The Flodin process is a direct reduction process for manufacturing modern

iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...

and steel, developed by Gustaf Henning Flodin from Sweden and patented in 1924. It has been used in

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and t ...

, Sweden, and the United States. Using a specially constructed

electric arc furnace An electric arc furnace (EAF) is a furnace that heats material by means of an electric arc. Industrial arc furnaces range in size from small units of approximately one-tonne capacity (used in foundries for producing cast iron products) up to ...

, a mixture of

hematite Hematite (), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of ...

with +0.2% carbon content and

coal Coal is a combustible black or brownish-black sedimentary rock, formed as stratum, rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen ...

(or charcoal) is

smelted Smelting is a process of applying heat to ore, to extract a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals. Smelting uses heat and a ch ...

in a continuous process, with the reduced metal accumulating at the bottom of the furnace, where it can be tapped off. Carbon content in the product can be controlled by changing the quantity of coal in the furnace. Noncorroding chromium steel could also be produced by using impure ore instead of hematite. Likewise, spongy iron can be cast by using coal-lime

briquettes A briquette (; also spelled briquet) is a compressed block of coal dust or other combustible biomass material (e.g. charcoal, sawdust, wood chips, peat, or paper) used for fuel and kindling to start a fire. The term derives from the French word ' ...

. Additionally, the Flodin furnace also can be used to produce so-called 'soft steel'.

References

Steelmaking Swedish inventions {{Industry-stub