粉煤灰回收氧化铝工艺研究进展

Research progress of alumina recovery technology from coal fly ash

粉煤灰是火力发电行业煤炭燃烧工业的副产品,是中国固体废弃物污染的主要来源。粉煤灰富含氧化铝,所以又是潜在的铝土矿的替代品。从粉煤灰中提取氧化铝不仅可以减少粉煤灰对环境的污染,而且能缓解中国铝土资源短缺的问题。对粉煤灰性质、危害、粉煤灰利用现状以及中国铝土资源现状做了分析,论证了粉煤灰提取氧化铝的必要性;详细介绍了石灰石烧结法、硫酸铵烧结法和一步酸溶法的工艺路线、建设生产情况及各工艺的优缺点,为粉煤灰提取氧化铝的发展提出建议,并呼吁加强粉煤灰提取铝工艺方法的研究力度。

Coal fly ash,an industrial byproduct,is from coal combustion in fuel electric plant.It is the main source of solid waste.Meanwhile, it is a potential substitute for monohydrallite due to its high aluminum content.Extracting alumina from coal fly ash can reduce the pollution of the environmental caused by coal fly ash and relieve the shortage of monohydrallite resources.The necessity of extracting alumina from coal fly ash has been proven by summarizing the properties and danger of coal fly ash, status of bauxite resources, and utilization status of coal fly ash.Some extraction methods including limestone sintering method,ammonium sulfate sintering method,one-step acid digestion method as well as the merits and defects of their technology process and production condition were discussed specifically.The prospects for recovery of alumina from coal fly ash and correlated recommendations were also presented for the further study on comprehensive utilization of coal fly ash.