Removal of Natural Organic Matter (NOM) using biological contactor with rope media and ultrafiltration membrane

This paper is concerned chiefly with the biological removal of natural organic matter (NOM) dissolved in water resources using biological contactor with rope media. The biological treatment represents one option for the removal of NOM from water resource. In this study, we proposed a process including biological contactor with rope media and membrane filtration for the removal of NOM from water resource. We installed three rope media contactors to pilot scale traditional water treatment consisting of preozonation. coagulation, and sedimentation. The average removal yields of dissolved organic carbon (DOC) in biological contactor from raw water and ozonation were 3% and 14%, respectively. The average removal yield of biological contactor from sedimentation tank was 32%, which was much higher than the former case. The heterotrophic plate counts (HPC) value obtained from biological contactor unit reached over 10000 CFU (colony forming unit)/mL, which was five times higher even than that of raw water. However, the HPC could be reduced to below 50 CFU/mL by simple ultra-filtration membrane.