Bioaugmentation as a tool for improving the start-up and stability of a pilot-scale partial nitrification biofilm airlift reactor.
The effectiveness of bioaugmentation in the improvement of the start-up of a biofilm airlift reactor to perform partial nitrification was investigated. Two identical biofilm airlift reactors were inoculated. The non-bioaugmented reactor (NB-reactor) was inoculated with conventional activated sludge, whereas the bioaugmented reactor (B-reactor) was seeded with the same conventional activated sludge but bioaugmented with nitrifying activated sludge from a pilot plant performing full nitritation under stable conditions (100% oxidation of influent ammonium to nitrite). The fraction of specialized nitrifying activated sludge in the inoculum of the B-reactor was only 6% (measured as dry matter). To simplify comparison of the results, operational parameters were equivalent for both reactors. Partial nitrification was achieved significantly faster in the B-reactor, showing a very stable operation. The results obtained by fluorescence in situ hybridization assays showed that the specialized nitrifying biomass added to the B-reactor remained in the biofilm throughout the start-up period.
Department of Chemical Engineering, Escola d'Enginyeria, Universitat Autònoma de Barcelona, Spain.
Albert
A
Bartrolí
Julián
J
Carrera
Julio
J
Pérez
D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D018441:Biofilms; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D052918:Environmental Restoration and Remediation / Q000295:instrumentation* / Q000379:methods*; D017404:In Situ Hybridization, Fluorescence; D058465:Nitrification; D010100:Oxygen / Q000032:analysis; D010865:Pilot Projects; D012995:Solubility; D013997:Time Factors
D010100:Oxygen