| Author | Shin, Hyun-kook |
| Call Number | AIT Diss. no. EV-87-2 |
| Subject(s) | Sewage lagoons
|
| Note | A dissertation submitted in the partial fulfillment of the requirements for the degree of Doctor of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | Research was conducted to improve waste stabilization pond (WSP)
performance through the installation of artificial media, made of
polyvinylidene chloride, in the laboratory-scale and pilot-scale
experimental pond units. The WSP incorporating attached-growth media are
called attached-growth waste stabilization ponds (AGWSP). The
experimental results obtained from this study showed that improved
performance of WSP could be achieved through the installation of
attached-growth media in the pond water. The media enhanced the growth
of attached biomass, especially heterotrophic bacterial concentrations
in the system, and consequently leading to better organic and nutrient
removal. The attached-growth media also attached or adsorbed some of the
dispersed growth microorganisms and other suspended solid particles, thus
less suspended solid concentrations present in the AGWSP effluents.
However, a distinct advantage with respect to fecal coliform removal could
not be observed, probably because of the clumping of fecal coliform cells
to the attached-growth media and some shading effects of the media itself.
Dissolved oxygen and pH values in the AGWSP water were slightly decreased
with increasing the media fraction in the pond.
Based on the kinetic studies, the maximum specific growth rate of
the heterotrophic bacteria was found to increase with increasing the media
fraction in the pond water, while the half-velocity constants were not
significantly affected.
Data from laboratory-scale AGWSP experiments showed better NH 3 -N
removal in the AGWSP units than those in the control units without
attached-growth media. The main mechanism of NH 3 -N removal in the AGWSP
units was found to be through biological uptake of NH 3 -N by the attached
and dispersed biomass, while volatilization and nitrification had little
effects on NH 3 -N removal. Regression equations of various NH 3 -N removal
rates in AGWSP were developed and validated with data from the pilot-scale
AGWSP experiments and some field-scale WSP.
Pond performances were evaluated with a simulation model based on
mass balance equations. The simulated results were more or less comparable
to the experimental data of AGWSP units, validating the beneficial effects
of AGWSP in wastewater treatment.
Since the attached-growth media are easy to maintain and do not
require as much skillful operation as that of the aquatic weed ponds,
their installation in WSP to improve the pond performance with respect
to organic and nutrient removal should be considered when necessary. |
| Year | 1987 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Environmental Engineering (EV) |
| Chairperson(s) | Chongrak Polprasert |
| Examination Committee(s) | Orth, H. ;Vigneswaran S. ;Wee, K. L. ;Hanaki, K. ;Middlebrook, E. J.
|
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 1987 |