Andrey Korablin, Founder, SmartScrap, and Olli Hänninen, Owner and Co-founder, Moviator Oy, in a joint interview with Kanika Mathur, discuss how their collaboration is revolutionising the use of metallurgical slag in cement production.
The cement industry is undergoing a transformative shift towards sustainability, driven by the need to reduce carbon emissions and optimise raw material usage. One of the most promising advancements in this space is the use of metallurgical slag as an alternative raw material, a practice that not only reduces reliance on virgin resources but also contributes to significant environmental benefits. In this exclusive interview, Andrey Korablin of SmartScrap and Olli Hänninen of Moviator Oy share insights into their strategic partnership, the advantages of slag utilisation
and the future of alternative raw materials in
cement manufacturing.
Tell us about Moviator Oy’s collaboration with SmartScrap.
Hänninen: I believe innovation thrives through strong partnerships. That’s why I am excited to collaborate with Smartscrap, a leader in sourcing high-quality recyclable materials. Meeting Andrey from Smartscrap has been inspiring—his expertise aligns perfectly with our mission to provide the best solutions such as crushers, pre-grinders and fine grinding mills for efficient material processing.
Together, we are unlocking new opportunities in the slag and cement industry. By combining Smartscrap’s material access with Moviator’s technology, we’re driving sustainability and maximising raw material value!
How does SmartScrap contribute to the use of metallurgical slag as an alternative raw material in cement production?
Korablin: We are actively searching for old slag piles and negotiating their acquisition. In some cases, discussions are already underway. Our goal is to process these slag piles and produce materials that meet the specific requirements of our customers.
Before starting production, we engage in discussions with cement plants in neighbouring regions, sharing best practices for slag utilisation. One of our key contributions is identifying top experts and best practices in using slag for cement production and promoting their adoption across the industry.
How does Moviator contribute to the use of metallurgical slag as an alternative raw material in cement production?
Hänninen: Moviator processes metallurgical slag using advanced crushing and grinding technology, refining the mineral portion into a high-quality raw material for cement production.
What are the key advantages of using slag over traditional raw materials in cement manufacturing?
Korablin: The key advantage of using slag today is its ability to reduce CO2 emissions. Cement production relies on four key oxides: calcium oxide, silicon oxide, aluminum oxide and iron oxide—all of which are present in slag. Since slag has already undergone thermal treatment, its use in cement manufacturing requires less energy. As a result, producing cement with slag generates lower CO2 emissions.
For example, one cement plant we work with incorporates 30 per cent of slag into its production, consuming 700,000 tonnes of slag annually. This is a significant volume for a single plant.
By replacing 30 per cent of their raw materials with slag, they have reduced their CO2 emissions by 20 per cent compared to alternative materials.
Hänninen: Slag improves durability, strength and sulphate resistance while reducing CO2 emissions and reliance on virgin materials.
How do you ensure the quality and consistency of slag used in the cement industry?
Korablin: It is crucial to choose a supplier that prioritises product quality and long-term partnerships.
Let’s take an example: In the first scenario, slag from a single furnace is mixed with slag produced in other furnaces. However, these slags are usually quite uniform. This is because metallurgical plants typically produce the same type of product using consistent raw materials over many years, resulting in homogeneous slag.
In the second scenario, if slag is mixed from different sources, the situation changes. However, even in this case, it is still possible to assess and map the distribution of slag from various furnaces.
Regardless of the source, both the supplier and the cement plant must implement quality control measures. Slag is a bulk material, and after production, it remains relatively uniform. Sampling and testing processes can be organised effectively, making quality management a fully solvable task.
Hänninen: Moviator employs precision processing, magnetic separation, and strict quality controls to ensure consistent chemical composition and fineness.
What challenges do you face in sourcing, processing, and supplying slag for cement production?
Korablin: One of the biggest challenges is the human factor. Unfortunately, in many industrial enterprises, people are resistant to change. This is not only because mid-level employees are reluctant to adapt but also due to a lack of proper motivation for using alternative raw materials. In many cases, alternative materials can initially lead to lower productivity or increased energy consumption.
These factors directly impact key performance indicators (KPIs) for employees. If using alternative raw materials negatively affects these KPIs, it can also reduce their salaries. Additionally, there is little incentive for employees to seek alternative solutions—if their initiative proves successful, they may receive no financial reward. However, if they make a mistake, they could be demotivated or even risk losing
their jobs.
This is why, at the top management level, it is crucial to create a system of motivation and a company culture that encourages change and innovation.
I’ll share an example from a cement plant I recently visited. During our discussion, they stated that cement plants can work with a wide variety of slags. Depending on the slag’s quality and chemical composition, different proportions can be used in the mix. However, their company’s strategy is to prioritise alternative raw materials as long as they are as cost-effective as natural ones and meet safety requirements. Their reasoning is that it supports sustainability and expands their sourcing options.
This kind of approach is rare rather than common. Once again, the biggest challenge remains the lack of motivation among many companies to adopt alternative raw materials.
Hänninen: Challenges include chemical variability, volume instability and environmental compliance, requiring careful selection and processing.
How does using slag in cement impact sustainability and carbon emissions reduction?
Korablin: I’ve already addressed this question earlier, but to reiterate—using the example of a cement plant that incorporates 700,000 tonnes of slag annually (30 per cent of the raw material mix), the CO2 emissions reduction amounts to 20 per cent.
Hänninen: Slag replaces clinker, significantly reducing CO2 emissions, energy consumption and industrial waste.
Can you share insights into global trends in metallurgical waste recycling for cement applications?
Korablin: This involves using alternative raw materials that contain the necessary oxides—calcium oxide, silicon oxide, aluminum oxide and iron oxide. These can include fly ash from thermal power plants, aluminum production waste as a source of aluminum oxide, foundry sand as a source of silicon, and slag, which contains all four oxides.
Another key trend is the additional processing of raw materials before they reach the cement plant. Suppliers are expected to take on more responsibility in preparing materials, potentially including pre-grinding. This helps reduce the reliance on energy-intensive ball mills at cement plants. When suppliers are more involved in the cement production process, the supply chain becomes stronger and more efficient.
Hänninen: The industry is increasingly adopting blast furnace and steel slags as supplementary cementitious materials (SCMs) to enhance sustainability. The trend is clearly shifting towards finer particle sizes, such as 600 Blaine, to enhance the strength and durability of concrete.
What role does SmartScrap play in educating and supporting cement manufacturers in adopting alternative raw materials?
Korablin: This is about spreading best practices. We have been working with alternative raw materials since 2011, starting with metallurgy as the main driver for slag recycling. Over the years, we’ve gained deep expertise and connected with specialists who help steel plants integrate alternative raw materials. Now, we’re applying the same approach to the cement industry.
We identify the best solutions—from raw material preparation, including crushing and grinding, to material selection for cement plants and quality control throughout the process.
Our role is to introduce cement producers to industry-leading practices. To achieve this, we host webinars featuring top experts who share their knowledge and experience. Additionally, we develop online courses on slag recycling and building a sustainable business around it.
What role does Moviator play in educating and supporting cement manufacturers in adopting alternative raw materials?
Hänninen: Moviator provides technical expertise, testing, and innovative grinding solutions to help cement manufacturers integrate alternative materials efficiently.
What innovations do you foresee in the future of alternative raw materials for the cement industry?
Korablin: It feels like we live in an era of innovation, yet we struggle to keep up with it. So many advancements have been made, but we often fail to fully utilise them. Take a smartphone, for example—we probably use only five per cent of its capabilities. The same applies here.
Even in the age of artificial intelligence, we believe in the critical role of people in production—their ability to implement changes, find new solutions and adopt alternative raw materials. The real innovation, in my view, lies in building a corporate culture that can quickly adapt to today’s fast-changing environment. Large enterprises, in particular, need flexible and agile teams.
Perhaps this isn’t the most conventional answer, but I see the most significant innovations happening in change management. And to me, that’s absolutely crucial.
Hänninen: Future innovations include clinker-free cements, ultra-fine grinding technologies and optimised SCM blends for lower carbon and high-performance materials.