| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for treating a selenium-containing waste water capable of easily achieving high selenium removing ratio while effectively suppressing the generation of sludge even if the selenium-containing waste water contains metal salts. SOLUTION: When a selenium removing treatment in which at least one kind ferrous metal selected from a group consisting of Fe, Mn, Ni and Cu is brought into contact with the waste water containing salts and a dissolved selenium and a separated precipitate is subjected to solid-liquid separation to remove the dissolved selenium is performed, before the selenium removing treatment, a pH value of the waste water is adjusted by adding alkali in the waste water and a pretreatment subjecting the separated precipitate to the solid-liquid separation is performed, and also the selenium removing treatment is performed under the condition whose pH value is not higher than that at the pretreatment.</p> |
