CultiCultivating aerobic granular sludge in a lab-scale sequencing batch reactor - Removal of pharmaceutically active compounds, total phosphorus, total nitrogen and organic matter from a complex synthetic wastewater
Typ
Examensarbete för masterexamen
Program
Infrastructure and environmental engineering (MPIEE), MSc
Publicerad
2020
Författare
Calgaro, Johan
Trieb, Linn
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Pharmaceutically active compounds (PhACs) in wastewater effluents pose a threat to both the
environment and humanity and, due to disadvantages associated with commonly implemented
advanced treatment methods for PhAC removal, it is of interest to investigate advanced biological
treatment alternatives for the removal of PhACs from wastewater. Since aerobic granular sludge
(AGS) possesses several advantages in comparison to the conventional activated sludge process,
it is of great interest to investigate as a new alternative for the biological treatment of PhACs. This
master thesis project was a part of the start-up of a PhD project investigating the potential of AGS
cultivated in a lab-scale sequencing batch reactor (SBR) to remove PhACs from wastewater. The
overall aim of this master thesis project was to successfully cultivate aerobic granules in the labscale
SBR, to theoretically evaluate its removal potential of nine selected PhACs and to reach a
sufficient reduction of total nitrogen (TN), total phosphorus (TP) and organic matter, expressed as
TOC. The performances of the lab-scale SBR were monitored for 29 days by collecting samples
from the reactor during different cycle phases and effluent. The dissolved concentration of the
investigated contaminants was analysed and the biomass characteristics were evaluated based on
the assessment of total suspended solids (TSS), volatile suspended solids (VSS), sludge volume
index (SVI), solid retention time (SRT), and sludge morphology by light microscopy. Results
showed that the formation of aerobic granules was initiated, but not fully achieved during the
observation time. The reactor accomplished nitrogen, phosphorus and, organic removal. High TOC
(>90 %), TP (>85 %), and TN (>80 %) removals were achieved by this system. The removal
potential of selected PhACs was theoretically evaluated based on relevant findings in a literature
review. Overall, it could be concluded that AGS cultivated in a SBR shows potential for the
removal of PhACs from wastewater due to the several unique characteristics, such as the easy
adjustment of the operational parameters. However, future research is needed to fully determine
the potential of using AGS cultivated in an SBR for PhAC removal.
Beskrivning
Ämne/nyckelord
Aerobic granular sludge , sequencing batch reactor , pharmaceuticals , pharmaceutically active compounds , wastewater , advanced biological treatment