Portland cement clinker production consumes large amounts of natural resources, mostly limestone and clay, but also sand and iron additives. Nowadays, the cement industry is facing the challenge of protecting the environment by decreasing the consumption of natural raw materials. Various industrial solid wastes have been utilized as alternative raw materials in Portland cement clinker production. Iron-silicate fines (ISF) are such alternative material, which can be used as a substitute of the commonly used iron ores. According to the mineral composition of the main raw materials (clay and limestone), ISF could be used as silica and iron corrective material or as a source of iron.
There are several benefits of ISF valorisation in the cement industry:
» Ready-to-use source of iron;
» No need for additional crushing and grinding;
» Suitable for both dry and wet clinker production lines;
» Good mixing properties;
» Promote lower calcination temperature;
» Eliminate the need for mineralizers.
The chemical composition of the material includes the minerals fayalite, magnetite, pyroxene and quartz, basically in the form of ferrous and silica dioxide, which give the name of the material – iron-silicate.
46,0% (Fe2O3>60 %)
ISF contractors are: Heidelberg Cement, Lafarge Holcim, Titan, American Cement, etc.