plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111elSSN : 2287-8815
Evaluation of Nitrification Characteristics in a Moving Bed Biofilm Reactor(MBBR) under Varying TAN Loading Rates in a Seawater RecirculatingAquaculture System (RAS)
이재건·김승리·박정환1*
국립부경대학교 수산생물학과, 1어번대학교 수산양식 및 수생과학과
This study quantified the nitrification characteristics and operational limits of a moving bed biofilm reactor (MBBR) in a seawater recirculating aquaculture system (RAS) under increasing total ammonia nitrogen (TAN) loading rate (TLR). Eight independent culture tank-biofilter systems were operated at 33±2 psu, pH 7.5±0.5, and 22.5±0.5°C, and TAN loading was reproduced by continuously dosing a synthetic nutrient solution using a metering pump. Each system was run at steady state across a TLR range of 0.1-1.2 g TAN·m-2·day-1, and influent·effluent TAN, nitrite nitrogen (NO2-N), and removal efficiency were evaluated. The relationship between TAN influent and areal TAN removal rate (ATR) followed Michaelis-Menten kinetics, yielding an Rmax of 1.0705 g TAN·m-2·day-1 and KS of 89.1845 mg·L-1 (R2=0.9689). At low TAN (0-6 mg·L-1), ATR increased nearly linearly, y=0.0113+0.0257x (R2=0.9969). TAN exceeded 10 mg·L-1 from TLR 0.6, and NO2-N increased sharply from 5 mg·L-1 to > 600 mg·L-1 between TLR 0.4 and 0.6. These results suggest that increasing loading under seawater conditions increases the risk of TAN and NO2-N accumulation. Therefore, a practical upper TLR for safe design and operation is approximately 0.4 g TAN·m-2·day-1, with the linear model derived for the low-TAN range serving as a reference in this range.
Recirculating aquaculture system, Moving bed biofilm reactor, TAN loading rates, Nitrification, Michaelis- Menten model