General Outline of Vanadium Ores

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Vanadium content in the earth’s crust is about 0.02% of the weight of the earth’s crust, widely distributed but scattered. Vanadium ores have been found more than 70 species, among which, patronite, roscoelite and descloizite contain vanadium oxide up to 8-20%. Vanadium-titanium magnetite is low grade, generally containing V2O5 of 0.2-1.4%, but it is the main raw material for the vanadium extraction with its largest reserves exceeding 40 billion tons all over the world.

Vanadium-iron magnetite and vanadium resources are quite abundant. More than 40 billion tons of vanadium-iron magnetite has been identified all over the world, mainly distributing in a few countries including Russia, America, China and South Africa. It primarily exists in vanadium-titanium magnetite, phosphate rock, sandstone containing uranium and siltstone deposits. In addition, there is also a large number of vanadium existing in bauxite, carbonaceous crude oil, coal, and oil shale as well as tar sands.

Statistics from the U.S. Bureau of Mines show that at the current mining scale, explored vanadium resources can be exploited for 150 years, mainly in South Africa, Asia, North America and other regions (South Africa accounting for 47.0%, Russia for 24.6%, America for 13.1%, China for 9.8%, the sum of the other countries accounting for less than 6%).

With good plasticity and malleability, vanadium can be made into sheets, wires and foil at room temperature. However, these products contain small amounts of impurities, particularly interstitial elements (such as carbon, hydrogen, oxygen and nitrogen), which can significantly affect physical properties of vanadium. For example, vanadium’s plasticity will reduce if vanadium containing hydrogen of 0.01% causes an embrittlement; if its carbon content is up to 2.7%, its melting point will rise to 2,458°F. Vanadium can be used as structural materials for its high melting point, hardness and resistivity; weak paramagnetism; small linear expansion coefficient; density and modulus of elasticity similar to steel.

Vanadium is one of important strategic materials, mainly used in the metallurgical industry. As alloying element additives, vanadium metal and vanadium metal powder not only improve steel’s structures and properties, but also enhance its strength and toughness. Secondly, vanadium can be made into high-temperature and high-strength alloy with titanium. And in the chemical industry, vanadium oxide is used for the production of catalysts, etc.

Internationally vanadium’s extraction basically recycles from by-products. For example, South Africa, Finland, Russia and other countries recycle from the vanadium-titanium magnetite in the ironmaking; American most recycles from carnotite and phosphosiderite; Canada recycles from the dust collected in the burning of petroleum coke; a few countries also extract vanadium from stone coal. In short, the world’s vanadium mainly recycles from vanadium-titanium magnetite.

Vanadium products can be divided into primary products, secondary products and three-level products. Primary products are: vanadium minerals, concentrate ore, vanadium slag, waste catalysts refined by waste oil, etc. Secondary products include vanadium pentoxide, or an industrial product used as a catalyst for the production of sulfuric acid and petroleum refining. Three-level products include ferrovanadium, vanadium aluminum alloy, molybdenum vanadium aluminum alloy as well as vanadium compound; among which, ferrovanadium is the most important vanadium materials, accounting for 85% of the vanadium consumption. Ferrovanadium can be divided into two categories of 50-60% and 70-85% based on standards by countries.

China’s vanadium industry started in the 1950s. Workshop for vanadium extraction of Jinzhou Ferroalloy Factory restored and expanded in 1958, with vanadium-titanium magnetite concentrate from Chengde city as raw materials. China’s other plants for vanadium extractions have been put into operation after 1960. In 1970, Panzhihua Iron and Steel Company was completed and put into operation. From then on, China’s vanadium industry has entered a new historical stage. Until 1980, China has become one of the major vanadium producers all over the world, but also can produce a variety of vanadium products. In addition, vanadium’s promotion and application have made a faster development.