To provide a method of producing economically recyclable high concentration zinc cake of a zinc concentration of at least 40%, by efficiently separating zinc present in a waste galvanization solution from iron at low cost.
A zinc composition including at least 40% of zinc per dry weight is recovered by an air-oxidation process of adding an alkali into a waste galvanizing solution comprising a zinc ion and a ferric ion each at least in a predetermined concentration and further comprising heavy metal to maintain its pH in a range of 4.5 to 5.5, blowing air thereinto to oxidize the ferric ion to a ferrous ion, and subsequently precipitating the ferrous ion as ferrous hydroxide; a first solid-liquid separation process of adding a chelating agent into the treated solution obtained and subsequently carrying out solid-liquid separation; a pH adjustment process of adding an alkali to the separated solution obtained to control its pH between 8 and 11 to precipitate zinc hydroxide; a second solid-liquid separation process of subjecting the treated solution obtained to solid-liquid separation; and washing the solid matter obtained.
TOMITA YOHEI
TSUCHIYA HIROSHI
UDAGAWA SATORU
OTANI AKEMI
JFE KANKYO CORP
JPS62253738A | 1987-11-05 | |||
JPS61261446A | 1986-11-19 | |||
JP2010284593A | 2010-12-24 | |||
JP2000117270A | 2000-04-25 | |||
JP2012082458A | 2012-04-26 | |||
JP2011157568A | 2011-08-18 | |||
JP2002030352A | 2002-01-31 | |||
JP2004202488A | 2004-07-22 | |||
JP2008266774A | 2008-11-06 | |||
JPS62253738A | 1987-11-05 | |||
JPS61261446A | 1986-11-19 | |||
JP2010284593A | 2010-12-24 | |||
JP2000117270A | 2000-04-25 | |||
JP2012082458A | 2012-04-26 |