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Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
Electrolytically aided denitrification on a rotating biological contactor
Joanna Rodziewicz1, Urszula Filipkowska, Ewa Dziadkiewicz
1Faculty of Environmental Sciences and Fisheries, University of Warmia and Mazury in Olsztyn, Prawochenski St. 1 Olsztyn, Poland. joanna.rodziewicz@uwm.edu.pl
Environmental Technology
|April 9, 2011
Summary
Applying electric current to rotating biological contactors enhances nitrogen removal from wastewater. The optimal current density of 0.2 A m(-2) significantly improved both denitrification and nitrification efficiencies.
Area of Science:
- Environmental Science
- Environmental Engineering
- Water Treatment
Background:
- Wastewater treatment processes are crucial for removing pollutants like nitrogen.
- Rotating biological contactors (RBCs) are commonly used for biological wastewater treatment.
- Enhancing the efficiency of nitrogen removal in RBCs is an ongoing challenge.
Purpose of the Study:
- To investigate the effect of electric current on nitrogen removal in a rotating biological contactor.
- To determine the optimal electric current density for maximizing nitrogen removal efficiency.
Main Methods:
- Bench-scale rotating biological contactor experiments were conducted.
- Municipal wastewater with organic and ammonium nitrogen was treated.
- Electric currents of 0.2 A m(-2), 0.8 A m(-2), and 1.5 A m(-2) were applied.
- Stainless-steel discs with immobilized biofilm served as the cathode.
Main Results:
- The highest nitrogen removal efficiency was achieved at an electric current density of 0.2 A m(-2).
- Denitrification efficiency exceeded 64% under optimal conditions.
- Nitrification efficiency reached 93.4% with the applied electric current.
Conclusions:
- Application of electric current can significantly enhance nitrogen removal in RBCs.
- A current density of 0.2 A m(-2) is optimal for improving both nitrification and denitrification.
- Electrically enhanced RBCs show promise for more effective wastewater nitrogen management.
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