in our formulations, which required more than fifteen years of R&D and the filing of six patents."

This product contains locally sourced additives, with the capability to adapt mixes to regional availability. The ACT cement is expected to reduce water usage by one-third compared to conventional concrete. An ACT-based concrete reportedly emits 198kg CO₂/t, a substantial reduction from the 614kg CO₂/t for standard concrete in France.

Gaining market entry for ACT required European technical evaluation and European assessment document certification, currently pending in the EU Official Journal. Trassard added, "As we are dealing with clinker rates below the standards, we had to go through this certification, which gives us a very good passport for the European markets. However, local administrative variations will have to be carried out subsequently."

In France, Ecocem has already applied for ATEX certification to facilitate deployment of the ACT range, expected later in 2024. Ecocem aims to include the ACT range in standard norms by 2026.

Germany: Heidelberg Materials reported sales growth of 0.4% in 2023, to €21.2bn. The group saw its profits grow by 21%, from €1.72bn to €2.09bn. During the year, the company reduced its specific CO₂ emissions per tonne of cementitious material by 3% from 551kg to 534kg and lowered its clinker factor from 72% to 70%.

Chair Dominik von Achten said "In the 150th year of our company's history, we have once again shown that we can deal with change and crises. I am extremely proud of our teams around the world, who have remained firmly focused on our targets and have once again done an extraordinary job." He added "We are entering 2024 with optimism. Although the general economic conditions in the construction sector remain challenging, we anticipate growth in revenue and earnings also in the current year. Our shareholders are benefitting from this growth thanks to the progressive dividend and the new, comprehensive share buyback programme.”

Egypt: Lafarge Egypt has confirmed that it is aiming to reduce its CO₂ emissions in excess of 20% by 2030. Its key steps to achieve this include increasing its use of alternative fuels and lowering its clinker factor, according to the Daily News Egypt newspaper. Chief executive officer Jimmy Khan added that the company is also working on developing digital methods to reduce emissions by improving transport logistics. The cement producer launched its Shatbna Masonry Cement product in 2022, part of parent company Holcim’s ECOPlanet range.

Holcim has set a worldwide target to reduce its gross Scope 1 CO₂ emissions from cement production of 22% by 2030 from a baseline of 590kg/t in 2018. It reported a 5% reduction to 562kg/t in its 2022 sustainability report. Ultimately the group is targeting net zero emissions from its activities by 2050.

Europe: 12 decarbonisation-focused companies from across the European cement and concrete sector have launched the Alliance for Low-Carbon Cement & Concrete (ALCCC). The alliance has called on policymakers to change building standards to help low-carbon alternatives to enter the cement and concrete markets. It further said that green procurement and targeted financing instruments would help to reduce sectoral CO₂ emissions. It said that a progressive decline in clinker factor to 60%, 50% or 40% by 2050 will reduce CO₂ emissions by over 50%. The ALCCC says that it is ready to lead the sector towards a swift, low-cost and viable decarbonisation pathway. Participants in the alliance include France-based Hoffmann Green Cement Technologies, Ireland-based Ecocem and US-based Fortera.

Fortera's Europe director Thierry Legrand said "Climate action is a global priority, and collaboration is essential to advancing emissions-reducing technologies and policies. This alliance represents collective action by scientists, engineers, entrepreneurs and environmental advocates to reduce CO₂ emissions from cement production."

France: The French cement association France Ciment has announced a new CO₂ emissions reduction target of 50% across the cement industry between 2021 and 2030. The new target for 2050 will be 'virtual carbon neutrality.' The Les Echos newspaper has reported that the commitments replace previous reduction targets of 24% by 2030 and 80% by 2050. France Ciment says that its members are planning estimated investments of Euro5bn towards achieving the goals before 2040. These investments will cover areas including the deployment of carbon capture. Existing public and private investments in the industry's on-going projects to reduce CO₂ emissions amount to Euro1.7bn - sufficient to eliminate 27% of emissions compared with the 2021 baseline.

France Ciment’s President Benoit Pillon noted the necessity of cement in construction, and called for 'decarbonisation as a whole: less clinker in cement, less cement in concrete and less concrete in construction.' He urged the implementation of policies to secure 'decarbonised and competitive electricity.'