Integrating the UV/O3 process into attached growth membrane bioreactors to treat polluted surface water | |
| Author | Thanwarat Chan |
| Call Number | AIT Thesis no.EV-17-28 |
| Subject(s) | Membrane reactors Bioreactors |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Environmental Engineering and Management |
| Publisher | Asian Institute of Technology |
| Abstract | Treatment of polluted surface water has become the important issue in drinking water treatment due to the increasing of recalcitrant organic compounds in surface water. The recalcitrant organic compounds were not readily degraded by biological system. The advanced oxidation processes (AOPs) were used to transform the recalcitrant compound to biodegradable organic compounds which easily degrade by microorganisms in biological process. The attached growth membrane bioreactor (aMBR) was applied to treat pollutants in surface water, but it was ineffective to remove recalcitrant compounds. So, the AOPs including UV, O3 and UV/O3 which was used as post-treatment was used to improve the organic removal in aMBR effluent with CODMn between 3 to 5 mg/L. In this study, the mechanism of aMBR effluent after treated UV, O3 and UV/O3 was studied and compared. The mechanism study investigated removal performance, biodegradability analysis, molecular weight fraction, and fluorescence excitation emission matrices analysis, hydrophobic and hydrophilic fraction. The removal performance show that the use of UV/O3 process after aMBR system was found to be the most effective for organic matter reduction, with CODMn, UV254 and color reduced by 12, 66 and 87%, respectively. The UV/O3 process had the highest performance in improving the biodegradability in treating aMBR permeate. The fraction analysis of aMBR effluent treated by UV/O3 process revealed that the organic matter with molecular weight less than 1 kDa increased more than 80% and the hydrophilic fraction by more than 40%. These results show that the UV/O3 was more effective to improve recalcitrant organic compounds removal compared with UV and O3 process alone. However, the aMBR effluent after treated by UV/O3 process was returned to aMBR system with 60% recirculation ratio. The aMBR effluent after treated by UV/O3 process with and without recirculation was tested and compared. It was found that the aMBR effluent after treated by UV/O3 process with recirculation was slightly more effective than without recirculation. The removal performance in recirculation system was higher than without recirculation system only 23 and 3% in term of CODMn and UV254. Furthermore, the percentage of hydrophilic fraction and organic with MW less than 1 kDa was decreased after recirculation. The aMBR effluent treated by UV/O3 contained the biodegradable organic matter and it can be treated by microorganism in aMBR system. |
| Year | 2017 |
| 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 and Management (EV) |
| Chairperson(s) | Visvanathan, C.; |
| Examination Committee(s) | Annachhatre, Ajit P.;Shipin, Oleg V.; |
| Scholarship Donor(s) | Greater Mekong Subregion (GMS) Scholarship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2017 |