The economic-technical indexes and application of a 30 t AOD unit at Pugang
40 t AOD units at Taiyuan Steel and a 120 t AOD unit at Shanghai Nol Steel in China are summarized. The development of AOD refining technology such as decarburization
desulphurization
replacing Ar with N
2
and top lance technology is presented and the technical issues including to perfect gas supply model for AOD refining and service life of furnace lining are discussed in this article.