碱烧结法回收二次铝灰中氧化铝
Study on alumina recovery in secondary aluminum ash by alkali sintering method
伍永福 1鲍高战 1王日昕 2刘中兴 1练以诚 3刘玉宝4
作者信息
- 1. 内蒙古科技大学 能源与环境学院,内蒙古 包头 014010;轻稀土清洁提取与应用内蒙古自治区工程研究中心,内蒙古 包头 014010
- 2. 江西省科学院应用物理研究所,江西 南昌 330029
- 3. 中铝环保节能集团有限公司,北京 102209
- 4. 包头稀土研究院白云鄂博稀土资源研究与综合利用国家重点实验室,内蒙古 包头 014010
- 折叠
摘要
二次铝灰中蕴含大量的氧化铝、铝和氮化铝等,还有部分氟化物和氯化物盐类,属于危险废弃物.目前常用的铝回收技术有酸浸法和碱浸法,均存在工艺条件苛刻、回收率低、能耗高、物耗大和产品附加值较低等问题.本研究采用碱烧结法从二次铝灰中回收氧化铝,考察烧结温度对氮化铝转化率的影响,碱铝比、烧结时间和成型方式对氧化铝回收率的影响,得到以下主要结论:在烧结温度1 423 K、烧结时间40 min、碱铝比1.1、干压成型的试验条件下,氧化铝溶出率最大为94.23%;通过对二次铝灰铝酸钠熟料浸出渣成分以及物相进行分析,得到二次铝灰经过碱烧结法焙烧后熟料主要成分为Al2O3 和Na2O,分别占到49.70%和28.06%,熟料标准浸出后残渣主要成分为CaO、Al2O3 和MgO,含量分别为25.46%、20.27%和15.80%;二次铝灰中AlN分解率较高,可达到95%以上,最终浸出渣中氟离子浸出毒性在30 mg/L以下.综上所述,本文采用碱烧结法资源化利用二次铝灰,实现了二次铝灰脱氮固氟的无害化处置,具有环境友好、资源利用率高的优势,为后续大规模工业化推广奠定了理论基础.
Abstract
Secondary aluminum ash contains a large amount of alumina,aluminum and aluminum nitride,as well as some fluorides and chloride salts,which are hazardous wastes.At present,the commonly used aluminum recovery technologies,acid leaching method and alkali leaching method,have the problems of harsh process conditions,low recovery rate,high energy consumption,large material consumption and low added value of products.In this study,alkali sintering method was used to recover alumina from secondary aluminum ash.The effects of sintering temperature on aluminum nitride conversion,alkali aluminum ratio,sintering time and forming method on alumina recovery were investigated,and the main conclusions were obtained as follows.Under the experimental conditions of sintering temperature 1 423 K,sintering time 40 min,alkali to aluminum ratio 1.1 and dry pressing,the maximum dissolution rate of alumina is 94.23%.Through the analysis of the composition and phase of the leaching residue of sodium aluminate clinker of secondary aluminum ash,the main components of the clinker after calcination by alkali sintering method are Al2O3 and Na2O,accounting for 49.70%and 28.06%respectively,and the main components of the residue after standard leaching of clinker are CaO,Al2O3 and MgO.The contents were 25.46%,20.27%and 15.80%,respectively;The decomposition rate of AlN in secondary aluminum ash is higher,which can reach more than 95%,and the leaching toxicity of resource products is below 30 mg/L.In summary,this paper uses alkali sintering method for resource utilization of secondary aluminum ash,and realizes harmless treatment of secondary aluminum ash for nitrogen removal and fluorine fixation,which has the advantage of high utilization rate of environmentally friendly resources,and lays a theoretical foundation for subsequent large-scale industrialization.
关键词
二次铝灰/脱氮/固氟/铝回收/碱烧结法/无害化处置/浸出毒性/资源化利用Key words
secondary aluminum ash/denitrogenation/fluorine retention/aluminum recovery/alkali sintering method/harmless disposal/leaching toxicity/resource utilization引用本文复制引用
基金项目
国家自然科学基金(51964039)
内蒙古自然基金(2022LHMS05004)
内蒙古自然基金(2021GG0103)
白云鄂博稀土资源研究与综合利用国家重点实验室开放基金(2021H2275)
高校基本科研业务费项目(2024RCTD008)
内蒙古自治区教育科学研究"十四五"规划课题(NGJGH2022365)
出版年
2024
NETL
NSTL
万方数据