摘要
The magnetization reduction of hematite using biomass waste can effectively utilize waste and reduce CO_(2) emission to achieve the goals of carbon peaking and carbon neutrality.The effects of temperatures on suspension magnetization roasting of hematite using biomass waste for evolved gases have been investigated using TG-FTIR,Py-GC/MS and gas composition analyzer.The mixture reduction process is divided into four stages.In the temperature range of 200-450℃ for mixture,the release of CO_(2),acids,and ketones is dominated in gases products.The yield and concentration of small molecules reducing gases increase when the temperature increases from 450 to 900℃.At 700℃,the volume concentrations of CO,H_(2) and CH_(4) peak at 8.91%,8.90% and 4.91%,respectively.During the suspension magnetization roasting process,an optimal iron concentrate with an iron grade of 70.86%,a recovery of 98.66% and a magnetic conversion of 45.70% is obtained at 700℃.Therefore,the magnetization reduction could react greatly in the temperature range of 600 to 700℃ owing to the suitable reducing gases.This study shows a detail gaseous evolution of roasting temperature and provides a new insight for studying the reduction process of hematite using biomass waste.
为了实现生物质废料的清洁利用,本文以生物质废料为焙烧还原剂,进行了不同温度下的赤铁矿焙烧试验。利用了TG-FTIR,Py-GC/MS和气体成分分析等检测方法,表征了磁化焙烧过程中不同温度下的气体演变行为。热重结果表明该焙烧过程主要分为脱除自由水阶段、生物质挥发分逸出阶段、磁化还原阶段以及过还原阶段。当焙烧温度在200-450℃时,主要的逸出产物为CO_(2)、酸类和酮类;随着焙烧温度升高至900℃时,CO、H_(2)和CH_(4)小分子还原气体浓度不断增加至13.09%,14.38%和10.03%。在最佳焙烧温度700℃时,可得到铁精矿品位70.86%、回收率98.66%、磁性转化率45.70%的焙烧产品,此时CO、H_(2)和CH_(4)的气体浓度分别为8.91%、8.90%和4.91%。本文确定了最佳焙烧温度为700℃,揭示了低温下逸出气体主要以CO_(2)及有机气体分子形式存在,表明了焙烧温度的升高利于小分子还原性气体CO、CH4和H2的生成,为生物质废料还原赤铁矿的清洁利用提供了新的思路。
作者
CAO Yue
SUN Yong-sheng
HAN Yue-xin
GAO Peng
LI Yan-jun
曹越;孙永升;韩跃新;高鹏;李艳军(School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,China;National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources,Shenyang 110819,China)
基金
Project(52022019)supported by the National Natural Science Foundation of China。
