| Author | Fortuno, Nenita B. |
| Call Number | AIT Thesis no.EV-90-4 |
| Subject(s) | Sewage--Purification--Activated sludge process
|
| 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 | Laboratory-scale experiments were conducted to evaluate the
effects of increasing organic loadings on the performance of a
continuous anoxic baffled reactor-aerobic activated sludge
process in removing COD, nitrogen and phosphorus from low to
medium-strength synthetic wastewater using glucose as the major
substrate . Four organic loadings corresponding to influent COD
levels of 200, 400, 600 and 800 mg/L were tested . The SCOD
removal efficiencies in all the runs were all above 95% as
expected since all the organic loadings tested were relatively
low and an easily biodegradable substrate was. utilized as carbon
source.
Nitrification was the limiting mechanism in achieving
complete nitrogen removal. At the same influent TKN
concentration, nitrogen removal was maximum (61%) at the lowest
organic loading due to substrate inhibition effects on the
nitrifying organisms.
At low organic loadi ngs (corresponding to influent COD
levels of 200 and 400 mg/L), the SCOD profile along the treatment
system revealed that almost all the carbon source were utilized
for the biological activities taking place in the anoxic reactor.
The expected biological phosphorus release and uptake mechanisms
did not take place as evidenced by the ortho-P and total- P
profiles probably due to insufficient Acinetobacter population.
As a result, the maximum total- P removal was only 38% at an
initial COD and P concentrations of 400 and 25 mg/L respectively.
Assimilation seemed to be responsible for the major
fraction of SCOD and nitrogen removal in the system. However,
the results were subject to the limitations of the techniques
used to obtain the mass balance .
The efficiencies obtained under batch conditions with
respect to COD, nitrogen and phosphorus removal were within the
same range of values as those attainable under continuous-flow
runs. However, the specific SCOD and NH4+- N removal and NO~ --N
production and removal rates were higher under batch conditions
due to the higher initial substrate concentration relative to
continuous runs. |
| Year | 1990 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Environmental Engineering (EV) |
| Chairperson(s) | Harada, Hideki |
| Examination Committee(s) | Chongrak Polprasert ;Mino, Takashi
|
| Scholarship Donor(s) | The French Government |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1990 |