| Author | Chiraphorn Kornsitthikul |
| Call Number | AIT Thesis no.EV-98-28 |
| Subject(s) | Sewage--Purification--Ozonization
|
| 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 | Three treatment systems, namely ozonation, activated sludge and combination of
preozonation and activated sludge were investigated for the removal of COD, BOD, Oil &
Grease and TSS from petrol station wastewater. All experiments were run in batch mode.
The application of ozone in petrol station wastewater was effective to oil removal.
Three ozone dosages of 4. 63, 10.30 and 14.08 mg 0 3/L 0 2 were used in this study. The
optimum conditions were accomplished at ozone dosage of 14.08 mg 0 3/L 0 2, contact time
of 60 minutes and at neutral pH. The removal efficiencies of COD, BOD, TSS and Oil &
Grease were be 60.713, 69.103, 53.443 and 65.593 respectively. The pH of wastewater
showed great influence on the efficiency of ozonation. Ozonation can promote
biodegradability and also destabilize the suspension of wastewater. However, in some cases,
ozonation gave negative effect on biodegradability.
Biological treatability of this wastewater was also carried out in this study. The
activated sludge systems were operated with two organic loading levels (F/M ratio) of 0.25
and 0.38. The removal efficiencies of COD and Oil & Grease with F/M ratio of 0.25 were
found to be higher than those of 0.38, but detention time of the former was twice higher than
that of the later.
Further investigations on effect of preozonation at different pH on perfo rmance of
the sequential activated sludge treatment system were also made. The results indicated that
the pH conditions of the preozonation step played a significant role in the subsequent
biological treatment processes. BOD removal efficiency of preozonation at low pH was
higher than that of individual treatment. |
| Year | 1998 |
| 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) | Samorn Muttamara; |
| Examination Committee(s) | Takizawa, Satoshi ;Dahl-Madsen, Karl Iver; |
| Scholarship Donor(s) | Government of the United Kingdom ; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1998 |