title: Evaluation on factors influencing the heterotrophic growth on the soluble microbial products of autotrophs.
abstract: In this work, the heterotrophic growth on the microbial products of autotrophs and the effecting factors were evaluated with both experimental and modeling approaches. Fluorescence in situ hybridization (FISH) analysis illustrated that ammonia oxidizers (AOB), nitrite oxidizers (NOB), and heterotrophs accounted for about 65%, 20%, and 15% of the total bacteria, respectively. The mathematical evaluation of experimental data reported in literature indicated that heterotrophic growth in nitrifying biofilm (30-50%) and granules (30%) was significantly higher than that of nitrifying sludge (15%). It was found that low influent ammonium resulted in a lower availability of soluble microbial products (SMP) and a slower heterotrophic growth, but high ammonium (>150 mg N L(-1)) feeding would lead to purely AOB dominated sludge with high biomass-associated products contained effluent, although the absolute heterotrophic growth increased. Meanwhile, the total active biomass concentration increased gradually with the increasing solids retention time, whereas the factions of active AOB, NOB, and heterotrophs varied a lot at different solids retention times. This work could be useful for better understanding of the autotrophic wastewater treatment systems.
authors.affiliation: School of Earth and Space Sciences, University of Science & Technology of China, Hefei, China.
authors.forename: Bing-Jie
authors.initials: BJ
authors.lastname: Ni
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Zeng
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.forename: Wen-Ming
authors.initials: WM
authors.lastname: Xie
authors.forename: Juan
authors.initials: J
authors.lastname: Xu
authors.forename: Guo-Ping
authors.initials: GP
authors.lastname: Sheng
authors.forename: Yu-Jiao
authors.initials: YJ
authors.lastname: Sun
authors.forename: Han-Qing
authors.initials: HQ
authors.lastname: Yu
mesh_terms: D000641:Ammonia / Q000378:metabolism; D052818:Autotrophic Processes; D001419:Bacteria / Q000254:growth & development* / Q000378:metabolism; D018407:Bacterial Physiological Phenomena; D018441:Biofilms / Q000254:growth & development; D052836:Heterotrophic Processes; D008954:Models, Biological; D009573:Nitrites / Q000378:metabolism; D010084:Oxidation-Reduction; D000644:Quaternary Ammonium Compounds / Q000378:metabolism; D012722:Sewage / Q000382:microbiology
chemical_list: D009573:Nitrites; D000644:Quaternary Ammonium Compounds; D012722:Sewage; D000641:Ammonia