To provide a method for recovering a valuable metal, which lowers the chlorine content to 2 mass% or below but prevents the valuable metal from being eluted into a washing liquid by dechlorination-washing fly ash containing the valuable metal and chlorine under a specified pH condition prior to an operation for recovering the valuable metal.
The valuable metal recovery method comprises the steps of: dechlorination-washing fly ash containing the valuable metal and chlorine with a washing liquid with a pH of 10 to 12; mixing the dechlorinated fly ash, a zinc-containing raw material, a flux, and coal; drying the mixture; crushing the dried product; forming the crushed product into an agglomerated ore; and melt-reducing the agglomerated ore. Alternatively, the valuable metal recovery method comprises the steps of: recovering zinc as crude zinc oxide by melt-reduction of the agglomerated ore; further dechlorination-washing the recovered crude zinc oxide with a washing liquid with a pH of 10 to 12; and using the dechlorinated crude zinc oxide in zinc refining.
COPYRIGHT: (C)2007,JPO&INPIT
Takuji Yoshida
Tokuichi Hiroyuki
Shinji Noda
Sekiguchi Tomoo
Hiroshi Sato
JP2002018394A | ||||
JP10053820A | ||||
JP2003130318A | ||||
JP7268500A |
Muranaka