Pentachlorophenol degradation in membrane bioreactors | |
| Author | Le Ngoc Thu |
| Call Number | AIT Thesis no.EV-04-08 |
| Subject(s) | Pentachlorophenol Bioreactors--Fluid dynamics Membrane reactors |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. EV-04-08 |
| Abstract | Pentachlorophenol (PCP) and sodium pentachlorophenol has been used as a pesticide, herbicide, antifungal agent, bactericide and wood preservative, which can cause environmental pollution. The potential of using membrane bioreactor for treating PCP contaminated wastewater has been accessed. Synthetic wastewater includes PCP and glucose has COD around 600 mg/L was using in this study. During different loading stages in the range of 12 to 40 mg/m3.day of the MBR operation, a removal rate of 99% of PCP and 95% of COD could be achieved at hydraulic retention time of 12 hours and mixed liquor suspended solid of 10,000 mg/L. With NaPCP loading from 20-200 mg/m3.day (10- 100 mg/Lin the influent), the capacity of removal in terms ofNaPCP was still higher than 99% as well as more than 96% of COD. In this study with high concentration of biomass, biosorption played an important role besides the biodegradation process. The equilibrium time of 60 min was achieved and biosorption was found 0.6289mg/gVSS. This phenomenon could enhance the PCP degradation though increase the contacting between microorganism and contaminant. Mycobacterium chlorophenolicum had lower capacity in mineralization PCP compared with activated sludge from reactors. It also did not grow on NaPCP environment. Predominant microorganism Rl-Cl, Rl-C2, R2-Cl, and R2-C2, R2-C4 that could degrade PCP were isolated from the membrane bioreactor systems depending on their colony morphology. Their log phase was in the range of 18-72 hours and applied for bioaugmentation technique to enhance the performance of system in inhibition case. The inhibition level of NaPCP for different kind of predominant organism was different. 150mg/L (300 mg/m3.day) in the influent was found causing inhibition. Membrane resistance was low (14 K.Pa) after more than 100 days of operation. The toxic level of the influent make an increase in viscosity of the mixed liquor though producing more bound EPS to protect microorganism to the adverse environmental condition. The result was faster increased in transmembrane pressure. |
| Year | 2004 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. EV-04-08 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Environmental Engineering and Management (EV) |
| Chairperson(s) | Visvanathan, Chettiyappan |
| Examination Committee(s) | Nguyen Cong Thanh; Preeda Parkpian |
| Scholarship Donor(s) | The Royal Netherlands Government |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2004 |