公开(公告)号：US06511316B2

公开(公告)日：2003-01-28

申请号：US09892695

申请日：2001-06-28

申请人： Takao Harada ,  Masahiko Tetsumoto ,  Hidetoshi Tanaka

发明人： Takao Harada ,  Masahiko Tetsumoto ,  Hidetoshi Tanaka

IPC分类号： F27B916

CPC分类号： F27D25/001 ,  C21B13/10 ,  F27B9/16 ,  F27B2009/126 ,  F27B2009/3607 ,  F27B2009/384 ,  F27D3/08 ,  F27D2003/0038 ,  F27D2009/0089

摘要： To provide an operating method of a rotary hearth furnace for producing reduced iron in which a stuck substance stuck on the hearth surface is removed from the hearth surface to thereby prevent or reduce the wear of the knife edge of a screw of a discharge device, enabling continuous operation for a long period and capable of achieving high availability factor. The hearth surface is quenched by spraying or the like to generate cracks in the stuck substance on the hearth, and the stuck substance is scraped to thereby remove it from the hearth.