Vision Steel Converter Efficient Dephosphorization New Technology Research,

The smelting process of converter is optimized and improved through the method of theoretical analysis of thermodynamic equilibrium and the laboratory experiments combined with industrial experiments in Xuan Steel.A fit new type of converter smelting process is declared by selecting the best slagging system and smelting process.The new compound dephosphorization agent and reaction thermodynamic calculation and analysis are carried out by thermodynamic equilibrium laboratory experiments. Dephosphorization alkalinity agent, flux type, ratio and other factors on the impact of dephosphorization rate is researched to provide the technical support for application of composite converter dephosphorization slagging agent and smelting process optimization.Industrial experiments of Xuan Steel's site were operated that pre-main converter slagging system, gun system, bottom blowing system, composite slagging agent charging system and other factors on the impact of pre-dephosphorization to develop the best technology route for dephosphorization efficient. The appropriate slagging time, the volume of slag were studied so that the furnace has the smallest amount of residue, while the highest efficiency of dephosphorization. Optimize the latter less-residue decarbonization technology system and explore the smelting characteristics of latter less-residue smelting converter.The high-temperature experiments were operated in SiC high-temperature laboratory furnace using CaO-Fe2O3-CaF2-CaCl2-based powder dephosphorization agents,which research alkalinity,flux type and ratio on the rate of hot metal dephosphorization.It is obtained through experiments that using CaCl2 and CaF2 flux is more effective than either used alone.At 1300℃; R=2,CaCl2 and CaF2 at dephosphorization agent in a ratio of 3.65%, dephosphorization effect is better;the use of alkali slag in place of CaCl2 for dephosphorization of hot metal, the alkali slag mixed with fluorite dephosphorization is more effective than alkali slag alone, with 14.8% of the alkali slag and 5.99% of CaF2 prepared dephosphorization agent, the dephosphorization rate of molten iron reachs to 86%. Experiments also proved that adding BaO dephosphorization agent can significantly reduce the melting point, and is conducive of melting slag, avoiding rephosphorization.It is cleared that the medium&high-carbon steel can be better produced using the new smelting process,which dephosphorization ratio at about 60%;at the end of the steelmaking,[C] for 0.4%, [P] for 0.006%,dephosphorization rate at 95% through on-site production.The same dephosphorization effect can be achieved instead of CaCl2 by the alkali slag as part of dephosphorization agentl. For same kinds of smelting steel, the average material compared to normal steel smelting,the amount is reduced by about 3t.Microstructure analysis of slag, we can see that composition is uniform for converter slag of the new technology, few high melting point phase of the initial slag, mainly calcium silicate slag of the end slag. It is conducive to converter splash protection to the uniform composition for lithofacies distribution of the end of slag after the use of alkali slag.