At Ovako, we are known for our clean and sustainable steel made from recycled steel scrap. We are proud to recycle about 800,000 tons of scrap each year, which makes us one of the largest scrap recyclers in the Nordic countries. The Swedish steel industry’s Vision 2050 states that resources should be used so efficiently that only products of value to the community leave our plants. Ovako conducts ongoing development efforts to identify areas of use for the residual products that arise in the production process of our high-quality steel products, which are world-leading with their low carbon footprint. The goal is always to ensure that they are used where they contribute with the best possible social benefit.
Ovako’s residual products create strong roads
Together with the asphalt industry, Ovako has identified an almost perfect application for residual products. Using slag from Ovako’s steel production as aggregate produces a slag asphalt with unique properties that contribute to low road maintenance costs and increased service life. The asphalt is suitable mainly for surfaces that are exposed to high loads, very heavy traffic, low speeds and where wheels are often turned since it improves the wear resistance and durability of the coating. Roundabouts, industrial areas, parking lots, harbors and other areas with a high proportion of heavy traffic can therefore benefit greatly from slag asphalt.
An early pilot project was carried out at a heavily trafficked crossing inside Ovako’s facility in Hofors. Previously, the wear had been so great that the asphalt needed to be repaired annually, but with the new asphalt composition, no improvement have been needed for over 10 years. This favorable outcome means that Ovako’s slag is now found in a considerable amount of asphalt.
Additional benefits of slag-based asphalt
- Quieter driving – Slag particles absorb tire noise and make the asphalt quieter to drive on.
- Better road surfaces – Unlike ordinary asphalt, which over time becomes slippery to drive on, slag asphalt retains a rough surface, providing better grip when driving.
- Less temperature dependence – The binder in the asphalt is affected by the slag, which means that fewer cracks form in the winter and there is less rutting in the summer.
- More cost-effective – Lasts longer and therefore reduces road maintenance costs.
- More pleasant driving – Reduces the risk of stone chips as the surface does not release stones.