Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/26/1997
Publication Date: N/A
Technical Abstract: Encapsulated nitrifiers are used in municipal wastewater treatment plants for higher nitrification rates and smaller reactors. We evaluated if this technology can be also used for treatment of swine wastewater. Acclimated nitrifying cells were immobilized in 3- to 5-mm PVA polymer pellets. Swine wastewater was treated in aerated fluidized biorectors with a 15.3% (w/v) pellet concentration and a screen to retain the pellets. In batch experiments, 14 h were needed for total conversion of ammonia-N (approx. 250 mg N/L) into nitrate-N. In contrast, it took 10 days for a control(no-pellets) treatment to start nitrification, and 69% of N was lost by air stripping. Ammonia removal efficiencies of more than 90% were obtained in continuous flow treatment using ammonia loading rates of 418 mg N/L/d and hydraulic residence time (HRT) of 12 h. The rate of nitrification of swine wastewater obtained with HRT of 4 h was 604 mg N/L/d. The high nitrification rates obtained in this study indicate that the encapsulated nitrifiers technology has potential application for animal waste treatment systems.