| 摘要 |
PROBLEM TO BE SOLVED: To provide a treatment method, in treating wastewater of sulfurization step of nickel oxide ore wet-type smelting method, in which the used amount of highly alkaline neutralizer of high cost can be suppressed and an efficient neutralization treatment can be done. ! SOLUTION: The treatment method is a neutralization treatment method for neutralization removing metal ions that resided in the barren solution generated from a treatment step for forming sulfide of nickel and cobalt by blowing hydrogen sulfide into sulfuric acid aqueous solution comprising nickel and cobalt, and impurity metal element at least comprising any one or more of iron, magnesium and manganese, and comprises a first neutralization treatment step S11 for carrying out a neutralization treatment to the barren solution with a pH 5.0 to 6.0 range as end point by using calcium carbonate slurry as a first neutralizer, and a second neutralization treatment step S12 for subjecting the solution obtained in the first neutrali |
