Displaying items by tag: Calcined Clay

Denmark: Aalborg Portland Cement says that the market ‘warmly welcomed’ its new FUTURECEM calcined clay cement in 2021. The product has reached its sales expectations for the year and is now nearly sold out for 2022. The company says that its plan to ramp up FUTURECEM production to replace 50% of grey cement production at its Rørdal cement plant is on track.

Parent company Cementir Holding says that the success of FUTURECEM rests on four pillars, namely its suitability for intended applications, targeted communication, close dialogue with concrete producers and the entire value chain and strategic partnerships with leading construction clients. It said “The lesson learned is that the market needs thorough information about new products and its industrialisation to rely on and implement them in place of conventional products.” The group added that its experience in Denmark paves the way for limestone calcined clay technology rollouts in other markets in line with its sustainable roadmap towards 2030.

India: ACC and Ambuja Cements have partnered with the Indian Institute of Technology Delhi (IITD) to develop a range of calcined clay cements with 50% lower CO₂ emissions than Ordinary Portland Cement (OPC). The collaboration will vary clinker, calcined clay and limestone levels in calcined clay cements in order to ascertain their effects on its performance. France-based Holcim Innovation Centre will fund the research.

Holcim India chief executive officer and managing director Neeraj Akhoury said "Through our extensive research and development setup, we consistently strive to develop new low-CO₂ materials for the construction industry. Calcined clay cement is one such avenue to make a significant quantitative difference in the industry and further accelerate our sustainability drive. Our academic partnership with IITD is a big step towards building a greener future and we are excited to collaborate with the best minds in the country."

The producers have previously partnered with the Indian Institute of Technology Madras (IITM) to study low-CO₂ binders with alternative reinforcements and with the Indian Institute of Technology Hyderabad (IITH) to develop smart sensing technology for continuous on-site strength evaluation of a concrete structure.

Holcim has started to unify its low carbon cement product range this week with the launch of its ECOPlanet label globally. The products are already available in Germany, Romania, Canada, Switzerland, Spain, France and Italy. The plan is to extend this to 15 countries by the end of 2021 and then to double its ‘market presence’ by the end of 2022.

The headline news is that the range will include what Holcim says is the world’s first cement product with 20% recycled construction and demolition waste. This appears to be an improvement on the group’s Susteno cement products that use fine fractions from concrete and demolition waste. This product is currently sold in Switzerland where it is advertised as saving 10% of CO₂ emissions compared to a standard cement product. Both Holcim and HeidelbergCement already sell concrete products that use the coarse waste from building demolition. Other than this, Holcim says that the range will also include cements that contain calcined clay. In June 2021 subsidiary Lafarge France announced that it would produce a cement product under the ECOPlanet banner using kaolin clay with its proprietary ProximA Tech process at its integrated La Malle cement plant in Bouc-Bel-Air.

We will have to wait and see how far Holcim goes in standardisng the range between different countries. Yet, judging from what the countries that are already selling ECOPlanet are doing, it looks like it will be a variety of blended cements. At present, for example, Holcim Germany offers four products in the ECOPlanet range. These are all slag cements, with three having effective CO₂ reductions of up to 70% and the fourth, ECOPlanet Zero, reaching 100% through a carbon offsetting scheme in conjunction with MoorFutures. Holcim Italy also launched a product in the range called ECOPlanet Prime using calcined clay in June 2021.

Incidentally, LafargeHolcim US announced a research project this week with the US Army about using demolition waste. It’s going to start working with the US Army Corps of Engineers’ Engineer Research and Development Center and Geocycle to look at how construction and demolition materials from military installations can be used for energy recovery and mineral recycling. Group resources at Geocycle’s Holly Hill Research Center in South Carolina, US and Holcim’s Global Innovation Center in Lyon, France will be used in the scheme.

Other low carbon cement products are available of course. Holcim is far from alone in launching low CO₂ cement and concrete products. Yet the use of worldwide brand names is different. Cemex is doing something similar with the global rollout of its Vertua concrete products. It first launched Vertua in France in 2018 before going global in 2020. Holcim started to launch ECOPact Concrete in 2019. Now, Holcim has gone further by doing the same thing with cement. Given how localised cement and concrete products are, it will be instructive to see how global branding for low carbon cementitious products helps these companies. For instance, who is the target audience? It could be eco-minded self-build customers or project specifiers or government departments or industry lobbyists. Or perhaps it is simply another marketing channel to reinforce the sector’s sustainable offerings.

The other point worth considering is when will the multinational cement producers start selling sustainable cements and concretes in less rich parts of the world? While Holcim was playing with blended cements and marketing this week, Dangote Cement said that it was ready to start commissioning its new 6Mt/yr integrated plant at Okpella, Edo State in Nigeria. Another 5Mt/yr plant is also on the way in the country from Madugu Cement. It has just signed a contract for China-based Sinoma International Engineering Company to build it. When Holcim and the other cement companies start selling low carbon cements in places like Nigeria then the rise of these products will be complete.

For more information on low CO₂ cement production read our feature in the February 2021 issue of Global Cement Magazine

Australia: Calix has joined as a partner of the Heavy Industry Low-carbon Transition Cooperative Research Centre (HILT CRC). The initiative brings together heavy industry players, government and research and aims to boost the capability of Australian companies to remain globally competitive by capitalising on existing mineral and renewable energy resources to become international producers and exporters of low-carbon products. HILT CRC has secured US$29m from the government. This joins funding of US$158m in direct and in-kind contributions from its partners over the last decade.

“It is a chance for us to demonstrate the technology developed for CO₂ mitigation in the production of cement and lime through our European LEILAC-1 and 2 projects in an Australian setting, as well as explore other more sustainable applications for our technology in heavy industry, backed by this impressive team of researchers and industrial participants," said Calix’s managing director Phil Hodgson.

As part of the HILT CRC, Calix will continue to develop its technology for the reduction of carbon emissions from lime and cement production, and also use its Calix Flash Calciner (CFC) technology to develop other more processing applications such as for bauxite processing for the aluminium industry and production of calcined clay from kaolinite for use in new lower carbon cements.

HILT CRC’s core industrial partners include Adbri, Alcoa, Boral, Fortescue, Grange Resources, Liberty, Roy Hill and South32. The initiative has its headquarters in Adelaide and it plans to establish hubs in heavy industry regions of Gladstone, the Pilbara, Northern Tasmania, South Australia’s Upper Spencer Gulf, Western Australia's Kwinana and South West regions, the Southern Highlands of Nnew South Wales and Portland in Victoria.

France: Denmark-based FLSmidth has won a contract to supply a 400t/day calcined clay production line to Vicat’s Xeuilley integrated cement plant. The order includes flash calciner technology, an environmental control system and alternative fuel (AF) firing, handling and storage equipment. The line will have a design capacity of up to 525t/day and is scheduled for commissioning in 2023. It will enable clinker substitution in cement of up to 40%, according to the supplier. It says that cement produced using calcined clay will have a 16% smaller carbon footprint than its clinker-based equivalent. The value of the contract is Euro26.8m.

Vicat deputy chief executive officer Eric Bourdon said, “EU regulations and increasing demand for more sustainable cement has accelerated the decision to introduce clay as an environmental alternative to clinker in our production. With clay readily available in the area and positive results from pilots at FLSmidth’s test facilities in Denmark, we feel confident about the technology and hope to be able to expand further in the future.”

Cameroon: Aumund France has won a contract to supply three BWZ type bucket elevators with central chain, three BWG type belt bucket elevators and three Samson material feeders to Oyak Çimento’s upcoming plant near Kribi. When commissioned in September 2022, the plant will grind 100t/day of cement and 720t/day of calcined clay. ThyssenKrupp Industrial Solutions (France) is responsible for the overall design, supply and installation of equipment to the plant.

Italy: Caltagirone Group subsidiary Cementir Holding has announced the upcoming launch of its FutureCem grey cement product on 1 January 2021. The company says that it has 30% lower CO₂ emissions than normal ordinary Portland cement (OPC). It developed the product in collaboration with its Denmark-based subsidiary Aalborg Portland using 35% limestone and calcined clay to replace clinker. This resulted in a much more sustainable, high grade cement according to the company. It added that the low carbon benefits of FutureCem have been achieved without compromising strength and quality.

Chief sales, marketing and commercial development officer Michele Di Marino said that FutureCem is a ‘giant step’ on the way towards more sustainable cement production. “This is immensely important if we are to achieve our sustainability goals at Cementir Group,” said Di Marino. “But it is also an important contribution to the green transition of the concrete and construction industries in general. Thanks to the efforts of our research and development department in Aalborg, we are ready to begin distributing the FutureCem technology in Denmark and soon other subsidiaries in Europe will follow.” He added, “We have reached an important milestone in our innovation and sustainability efforts, but we are not done. Currently, we are incorporating the technology into more cement types in our product range. This includes white cement, and we have already introduced two white ultra-high performance concrete (UHPC) premix types with FutureCem technology.”

Cuba: The production of ‘low-carbon’ (LC3) cement consisting of clinker, calcined clay, limestone and gypsum has begun at Marta Abreu University’s 1460t/yr pilot integrated cement plant in Las Villas. The Granma newspaper has reported that the plant is currently producing 4t/day of cement, and plans to double this to 8t/day when fully operational.

Cement and concrete products with sustainability credentials have increased in recent years as societies start to demand decarbonisation. In spite of the recent drop in the European Union (EU) Emissions Trading Scheme (ETS) price, there has been a trend in recent years in the construction industry towards offerings with better environmental credentials. Indeed, this week’s position paper from Cembureau on a carbon border mechanism concerns directly the growth of these kinds of products within Europe. Typically, the higher profile projects have been slag cement or concrete implementations such as Hanson’s use of its Regen cement substitute in a London sewer project or David Ball Group’s Cemfree concrete in a road project also in the UK. In this short review we’ll take a selective look at a few of the so-called low carbon cement and concrete products currently available.

Table 1: Some examples of methods to reduce embodied CO₂ in cement and concrete. Note - the product examples are selective. In some cases many other products are available.

Looking at cement first, the easiest way for many producers to bring a lower carbon product to market has been to promote cements made using secondary cementitious materials (SCM) such as granulated blast furnace slag or fly ash. These types of cements have a long history, typically in specialist applications and/or in relation to ease of supply. For example, cement producers in eastern India often manufacture slag cements owing to the number of local steel plants. However, cement producers have more recently started to publicise their environmental credentials as they reduce the clinker factor of the final product. Alongside this though, in Europe especially, a number of so-called low carbon cement producers have appeared on the scene such as EcoCem and Hoffman Green Technologies. These newer producers tend to offer SCM cement products or other low carbon ones built around a grinding model. It is likely that their businesses have benefitted from tightening EU environmental legislation. How far cement producers can pivot to SCM cement products is contentious given that slag and fly ash are finite byproducts of other industries that are also under pressure to decarbonise. Although it should be noted that other SCMs such as pozzolans exist.

As will be seen below a few of the methods to reduce embodied CO₂ in cement and concrete can be used in both materials. SCMs are no exception and hold a long history in concrete usage. As mentioned above David Ball Group sells Cemfree a concrete product that contains no cement. Harsco Environmental, a minerals management company, invested US$3m into Carbicrete, a technology start-up working on a cement-free concrete, in late 2019.

Limestone calcined clay cements are the next set of products that are starting to make an appearance through the work of the Swiss-government backed LC3 project, more commercial offerings like FutureCem from Cementir and H-EVA from Hoffman Green Technologies and today’s announcement about ThyssenKrupp’s plans to fit the Kribi cement plant in Cameroon with its Polysius activated clay system. They too, like SCM cements, reduce the clinker factor of the cement. The downside is that, as in the name, the clay element needs to be calcined requiring capital investment, although LC3 make a strong case in their literature about how fast these costs can be recouped in a variety of scenarios.

Calcium silicate cements offer reduced process emissions by decreasing the lime content of the clinker lowering the amount of CO₂ released and bringing down the temperature required in the kiln to make the clinker. Solidia offers its calcium silicate cement as part of a two-part system with a CO₂ cured concrete. In the US LafargeHolcim used Solidia’s product in a commercial project in mid-2019 at a New Jersey paver and block plant. Solidia’s second core technology is using CO₂ to cure concrete and reducing water usage. They are not alone here as Canada’s CarbonCure Technologies uses CO₂ in a similar way with their technology. In their case they focus more on CO₂ mineralisation. In Germany, Schwenk Zement backed the Celitement project, which developed a hydraulic calcium hydro silicate based product that does not use CO₂ curing. Celitement has since become part of Schwenk Zement.

Solidia isn’t the only company looking at two complementary technologies along the cement-concrete production chain. A number of companies are looking at recycling concrete and demolition waste. Generally this splits into coarse waste that is used as an aggregate substitute in concrete and fine waste that is used to make cement. LafargeHolcim has Evopact for the coarse waste and Susteno for the fine. HeidelbergCement has EcoCrete for the coarse and is researching the use of fines. Closing the loop for heavy building material producers definitely seems like the way to go at the moment and this view is reinforced by the involvement of the two largest multinational producers.

Of the rest of the other low carbon cement methods detailed in table 1 these cover other non-Ordinary Portland Cement (OPC) such as geopolymer and calcium sulphoaluminate cements. The former are a type of alkali activated binder and generally lack common standards. The latter are similar to slag cements in that they are established specialist products with lower CO₂ emissions than OPC.

With concrete when trying to make a low carbon product the first choice is whether to choose a low-carbon cement as the binder or even not to use cement at all in the case of Regen or Cemfree. From here the next step is to simply use less cement in a concrete mixture. There are a number of ways to do this from optimising aggregate gradation, following performance specifications more closely, using strength tests like maturity methods and generally adhering to quality control protocols better to deliver more consistency. Read the Mineral Production Association (MPA) publication Specifying Sustainable Concrete for more detail on this. Using concrete admixtures can also help make concrete more sustainable by improving quality and performance at construction sites through the use of plasticisers and accelerators, by decreasing embodied carbon through the use of water reducers and by improving the whole life performance of concretes. The use of locally-sourced aggregates is also worth noting here since it can reduce associated transport CO₂ emissions.

More novel methods of reducing embodied CO₂ emissions in concrete include the use of geopolymer concrete in the case of Zeobond Group’s E-Crete or adding graphene as Concrene does. Like geopolymer cements, geopolymer concretes are relatively new and lack common standards. Products like Concrene, meanwhile, remain currently at the startup level. Finally, if all else fails, offsetting the CO₂ released by a cement or concrete product is always an option. This is what Cemex has done with its Vertua Ultra Zero product. The first 70% reduction in embodied CO₂ is gained through the use of geopolymer cement. Then the remaining 30% reduction is achieved through a carbon offsetting scheme via a carbon neutral certification verified by the Carbon Trust.

As can be seen, a variety of methods exist for cement and concrete producers to reduce the embodied CO₂ of their products and call them ‘low-carbon.’ For the moment most remain in the ‘novelty section’ but as legislators promote and specifiers look for sustainable construction they continue to become more mainstream. What has been interesting to note from this short study is that some companies are looking at multiple solutions along the production and supply chain whilst others are concentrating on single ones. The companies looking at multiple methods range from the biggest building material producers like LafargeHolcim and HeidelbergCement to smaller newer ones like Solidia and Hoffman Green Technologies. Also of note is that many of these products have existed already in various forms for a long time like SCM cements and concretes or the many ways concretes can be made more sustainable through much simpler ways such as changing aggregate sourcing or working more efficiently. In many cases once markets receive sufficient stimulus it seems likely that low carbon cement and concrete products will proliferate.

Global Cement is researching a market report on low carbon cement and concrete. If readers have any comments to make please contact us at This email address is being protected from spambots. You need JavaScript enabled to view it.

Cameroon: Germany-based Thyssenkrupp Industrial Solutions has won an engineering, procurement, construction and commissioning (EPCC) contract with Netherlands-based Cimpor Global Holdings for the installation of a clay calcination plant at its new integrated Kribi cement plant in the Port of Kribi in South Cameroon. The system calcines clay at just 800°C, which can then replace clinker at a ratio of one to two, lowering the finished cement’s clinker factor by up to 33%.

ThyssenKrupp says that use of the system, the first of its kind in Cameroon and second at a Cimpor Global Holdings cement plant, will help cut CO₂ emissions by 120,000t/yr, corresponding to a reduction of 40%.