LD-Slag (named after the Linz-Donawitz steel manufacturing process) is a rock-like by-product of the steel industry. Recent research has shown that a new concrete-like material (carbstone) can be formed, using LD-slag and carbon dioxide as a binder.
LD-slag can capture up to 350 kilograms of CO2 per tonne, making it one of the most promising carbon dioxide sinking materials in the concrete industry. The CO2 is taken from industrial waste streams and biofermentation plants. This makes it possible to reintroduce CO2 and steel by-products into the value chain. This process also gives a new life to materials currently considered waste products in both the steel and concrete industry and turns them into sustainable construction materials.
LD-slag normally has little recycling potential in the production of new cement. This is due to their high iron content which affects the stability of new concrete. However, the Carbstone technology developed by VITO & ORBIX reduces risks to the structural integrity of recycled concrete. This could be the first step in the design of a new circular economy of concrete materials.
VITO is an R&D organization specialized in clean technology and sustainable development.