Decentralized wastewater treatment and reclamation using membrane bioreactor | |
| Author | Nguyen Hoai Nam |
| Call Number | AIT Thesis no.EV-06-20 |
| Subject(s) | Membrane reactors Bioreactors Sewage--Purification--Biological treatment |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | The aim of decentralized approach is help to strict treatment of wastewater before discharge into environment. Hence, onsite system performance is a function of decentralized wastewater treatment. The most popular of onsite treatment system is septic tank. At present, in user point of view, it is perfectly treatment system. That means wastes are treated appropriate when discharge into septic tank. However, the several studies reported that effluent septic tank is poor quality. It contains high concentration of SS, COD, TKN and Ammonia. In order to get effective of onsite treatment system, the appropriate performances concerned with high quality effluent are required. Two modes of monitoring septic tanks were carried out which are normal operation and sludge withdrawal operation. Total 10 septic tanks were chosen to monitor for 6 months duration. Among them, monitoring of 8 septic tanks were carried out at normal operation mode and 2 remaining were withdrawn all sludge to monitor. The result of normal operation mode showed that SS, COD, TKN and Ammonia at high concentration were contaminated wastewater in these septic tanks. The results of sludge withdrawal mode indicated that it took 8 weeks for septic tanks recovered to normal operation condition and SS was significant reduced after withdrawn sludge. The measuring results of MFI, particle size distribution and specific resistance indicated that effluent septic tank has biggest mean diameter of particle with high potential of membrane fouling and high specific resistance compare to the mixed liquor of aerobic, anaerobic process and raw wastewater from AIT. Two lab scale MBR processes, aerobic and anaerobic process, were carried out to treat effluent septic tank. The experiment was investigated of HRT 8 and 16 hours for both processes. It was noted that there was no removal efficiency for anaerobic process. The removal efficiencies in aerobic process were 80% of COD and 60% of TKN and Ammonia. The treated wastewater by aerobic process is acceptable to reuse for agriculture, gardening or unrestricted areas The main issue of this experiment is rapid clogging of membrane. At HRT 16 and 8 hours in anaerobic process, membrane was clogged after 16 and 6 hours. However, it was longer in aerobic process, membrane was clogged after 9 and 23 days of operation, respectively |
| 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) | Nguyen Thi Kim Oanh ;Thammarat Koottatep ; |
| Scholarship Donor(s) | Ministry of Education and Training Vietnam; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2006 |