title: Solids Retention Time Dependent Phototrophic Growth and Population Changes in Chemostat Cultivation Using Wastewater.
abstract: There has been renewed interest in using algae for wastewater polishing and treatment in recent years. Because solids retention time (SRT) is a key design and operating parameter in bioreactor operation, this research determined the effect of SRT on phototrophic growth and microbial population dynamics in continuous-flow chemostat systems. There was a unique feature of phototrophic growth that differed from chemotrophic growth in chemostat. It was found that the phototrophic biomass concentration increased proportionally as SRT increased from 3 to 9 days. Regardless of the change in SRT, a step function model was successfully applied with the predicted phototrophic production rate of 4.5 ± 0.9 g/m(2)·d at the light intensity of 68.5 μmol/m(2)·s. Even though the continuous-flow systems were initially seeded with a 1:1 mixture of green algae and cyanobacteria, Chlorella vulgaris always dominated (98%) in the continuous-flow chemostat systems under steady-state conditions.
authors.affiliation: Department of Civil and Environmental Engineering, University of Missouri, E2509 Lafferre Hall, Columbia, MO 65211, USA.
authors.forename: Qi
authors.initials: Q
authors.lastname: Shen
authors.forename: Judy D
authors.initials: JD
authors.lastname: Wall
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Hu
mesh_terms: D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D048408:Chlorella vulgaris / Q000378:metabolism*; D046931:Microcystis / Q000378:metabolism*; D008962:Models, Theoretical; D052817:Phototrophic Processes; D011157:Population Dynamics; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000382:microbiology*
chemical_list: D062065:Wastewater