Nitrification in Activated Sludge Exposed to Static Magnetic Field.
The study investigated wastewater treatment in an aerobic reactor with activated sludge exposed to static magnetic field (SMF) with mean induction of 8.1 mT. The efficiency of chemical oxygen demand removal was about 90% in a control reactor and an SMF-exposed reactor. Although the nitrification efficiency was higher than 95% in both reactors, the activity of ammonia-oxidizing bacteria was higher in the SMF-exposed reactor. This resulted in shortening of nitrification time to 4 h compared to 8 h in the control reactor. Higher number of ammonia-oxidizing bacteria in the SMF-exposed reactor might result from increased oxygen penetration into the liquid exposed to SMF, which favored growth of these bacteria. The results indicate that SMF enhanced nitrification, the most sensitive process from the biological nitrogen transformations. SMF influenced the overall biomass content that was 14% higher in the SMF-exposed reactor than in the control reactor.
Department of Environment Engineering, University of Warmia and Mazury in Olsztyn, Warszawska 117, 10-720 Olsztyn, Poland.
Marcin
M
Zieliński
Department of Environmental Biotechnology, University of Warmia and Mazury in Olsztyn, Słonczena 45G, 10-709 Olsztyn, Poland.
Agnieszka
A
Cydzik-Kwiatkowska
Department of Environmental Biotechnology, University of Warmia and Mazury in Olsztyn, Słonczena 45G, 10-709 Olsztyn, Poland.
Magdalena
M
Zielińska
Department of Environment Engineering, University of Warmia and Mazury in Olsztyn, Warszawska 117, 10-720 Olsztyn, Poland.
Marcin
M
Dębowski
Department of Environment Engineering, University of Warmia and Mazury in Olsztyn, Warszawska 117, 10-720 Olsztyn, Poland.
Paulina
P
Rusanowska
Department of Environment Engineering, University of Warmia and Mazury in Olsztyn, Warszawska 117, 10-720 Olsztyn, Poland.
Joanna
J
Kopańska
Nitrification; Static magnetic field; amoA gene copy number