| Author | Soraya Pholkerd |
| Call Number | AIT Thesis no. EV-97-41 |
| Subject(s) | Constructed wetlands
|
| 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 |
| Series Statement | Thesis ; no. EV-97-41 |
| Abstract | The performance of constructed wetlands in the removal of pathogenic indicators, especially
the viral indicators (bacteriophages) and the bacterial indicators (fecal coliforms and fecal
streptococci) was evaluated. Four laboratory-scale and one pilot-scale free-water surface
(FWS) constructed wetland units were used to evaluate the kinetic coefficients of
bacteriophages, fecal coliforms and fecal streptococci die-offs into the wetland beds. The
emergent plants, cattails (Typha), were planted in the constructed wetland units.
The experimental results indicated that the organic loading rate (OLR) of 50 kgCOD/(ha.day)
and the HR.Ts of 0.5-5 days resulted in the bacteriophage removal of 57-94%, while fecal
coliform and fecal streptococci removal ranged from 60 to 97%. Under these conditions, the
BOD5 removal was 47-74%, while the COD and SS removal efficiencies were 33-60% and 71-
96%, respectively. TKN and Total-P removal were 25-65% and 16-34%, respectively.
The removal efficiencies of bacteriophage, fecal coliform and fecal streptococci during the
post-harvesting periods were found to be better than tho~e during the pre-harvesting periods
because of more sunlight exposure to the wetland beds during the post-harvesting periods.
With respect to the kinetic studies, the k20 of the bacteriophage were 0.13 day" 1 for the preharvesting and post-harvesting periods. However, for the fecal coliform and fecal streptococci,
the k20 was found to be 0.16 and 0.18 da/ during the pre-harvesting and post-harvesting
periods, respectively. |
| Year | 1997 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. EV-97-41 |
| 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) | Chongrak Polprasert |
| Examination Committee(s) | Ishibashi, Yoshinobu;Samorn Muttamara |
| Scholarship Donor(s) | Danish International Development Assistance (DANIDA) |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1997 |