Iron oxide can also be used to restore the reduced iron . Reduction of iron oxide scale manufacturing production processes generally divided into coarse and fine reduction reduction . The iron oxide at about 1100 ℃ coarsely restore process to restore w (Fe> 95%, w (C <0.5% of the sponge iron ; then pulverizing the resulting block of sponge iron at a temperature of 800 ~ 1000 ℃ in in an atmosphere of pure hydrogen or ammonia decomposition , for fine reduction . Finally, pulverized and sieved to adjust the particle size , made of iron .
　Iron oxide powder metallurgy raw material used to produce a reduced iron powder used . Containing iron oxide is reduced to w ( more Fe98% of sponge iron by slag , crushing, magnetic separation after screening , for fine reduction, reduced iron production of qualified and then finely ground into the mill by grading sieve to get different granularity of high purity iron . finer granularity of the key components for the production of iron equipment , just die , to a molding, high strength , wear-resistant , corrosion-resistant parts , can be used in the defense industry, aerospace manufacturing , transportation , oil exploration and other important industries. coarser iron powder can be used in the production of welding electrodes .
( 1 ) is used as the raw material of iron or steel sintering aid to help melt slag agent.
　FeO content in the oxide scale up to more than 50 %, which is better assisted sintering iron-containing materials , theoretical results show that , 1kgFeO exothermic oxidation of Fe2O3 to 1973 joules. After sintering the mix with added iron skin, due to the high temperature sintering process fully , so sintering productivity , solid fuel consumption down . Production practice shows that 8% of the oxide scale can yield about 2%. Baosteel use of iron oxide as an auxiliary material, mix with addition of iron ore in the skin, on the one hand , due to the relatively large iron oxide particle to improve the permeability of the sinter bed ; hand, iron oxide during sintering heat thereby reducing the consumption of solid fuel .
In addition . The use of iron oxide can be used as a flux for fluxing ore , used in steelmaking . Co- melting of iron oxide is used as slag-forming agent is a highly efficient smelting fluxing material steel to improve efficiency and reduce coke, coal consumption and prolong the life of the converter furnace .
( 2 ) Alternative smelting ferrosilicon alloy steel scrap or scrap substitute for steelmaking furnace .
　Smelting ferrosilicon alloy steel scrap is an important raw material for the smelting of ferroalloys annual cuttings about 2 million tons of steel , and the steel industry waste each year about 10 million tons of iron oxide . Alternative has been developed with the iron oxide silicon alloy steel scrap smelting of new technology, and achieved good economic results.
EAF requires scrap as raw material, scrap steel material for more stringent requirements , but such a small number of scrap steel , high prices , lack of supply. At low prices and a wide range of sources of iron oxide , steel slag and other waste as the main raw material , replace the less high prices of scrap , with significant economic benefits.