LI Zhi hua, ZHANG Ting, WU Jie, et al. Effects of Heterotrophic and Autotrophic Bacteria on the Stability of Aerobic Granular Sludge[J]. Journal of Civil and Environmental Engineering, 2010, 32(5): 76-81.
DOI:
LI Zhi hua, ZHANG Ting, WU Jie, et al. Effects of Heterotrophic and Autotrophic Bacteria on the Stability of Aerobic Granular Sludge[J]. Journal of Civil and Environmental Engineering, 2010, 32(5): 76-81. DOI: 10.11835/j.issn.1674-4764.2010.05.014.
Effects of Heterotrophic and Autotrophic Bacteria on the Stability of Aerobic Granular Sludge
The characteristics of granules of heterotrophic and autotrophic bacteria were studied. The autotrophic granules were characterized by smaller granule size
higher density
higher concentration of extracellular polymeric substances (EPS) and weaker strength compared with the heterotrophic ones. The diameter and density of autotrophic granules were changed in the same fashion
resulting in stable granules
and the heterotrophic granule
however
grew up with the increase of diameter and the decrease of density. According to the strength analysis
it is proposed that in the autotrophic system
the balance between EPS and porosity is the main reason for the long term stability. However
the balance could not be obtained in the heterotrophic system and that the operational conditions could not control the overgrowth of filamentous bacteria was the reason for the instability.