New Innovation in Sustainability

New innovation in sustainability

International News: Calcined clay is an innovative product, developed over 14 years, which is now finally ready and available for the market. 

Not only will it replace cement, but also significantly reduce the CO2 footprint.

This summer Geir Norden - our own R&D specialist in calcined clay from Norway - will attend two conferences in Europe to discuss in detail the sustainable achievements created by LECA.

Interview with Geir Norden

M.Sc, NTNU Trondheim

Concrete technology, construction materials

30 years of experience from international R&D, product development and market implementation

How would you describe your work within Research and Development (R&D)?

Research & Development (R&D) is the ability to be a few steps ahead of what is happening. Its purpose is to try to understand and predict what will happen in the future. To achieve this, it is necessary to be informed about what is happening and what is necessary. We listen to the sales people, because they are in regular contact with the customers within the market. They often inform us on what direction the market is heading towards. Additionally, we follow the media and try to figure out what the future will be. The best part of this job is developing ideas and to launch a project until we achieve the final product or service.

How did the ‘calcined clay’ project start?

Calcined clay is a good example of a R&D project, this idea came a long time ago, when I was in a meeting and listened to a talk about metakaolin, which is a pure calcined kaolin clay. With the brief explanation presented, I thought that we could make something similar, since we had similar materials and the process already in place. If we could produce the calcined clay, we would be capable of using this to replace cement. With this initial idea, I started studying the process before we passed it to the pilot production team and we began conducting tests.

Has the initiative of sustainability played an important part during the project? Why?

When we are conducting a R&D project, one of the goals is to be better and make improvements, so sustainable thinking is always present in new R&D projects, and this project was no different.

Calcined clay can be used to replace cement. As we know, to produce cement it is necessary to burn fuels, usually fossil fuels like coal which generates a huge amount of CO2 emission. Additionally, during the production process of cement more CO2 is released chemically from the raw materials which increases the total amount of CO2 emitted. Through using calcined clay as a raw material, it will be possible to reduce CO2 emission from 10% to 40%, depending on the replacement rate. So, at the same time this was one of the key drivers for this project. Additionally, through applying calcined clay it is possible to improve the workability of the concrete and the physical characteristics like compressive strength and segment strength.

Where can the ‘calcined clay’ be used? What are the advantages of using this product?

Calcined clay can be used in many cementitious products, like ready-mix concrete, precast concrete and premixed concrete. So this can be used when it is necessary for a specifically improved performance combined with a lower CO2 emission.

In my opinion, it is a three in one product – improving product performance, reducing the CO2 emission and it is readily available, that’s why calcined clay is a special product.

Is this a unique product or can we find alternatives in the market?

Cementitious material like fly ash and slag has been used in high quantities within the cement industry for a long time. However, these materials will be reduced in availability over time since they are by-products of the coal and steel industries, due to the decrease of production in these industries, the availability of these alternatives are decreasing and in the future they will not be available in the market. On the other hand, it is possible to use volcanic rocks for the same effect, through extracting and milling the rocks, but this type of material can only be found in specific regions of the world, which makes it very difficult for it to be attained. Today alternative products with the same properties of calcined clay do not exist. Making it a unique product.

The construction industry is responsible for 40% of CO2 emissions, how can calcined clay improve the impact of the construction products?

Calcined clay is an important product in the construction industry. In comparison with the typical raw materials, calcined clay as it is made today, will reduce the CO2 emission of cement. Improving the production process of this material, the CO2 reduction will be higher. Additionally, the cement industry is making their own efforts to reduce their CO2 emission, for example through replacing the fossil fuels used. Today calcined clay can reduce by 10% to 40% of the total CO2 emission of typical Portland cement production, but furthermore, the impact in the future as you can see will be huge. This transition will make a significant difference in the construction sector.

How is this type of project aligned with the LECA’s goals?

We claim that together we build for the future and a typical R&D project is created to achieve this - we do actually build for the future. All our R&D projects need to be aligned with LECA’s goals to have success. The calcined clay project is a good example of that, improving the performance of products, reducing the CO2 emissions and being readily available.

How are we scientifically aligned with our research? If we want to know more about ‘calcined clay’, where can we find more detailed information?

We work and liaise with many Universities and experts during all our developments and we still continue to do so. We are writing and launching papers and present them regularly. This year we have papers at the conference in Lausanne and Milano.

I am always available for contact should anyone need to know more about our calcined clay product. In our specific brochures and guides, it is possible to find relevant articles and we regularly attend industry specific conferences to talk about our new products and developments.


Geir Norden

Senior R&D Manager



Interview with Geir Norden

Overview on Calcined clay

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