不锈钢粉尘碳热还原渣高效粉化分离  

Efficient pulverization and separation of carbothermal reduction slag from stainless steel dust

作　　者：刘培军 储满生 柳政根 闫瑞军[1,2,3] 唐珏 LIU Peijun;CHU Mansheng;LIU Zhenggen;YAN Ruijun;TANG Jue(School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China;Institute for Frontier Technologies of Low-carbon Steelmaking,Northeastern University,Shenyang 110819,Liaoning,China;Liaoning Low-carbon Steelmaking Technology Engineering Research Center,Shenyang 110819,Liaoning,China;State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,Liaoning,China;Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education),Shenyang 110819,Liaoning,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110819 [2]东北大学低碳钢铁前沿技术研究院,辽宁沈阳110819 [3]辽宁省低碳钢铁前沿技术工程研究中心,辽宁沈阳110819 [4]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819 [5]低碳钢铁前沿技术教育部工程研究中心,辽宁沈阳110819

出　　处：《钢铁》2023年第12期156-164,共9页Iron and Steel

基　　金：国家自然科学基金资助项目(51974077)。

摘　　要：不锈钢粉尘是钢铁冶炼过程产生的典型二次固废,其含有大量的有价金属铁、铬和镍的氧化物,具有较高的回收利用价值。碳热还原法是一种高效冶炼金属矿物的火法工艺,使用碳热还原法处理不锈钢粉尘过程中,还原渣发生的粉化反应及冷却后的粉化效果会影响还原渣体系的理化性能,影响还原产物渣和金属的分离效果。通过高温试验研究了粉化控制过程工艺参数保温温度、保温时间和降温速率对还原渣粉化效果的影响。试验结果表明,不锈钢粉尘碳热还原-粉化控制后获得的还原渣自粉化率及自粉化渣的质量分数随着保温温度的升高呈现先增加后降低的趋势;还原渣自粉化率及自粉化渣的质量分数随着保温时间的增加呈现逐渐增长的趋势;还原渣自粉化率及自粉化渣的质量分数随着降温速率的降低呈现逐渐增长的趋势。在还原温度为1 450℃、升温速率为10℃/min、还原时间为20 min、碳氧比为0.8、控制保温温度为1 100℃、保温时间为15 min、降温速率为15℃/min的条件下,还原渣的自粉化率达到95.26%,自粉化渣的质量分数达到91.36%。在不锈钢粉尘碳热还原的过程中,还原渣中Ca2SiO4的生成反应极易进行,在不锈钢粉尘粉化控制过程中,温度低于1 100℃时,还原渣中基本没有Ca2SiO4生成,温度高于1 100℃时,Ca2SiO4的生成反应快速进行,促进了还原渣的自粉化率和自粉化渣的质量分数,在保证充足的还原条件下,有效提升还原产物渣和金属的分离效果,获得了高金属回收率和高品质合金颗粒。Stainless steel dust is a typical secondary solid waste generated during the steel smelting process,which contains a large amount of valuable metal oxides such as Fe,Cr,and Ni,and has high recycling value.Carbothermal reduction method is an efficient pyrometallurgical process for smelting metal minerals.During the process of treating stainless steel dust using carbothermal reduction method,the pulverization reaction of the reduced slag and the pulverization effect after cooling will affect the physical and chemical properties of the reduced slag system,and affect the separation effect of the reduced product slag and metal.The effect of the process parameters,such as the holding temperature,holding time and cooling rate,on the pulverization effect of the reduced slag has been investigated by high temperature experiments.Experimental results show that the rate of self-pulverization and the content of self-pulverization slag obtained after carbothermal reduction-powdering of stainless steel dust increases initially and then decreases as the holding temperature increases;the rate of self-pulverization and the content of self-pulverization cinders increases gradually with the holding time;the self-pulverization rate and the self-pulverization slag content of the reduced slag gradually increase as the cooling rate decreases.Under the conditions of a reduction temperature of 1450℃,a heating rate of 10℃/min,a reduction time of 20 min,a carbon oxygen ratio of 0.8,a holding temperature of 1100℃,a holding time of 15 min,and a cooling rate of 15℃/min,the self-pulverization rate of reduction slag reaches 95.26%,and the content of self-pulverization slag reaches 91.36%.The Ca2SiO4 formation reaction in the reduced slag is very easy to carry out in the process of carbothermal reduction of stainless steel dust.In the process of stainless steel dust pulverization control,when the temperature is lower than 1100℃,there is basically no Ca2SiO4 formation in the reduction slag.When the temperature is higher than 1100℃,the

关 键 词：不锈钢粉尘 碳热还原 自粉化渣 固废回收利用 硅酸二钙 

分 类 号：X757[环境科学与工程—环境工程]