Steel can be recycled many times without loss, on top of that it’s production process is clean; hardly any other material complies to the principle of sustainability and social responsibility as steel does.
Therefore steel represents a substantial column of a sustainable society. No other product is actually produced as environmental friendly as steel and performs such an important contribution to the protection of the climate and the environment, thanks to its numerous applications and utilizations. Due to its recycling possibilities, steel contributes to an extraordinary degree to a sustainable use of resources, which are not illimited and must therefore be protected, to keep them for future generations. As a matter of fact steel is the most recycled material in the world. When steel has fulfilled its scope of application after dozens of years, it becomes a high value raw material as scrap, which can be totally recycled without loss as many times as wished and than reintroduced into the economic cycle without remnants. All over the world there are steel mills, among which also the plants of the Riva Group in Germany, that reintroduce old steel products into the production process.
Each steel product is a typical recycling product: for example, in every car there is steel that in its former life was a washing machine, a bycicle or a beverage can. Steel scrap is collected all over the world and then totally recycled. After several recyclings („multi-recycling“) a sum of 4 tons of new steel products are produced out of one ton of steel. Each ton of recycled steel avoids the mining of 1,5 tons of iron ore. Even the byproducts generated in the production of steel can be widely recycled, as raw material, building material or as fertilizer, and are thus reintroduced in to the material cycle. For example, iron slag is used in the cement industry and in road construction. Fertilizers are also important byproducts of the steel industry, and iron oxides are used in the varnish industry as pigment and as magnetizing material for hard disks. Tar, a byproduct of the production of coke, is used in road construction. Iron slags are used as substitute material for limestone, splitt and other natural materias.
As a matter of fact, the use of one ton of steel scrap saves the same amount of greenhouse gas emissions. Thanks to the steel recycling in Germany each year more than 20 million tons of CO2 are avoided. This is the same amount that the city of Berlin is emitting in the year in one year. Morever, due to its multi-recycling the ecologic fingerprint of steel is reduced with each stadium of recacling. The CO2 emissions of the production of 1 ton of steel are reduced by 50 % through multi recycling over a number of life cycles compared to the primary production of steel. In total, in the last 15 years in Germany the CO2 emission was reduced by approx. 20% with reference to the total raw steel production.
A contributuion to the protection of the climate can even come from the use of metallurgical slag. For example, about 85% of the blast furnace slag is used, after comminution, as metallurgical sand for the production of cement. During this process, about 1 ton CO2 for each ton cement klinker brick is saved, because using metallurgical sand there is no need for burning. Concerning the dust emission ,the German steel industry was able to reach considerable reductions in the last decades. Thanks to the introduction of the secondary dedusting systems and to new cleaning technologies and to many more process improvements, the specific dust emissions were reduced by 80 % since 1980.