FeV40
Using 75% ferrosilicon and a small amount of aluminum as the reducing agent, the flake Vanadium pentoxide produced by the electrosilicothermal method is refined into qualified products through two stages of reduction and refining in an alkaline electric arc furnace. During the reduction period, all the reducing agents in one furnace and flake Vanadium pentoxide accounting for 60 to 70% of the total amount are loaded into the electric furnace, and silicon thermal reduction is performed under high calcium oxide slag. When the V2O5 in the slag is less than 0.35%, the slag (called lean slag, which can be discarded or used as building materials) is discharged and transferred to the refining stage. At this time, add flake Vanadium pentoxide and lime to remove excess silicon, aluminum, etc. in the alloy liquid. When the alloy composition meets the requirements, slag and ferroalloys can be produced. The slag released in the later stage of refining is called rich slag (V2O5 content is as high as 8 to 12%), which is recycled when the next furnace starts charging. The alloy liquid is generally cast into cylindrical ingots, which are then cooled, demoulded, crushed, and slag removed to become finished products. This method is usually used to smelt ferrovanadium containing 40 to 60% vanadium. The recovery rate of vanadium can reach 98%. The power consumption for refining ferrovanadium per ton is approximately 1,600 kW·H.
FeV60
The thermite method uses aluminum as the reducing agent and uses a low ignition method to smelt in a furnace barrel lined with an alkaline furnace. First, a small part of the mixed charge is put into the reactor, which is ignited. After the reaction begins, the remaining charges are added sequentially. It is usually used to smelt high-vanadium iron (containing 60-80% vanadium). The recovery rate is slightly lower than that of electrosilicothermal method, about 90-95%.
FeV80
The role of ferrovanadium:
Ferrovanadium is an important alloy additive in the steel industry. Vanadium increases steel's strength, toughness, ductility and heat resistance. The use of vanadium in the steel industry has increased dramatically since the 1960s, accounting for 85% of vanadium consumption by 1988. The consumption of vanadium in steel accounts for 20% of carbon steel, 25% of high-strength low-alloy steel, 20% of alloy steel and 15% of tool steel. Vanadium-containing high-strength low-alloy steel (HSLA) is widely used in the production and construction of oil and gas pipelines, buildings, bridges, tracks, pressure vessels, frames, etc. due to its high strength. At present, the application range of various vanadium-containing steels is getting wider and wider, and relevant talents are becoming more and more important.
Vanadium is mainly used in non-ferrous metal alloys to produce vanadium-titanium alloys such as Ti-6Al-4V, Ti-6Al-6v-2sn and Ti-8al-1v-mo. Ti-6Al-4V alloy is an excellent high-temperature structural material used in the manufacture of aircraft and rockets. It is highly valued in the United States, where production accounts for more than half of titanium-based vanadium alloys. Vanadium is also used in magnetic materials, cast iron, carbide, superconducting materials and nuclear reactor materials.
