Abstract
In this study, actual river water, that was pretreated by coagulation sedimentation, was treated in a fixed bed mini-column of biological activated carbon (BAC) or sand for a very long term about 1,800days, and the changes of effects to remove organic compounds by biodegradations and adsorption were investigated. In sand column which has only biodegradation effect by biofilm, 34% of organic compounds as TOC could be removed after one or two months of lag time. Biodegradation of organic compounds which had adsorbed once in pores brought about the extension of adsorption ability of BAC, and pore volume was recovered. Adsorption ability decreased with pore volume decrease by adsorption of organic compounds which were hardly degradable, and TOC removal ratio of BAC decreased gradually and became as same as that for sand after a long time.
