高铝粉煤灰提取氧化铝的研究进展

Research Progress of Extracting Alumina from High-aluminum Fly Ash

高铝粉煤灰是近年来在我国北方地区发现的一种新的粉煤灰类型,其主要特点是粉煤灰中氧化铝的含量高达40%左右。高铝粉煤灰作为一种区别于铝土矿的非传统氧化铝资源,其利用方式一直备受关注。高铝粉煤灰提取氧化铝既能有效降低粉煤灰环境污染,又能缓解我国铝土矿资源短缺问题。实现了粉煤灰的高附加值利用,同时符合国家循环经济的发展要求,相关研究近年来已成为一个研究热点。本文对国内某高铝粉煤灰化学组成、物相组成、粒度组成、形貌等基本特性进行了分析。在此基础上对国内外粉煤灰提铝技术,包括石灰石烧结法、碱石灰烧结法、酸溶法、酸碱联合法等从研究现状、反应原理和技术优缺点等几个方面进行了分析和比较。指出了制约各种方法工业化发展的关键因素。最后结合近年来的研究进展,探讨了今后应解决的关键问题和主要研究方向。

High-aluminum fly ash is a new type fly ash found in northern region of China with the characteristics that the content of alumina reaches about 40%. As a kind of non-traditional alumina resources, its utilization pattern is always concerned. Extracting aluminum from high-aluminum fly ash can not only reduce environmental pollution, but also alleviate the problem of bauxite resource shortage, realizing high-valued utilization of fly ash, meeting the re- quirement of circulation economy development and becoming a research hotspot. Some basic characteristics such as chemical components, phase composition, size composition and morphology was analyzed in this paper. On the basis of the analysis, some extracting aluminum technologies including limestone sintering, soda-lime sintering, acid leac- hing and acid alkali combination were analyzed and contrasted in the aspects of research status, reaction principle and advantages and disadvantages of technology ,pointing out the key factors which restricts industrialization devel- opment. Moreover, according to the research progress, the further orientation of fly ash utilization was discussed.