Ferro-alloys are usually produced by the reduction of a metallic ore (generally oxide)
High carbon ferro-manganese is produced by the reduction of manganese ore by carbon, in electric submerged-arc furnaces or in blast furnaces.
Medium and low carbon ferro-manganese are produced either by refining high carbon FeMn or by using silico-manganese as a raw material.
Silico-manganese is produced by silico-thermic reduction, in electric submerged-arc furnaces, using manganese ores and/or slags from the production of ferro-manganese.
Silicon is commonly produced by a "Submerged Arc Furnace". Polycrystalline silicon (PCS), a hyper form of Silicon (99.9999999), is produced for semi-conductors and solar cells by a chlorination process in a special reactor metallurgical-grade silicon followed by a reaction in the presence of hydrogen at high temperatures.
A very pure Silicon is also produced by a patented hydrometallurgical process. This process removes the impurities in high silicon by treatment in an iron chloride solution, followed by a further purification process.
Silica Fume is produced during the manufacture of silicon or ferrosilicon. This electro-metallurgical process involves the reduction of quartz. Silica fume is formed when SiO gas is oxidised to SiO2. A dedicated Website has been developed for Silica Fume outlining its properties, applications and related standards: www.microsilicafume.eu
Depending on the alloying element, the grade and other economic/technological considerations, the details of the production processes can vary widely.
A comprehensive description of existing processes can be found in Best Available Techniques (BAT) Reference Document for the Non-Ferrous Metals Industries developed within the legislative framework of the Industrial Emissions Directive (/sites/default/files/2020-01/JRC107041_NFM_bref2017.pdf).
In all cases, the production of Ferro-alloys and Silicon is an energy-intensive activity, and EUROALLIAGES' Members are committed to constantly improving their operations in order to save energy and to reduce greenhouse gas emissions: the European plants are among the most efficient in the world, helping to provide users with the necessary supply of ferro-alloys and Silicon with minimal impact on natural resources.
The European Ferro-alloys and Silicon industry has developed and improved its technology and production processes, not only by improving the quality of the materials delivered to its customers, but also by improving working conditions and by implementing the best available technologies to reduce environmental impact. This industry provides its employees and consumers with the highest social, safety, environmental and occupational health standards.