About Lantan

Coke for calcium carbide is used as conductor and heat in electric arc furnaces for producing calcium carbide. Calcium carbide is added into the electric arc furnace with coke. Under the action of high temperatures (1800-2200°C) of arc heat and resistance heat, a complex reaction occurs with the limestone to generate calcium carbide (carbide) in a molten state. The generation process can be expressed by the following response formula: CaO+3C→CaC2+CO-46.52KJ The coke used for calcium carbide should have the characteristics of low ash content, high reactivity, large resistivity and moderate particle size. It should also remove powder and reduce moisture as much as possible. Its chemical composition and particle size should generally meet the following requirements: The fixed carbon is greater than 84%, the ash content is less than 14%, the volatile content is less than 2%, and the sulfur content is less than 1. 5%, phosphorus content is less than 0.04%, moisture is less than 1.0%, the particle size is determined according to the capacity of the electric arc furnace for producing calcium carbide: Electric furnace capacity/KV·A Particle size/mm ＜5000 3-12 5000-10000 3-15 10000-20000 3-18 ＞20000 3-20 The particle size qualification rate is required to be above 90%.

Ferroalloy coke is coke used for smelting ferroalloys in submerged arc furnaces. Ferroalloy coke participates in the reduction reaction as a solid reducing agent in the submerged arc furnace, and the reaction mainly takes place in the high-temperature zone in the middle and lower part of the furnace. Taking the smelting of ferrous alloys as an example, the reaction formula is SiO2 (liquid) + 2C (solid) = Si (liquid) + 2CO (gas). As the reaction proceeds, the fixed carbon in the coke is continuously consumed and mainly escapes from the furnace top in the form of CO. Some or most of the aluminum oxide, iron oxide, calcium oxide, magnesium oxide and phosphorus pentoxide in the coke ash are reduced and enter the alloy. ； The unreacted part enters the slag. The sulfur and silicon in the coke generate silicon sulfide and silicon disulfide and then evaporate. Smelting different types of ferroalloys has different requirements for coke quality. When producing ferrosilicon alloys, the requirements for coke quality are the highest, so ferroalloy coke that can meet the production of ferrosilicon alloys can generally meet the requirements of other ferroalloys. 　　The requirements for coke in ferrosilicon alloy production are: The fixed carbon content is high, the ash content is low, the content of harmful substances such as aluminum oxide and phosphorus pentoxide in the ash is small, the coke has good reactivity, the coke resistivity, especially the high temperature resistivity, is large, the volatile content is low, it has appropriate strength and grain size, and the water content is low and stable. 　　China Metallurgical Standard (YB/T034-92) stipulates the technical requirements for ferroalloy coke, requiring particle sizes of 2-8mm, 8-20mm, and 8-25mm.