| 摘要 |
PURPOSE:To effectively lower the COD value of a waste liquid contg. chilated iron- components by putting this waste liquid under an alkaline condition to form hydroxide precipitate and subjecting the liquid after solid-liquid sepn. to a wet process oxidation treatment and biological treatment in the presence of an oxidation catalyst. CONSTITUTION:For example, the photographic waste liquid contg. the chilated iron- components at >=10 to <=5000mg/L is put into a reaction chamber and an aq. sodium hydroxide soln. is added to this liquid to adjust its pH to 9 to 14. The waste liquid is rested as it is for several days under stirring. As a result, the reddish brown precipitate is deposited as time passes by. The formed precipitate is flocculated by adding a high polymer flocculating agent and thereafter, the liquid contg. the generated precipitate is filtered by a filter machine. The resulted filtrate is diluted twice and is introduced into a wet process oxidation reaction column 1 packed with the catalyst contg. 1wt.% platinum. The air is supplied from a compressor 3 into this column in such a manner that the oxygen quantity twice the COD value of the diluting liquid is attained, by which the filtrate is subjected to the wet process oxidation treatment, then to the biological treatment. |
