Let’s cement the foundations for decarbonization
Concrete is the most widely used material on our planet after water, but the process of making its main component, cement, which requires the extraction of raw materials and very high temperatures to process them, is responsible for 7.5% of all man-made carbon dioxide emissions.
Which is why a discovery that makes it possible to add used concrete to the process of recycling steel, which both purifies the metal and produces reactivated cement, is so potentially important. If, in addition, this is done using renewable energy, as more and more metallurgical companies are beginning to do (and if they don’t they should be heavily taxed), then we are talking about carbon-free cement and a significant reduction in emissions.
Basically, the process involves crushing used concrete, separating it from the sand and gravel that was added during the manufacturing process, then heating it to remove the water, allowing the resulting clinker to be reused. What’s more, electric arc blast furnaces require a flux material, usually lime, to purify the steel: the substance that is added as a…