Displaying items by tag: supplementary cementitious materials

US: Queens Carbon has secured a US$14.5m grant from the US Department of Energy under its SCALEUP program. The funding will support the pilot of Queens Carbon's low temperature, ‘zero CO₂’ emission technology at an existing cement production site. Queens Carbon's supplementary cementitious materials, which replace 20-50% of the high-CO₂ binder in cement, will be produced at a pilot plant with a capacity of 10t/day.

CEO Daniel Kopp said “This SCALEUP grant is a tremendous step forward on our path to commercialisation. Partnering with the Department of Energy and a major cement industry player to deploy, operate, and optimise our 10t/day pilot plant will put us on an accelerated path to gigatonne-scale CO₂ reductions.”

The National Development and Reform Commission and other government bodies in China released plans this week to cap clinker production capacity at 1.8Bnt/yr by the end of 2025. Energy efficiency of existing capacity will be used as the driver to determine which production lines can remain open. 30% of capacity will be required to be above the benchmark energy efficiency level. Plants below this line will be obliged to upgrade or face elimination.

Points of interest from the longer release include detail on how the authorities intend to promote energy efficiency. Installing improved production line equipment is as might be expected. However, there is also a drive towards low-carbon fuel substitution such as an increased thermal substitution rate (TSR) through the use of alternative fuels (AF), promotion of renewable energy sources and, interestingly, no new cement plants will be able to add captive coal power plants. The government is targeting a TSR of 10% by the end of 2025 with 30% of lines using AF in some form or another. A plan to reduce the clinker factor in cement is also being pushed through for the increased use of blast furnace slag, fly ash, carbide slag, manganese slag and other supplementary cementitious materials. This last point might have big implications for the ferrous slag export market but that’s a story for another day.

Working out how much these new measures will affect the cement sector in China in the short term is not straightforward since it’s unclear what the country’s actual production capacity is and how much of it is actually active. Data from the National Bureau of Statistics of China showed that cement output was 2.02Bnt in 2023. The China Cement Association (CCA) estimated that the capacity utilisation rate was 59% in 2023. So, if the sector were using all of its integrated cement plants flat out, then one might crudely suppose that the national production capacity might be around 3.5Bnt/yr. This guess does not take into account the prevalence of blended cements and a whole host of other factors so should be treated with caution. Given that cement output fell by 5% year-on-year in 2023, output could be just over 1.8Bnt in 2025 if the rate of decline holds. Research by Reuters in April 2024, suggested that the capacity utilisation rate hit 50% in that month, suggesting that the sector could meet the target in 2024 if it’s a particularly bad year. So, provided the production cap is enacted along the same lines of peak-shifting, where plants are temporarily shut for periods, then the target looks well within reach.

As reported in April 2024, the Chinese cement sector has faced rationalisation in recent years as the real estate market collapsed. Output peaked in 2020 and then fell subsequently. Most of the big producers endured falling sales volumes, revenue and profit in 2022, although some managed to resist the continuing decline in 2023. One coping mechanism has been to focus on overseas markets as proposed by the government’s Belt and Road initiative. Huaxin Cement has been a particular proponent of this strategy. The CCA says that China-based companies have invested in and built 43 clinker production lines in 21 countries with a cement production capacity of 81Mt/yr. Another 43Mt/yr of capacity is currently being built outside of China with yet another 25Mt/yr of capacity proposed for construction.

It is interesting, then, to note that the CCA issued an official warning this week to its members to invest ‘cautiously’ in Uzbekistan. The association said in a statement that at the end of April 2024 the country had 46 integrated production lines with a cement production capacity of 38Mt/yr. This is double the country’s demand for cement. Half of this production capacity is managed by China-based companies. It added that the utilisation rate was currently 50%, that the price had dropped by about 40% since 2020 and that competition was ‘fierce.’ Incredibly, another 7Mt/yr of capacity is expected to be added in 2024. The CCA has advised Chinese companies to consider the state of the Uzbek cement market before making any more investments.

The two news stories we have explored this week cover two sides of the same issue: Chinese cement overcapacity. The local market is finally slowing down after a period of phenomenal growth and the big question is what is the actual market demand now that all the big stuff has already been built. The government gives every impression it is using the decline to meet its sustainability goals. Like institutions in many other places it has set itself targets that it seems likely to meet. The flipside of overcapacity at home is investment overseas. China-based plant equipment manufacturers have certainly done well out of this situation. Yet in Uzbekistan, at least, it looks like the cement sector in China has also managed to export its overcapacity. This has created the absurd situation where the CCA has implored its members and others to exercise the same self-discipline abroad that the government extols at home. Another way to put this might be that Chinese cement companies are increasingly unable to make money at home… or in Uzbekistan. This then leaves a query over where else enthusiastic Chinese cement investors may be causing market imbalances. One solution might be for the Chinese government to impose a cap on clinker production by its companies outside the mainland. Whatever happens next though, the introduction of a capacity cap in mainland China marks a decisive change to the local cement sector.

Germany: France-based Fives has won a contract to build a 50t/day clay calcination unit at Rohrdorfer’s Rohrdorf cement plant in Bavaria. The unit will integrate into the plant’s clinker line in order to allow it to test the production of limestone calcined clay cement with up to 40% reduced CO₂ emissions. Fives’ clay calcination unit uses a flash calcination process, based on a three-stage preheater, flash calciner and decolourisation system.

Rohrdorfer’s Net Zero Emissions Labs team is responsible for the project to decarbonise the Rohrdorf cement plant by 2038. Its managing director Helmut Leibinger said “After a detailed technical review, we decided that the flash calciner with an integrated clay calcination unit from Fives FCB was the best solution in terms of reliability, efficiency and colour control. We are confident that the unit will be essential in moving forward on our pathway to net zero.”

The Indonesian government emphasised its intention this week to use ‘green’ cement in the construction of its new capital city Nusantara in Borneo. However, this begs the question: what exactly is ‘green’ cement?

In this case, Mohammad Zainal Fatah, the secretary general of the Ministry of Public Works and Public Housing, told state media that his department was “seeking to encourage the supply of domestic-industry-based material resources and construction equipment, which can support sustainable infrastructure development principles." The ministry is working with state-owned cement producers such as Semen Indonesia (SIG) to ensure the provision of sustainable cement and related products. SIG was selected as a supplier for the project in late 2022 and, as of February 2024, has reportedly provided 400,000t of cement from its plants at Balikpapan and Samarinda.

This is admirable stuff. However, the timing of the announcement is curious given that both the head and deputy head of the Nusantara Capital City Authority resigned this week forcing the government to reassure investors that the project was still on. Cue some swift discussion about ‘green’ cement! Previously it was hoped that the first phase of the US$34bn project could be inaugurated on the country’s independence day in August 2024 with civil servants scheduled to start relocating to the site in the autumn.

SIG sells a number of ‘green’ blended cement products and some of these have received Green Label Cement certification from the Green Product Council Indonesia. The group says that these products have contributed up to a 38% drop in CO₂ emissions compared to Ordinary Portland Cement (OPC). This compares to the group’s clinker factor reduction rate of 69% and its Scope 1 emissions intensity reduction of 17% to 585kg/CO₂/t of cement in 2023 compared to 2010 levels.

Along similar lines, the Alliance for Low-Carbon Cement & Concrete (ALCCC) in Belgium also announced this week that it had released a new policy roadmap aimed at achieving net zero emissions by 2040. Amongst its recommendations were a focus on the standards for cement and concrete to promote low-carbon products and encouragement to create lead markets to develop demand for them.

Crucially, the ALCCC uses low-carbon cement in place of ‘green’ cement and this makes its definition clearer. ‘Green’ cement is a marketing term intended to associate cement with environmentalism. Yet there is no accepted definition describing how these products are more sustainable than, say, OPC. For example, a so-called ‘green’ cement could use 100% clinker manufactured with no CO₂ emissions-abatement, but it might be sustainable in other ways such as saving water. For the purposes of this article we’ll assume that ‘green’ cement means a low-carbon one. To further add to the confusion, ‘green’ concrete can be made using OPC in various ways but that’s beyond the scope of this piece. Clearly the world could do with some universal definitions.

US-based research and consulting company Global Efficiency Intelligence came to the same conclusion when it published its ‘What are Green Cement and Concrete?’ report in December 2023. It decided that - despite there being plenty of standards, protocols, and initiatives - there is no general agreement on the definition of ‘green’ cement or concrete. Its emissions intensity for cement summary table can be viewed below. It demonstrates the massive range of emissions intensity between the various standards. It is worth noting here that the description the Indonesian government may have been using for ‘green’ cement could already meet SIG’s Scope 1 emissions intensity reduction for its cement in 2023 depending on the standard being used.

Table 1: Emissions intensity definition for cement as stated by standards, protocols, initiatives, and policies with stated numerical quantity targets. Source: Global Efficiency Intelligence.

Part of the problem here is that there is a language gap between the simple definition of a cement that is less CO₂ emissions-intensive than OPC and the technical definitions used in the specifications and standards. Simply describing a cement product as ‘green’ can potentially cover anything that is slightly better than OPC down to a bona-fide net-zero product. Added to this is pressure from the manufacturers of new and existing cement products that use less or no OPC for regulators to move to performance-based standards to replace existing prescriptive standards, because it makes it easier for their products to be used. For more on this issue see Global Cement Weekly #606. Cement associations such as Cembureau and the Global Cement and Concrete Association (GCCA) have also called in their respective net zero roadmaps for changes to the standards system to promote low-carbon cement and concrete products.

The answer to what is ‘green’ cement is whatever the promoters want it to be. So, it might be helpful if the use of the word ‘green’ were banned in connection to any marketing activity related to cement products. Everyone could then adopt some kind of universal grading system using simpler language. One approach might be to copy the colour-coding scheme used by hydrogen to describe how it is made. One could use yellow for limestone blends, silver for slag, orange for clay, black for OPC made with carbon capture and so on… but not green! Another route might be to mandate the use of the carbon labels that some cement producers have used for at least a decade. Or something like the alphabet energy rating system used in the UK and EU for electrical appliances could be used. It’s too much to hope for a global system but simpler systems in the main markets would make it much easier to determine what exactly is ‘green’ cement.

Peter Edwards, Editor of Global Cement Magazine, discusses ‘sustainable’ cement in The Last Word in the June 2023 issue

US: St Marys Cement won three national awards at the Slag Cement in Sustainable Concrete Awards 2023. The producer won the awards for supplying its slag cement for the construction of Wixom Assembly Park in Wixom, Michigan; of 333 North Water in Milwaukee, Wisconsin, and of Excellerate Manufacturing in Appleton, Wisconsin.

Netherlands: EMC Cement and HES International plan to build a 1.2Mt/yr plant in Amsterdam to produce an alternative cement that contains 70% volcanic ash. The cement will also include recycled concrete fines. Production will be carbon neutral and consume 90% less energy than traditional ordinary Portland cement production. The Amsterdam plant is scheduled for commissioning by early 2026.

EMC Cement CEO Atle Lygren said "Our EMC Technology, by replacing 70% of Portland cement clinker, enables significant climate action without the need for costly carbon capture and storage, aligning with the demands of the United Nations Framework Convention on Climate Change and the Intergovernmental Panel on Climate Change."

France: NeoCem plans to build a €50m clay calcination plant at Saint-Maximin, Picardy. The company recently raised €23m in investments in its Series A funding round. The Le Journal des Enterprises newspaper has reported that the Saint-Maximin plant will enter operation in 2025, and will subsequently grow to 200,000t/yr in capacity. NeoCem aims to employ 100 people by 2030.

Head of industrial deployment Guillaume Luu said “To be used in concrete, limestone must be heated for several hours at 1400°C. Our clay-based binder generates CO₂ emissions of 120kg/t, compared to almost 1000kg/t of limestone binder, and our technology can transform all types of clays available. The idea is not to open new quarries, but to give a second life to materials already on the surface." He continued “The up-cycling of clays and their transformation into a low-carbon binder addresses several challenges for the construction sector. On the one hand, the reuse of clay waste, and on the other hand, the decarbonisation of the building materials sector.”

Ireland/France: Ecocem will showcase its Advanced Cement Technology (ACT) at the Buildings and Climate Global Forum in Paris on 7-8 March 2024. The French Government and United Nations Environment Programme (UNEP) will host the event, supported by the Global Alliance for Buildings and Construction (Global ABC). It aims to advance the climate outcomes of the United Nations Climate Change Conference (COP28) in 2023. Ecocem joins global policy-makers, industry stakeholders and international organisations as the event’s sole international cement technology company exhibitor.

Managing director Donal O'Riain said "The Buildings and Climate Global Forum is happening at a crucial moment for the planet. Urgent and deep decarbonisation of construction materials is essential to achieving the 2015 Paris Agreement targets.” He continued “Ecocem’s ACT low carbon technology can decarbonise the cement sector on a trajectory consistent with 1.5°C of global warming, the first major industry sector to achieve this feat. But we must now mobilise resolutely, rapidly and globally to deploy this technology. The first ambition should be a 50% reduction in CO₂ emissions from cement by 2030. Technology is no longer the barrier."

UAE: Emirates Steel Arkan has concluded a partnership for the deployment of Finland-based Magsort’s technology in steel slag processing at its Al Ain cement plant. ZAWYA News has reported that the partners expect the technology to help reduce the plant’s limestone and fuel consumption. This will reduce its CO₂ emissions by 15%.

Emirates Steel Arkan CEO Saeed Ghumran Al Remeithi said "Green solutions such as this will help decarbonise the sector's value chain."

US: The Department of Transportation has announced a US$5m initiative to investigate the use of steel slag in cement and concrete. This will take the form of a collaboration between the Department of Transportation and a selected US-based steel producer and university partner. The initiative seeks to reduce CO₂ emissions in the production of building materials. Prospective participants may view the grant opportunity here.

Transport secretary Pete Buttigieg said "We're proud to make this funding available to help develop the next generation of construction materials so that the future of our transport infrastructure is more resilient, more sustainable and made in America.”

Robert Hampshire, deputy assistant secretary for research and technology and chief science officer, said “This funding initiative will develop and advance innovative materials and technologies that support the nation’s goals to decarbonise the transportation sector by 2050, strengthen resilience of the nation’s transportation infrastructure, and address adverse environmental impacts created by the transportation system.”