| Author | Pradhan, Nabin |
| Call Number | AIT Thesis no. EV-98-8 |
| Subject(s) | Water--Purification--Manganese removal
|
| 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 carried out to study the pretreatment process for manganese removal
from raw water and assess its effect on membrane fouling. Manganese is considered to cause
aesthetic problems such as colored water, turbidity, staining and taste. It has also been found
that manganese was major cause of membrane fouling. The study was aimed towards
biological pretreatment for manganese removal. The fluidized bed pretreatment reactor
containing tubular polypropylene pellets was, therefore, seeded with the slimes considered to
contain manganese oxidizing bacteria and no chemical oxidant was added. Laboratory scale
dead end microfiltration process was carried out under constant flux of 0.50 mid. Prefiltered
tap water augmented with manganese, potassium dihydrogen phosphate, and ammonium
chloride was used as feed water.
Duration of forty days was required for startup of pretreatment reactor with media and
was efficient in removing manganese after the color of media changed to black due to coating
of insoluble oxides of manganese. The media was effective in adsorption and oxidation of
manganese even without the aid of chemical oxidant. More than 95 percent of manganese
was biologically or chemically removed in fluidized bed pretreatment. Trans-membrane
pressure increased very slowly in the beginning of the experiment in the membrane filtering
pretreated water. Later when the membrane color changed to dark brown, TMP increased at a
rapid rate. Resistance exhibited by both membranes filtering water with and without
pretreatment was not of difference. Manganese was found to be major cause of membrane
fouling, however, the ratio of attached iron and manganese was factor behind membrane
resistance. Lower ratio of attached iron and manganese demonstrated higher resistance. |
| Year | 1998 |
| 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) | Takizawa, Satoshi; |
| Examination Committee(s) | Ozaki, Hiroaki ;Ha, Sung-Ryong; |
| Scholarship Donor(s) | DAAD (Federal Republic of Germany) ; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1998 |