| 摘要 |
PURPOSE:To effectively execute the decomposition and removal of the low molecular weight sbstance and to reduce the pollution index, by installing the passage for returning a part of treated water from the photo-oxidization apparatus to the biological treating apparatus. CONSTITUTION:The return passage R is installed so as to connect the downstream side of the photo-oxidization apparatus 4 with the upstream side of the biological treating apparatus 2 in order to return and treat once again a part of the treated water delivered from the photo-oxidization apparatus 4; hereby, the residual low molecular weight substance to be treated is decomposed and removed. The return passage R1 for returning ozone as shown by the broken line is installed on the upstream side of the biological treating apparatus 2 on purpose to return the ozone from the photo-oxidization apparatus 4; hereby, the excessive ozonized air of the photo-oxidization apparatus 4 is supplied to the waste water being introduced into the biological treating apparatus 2 in order to effectively utilize the excessive ozonized air and to reduce the amount of oxygen to be supplied to the biological treating apparatus 2 for breeding the microorganisms. |
