Name: Maria Butrón Sevillano
Type: MSc dissertation
Publication date: 09/03/2018
Advisor:
Name |
Role |
|---|---|
| Ricardo Franci Gonçalves | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| Ricardo Franci Gonçalves | Advisor * |
Summary: The Anaerobic baffled reactor (ABR) has been an interesting alternative for the treatment of domestic sewage due to its low implantation and operation costs. This study evaluated the behavior of sludge and the performance of an ABR, with three 1.6 m3 independent compartments, under different hydraulic retention times (HRT). During 237 days, the ABR was operated under HDT of 13, 10, 8 e 6 hours, each stage lasting two months. The organic loading rates applied were 0.76, 0.73, 0.99 and 1.34 kg CODtotal/m3.d and biological organic loads applied were 0.14, 0.07, 0.11 and 016 KgCODtotal/KgVTS.d, for 13, 10, 8 and 6 hours of HRT, respectively. The ABR was monitored in terms of temperature, pH, alkalinity, total solids, fixed and volatile solids, suspended solids, sedimentable solids, COD (filtered and total), total phosphorus, NTK for liquid phase, as well as by solids profile (total, volatile and fixed), sludge volumetric index (SVI), granulometry, scanning electron microscopy (SEM) and sludge methanogenic activity (SMA) for the solid phase.The total COD removal efficiency was 51%, 44%, 41% and 39% for HRT of 13, 10, 8 e 6 hours, respectively. In terms of soluble COD, ABR presented efficiencies of 35%, 43%, 38% and 37% for the same HRT. The results obtained suggest that the ABR performance decreasing, specially in terms of total COD, is associated to the flowrate increasing. In addition, through the solids profile monitoring, it was also observed a sludge washout from the first compartment to the second and third ones. The Specific Methanogenic Activity (SMA) results indicate a biomass stratification, due to a biomass displacement, as the HRT was decreased.
