摘要
煤矸石或粉煤灰与赤泥协同钠化还原焙烧均可实现其所含铁、铝、硅等元素的形态转化,使其易于分离回收;但对于它们分别与赤泥协同钠化还原焙烧反应差异性及机制的研究目前尚未见报道。采用X射线衍射分析方法,分别考察了煤矸石-赤泥、粉煤灰-赤泥体系钠化还原焙烧过程中,气氛类型、钠助剂添加量、焙烧温度、焙烧时间对还原焙烧产物物相组成的影响规律,并对两个反应体系中铁磁化效果及铝硅活化效果的差异性进行分析。结果表明:在钠化还原焙烧过程中,煤矸石-赤泥、粉煤灰-赤泥体系均可同步实现含铁物相的磁化和铝硅物相的活化,且随着钠助剂添加量、焙烧温度、焙烧时间的变化,含铁物相和铝硅物相呈现规律性变化;在相同铁磁化和铝硅活化效果前提下,煤矸石-赤泥体系所需钠助剂添加量、焙烧温度和焙烧时间均略低于粉煤灰-赤泥体系,这主要与煤矸石、粉煤灰中所含还原性物质和铝硅矿物的赋存形态、含量及微观结构有关。研究将为煤矸石、粉煤灰等煤基固废与赤泥协同钠化还原焙烧回收有价元素的原料筛选提供理论指导。
Coal gangue or fly ash and red mud synergistic sodium reduction roasting can realize the form transformation of iron,aluminum,silicon and other elements contained in it,making it easy to separate and recycle.However,a research on the difference of sodium reduction roasting reaction between coal gangue-red mud system and coal fly ash-red mud system has not been reported.In this paper,the influence of atmosphere type,sodium additive amount,roasting temperature and roasting time on the phase composition of the reductive roasted product from coal gangue-red mud and coal fly ash-red mud system was investigated by X-ray diffraction analysis method.In addition,the difference of iron magnetization and aluminum-silicon activation between coal gangue-red mud and coal fly ash-red mud system was analyzed.The results showed that coal gangue-red mud and coal fly ash-red mud systems can simultaneously realize the magnetization of iron-containing phase and the activation of aluminum-silicon phase during the sodium reduction roasting process.The iron-containing phase and the aluminum-silicon phase showed regular changes with the change of sodium additive amount,roasting temperature and roasting time.The sodium additive amount,roasting temperature and roasting time for the coal gangue-red mud system were slightly lower than those for the coal fly ash-red mud system with the same degree of iron magnetization and aluminum-silicon activation.It is mainly related to the occurrence,content and microstructure of reducing substances and aluminosilicate minerals in coal gangue or coal fly ash.This study will provide a theoretical guidance for the feed selecting during the recovery of valuable elements by sodium reduction roasting of coal-based solid wastes(such as coal gangue,coal fly ash)and red mud.
作者
郭志强
燕可洲
张吉元
柳丹丹
高阳艳
郭彦霞
GUO Zhiqiang;YAN Kezhou;ZHANG Jiyuan;LIU Dandan;GAO Yangyan;GUO Yanxia(Institute of Resources and Environmental Engineering,State Key Laboratory of Environmental Protection and Efficient Utilization of Coal Wastes,Shanxi University,Taiyuan 030006,Shanxi,China;School of Environmental Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,Shanxi,China;School of Environment and Resources,Shanxi University,Taiyuan 030006,Shanxi,China)
出处
《化工学报》
EI
CAS
CSCD
北大核心
2022年第5期2194-2205,共12页
CIESC Journal
基金
国家自然科学基金青年基金项目(22008144)
山西省重点研发计划项目(201903D311006)。
关键词
烧结
活化
还原
废物处理
sintering
activation
reduction
waste treatment
