| Author | Bandulahewa, Ranjani |
| Call Number | AIT Thesis no. EV- 90-29 |
| Subject(s) | Sewage--Purification--Filtration
|
| Note | A thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | Mobile Bed Filters (MBF) have been used since 1960 ' s mainly for the
treatment of industrial processing water. However information on the
design parameters and optional characteristics are lacking. In MBF, the
most important operations are sand recycling and sand washing which
determines the removal efficiencies.
In the MBF arrangements used in past researches, no details on sand
washing and sludge removal were given. Also the removal efficiency was
not sufficient and not much literature was available on its performance
with contact flocculation-filtration arrangement in tertiary wastewater
treatment, especially on dissolved COD, N, P removal in view of water
reuse. Results obtained from the laboratary-scale MBF unit with contact
flocculation-filtration arrangement with kaolin clay suspension indicated
that suitable sand recycle rate and sludge withdrawal rates were 190ml/min
and 160ml/min respectively. The upflow mode avoided leakage of turbidity.
Experiments carried out with AIT oxidation pond effluent mixed with
AIT sewage, to test the applicability of MBF in producing water of reuse
quality indicated that MBF with contact flocculation filtration
arrangement was good in removing COD, T-P and turbidity with no headloss
development. The N and dissolved COD removal were not significant to meet
the reuse water quality. Therefore post treatments such as zeolite ion
exchange and activated carbon adsorption had to be used to treat the TKN
and dissolved COD respectively in the effluent of MBF.
These experiments showed that the MBF can be used to treat secondary
effluent with or without post treatment depending on the requirements of
water reuse . Taking into account the results of this study a design of
pilot scale MBF unit was made to treat wastewater of 200 l/d capacity. |
| Year | 1990 |
| 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) | Vigneswaran, Saravanamuthu
|
| Examination Committee(s) | Mino, Takashi ;Tran, Francis T.
|
| Scholarship Donor(s) | "Women in Development Fund,Canadian
International Development Agency, Canadian
High Commission, Colombo, Sri Lanka" |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 1990 |