生物污泥还原钢铁厂含锌粉尘规律  

Law of zinc-bearing dust from iron and steel plant reduced by biological sludge

作　　者：魏汝飞 张飞虎 孟东祥 龙红明 李家新 WEI Rufei;ZHANG Feihu;MENG Dongxiang;LONG Hongming;LI Jiaxin(School of Metallurgical Engineering,Anhui University of Technology,Maanshan 243002,Anhui,China)

机构地区：[1]安徽工业大学冶金工程学院,安徽马鞍山243002

出　　处：《钢铁》2023年第6期134-142,共9页Iron and Steel

基　　金：安徽省自然科学基金资助项目(2208085ME121,2208085J19);国家重点研发计划重点专项资助项目(2022YFC3901405)。

摘　　要：钢铁尘泥是钢铁冶炼过程中产生的主要固体废弃物之一,如果直接堆放或排放,必然会造成环境污染,且尘泥中的有价元素也没有得到有效利用,因此对其进行资源化利用已成为钢铁厂面临的严重问题。火法工艺在钢铁尘泥的处理工艺中应用最广泛,在火法处理工艺的基础上,提出利用生物污泥中的碳代替煤粉/焦粉作为还原剂对钢铁含锌粉尘进行还原处理的新思路。在模拟转底炉的条件下进行了高温还原试验,选取质量比、反应温度和反应时间3个因素为主要影响因素,研究了尘泥含碳团块中铁氧化物和锌氧化物的高温自还原规律。采用XRD、SEM、GC/MS和XRF等手段对反应前后团块矿物组成、微观形貌、元素分布和化学成分等方面进行深入分析。研究结果表明,尘泥含碳团块的金属化率和锌脱除率随着生物污泥所占质量比的增大和反应温度的升高而增大。随着反应时间的延长,尘泥含碳团块的金属化率和锌脱除率先增加,20 min后趋于稳定。当电炉灰和生物污泥的质量比为1∶0.69、反应温度为1300℃、反应时间为20 min时,尘泥含碳团块的金属化率可达98.48%,锌脱除率可达98.95%。这说明利用生物污泥还原钢铁含锌粉尘,可以实现有价元素锌的回收,还原后得到的金属化团块可返回到钢铁生产流程中,实现钢铁尘泥中铁元素的资源化利用。Dust and sludge is one of the main solid wastes produced in the process of iron and steel making.If it is directly stacked or discharged,it will inevitably cause environmental pollution,and the valuable elements in the dust and sludge have not been effectively utilized,so its resource utilization has become a serious problem faced by steel plants.Pyrometallurgy method is most widely used in the treatment process of the dust and sludge.Based on the pyrometallurgical treatment process,a new idea of using carbon from biological sludge instead of coal powder and coke powder as reducing agent to reduce zinc-bearing dust from iron and steel plant are put forward.The simulated high temperature reduction experiments were carried out under the conditions of rotary hearth furnace.Three factors,including mass ratio,reaction temperature and reaction time,were selected as the main influencing factors to study the high temperature self-reduction law of iron oxide and zinc oxide in carbon-bearing agglomerates made by dust and sludge(CADS).XRD,SEM,GC/MS and XRF were used to analyze the mineral composition,microstructure,element distribution and chemical composition of CADS before and after the reaction.The results show that the metallization rate and the zinc removal rate of CADS increases with the increase of the mass ratio of biological sludge and reaction temperature.With the extension of reaction time,the metallization rate and zinc removal rate of CADS increased first,and then to be stable after 20 min.When the mass ratio of electric furnace ash to biological sludge is 1∶0.69,the reaction temperature is 1300℃,and the reaction time is 20 min,the metallization rate of CADS can reach 98.48%,and the zinc removal rate of CADS can reach 98.95%.This shows that the recovery of valuable element zinc can be realized by using biological sludge to reduce zinc-bearing dust,and the metallized agglomerates obtained after reduction can be returned to the steel production process,to realize the resource utilization of iron element in du

关 键 词：含锌粉尘 生物污泥 自还原反应 金属化率 锌脱除率 资源化利用 

分 类 号：TF089[冶金工程—冶金物理化学]