摘要
为提高钢渣的资源综合利用并减少钢铁冶炼过程排放的CO_(2),采用浸出-高温烧结工艺对转炉钢渣进行改质。通过浸出过程,将含钙组分制备成钙基吸附材料,同时富集回收浸出渣含铁组分。考察了浸出参数对钙基吸附剂组成的影响,为探究钢渣颗粒中钙的浸出过程,采用收缩核模型对钢渣颗粒在弱酸性溶液中的浸出速率进行了分析。研究了浸出渣经高温改质物相结构变化,并分析铁元素转变规律。此外,通过使用XRD和SEM分析钙基材料的物相结构。最后,测算钙基材料的吸附性能。结果表明,浸出温度和醋酸浓度对钙基材料中CaO含量影响较大。在较大的粒径下,最佳的浸出参数为酸浓度1 mol/L、固液比1∶10、浸出温度70℃以及时间2 h,此条件下CaO含量最高达86.3%。动力学结果表明,在搅拌条件下,钙浸出过程由内扩散控制。在40~70℃内,钙浸出过程的速率控制步骤未发生变化,仍由内扩散控制。制备的钙基材料CaO纯度较高,且CO_(2)吸附量随着CaO含量增加而增大,在常压条件下最高可达60.6 mg/g。对浸出渣高温改质后,Ca_(2)Fe_(2)O_(5)相转变成了尖晶石相(Fe_(3)O_(4)、MgFe_(2)O_(4)),钙铁元素得到了很好的分离和富集回收。
To improve the comprehensive utilization of steel slag resources and reduce the CO_(2)emission in the process of iron and steel smelting,the leaching and high-temperature sintering process was used to modify the steel slag of converter.Through the leaching process,the calcium-containing components were prepared into calcium-based adsorption materials,and the iron-containing components of the leaching residue were enriched and recovered.The effect of leaching parameters on the composition of calcium-based adsorbent was investigated.To investigate the leaching process of calcium in steel slag particles,the leaching rate of steel slag particles in a weakly acidic solution was analyzed by using a shrinkage core model.The phase structure change of leaching residue modified by high temperature was studied,and the transformation rule of iron elements was analyzed.In addition,the phase structure of the calcium-based material was checked by XRD and SEM observations.Finally,the adsorption properties of the calcium-based materials were measured.The results show that the leaching temperature and acetic acid concentration have a great influence on the CaO content in the calcium-based materials.Under larger particle size,the optimal leaching parameters were acid concentration 1 mol/L,solid-liquid ratio 1∶10,leaching temperature 70℃,and leaching time 2 h.Under these conditions,the CaO content reached 86.3%.Under stirring conditions,the calcium leaching process is controlled by internal diffusion.In the range of 40—70℃,the rate control steps of the calcium leaching process did not change and were still controlled by internal diffusion.The CaO purity of the prepared calcium-based material is higher,and the adsorption capacity of CO_(2) increases with the increase of CaO content,which can reach up to 60.6 mg/g under atmospheric pressure.After the leaching residue was modified at high temperature,the Ca_(2)Fe_(2)O_(5)phase was transformed into the spinel phase(Fe_(3)O_(4),MgFe_(2)O_(4)),and calcium and iron elements were separated,enriched,and recovered well.
作者
成洁
杨志彬
朱祚峤
李智翔
常江
鞠晓婷
CHENG Jie;YANG Zhibin;ZHU Zuoqiao;LI Zhixiang;CHANG Jiang;JU Xiaoting(School of Metallurgy and Material Engineering,Zhangjiagang Campus,Jiangsu University of Science and Technology,Zhangjiagang 215600,China;Research Institute of Environmental Protection and Resources,Jiangsu(Shagang)Iron and Steel Research Institute,Zhangjiagang 215625,China)
出处
《有色金属工程》
CAS
北大核心
2024年第7期78-89,共12页
Nonferrous Metals Engineering
基金
国家自然科学基金资助项目(51304082)
江苏省自然科学基金项目(BK20130462)
冶金减排与资源综合利用教育部重点实验室开放基金(JKF21-01)。
关键词
转炉钢渣
CO_(2)减排
钙基吸附剂
金属元素回收
酸浸动力学
steel slag
CO_(2)emission reduction
calcium-based adsorbent
metal element recovery
acid leaching kinetics
