| Author | Natapol Boonthanon |
| Call Number | AIT Thesis no.EV-00-10 |
| Subject(s) | Water--Purification--Organic compounds removal
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| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | Biological granular activated carbon coupled with microfiltration membrane, also called membrane bioreactor, is a promising technology used as pretreatment of biodegradable organic content from seawater prior to reverse osmosis membrane. The expe1imental investigations were conducted by using lab-scale experiments, which were separated into three stages. In the first stage, the batch expe1iments were conducted in order to determine the optimum operating condition for biological granular activated carbon filter and kinetic coefficients of bacteria in biological granular activated carbon. The effects of operational mode, empty bed contact time, initial dissolved organic carbon concentration and temperature were studied in this stage. It was concluded that fluidized bed biological granular activated carbon, run at 15 min empty bed contact time, with initial seawater dissolved organic carbon concentration 6-8 mg/L can be utilized effectively to remove nearly 100% biodegradable dissolved organic carbon from seawater. In the second stage, continuous expe1iments of membrane bioreactor and control membrane reactor were conducted concomitantly in order to gain an insight into the long-term effect of membrane bioreactor on biodegradable organic content removal and biofouling control. The optimum conditions from first stage experiment were used in the biological granular activated carbon part of membrane bioreactor. The results showed that biodegradable dissolved organic carbon removal in biological granular activated carbon still reached the same level with the results of first stage experiment, which were nearly 100% but in term of biofouling control on microfiltration membrane, membrane in membrane bioreactor fouled more rapidly than in control membrane reactor. Albeit, biofouling of microfiltration membrane was still a prominent problem of membrane bioreactor, chemical membrane cleaning with alkaline solution can readily remove these foulants and restore the filtration flux to nearly original level. Moreover it was found that dissolved oxygen, pH and salinity had a little effect on bacteria degradation. During the third stage, raw seawater, filtrate from membrane bioreactor and from control membrane reactor were filtered through reverse osmosis membrane in order to evaluate the effect of seawater pretreatment on biofouling control on reverse osmosis membrane. The results showed that filtrate from membrane bioreactor yielded the highest permeate flux improvement, which was approximately 300 % compared with raw seawater. |
| Year | 2000 |
| 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) | Samom Muttamara;Fukushi, Kensuke;Sathasivan, Arumugams; |
| Scholarship Donor(s) | Asian Institute of Technology |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2000 |