Treatment of high-strength organic wastewater using an aerobic granular system with baffled membrane bioreactor | |
| Author | Nguyen Duc Minh |
| Call Number | AIT Thesis no.EV-06-19 |
| Subject(s) | Membrane reactors Bioreactors |
| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | Aerobic granular system was investigated to overcome disadvantages of conventional treatment system. Because of its prominent advantages, such as: high MLVSS concentration, good settling ability, etc. aerobic granular system could be applied for treating high strength wastewater. In this study, synthetic wastewater and basalts as carriers were used to cultivated aerobic granules in two kinds of reactor: Sequencing Batch Airlift Reactor (SABR) and Sequencing Batch Bubble Reactor (SBBR). The results showed that at OLR of 3 kgCOD/m3.d, aerobic granules were formed simultaneously in both SBAR and SBBR within 1.5 months. In the next step aerobic granular system was increased OLR to 20 kgCOD/m3.d to estimate the maximum and optimum OLR that system could suffer. It could be realized that after OLR exceed 20 kgCOD/m3.d, aerobic granules were unstable and easily worn. Only at OLR of 15 kgCOD/m3.d, aerobic granular system demonstrated stability and good treatment ability. Experimental data proved that settling ability of aerobic granules was 10 fold better than that of activated sludge (SVI of aerobic granules was less than 25 mug, while that value in activated sludge was 220 mL/g). Moreover at optimum OLR aerobic granular system always maintained at MLSS of 11230 and 12780 mg/L in SBAR and SBBR, respectively. Matured granule size could reach to 1.5 mm in SBAR and 1.7 mm SBBR, and then it proportionally varied with the increase of OLRs. In term of compactness, settled biomass concentration displayed that aerobic granules posed high biomass concentration. At OLR 17.5 kgCOD/m3.d, settled biomass concentration was 47.8 g/Lgranule in SBAR, and 53.7 granule in SBBR. Although SBBR always presented better aerobic granulation, it predicted to cause more fouling than SBAR through bound EPS results. The second objective of this study was to characterize effluent from aerobic granular system to evaluate fouling potential. By monitoring MLSS, EPS and MFI, it could be concluded that effluent from SBBR cause membrane fouling easier than that from SBAR. The third objective of this study was to monitor fouling behavior of PVDF flat sheet membrane (pore size of membrane was 0.1 m) in Baffled Membrane Bioreactors (MBR) connected to aerobic granular system. During 1.5 months of operation including 4 cycles, together with investigating EPS, MFI, it was concluded that bound EPS had influence on cake layer fouling whereas soluble EPS had significant impact on irreversible fouling |
| Year | 2006 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Environmental Engineering (EV) |
| Chairperson(s) | Visvanathan, C. |
| Examination Committee(s) | Shipin, Oleg ;Preeda Parkpian |
| Scholarship Donor(s) | Ministry of Education and Training, Vietnam |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2006 |