Experiment Research On Siliceous Substitute Scrap Smelting Fe Si75

Ferrosilicon main as a deoxidizer and alloying agents in the steelmaking process, especially FeSi75 is the most widely used, it has a very important position in the steel industry. At present, a large number of ferrosilicon are using traditional techniques for smelting, even steel scrap, silica and coke as a raw material using a continuous manner heating in the submerged arc furnace smelting without slag, and due to the current price of steel scrap as one of the rising raw material, so the cost of smelting ferrosilicon smelting instant critical reduced.Using steel scrap smelting alternatives have been successful examples, this paper using high silicon grade iron ore in a mine in Hunan Qidong – siliceous substitute steel scrap iron smelting ferrosilicon FeSi75. First, theoretical calculations and analysis the feasibility smelting ferrosilicon FeSi75 with siliceous instead of steel scrap, and get the ratio of raw materials, research the process of using Coke reduct silica by TGA TGDSC experment, determining the siliceous at 623 K, 773 K, 1073 K, 1273 K, 1473 K phase will change, significant weight loss. Through argon, respectively, in the temperature points were analyzed by XRD results : The following 1073 K Fe2O3 start into Fe3O4, and 1073-11273 K, Fe3O4 began to become FeO, as well as, at this temperature,a part of SiO2 there are also will be converted to SiC.Smelting experiment using w(SiO2)=36.4%,w(TFe)=31.58%, w(P)=0.15% siliceous instead of steel scrap performed on transformer capacity 300 kVA, submerged arc furnace secondary voltage of 50 V, the test results obtained FeSi75 ferrosilicon w(P)> 0.04%, but the chemical composition conforming to the chemical composition of the standard FeSi75-B, while coke dosed than traditional smelting process to be more, the power consumption increases slightly, but all sides economic indicators, instead of steel scrap smelting ferrosilicon silica has certain advantages.Using CaC2-CaF2 slag system for w(P)>0.04% of FeSi75 ferrosilicon reduction dephosphorization experiment, when the initial carbon content of ferrosilicon wc = 0.2%, the temperature of 1723 K, CaC2: CaF2 = 4: 1, time of 5min,the carbon activity αc = 0.02-0.03, using dephosphorizer CaC2-CaF2 mixed with the FeSi75 ferrosilicon added up to about 12.5%,dephosphorization best, the dephosphorization rate of 64.4%, but with the initial carbon content increases, the dephosphorization rate was gradually decreased.