Abstract: The small inclusions is hard to removal by buoyancy during continuous casting. The method of using highspeed liquid steel to break gas into fine gas bubbles to removal small inclusions in liquid steel is an alternative measure. Fine gas bubbles formation in the ladle and the existing problems was reviewed，and the formation process of small bubbles in the ladle shroud was analyed by the chemical industry’s relevant research results on bubble breakup and coalescence in turbulent liquid. It was found that the constriction of fine gas bubbles formation is the short residence time of initial bubble in the high turbulent region. At the same time, the method of controlling fine gas bubbles in the ladle shroud has been prospected.

Key words: ladle shroud, fine gas bubbles, breakup, coalescence