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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. In Germany Schwenk Zement backed the Celitement project along similar lines. 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.

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.

Philippines: Holcim Philippines has recorded a profit of US$70.9m in 2019, up by 41% from US$50.3m in 2018. This was in spite of a 5.9% year-on-year sales fall to US$660m from US$701m in 2018. The Philippines Star newspaper has reported that a more favourable product mix and the steady contribution of its aggregates unit helped Holcim Philippines to offset the effects of slowing construction activity throughout the year. Holcim Philippines president and CEO John Stull said that the company is ‘well-positioned to deliver sustainable and healthy growth to shareholders and continue support to the country’s development.’

In 2019 Holcim Philippines brought its total production capacity to 10Mt/yr with the completion of upgrades at its integrated Bulacan, Davao and La Union plants. In March 2019 it launched Solido, a blended cement suited to use in road and infrastructure construction.

Australia: The Australian Competition and Consumer Commission (ACCC) says that Barro Group’s acquisition of a 43% stake in Adelaide Brighton will not ‘substantially’ lessen competition. The ACCC examined the completed acquisition closely because the two vertically integrated companies have overlap in the market for the supply of cement, ready-mixed concrete and aggregates.

It found Barro and Adelaide Brighton will continue to face competition from Boral, Holcim and Hanson, three large vertically integrated competitors with national operations, along with a number of smaller independent competitors. The ACCC looked at competition impacts on the pre-mixed concrete and aggregates markets in Melbourne, Brisbane and Townsville, where Barro and Adelaide Brighton’s operations overlap and did not identify any areas of concern.

Barro did not seek informal merger clearance from the ACCC prior to acquiring Adelaide Brighton. However, the ACCC says it may reopen its investigation if it receives further information that alters its current conclusions.

UK: Hanson has appointed Andrew Simpson as its packed products director, adding operational responsibility to his commercial remit. He is responsible for sales of all of its packed products, including cement, ready-to-use concrete and aggregates, and will now also look after manufacturing at the company’s ready-to-use production site in Nuneaton, as well as its construction aggregates packing plants across the country.

Simpson started his career with Hanson in 1997 when he was appointed area sales manager for Castle Cement, part of the HeidelbergCement Group, which bought Hanson in 2007. Since then he has held a number of different sales roles and attained a degree in Business Studies from De Montfort University in Leicester. In 2017 he was honoured with the freedom of the City of London and installed as a Liveryman of The Worshipful Company of Builders Merchants in recognition of his work within the builders’ merchants’ industry.

Thailand: Siam Cement Group’s concrete and aggregates division SCC Concrete Products and Aggregates (CPAC) has entered into a joint venture agreement with Swedish digitisation specialist BIMobject for the formation of BIMobject Thailand Co., Ltd. (BIMobject TH) on a 51:49 basis in favour of CPAC. This will provide building information modelling (BIM) - a service platform for use in conceptual design, material selection, and construction simulation of customers’ projects. Siam Cement Group president and CEO Roongrote Rangsiyopash said, “This is in line with SCC’s strategic plan to extend its breadth of innovative construction solutions.” The joint venture will have US$170,000 registered capital.

UK: Cemex has entered a conditional agreement with Breedon Group for the divestment of certain UK assets, including 49 ready-mix plants, 28 aggregate quarries and a cement terminal for Euro211m including Breedon Group’s assumption of Euro27.3m lease liability. Cemex UK retains the 1.2Mt/yr Rugby cement plant in Warwickshire. Breedon Group CEO Pat Ward said, “We expect the deal to be accretive to both earnings and free cash flow in the first full year, with a positive ongoing impact on the cash generation of the enlarged Group.” Cemex CEO Fernando Gonzalez said that the transaction ‘further rebalances our portfolio into our core markets, enhances our profitability and enables us to continue to focus on deleveraging.’

The businesses being handed over also include concrete products operations, depots and asphalt plants and fall under all six of Breedon Group’s regional divisions. Ward has said the acquisitions will significantly enlarge the group’s footprint in underrepresented divisions, implying that the cement terminal in question may be the Leith terminal in Scotland or the Newport terminal in Wales, two regions in which the company currently has no terminals to receive cement produced at its 1.5Mt/yr integrated Hope cement plant in Derbyshire. Breedon Group will seek to hire employees working on the operations from Cemex and expects to bring its total UK personnel to 3600 people as a result. It says its mineral reserves will exceed 1.0Bt.

Cemex UK retains 259 concrete plants and 36 aggregates quarries and dredging operations. Cemex said it ‘will retain a substantial integrated business in the UK encompassing cement production.’

UK: Hanson’s ship Arco Avon has uncovered a mammoth tooth whilst dredging the seabed for aggregates for use in cement production off the east coast of Norfolk. Natural History Museum palaeontologists have identified the specimen has having belonged to a 35-year-old animal that died between 10,000 and 0.35m years ago. The dredging lane, 10km offshore from Great Yarmouth, has previously turned out mammoth vertebrae and a tusk fragment.

Bulgaria: The Bulgarian government has terminated Devnya Cement’s concessionary contract for the extraction of quartz sand for cement production from the Selski Nivi deposit. SeeNews has reported that the company requested the contract’s termination due to alterations to its production strategy in response to market conditions.

In 2018, Devnya Cement generated a revenue of Euro70.3m, which translated into Euro8.65m profit.

Spain: The European Union of Aggregates Producers has granted two Sustainable Development Awards to Brazil’s Votorantim Cimentos for its El Toril quarry restoration plan and cave conservation plan for the Cova Eirós mine, which provided raw materials for clinker produciton at its 0.7Mt/yr integrated Oural plant. Votorantim Cimentos has partnered with the University of Santiago de Compostela to facilitate archaeological study of Cova Eirós, where 50,000-year-old findings have been made. Meanwhile at El Toril, the pit will be filled, levelled and enhanced for fertility so that it may resume its previous use as arable land.

Uzbekistan: Construction has begun at Russia’s Eurocement’s 2.0Mt/yr integrated Ankhangarancement plant in the Tashkent region of a facility to house the limestone and clay used in cement production. When the installation is operational, the materials will be relayed from it to the plant’s four wet lines by a conveyor belt and 1400t/hr stacker, whence the mixture is conveyed by 600t/hr-capacity truck to one of the vertical roller mills.