Displaying items by tag: Demolition

Germany: HeidelbergCement has joined EPEA’s Heidelberg Circular City Building Material Registry pilot project. The initiative uses EMEA’s Urban Mining Screening digital registry, which is able to estimate the composition of buildings based on building data. HeidelbergCement says that it will enable it to source construction and demolition waste for circular economic use in building materials production. This will support its ReConcrete 360° recycled concrete CO₂ reincorporation project, among other projects. The initiative will turn Heidelberg into Europe’s first Circular City.

“Full circular economy and sustainable construction are central elements of our climate strategy,” said HeidelbergCement chair Dominik von Achten. “We are focusing on the life cycle assessment of our product concrete, including the processing of demolished concrete, and returning it to the construction cycle. By 2030, we want to offer circular alternatives for half of our concrete products.” Von Achten concluded “Together with the city of Heidelberg, also a pioneer in the area of climate protection, we want to use the Circular City project to demonstrate the enormous potential of concrete recycling for future urban construction.” 


Canada/US: Holcim North America has invested in Blue Planet to support the development and commercialisation of its mineralisation technology. Blue Planet’s process sequesters CO₂ with building waste feedstock such as recycled concrete, cement kiln dust (CKD) and slag to produce new aggregate products. Each tonne of Blue Planet’s aggregate can mineralize up to 440kg of captured CO₂. Lafarge Canada, Holcim US, and Blue Planet will start a multi-year collaboration to help identify potential to use the mineralisation technology to further lower the carbon footprint of the companies’ cement, aggregates and concrete operations, with the potential to expand to other operations in the Holcim Group around the world.

“This is an important step for us in North America. Our vision is to transform our St Constant Plant in Montreal into a carbon campus that ultimately advances commercialisation of mineralisation technologies, including Blue Planet’s products,” said David Redfern, president and chief executive officer, Lafarge Canada. “We look forward to advancing our Net Zero strategy by leveraging mineralization technology that allows us to use the CO₂ from our own cement plants to produce carbon neutral or carbon negative sand and gravel products.”

Austria: The Austrian Cement Industry Association (VÖZ) has launched a roadmap for carbon neutrality by 2050. The initiative follows the 5C approach of Clinker, Cement, Concrete, Construction and Carbonation as prompted by the European Cement Association, Cembureau. Selected targets from the document include reducing the sector’s average clinker factor to 52% by 2040 from 70% in 2020, using carbon-neutral electricity from 2030 and meeting a recycling rate for concrete and demolition waste of 25% in 2050 from 10% in 2022. Sebastian Spaun, the managing director of VÖZ, highlighted the ‘Carbon2ProductAustria’ (C₂PAT) initiative as a key project where capture CO₂ from Lafarge Zementwerke’s Mannersdorf cement plant will be used with hydrogen to produce synthetic fuels, plastics or other chemicals.

Spain: HeidelbergCement is starting the Neuclicem carbon capture use and storage (CCUS) project at its integrated Arrigorriaga plant near Bilbao. Local electricity company Volbas and the Tecnalia Research & Innovation centre are participating in the initiative. The project intends to look at a process based on the mineralisation of alkaline waste, such as residual construction waste or steel slag, by accelerated carbonation using CO₂ from the flue gas at the plant. The resulting materials will then be used as additives in cement production or to reduce the use of clinker. The scheme will study its viability of the process on an industrial scale.

The Neuclicem project has an estimated duration of 14 months. Its results are intended to prepare the way for scaling up to a subsequent industrial prototype. The project is partially financed by Ihobe, an environmental management division of the regional Basque government.

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

Poland: Switzerland-based LafargeHolcim subsidiary Lafarge Polska has launched Aggneo, a recycled aggregate recycled from demolition-sourced concrete. The producer says that Aggneo offers high consistency and a lower density than mined aggregates, resulting in material savings. Besides reducing waste, the product also lowers the carbon footprint of delivery by 66%, according to the company. The building materials producer aims to manufacture 1Mt/yr of recycled aggregated by 2030.

Spain: Cementos Molins has dismantled kilns 3, 4 and 5 of the Sant Vicenç dels Horts cement plant in Catalonia. The company says that it will use 48,000t of waste material from the demolition process in cement production in kiln 6 at the plant. The material consists of 35,000t of concrete, 10,000t of scrap metal, 1450t of refractory material and 1500t of other waste.

The total investment cost of the dismantling work was Euro2m. The company said that the demolition of silos presented the most complex challenges of the 24-month process.

The plant mothballed lines 3, 4 and 5 upon the opening of line 6 in 2010.

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.

Here’s a fun idea: providing building materials as a service. Instead of the owner of a building possessing all the materials in it forever, they simply rent them. It would be like a music or television streaming service. A ‘Netflix’ or ‘Spotify’ for the construction industry. ‘Rentacrete’ if you will…

The Guardian Cities series has been discussing the idea this week in a feature on whether buildings should be demolished at the end of their lifetime. The feature largely looks at the ideas of Dutch architect and commentator Thomas Rau, the author of Material Matters. He talks about his ‘materials passport’ concept whereby all the materials in a building are logged with their properties to highlight their value when the structure is demolished. This is a refinement of the Building Information Modelling (BIM) system. Rau has put his passport premise into action for a couple of projects through his firm and the Madaster Foundation promotes its use.

The next steps that he envisages are buildings where the materials that constitute it are simply rented from the manufacturer. Since the material owners would now become companies they would have an interest in efficiency where the materials can be refitted, such as lighting, and/or recycled for when the building is torn down. In Rau’s view these companies would be in a better position to recoup the value of these materials when a building is demolished. He estimates that 18% of a building’s original construction cost can be preserved in this way. Suddenly, sustainability becomes much easier by changing one’s perspective on who owns what exactly in a building.

How this idea would work in practice raises all sorts of questions. For example, most buildings in the developed world last for as least as long as humans do. Which companies could be relied on to hang around this long? Building materials as a service might work for soft materials that are replaced more often, such as lighting and other interior fittings, but could this extend to a structure’s shell? One answer to this is that people invest in pension schemes and use banks quite happily over long periods time, so why not a building’s very fabric? Another issue is of liability and whether a manufacturer would want to take on additional responsibilities for its products decades later. This, and the idea in general, have similarities to the extended product responsibility strategy. Obviously someone needs to try out building materials as a service for real to tackle these questions and many more.

Building materials as a service is compelling but one reason that the construction industry has proved resistant to the digital revolution across the entire business, so far, is because it ultimately deals with physical products that people need permanently. Consumer digital renting services for media, like Netflix and Spotify, are ‘disposable’. Hence, the mindset is different. That’s not to say that building materials as a service is impossible just that it is a harder shift in thinking. A country with a high level of residential renting, for example, might find it easier to move to this model than one with high levels of home ownership.

One more thing to consider is that the media renting companies mentioned above are dependent on other companies producing the content. Due to this they have moved towards vertical integration as the producers themselves, notably Disney in 2019 which has started to set up its own online rental platform. The point here being that in a product rental environment, whoever produces the product, holds a large amount of influence. Building materials manufacturers take note. Building materials as a service might just be a talking point on the lecture circuit along the road towards sustainability in the construction industry. Yet if it did happen at any scale then the producers of concrete, mortar, bricks, steel and all the rest would be well placed to benefit from it.

China: Three cement plants in Dali, Yunnan province with a combined capacity of 5.0Mt/yr and belonging to Dali Cement (Group), Dali Hongshan Yunnan Cement and Hongta Dianxi Cement have ceased all functions except the packaging of existing cement in order to stop polluting the area of Erhai Lake. The shutdown was mandated by the City of Dali and Dali Economic Development Zone authorities in mid-2017. Xinhua Net newspaper has reported that the removal of kilns is underway and that demolition on all three sites will have been completed by 31 May 2020. The companies will be permitted to construct plants of corresponding capacities at allotted sites elsewhere.