| 摘要 |
PROBLEM TO BE SOLVED: To provide an industrially usable and economically excellent waste water treatment method that can more easily and efficiently treat cyanide-containing waste water into a more safe state and can further reduce cyanide components in treated water than conventional methods by developing a cyanide-containing waste water treatment method in which a new chemical is more effectively used. ! SOLUTION: In a waste water treatment method where a ferrous salt, a nitrogen-containing compound, and a cuprous salt are added to cyanide-containing waste water to insolubilize and remove the cyanide components, the nitrogen-containing compound is an organic nitrogen-containing compound, and a process is provided which adds the ferrous salt prior to or concurrently with introduction of the cyanide-containing waste water into a settling tank to make the ferrous salt coexist in the waste water, introduces the waste water into the settling tank, and then, adds the organic nitrogen-containing compound and th |
