| Author | Arora, Sanjay |
| Call Number | AIT Thesis no. EV-90-21 |
| Subject(s) | Sewage--Purification--Biological treatment
|
| 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 | Multi Stage Reversing Flow Bioreactor (MRB) uses new
biological interaction among sulfur bacteria for organic substrate
removal under biological environments different from aerobic and
anaerobic. The biological interaction between sulfate reducing bacteria
and sulfide oxidising bacteria is responsible for COD and SS removal from
wastewater.
An experimental study to determine mechanism and operating
conditions of MRB was carried out. Batch experiment and
microscopic observations were taken to support the mechanism of MRB.
Performance of MRB under three different hydraulic conditions was studied
and effect of organic loading and wastewater recycle was also studied.
Organic substrate removal was due to aerobic metabolism in aeration
vessels and due to sulfur metabolism in biological vessels. Only
about 1% of total COD removal was due to methanogenesis in
biological vessels and assimilation of sulfur microorganisms was the
main mechanism responsible for COD removal . Yield coefficient of
MRB process was found to vary between 0.1-0 .2.
At flow rate of 0.78 l/min (upflow velocity 73 m/day) 85-90 % of
COD removal efficiency was achieved and effluent SS was between 15-20
mg/l. At flow rate of 1.17 l/min (upflow velocity 109 m/day) , without
recycle 70-80 % of COD removal efficiency was obtained and SS was
between 30-40 mg/l. However with recycling of wastewater 84- 88 %
of COD removal efficiency was achieved even at a flow rate of 1.17 l / min. |
| Year | 1990 |
| 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) | Mino, Takashi
|
| Examination Committee(s) | Chongrak Polprasert ;Verink, Johan ;Harada, Hideki
|
| Scholarship Donor(s) | The Royal Norwegian Government (Norade Scholarship) |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1990 |