TY - JOUR
T1 - Reduction of sewage sludge and N2O emissions by an Oxic Settling Anaerobic (OSA) process
T2 - The case study of Corleone (Italy) wastewater treatment plant
AU - Mannina, Giorgio
AU - Cosenza, Alida
AU - Di Trapani, Daniele
AU - Gulhan, Hazal
AU - Mineo, Antonio
AU - Bosco Mofatto, Paulo Marcelo
N1 - Publisher Copyright:
© 2023 The Authors
PY - 2024/1/1
Y1 - 2024/1/1
N2 - Biosolid management is becoming one of the most crucial issues for wastewater treatment plant (WWTP) operators. The application of the Oxic Settling Anaerobic (OSA) process allows the minimisation of excess sludge production. This study compares conventional activated sludge (CAS) and OSA layouts in a full-scale WWTP (namely, Corleone - Italy). Extensive monitoring campaigns were conducted to assess treatment performances regarding carbon and nutrient removal, greenhouse gas (GHG) emissions, excess sludge production, and biomass activity (by means of respirometric analysis). Results showed that the effluent quality consistently met the Italian discharge limits. However, with the implementation of the OSA process, there was a decrease in ammonium removal efficiency, which could be attributed to reduced nitrifier activity related to reduced biomass production and extended anaerobic conditions affecting the nitrification process. On the other hand, the OSA configuration significantly increased phosphorus removal, indicating a high phosphorus content in the resulting waste sludge. A worsening of the sludge settling properties was observed with the OSA configuration likely due to decreased EPS concentrations. The sludge production in the OSA configuration decreased by 17.3 % compared to CAS. Nitrous-oxide measurements did not show a variation between CAS and OSA configurations, confirming that the OSA process can be a suitable solution for reducing WWTP's carbon footprint.
AB - Biosolid management is becoming one of the most crucial issues for wastewater treatment plant (WWTP) operators. The application of the Oxic Settling Anaerobic (OSA) process allows the minimisation of excess sludge production. This study compares conventional activated sludge (CAS) and OSA layouts in a full-scale WWTP (namely, Corleone - Italy). Extensive monitoring campaigns were conducted to assess treatment performances regarding carbon and nutrient removal, greenhouse gas (GHG) emissions, excess sludge production, and biomass activity (by means of respirometric analysis). Results showed that the effluent quality consistently met the Italian discharge limits. However, with the implementation of the OSA process, there was a decrease in ammonium removal efficiency, which could be attributed to reduced nitrifier activity related to reduced biomass production and extended anaerobic conditions affecting the nitrification process. On the other hand, the OSA configuration significantly increased phosphorus removal, indicating a high phosphorus content in the resulting waste sludge. A worsening of the sludge settling properties was observed with the OSA configuration likely due to decreased EPS concentrations. The sludge production in the OSA configuration decreased by 17.3 % compared to CAS. Nitrous-oxide measurements did not show a variation between CAS and OSA configurations, confirming that the OSA process can be a suitable solution for reducing WWTP's carbon footprint.
KW - Biological nutrients removal
KW - Environmental footprint
KW - Greenhouse gases
KW - Respirometry
KW - Wastewater treatment
UR - https://www.scopus.com/pages/publications/85174351020
U2 - 10.1016/j.scitotenv.2023.167793
DO - 10.1016/j.scitotenv.2023.167793
M3 - Article
C2 - 37838037
AN - SCOPUS:85174351020
SN - 0048-9697
VL - 906
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 167793
ER -
