RU2011102068A - METHOD FOR Smelting Low Phosphorus Steel in a Converter - Google Patents

Abstract

 1. A method of smelting low-phosphorus steel in a converter, including feeding molten iron and solid metal charge into the converter, purging the melt with oxygen from above and neutral gas through bottom blowing devices, feeding slag-forming materials, coolers, coolants into the converter, determining the chemical composition of the melt after blowing in the converter, characterized in that a coolant is placed in the converter, the flow rate of which is set according to! M1 = K1 · (K2 · [P] h- [P] p) · (K3 · Tch-K4 · Mch · [Si] h + A); ! where M1 is the coolant flow rate, kg / t of melt; ! K1 - empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt, equal to 20 ÷ 80; %-one; ! K2 is an empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt, equal to 10 ÷ 20; dimensionless; ! [P] h - mass fraction of phosphorus in molten iron, equal to 0.01 ÷ 0.15; %; ! [P] p is the specified mass fraction of phosphorus in the melt after purging, equal to 0.001 ÷ 0.005;%; ! K3 is an empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt equal to (1.0 ÷ 2.0) · 10-4; kg / t ° C; ! Tch is the temperature of molten iron, ° C; ! K4 is an empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt, equal to (1.8 ÷ 3.0) · 10-4; %-one; ! Mch - liquid iron consumption kg / t of melt; ! [Si] h - mass fraction of silicon in molten iron,%; ! A is an empirical value characterizing the physicochemical laws of dephosphorization of the melt, equal to (2.0 ÷ 3.5) · 10-3; kg / t! lime in an amount determined by dependence! M2 = K5 · [Si] h + K6 · M1 / Mh + B; ! where M2 is the consumption of lime, kg / t of melt; ! K5 is an empirical coefficient characterizing the physicochemical laws

Claims (5)

1. A method of smelting low-phosphorous steel in a converter, including feeding cast iron and solid metal charge to the converter, purging the melt with oxygen from above and neutral gas through bottom blowing devices, feeding slag-forming materials, coolers, coolants into the converter, determining the chemical composition of the melt after blowing in the converter, characterized in that a coolant is placed in the converter, the flow rate of which is determined according to M ₁ = K ₁ · (K ₂ · [P] _h - [P] _p ) · (K ₃ · T _h -K ₄ · M _h · [Si] _h + A); where M ₁ - coolant flow rate, kg / t of melt; K ₁ - empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt, equal to 20 ÷ 80; % ^-1 ; K ₂ is an empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt, equal to 10 ÷ 20; dimensionless; [P] _h - mass fraction of phosphorus in molten iron, equal to 0.01 ÷ 0.15; %; [P] _p is the specified mass fraction of phosphorus in the melt after purging, equal to 0.001 ÷ 0.005;%; K ₃ is an empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt equal to (1.0 ÷ 2.0) · 10 ^-4 ; kg / t ° C; T _h - temperature of molten iron, ° C; K ₄ is an empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt, equal to (1.8 ÷ 3.0) · 10 ^-4 ; % ^-1 ; M _h - liquid iron consumption kg / t of melt; [Si] _h - mass fraction of silicon in molten iron,%; A is an empirical value characterizing the physicochemical laws of dephosphorization of the melt, equal to (2.0 ÷ 3.5) · 10 ^-3 ; kg / t lime in the amount determined by dependence M ₂ = K ₅ · [Si] _h + K ₆ · M ₁ / M _h + B; where M ₂ is the consumption of lime, kg / t of melt; K ₅ - empirical coefficient characterizing the physico-chemical laws of lime dissolution, equal to 60 ÷ 70; kg / t%; K ₆ is an empirical coefficient characterizing the physicochemical laws of lime dissolution, equal to 100 ÷ 600; kg / t; M ₁ - flow rate, kg / t of melt; M _h - liquid iron consumption kg / t of melt; [Sij _h - mass fraction of silicon in molten iron,%; B is an empirical value characterizing the physicochemical laws of lime dissolution, equal to 40–70; kg / t cooler in the amount determined by the dependence M ₃ = K ₇ · M ₁ · M _h ; where M ₁ - coolant flow rate, kg / t of melt; M _h - liquid iron consumption kg / t of melt; K ₇ is an empirical coefficient characterizing the physicochemical laws of dephosphorization of the melt equal to (1.0 ÷ 5.0) · 10 ^-3 ; t / kg purge with oxygen from above and neutral gas through bottom purge devices until the mass fraction of carbon is obtained after purging no more than 12 · [P] _p without intermediate loading of slag in a single-slag mode. 2. The method according to claim 1, characterized in that the melt is purged only with oxygen from above. 3. The method according to claim 1, characterized in that ferrosilicon with a silicon content of 40 ÷ 80 wt.% Or a mixture of ferrosilicon with a silicon content of 40 ÷ 80 wt.% And an aluminum-containing material with an aluminum content of 40 ÷ 100 wt.% Is used as a heat carrier. in the following ratio of components in it, wt.%: ferrosilicon 50 ÷ 90 aluminum-containing material 3 ÷ 50 4. The method according to claim 1, characterized in that as the coolers use iron ore pellets or iron ore. 5. The method according to claim 1, characterized in that after carrying out an oxygen purge, lime is fed into the converter in an amount of 1.0 ÷ 5.0 kg / t of melt and a neutral gas is purged for 0.5 ÷ 5.0 min from above through an oxygen lance with a flow rate of 1 ÷ 5 m ³ / t · min and / or through bottom blowing devices with a flow rate of 0.01 ÷ 0.1 m ³ / t · min; argon gas and / or nitrogen are used as a neutral gas.