| Author | Yuthana Tanwongwan |
| Call Number | AIT Thesis no. EV-94-29 |
| Subject(s) | Sewage--Purification--Activated sludge process
|
| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Science, School of Environment, Resources & Development |
| Publisher | Asian Institute of Technology |
| Abstract | It is known that A/O process can produce well-settling sludge. But sludge bulking can also
occur in these processes due to some causes such as composition of wastewater, operating
conditions, and, configurations of the systems. From this experiment, it has been observed that
0.2 mIJL of acetic acid can cause zoogloea bulking in A/O processes which had only two
anaerobic tanks but the process that had three anaerobic tanks can control this kind of bulking.
It also has been observed that strictly anaerobic initial contact zone (ICZ) can suppress
filamentous bulking more effective than anoxic one. Furthermore, some of unsuitable operating
conditions , i.e. too low organic loading, too high return sludge ratio, and too long influent
hydraulic retention time can deteriorate sludge settleability and phosphorus removal efficiency but
improve the removal efficiency of nitrogen.
Additionally, it has been found that concept of contact stabilization activated sludge, i.e.
reaeration of return sludge, is difficult to be applied with A/O process because it can introduce
small amount of dissolved oxygen into ICZ so filamentous bacteria can use this 00 as electron
acceptor in their metabolic mechanisms. Floes in units which had reaeration were very small size
and not compact. |
| Year | 1994 |
| 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) | Samom Muttamara |
| Examination Committee(s) | Lee, Seong-Key ;Umita, Teruyuki
|
| Scholarship Donor(s) | Royal Thai Government |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 1994 |