粉煤灰回收氧化铝工艺研究现状及进展

Research status and progress of alumina recovery from fly ash

综合利用高铝粉煤灰中的高价值元素,特别是成分占比较高的铝元素,不仅可以降低我国对国外优质铝土矿的依赖度,而且可以缓解我国燃煤电厂的固废处理压力。阐述了粉煤灰的一些基本性质以及从粉煤灰中提取氧化铝的技术进展,对粉煤灰提取氧化铝的碱法工艺、酸法工艺、酸碱联合及碳热还原法、生物浸出法、气相提取法等工艺进行了介绍,并指出了不同工艺的优缺点,最后提出了未来从粉煤灰中提取氧化铝技术的发展方向。

Comprehensive utilization of high-value elements in high alumina fly ash,especially the high content of aluminum,can not only reduce the dependence of China on foreign high-quality bauxite,but also alleviate the pressure of solid waste treatment in coal-fired power plants in China.Some basic properties of fly ash and the technological progress of extracting alumina from fly ash are described.The processes of extracting alumina from fly ash,such as alkali process,acid process,acid-base combination and carbonthermal reduction process,bioleaching process and gas phase extraction process,are introduced.The advantages and disadvantages of different processes are pointed out.Finally,the development direction of alumina extraction from fly ash in the future is proposed.