低灰煤是开发煤炭应用新领域的前提。对于一些适宜的煤种，利用净化能力强、分选效率高的旋流微泡浮选柱可以分选出灰分小于２％的低灰煤。探讨了低灰煤制备原料的选择方法和浮选柱制备低灰煤的分选工艺。 Low-ash coal is a prerequisite for developing new areas of coal applications. For some suitable types of coal, low-ash coal with ash content less than 2% can be sorted by swirling microbubble flotation column with high purification capacity and high sorting efficiency. The selection method of raw materials for preparing low-ash coal and the sorting process for preparing low-ash coal by flotation column are discussed.