title: High-rate partial nitritation using porous poly(vinyl alcohol) sponge.
abstract: Poly(vinyl alcohol) (PVA) has been utilized as a support material for the immobilization of nitrifying bacteria without the comprehensive survey of partial nitritation. In the present study, the activities of nitrifiers and the maximum nitrogen conversion rate of partial nitritation with PVA sponge-cubes were specified according to different conditions. The selective enrichment of ammonia-oxidizing bacteria (AOB) on PVA sponge-cubes was achieved by the competition between AOB and nitrite-oxidizing bacteria for dissolved oxygen. The efficiency of ammonia oxidation was proportional to the concentration of HCO3 (-) with the molar ratio of HCO3 (-)-C/NH4 (+)-N = 1.91 and a half of the ratio was applied to the further experiments to ensure stable partial nitritation. The maximum nitrogen conversion rate of partial nitritation was dependent on the volume, not the size of sponge-cubes. The partial nitritation showed the superior rate performance of 3.09 kg N/m(3) day with the packing ratio of 32 % of 5 × 5 × 5 mm(3) PVA sponge-cubes.
authors.affiliation: Center for Water Resource Cycle Research, Korea Institute of Science and Technology, 39-1 Hawolgok-Dong, Seongbuk-Gu, Seoul, 136-791, Republic of Korea.
authors.forename: Hyokwan
authors.initials: H
authors.lastname: Bae
authors.forename: Heejeong
authors.initials: H
authors.lastname: Yang
authors.forename: Yun-Chul
authors.initials: YC
authors.lastname: Chung
authors.forename: Young Je
authors.initials: YJ
authors.lastname: Yoo
authors.forename: Seockheon
authors.initials: S
authors.lastname: Lee
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D058465:Nitrification / Q000502:physiology*; D010084:Oxidation-Reduction; D011142:Polyvinyl Alcohol / Q000737:chemistry*
chemical_list: D000641:Ammonia; D011142:Polyvinyl Alcohol