| Author | Giri, Rabindra Raj |
| Call Number | AIT Thesis no.EV-99-6 |
| 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 | This study was designed to examine the biological treatability of domestic wastewater in the
BMR. The use of septic tank has greatly influenced the wastewater characteristics in the
region. The mode of defecation, too, has significant effects in it.
Self-purification potentials in the tropical climates, effects of night soil contamination and
cellulose decomposition, and dilution effects in self-purification were taken as assessment
parameters. Laboratory scale batch experiments with domestic wastewater from the
representative residential area of the region were carried out at 30°C temperature in the
assessment.
The results of the study revealed the high biodegradable organic matter content in the
domestic wastewater and, thus, high potential for self-purification in tropical climates. The
dilution factor was found to play important role in self-purification. Numbers and diversity of
genera in microbial populations in activated sludge were highly influenced by night soil
contamination in wastewater. Septic tanks were found to reduce pathogenic microorganisms
and organic loads by 70 to 80%. Addition of cellulose in domestic wastewater was found to
increase organic load in wastewater. Increase in cellulose concentrations was observed to
inhibit the cellulolytic and other microbial activities. Many microbial communities of the
natural aquatic systems were inhibited in presence of night soil and the products of cellulose
decomposition. Consideration of self-purification in the design of treatment facilities and
modification of the conventional treatment facilities for low strength wastewater are more
important in the local conditions of the BMR. |
| Year | 1999 |
| 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) | Ozaki, Hiroaki; |
| Examination Committee(s) | Chongrak Polprasert ;Preeda Parkpian; |
| Scholarship Donor(s) | Government of Japan; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1999 |