| Author | Daniel, Vetha Anbu Selvam |
| Call Number | AIT Thesis no. EV-98-12 |
| Subject(s) | Water--Purification--Membrane filtration
|
| 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 | Biological fouling in membrane filtration is rated as one of the ยท above average
problems encountered in filtration units used for drinking water treatment. This research has
considered the effect of fouling by two microbial species namely, Staphylococus aureus
subsp. aureus (Yl) and Microbacterium sp (Y4), commonly occurring in feed waters used in
drinking water treatment plants. The effects of these species on the operating parameters of
Cellulose Acetate and PVDF membranes were studied in detail.
The research indicates that resistance offered by initial attachment of both species on
Cellulose Acetate membranes is higher than PVDF membranes. Resistance offered by initial
attachment of floe bacteria like Yl is less than Y4 species. While in the case of biofilm
attachment PVDF membranes is generally found to have higher resistance than Cellulose
Acetate membranes. Initial attachment of Yl species is difficult to remove than Y 4 species by
physical methods, namely by backwashing and hydrodynamic shear in both membranes.
While on the contrary, when Yl species form biofilms, their removal was easier than Y4
species by physical methods. Reduction of cake resistance formed by initial attachment of
both Yl and Y4 species was generally easy to reduce in Cellulose Acetate membrane than
PVDF membranes by these physical methods. In the case of biofilm attachment, it was found
that generally, biofilm resistance on PVDF is easier to reduce than Cellulose Acetate
membranes. In the case of chemical cleaning by chlorine it was observed in this experiment,
for both initial and biofilm attachment, percentage reduction of resistance is greater for Y 4
species than Yl species. It was also further observed that chlorine concentration of 50 to 100
ppm can achieve considerably high percentage reduction of resistance.
These phenomenon are attributed to the inherent characteristics of the species and the
intrinsic properties of these membranes to interact with these species. The research indicates
the effects of floe and non-floe forming bacterium on Cellulose Acetate and PVDF
membranes. |
| 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 ;Rakshit, S. K. |
| Scholarship Donor(s) | Asian Institute of Technology (AIT)
Institute for Integrated Rural Development (IIRD) |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1998 |