title: Impact of worm predation on pseudo-steady-state of the circulating fluidized bed biofilm reactor.
abstract: This paper studies integrated simultaneous carbon and nitrogen removal as well as worm predation, in a circulating fluidized bed biofilm reactor (CFBBR) operated with an anoxic-aerobic bioparticle recirculation. A lab-scale CFBBR with a 8.5-liter reaction zone comprising 2L anoxic and 6.5L aerobic compartments was designed to evaluate the aquatic Oligochaete worm effect. Long-term (200 days) performance showed that stable and high-rate chemical oxygen demand (COD) with sodium acetate as the carbon source and total nitrogen (NH(4)Cl as nitrogen source) conversions were achieved simultaneously, with low sludge production of 0.082 g VSS (volatile suspended solids) g COD(-1) at pseudo-steady-state. Worm predation, which causes considerable sludge reduction of the bioparticle process, was studied. The results proved that the worm predation has a significant impact on the pseudo-steady-state performance of the CFBBR, decreasing biomass yield, decreasing oxygen concentration and increasing expanded bed height.
authors.affiliation: Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Canada N6A 5B9.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: George
authors.initials: G
authors.lastname: Nakhla
authors.forename: Jesse
authors.initials: J
authors.lastname: Zhu
mesh_terms: D000818:Animals; D001421:Bacteria, Anaerobic / Q000502:physiology*; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors / Q000382:microbiology* / Q000469:parasitology*; D009584:Nitrogen / Q000378:metabolism*; D009835:Oligochaeta / Q000502:physiology*; D010100:Oxygen / Q000378:metabolism*; D011235:Predatory Behavior / Q000502:physiology
chemical_list: D009584:Nitrogen; D010100:Oxygen