关键词: 粉煤灰, 氧化铝, 铝土矿, 提取技术

Abstract: Coal fly ash（CFA），an industrial by-product，is derived from coal combustion in thermal power plants.It is one of the most complex and abundant of anthropogenic materials，and its improper disposal had resulted in a waste of recoverable resources.As coal fly ash is rich in alumina，it can be used for a potential substitute for bauxite.The necessity of extracting alumina from fly ash from two aspects，such as the preparation and utilization of China′s CFAs and the shortage of bauxite resources，was discussed，respectively.Then various techniques and the latest technology research advances in extracting alumina from fly ash were reviewed.Finally，the shortcomings of fly ash recycling and directions for research and development were forecasted.

Key words: fly ash, alumina, bauxite, extraction technique