Abstract
In drinking water treatment process including ozonation and biological activated carbon (BAC) filtration, the treatment capability of BAC filter was compared with that of biological filter with a carrier having no adsorption capacity, to clarify the effect of adsorption and biodegradation activity on the mechanism in BAC filtration. Trihalomethane formation potential (THMFP) and E260 were highly removed by the combination of ozonation and BAC filtration. On the other hand, the biological filter had generally lower removal potentiality compared with BAC filter. However it appeared that higher removal potentiality close to that of BAC filter was achieved by the combination of ozonation and biological filter at high water temperature. Number of bacteria on BAC was little different from that on the medium for biological filter.
The removal potentiality of THMFP and E260 in the combination of ozonation and BAC filtration was little different from that in BAC filtration without ozonation. However the adsorption load for BAC was decreased by oxidation and improvement of biodegradability at preozonation.
