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
刘培军 1储满生 2柳政根 1闫瑞军 1唐珏1
作者信息
- 1. 东北大学冶金学院,辽宁沈阳 110819;东北大学低碳钢铁前沿技术研究院,辽宁沈阳 110819;辽宁省低碳钢铁前沿技术工程研究中心,辽宁沈阳 110819
- 2. 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;低碳钢铁前沿技术教育部工程研究中心,辽宁沈阳 110819
- 折叠
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.
Abstract
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 pul-verization 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 hold-ing 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-pulveriza-tion cinders increases gradually with the holding time;the self-pulverization rate and the self-pulverization slag con-tent of the reduced slag gradually increase as the cooling rate decreases.Under the conditions of a reduction temper-ature of 1 450 ℃,a heating rate of 10 ℃/min,a reduction time of 20 min,a carbon oxygen ratio of 0.8,a holding temperature of 1 100 ℃,a holding time of 15 min,and a cooling rate of 15 ℃/min,the self-pulverization rate of re-duction slag reaches 95.26％,and the content of self-pulverization slag reaches 91.36％.The Ca2SiO4 formation re-action 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 1 100 ℃,there is basi-cally no Ca2SiO4 formation in the reduction slag.When the temperature is higher than 1 100 ℃,the formation reac-tion of Ca2SiO4 is fast,which promotes the self-pulverization rate of the reduction slag and the content of self-pul-verization slag.Under sufficient reduction conditions,the separation effect of reduced product slag and metal is ef-fectively improved,resulting in high metal recovery ratio and high-quality alloy particles.
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Key words
stainless steel dust/carbothermal reduction/self-pulverization slag/solid waste recycling/Ca2SiO4引用本文复制引用
基金项目
国家自然科学基金资助项目(51974077)
出版年
2023
NETL
NSTL
维普
万方数据