Study on Si Transfer Mechanism in a Blast Furnace

An induction furnace was used for melting and CO gas was introduced.1. < sio_2 > reduction byslag-metal reaction.The Si reduction rate between CaO- < sio_2 > - < al_2_3 > -0-5%FeO(-MgO) slag andcarbon-saturated iron melt measured by the use of < al_2_3 > or graphite crucible. Silicareduction rate was controlled by the Si transfer in metal. the oxidation of Si in metal wascontrolled by the FeO transfer in slag. the effect of FeO on the progress of Si reduction betweenslag and metal was investigated in terms of the change in oxygen potential at the slag/metalinterface. It was found that < sio_2 > can be reduced from slags with FeO of less than 2% to theextent of usual content of Si in hot metal （0.2%）因为oxygen potential at slag/metal interface may not be controlled any more by FeO in slag.2SiO generation from blast furnace type slag.The amount of SiO generation by the reaction of CaO-< sio_2 > - < al_2_3 > slag with graphite was measured in the temperature range from 1700 - to 1800 - C.rate of SiO generation was controlled by The < sio_2 > transfer in The slag with low activity of< sio 2 >,and by the reaction of C with < sio_2 > in the slag with high activity of < sio_2 > . Addition of SiCincreased the interfacial area between slag and graphite，总amount of SiO generation and particularly the rate of SiO generation at lower temperature。

An induction furnace was used for melting and CO gas was introduced.1. <SiO_2> reduction by slag-metal reaction.The Si reduction rate between CaO- <SiO_2> - <Al_2O_3> -0-5%FeO(-MgO) slag and carbon-saturated iron melt was measured by the use of <Al_2O_3> or graphite crucible. Silica reduction rate was controlled by the Si transfer in metal. The oxidation of Si in metal was controlled by the FeO transfer in slag. The effect of FeO on the progress of Si reduction between slag and metal was investigated in terms of the change in oxygen potential at the slag/metal interface. It was found that <SiO_2> can be reduced from slags with FeO of less than 2% to the extent of usual content of Si in hot metal (0.2%), since the oxygen potential at slag/metal interface may not be controlled any more by FeO in slag.2. SiO generation from blast furnace type slag.The amount of SiO generation by the reaction of CaO- <SiO_2> - <Al_2O_3> slag with graphite was measured in the temperature range from 1700゜ to 1800゜C. The rate of SiO generation was controlled by the <SiO_2> transfer in the slag with low activity of <SiO_2> , and by the reaction of C with <SiO_2> in the slag with high activity of <SiO_2> . Addition of SiC increased the interfacial area between slag and graphite, total amount of SiO generation and particularly the rate of SiO generation at lower temperature.