TY - JOUR
T1 - Active biomass estimation based on ASM1 and on-line OUR measurements for partial nitrification processes in sequencing batch reactors
AU - Lindow, Franklin
AU - Muñoz, Carlos
AU - Jaramillo, Francisco
AU - Bishop, Robert H.
AU - Proal-Nájera, José B.
AU - Antileo, Christian
N1 - Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/11/1
Y1 - 2020/11/1
N2 - The main challenge for partial nitrification is to reach stable nitrite accumulation, which strongly depends on the nitrite-oxidizing bacteria (NOB) growth in the reactor. The on-line estimation of active biomass may enhance the decision-making process to maintain a high nitrite accumulation in the reactor. In this work, we propose an active biomass estimator based on ASM1 and on-line oxygen uptake rate measurements (OUR-E) in a sequencing batch reactor. In order to validate the OUR-E, two operating scenarios were applied during 200 days of operation: unfavorable (sludge retention time (SRT) = 40 d, pH = 7.6, dissolved oxygen (DO) = 2 mg/L) and favorable for partial nitrification (SRT = 10 d, pH = 8.5, DO = 2 mg/L). Furthermore, a second estimation method based on off-line measurements of N-species concentrations (Nsp-E) was implemented to evaluate the performance of the OUR-E. The OUR-E was able to predict a reduction in the NOB active fraction from 10.3% to 1.6% with nitrite accumulation over 80% when we shifted the operating scenario. Although both estimators predicted similar results, the OUR-E showed a better prediction quality than the Nsp-E, according to Theil's coefficient of inequality.
AB - The main challenge for partial nitrification is to reach stable nitrite accumulation, which strongly depends on the nitrite-oxidizing bacteria (NOB) growth in the reactor. The on-line estimation of active biomass may enhance the decision-making process to maintain a high nitrite accumulation in the reactor. In this work, we propose an active biomass estimator based on ASM1 and on-line oxygen uptake rate measurements (OUR-E) in a sequencing batch reactor. In order to validate the OUR-E, two operating scenarios were applied during 200 days of operation: unfavorable (sludge retention time (SRT) = 40 d, pH = 7.6, dissolved oxygen (DO) = 2 mg/L) and favorable for partial nitrification (SRT = 10 d, pH = 8.5, DO = 2 mg/L). Furthermore, a second estimation method based on off-line measurements of N-species concentrations (Nsp-E) was implemented to evaluate the performance of the OUR-E. The OUR-E was able to predict a reduction in the NOB active fraction from 10.3% to 1.6% with nitrite accumulation over 80% when we shifted the operating scenario. Although both estimators predicted similar results, the OUR-E showed a better prediction quality than the Nsp-E, according to Theil's coefficient of inequality.
KW - ASM1
KW - Active biomass estimator
KW - OUR
KW - Partial nitrification
KW - State observer
UR - http://www.scopus.com/inward/record.url?scp=85089008323&partnerID=8YFLogxK
U2 - 10.1016/j.jenvman.2020.111150
DO - 10.1016/j.jenvman.2020.111150
M3 - Artículo
C2 - 32768763
AN - SCOPUS:85089008323
SN - 0301-4797
VL - 273
JO - Journal of Environmental Management
JF - Journal of Environmental Management
M1 - 111150
ER -