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Existing equipment conditions for Xuanhua Steel, through a combination of thermodynamic equilibrium of theoretical analysis and laboratory experiments and industrial experimental method, optimized to improve the smelting process, to select the best slagging system and smelting process, proposed a Xuanhua Steel new smelting process method. Laboratory thermodynamic equilibrium experiments carried a novel composite dephosphorizer the developed as well as reaction thermodynamic calculations and analysis, alkalinity study dephosphorizer, flux types and ratio and other factors dephosphorization rate converter composite dephosphorization slagging agent and provide technical support to the smelting process optimization. Xuanhua Steel site industrial test the main converter pre-slagging system, gun-bit system, the bottom blowing system, composite slagging agent feeding system pre dephosphorization, develop best Dephosphorization efficient process route. Investigated slagging the appropriate time, the amount of slag in the furnace to maintain a minimum amount of slag, while the highest dephosphorization efficiency. Optimization of the the late small residue decarbonization process system, and explore some late fewer smelting slag smelting smelting characteristics. The laboratory SiC high-temperature furnace, CaO-Fe2O3-CaF2-CaCl2-based powdered dephosphorizer new dephosphorizer high temperature experiments. Obtained by experiment: flux CaCl2 and CaF2 dephosphorization of the effect of any one is better than the single use. 1300 ℃, the basicity R = 2, the proportion of CaCl2 and CaF2 In dephosphorizer, to 3.65%, the dephosphorization effect better, dephosphorization rate of 90%; caustic sludge instead of CaCl2 for hot metal dephosphorization, alkali effect of slag mixed fluorite the dephosphorization effects than used alone caustic sludge; containing the pair hot metal dephosphorization time, 14.8% of caustic sludge and 5.99% CaF2 prepared dephosphorizer dephosphorization rate reached 86%. The experiments also proved that the addition of BaO dephosphorizer can significantly lower the melting point of slag conducive rephosphorization small extent. Through live production test showed: smelting of the new process, high carbon steel, the balance of the composition and temperature of better coordination, pre deslagging dephosphorization rate of about 60%, the endpoint, steel [C] to 0.4%, [P 0.006%, about 95% of the dephosphorization rate. Containing CaCl2 of caustic sludge as dephosphorizer dephosphorization, can reach the same level. The same kinds of steel smelting, smelting new technology compared to conventional smelting furnace steel quantity is reduced by about 3t. Slag microstructure analysis, uniform the converter slag composition of the new technology, the high melting point of the initial slag less, the end of tricalcium silicate slag slag, the use of the the soda residue after facies distribution is relatively uniform endpoint ingredients conducive to slag splashing furnace protection.
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