| Author | Yau, Chap Hoi |
| Call Number | AIT Thesis no. 643 |
| Subject(s) | Water--Pollution
Oxidation
|
| Note | A thesis submitted in partial fulfillment of the requirements
for the degree of Master of Science of the Asian Institute of
Technology, Bangkok, Thailand. |
| Publisher | Asian Institute of Technology |
| Abstract | A pilot scale oxidation ditch was built to evaluate whether the
design parameters recommended by PASVEER (1969) could be improved
under tropical conditions. While nutrient and D.O. were maintained at non-limiting levels, 8 different organic loadings of Pepsi-Cola waste, ranging from F/M = 0.07 to 0.78, were studied at a common
detention time of 48 hours. Results showed that the effluent COD, increased with increasing loading. But the COD removal efficiency remained above 96% throughout the whole organic loading range. Ash content of the sludge was about 24% at loadings below F/M = 0.2, but
decreased down to 13% at higher organic loadings.
Keeping the organic loading with F/M about 0.38, the results.
of 3 tests with different detention times showed that the change of hydraulic retention time from 48 hours to 17.5 hours did not change the COD removal rate, nor. the ash content of the sludge. However, at the same organic loading, a low influent COD lowered effluent COD
and SVI . In a separate test, laboratory scale aeration units were set up to find out the chemicals which can restore the settling properties of a bulking sludge, once it occurs in an oxidation ditch, by changing its microbial composition. It was found that addition of calcium
acetate at a concentration of 0.6 g per litre of bulked sludge, with
NaN03 at a concentration of 0.5 g per litre of bulked sludge, suppressed the growth of Sphaerotilus, and selectively promoted to growth of other desirable bacteria so that the bulking problem was completely
eliminated in a period of 8 days. |
| Year | 1974 |
| Type | Thesis |
| School | Student Research Before 1980 |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Thesis (Year <=1979) |
| Chairperson(s) | Pescod, M.B. ; Yang, Yi Ping |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1974 |
