Chitosan membrane bioreactor for nitrification | |
| Author | An, Kyoung-jin |
| Call Number | AIT Thesis no.EV-99-12 |
| Subject(s) | Chitosan Nitrification |
| 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 |
| Abstract | This study deals with establishment and operation of a Membrane Bio-Reactor (MBR) using chitosan membrane for biological nitrification. Models are also established to estimate performance of membrane bioreactor. Chitosan membrane was fitted vertically inside the aeration tank of a laboratory scale conventional activated sludge process. The aeration tank thus became a hybrid growth reactor combining both suspended and fixed biomass. Characterization of chitosan membrane suggested its possibility as support for biofilm development. Theoretical mathematical models predicting the performance of the hybrid growth reactor were proposed and their accuracy was affirmed by comparison with the experimentally measured results. Thus, a new system of membrane bioreactor can be constructed at a reduced cost using chitosan membrane. Investigations on Chitosan Membrane Bio-Reactor (CMBR) were carried out in three separate reactor configurations namely Mixed Liquor Volatile Suspended Solid (MLVSS) Bio-Reactor (MMBR), Biofilm and MLVSS Bio-Reactor (MBBR), and Biofilm Bio-Reactor (BBR). Nitrification of 0.51 kg NH4-N/m3 /day was achieved in MBBR out of which 70-80 % nitrification occurred in biofilm and 20-30 % in suspended biomass. These studies indicate that 3-4 times higher nitrification rate can be achieve in MBBR as compare to suspended growth nitrification reactor. A mathematical model was constructed to describe performance of MBBR as MBBR consist both biomass and attached biomass. The model consists of a set of mass balance equations for dissolved oxygen and various nitrogen species. Monad kinetics was used to describe biochemical reactions taking place inside the biofilm. Numerical solution to the system of ordinary differential equations was obtained. Different cases with respect to bulk substrate penetration were identified and incorporated in the model. Effectiveness factor for nitrification was evaluated. |
| Year | 1999 |
| 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) | Annachhatre, Ajit P.; |
| Examination Committee(s) | Ozaki, H. ;Suwalee Chandrkrachang ; |
| Scholarship Donor(s) | Partial Scholarship ; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1999 |