A kinetic study of the reaction between hot metal and soda ash

铁水与纯碱反应的动力学研究

• 批准号: 60550474
• 负责人: MORI Katsumi
• 金额: $ 1.22万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60550474/
• 关键词: Hot metal; Dephosphorization; Pretreatment of hot metal; Soda ash; Decarburization; 反応速度

In the pretreatment of hot metal by soda ash, the reaction between soda and carbon always proceeds as a side reaction and influences the progress of dephosphorization and desulfurization of hot metal. However, the corelation between these reactions has not been sufficiently understood from the viewpoint of reaction kinetics.In the present work, the effects of carbon and silica on the rate of dephosphorization of hot metal by soda ash were investigated by examining the change in the composition of both the metal and the gas evolved during a run. The results obtained are as follows:In the reaction between soda ash and Fe-C melt, soda ash was reduced partly to Na vapor and the gases evolved contained only CO.For Fe-P-C melts, the dephosphorization proceeded preferentially and the decarburization began after the metal phosphorus content decreased down to 0.05%. The increase in the flux amount from 5 g to 9 g resulted in the increased dephosphorization, but further increase in the flux amount to 15 g produced only the increase of the rate of decarburization.While, the gases evolved during the period of dephosphorization contained 4 to 6 % <CO_2> and about 50% CO, from which the partial pressure of oxygen was calculated to be <10^(-11)> atm.When silica was added to the flux, 40 to 60% of <CO_2> and several percent of CO were detected in the gases. This result showed that the reaction between soda ash and silica proceeded so fast and <CO_2> gas produced in the bulk of flux was not utilized for the dephosphorization and the decarburization of hot metal.

纯碱预处理铁水时，纯碱与碳的反应总是作为副反应进行，影响铁水脱磷、脱硫的进程。然而，从反应动力学的角度来看，这些反应之间的相互关系还没有被充分理解。在目前的工作中，通过检查运行过程中金属和气体的组成变化，研究了碳和二氧化硅对苏打灰铁水脱磷速率的影响。结果表明：在纯碱与Fe-C熔体反应中，纯碱部分被还原为Na蒸气，放出的气体仅含有CO。对于Fe-P-C熔体，脱磷优先进行，当金属磷含量降至0.05%时开始脱碳。熔剂用量从5 g增加到9 g导致脱磷率增加，但熔剂用量进一步增加到15 g时，仅产生脱碳率的增加。而脱磷期间放出的气体含有4%～6%<CO_2>和约50%CO，由此计算出氧分压为<10^(-11)>atm。 在气体中检测到40%至60%的<CO_2>和百分之几的CO。结果表明，纯碱和二氧化硅之间的反应进行得很快，熔剂本体中产生的<CO_2>气体没有被用于铁水的脱磷和脱碳。