Related Experiment Video
Updated: Dec 16, 2025

Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
Effective nitrogen removal from ammonium-depleted wastewater by partial nitritation and anammox immobilized in
Matthieu Landreau1, Samuel J Byson1, HeeJun You1
1Department of Civil and Environmental Engineering, University of Washington, 201 More Hall, Box 352700, Seattle, WA, 98195-2700, USA.
Abstract:
This study investigates the effect of physicochemical conditions on the partial nitritation and anammox treatment by immobilized ammonia oxidizers under ammonium-deplete conditions. The impact of oxygen and temperature was studied by measuring the activity of immobilized aerobic and anaerobic ammonia-oxidizing organisms (Ammonia-oxidizing bacteria (AOB) and archaea (AOA), and Anammox bacteria) embedded in polyvinyl alcohol - sodium alginate (PVA-SA) beads and in thin layer poly-ethylene glycol hydrogels. Beads and flat hydrogels were incubated in a fluidized bed reactor (FBR) and in two flow cells, respectively. Both systems were fed with synthetic wastewater (15 mg N-NH4+/L) at different temperatures (20 °C and/or 30 °C) and different dissolved oxygen (DO) concentrations (0.1, 0.3, 0.5 and/or 1 mg/L) over 152 and 207 days, respectively. The FBR system had a maximum removal rate of 1.7 g-N/m3/d at 0.1 mg O2/L, corresponding to 80% removal efficiency, while a high aerobic ammonia-oxidizing activity but a partial oxygen inhibition of Anammox bacteria were observed at higher DO concentrations. In both flow cells, nitrogen removal efficiency was highest (80%) at 30 °C and 1 mg O2/L while removal was less favorable at lower DO and lower temperature. Our results indicate a potential use of hydrogel beads for an energy efficient technology with reduced aeration demand for treating low ammonia wastewater, while layered hydrogels are a possible first step for biological treatments of wastewater using tangential flow. In addition, we provide blueprint drawings of the flow cells, which may be used to 3D-print the apparatus for other applications.
More Related Videos
08:05Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
08:13A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Related Concept Videos
Inorganic Nitrogen Assimilation
Overview of Nitrogen Metabolism
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
Metabolism of Chemolithotrophs
Preparation of Amines: Alkylation of Ammonia and Amines
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
2° Amines to N-Nitrosamines: Reaction with NaNO2
The Nitrogen Cycle