| Author | Kanchit Wongsaengchantra |
| Call Number | AIT Thesis no.EV-93-29 |
| Subject(s) | Sewage--Purification--Activated sludge process
|
| Note | A thesis s ubmitt ed in partial fulfillment of the requirements
for the degree of Master of Science |
| Publisher | Asian Institute of Technology |
| Abstract | Two batch and one continuous laboratory scale reactors of
anaerobic-oxic activated sludge process were carried out to treat
modified tapioca starch wastewater. The batch reactors #1 and #2
were operated at different Food/Microorganism (F/M) ratio ranging
from 0.2 - 0.7 and 0.3 - 1.0, respectively. While the continuous
reactor was operated with F/M ranging from 0.3-1.0.
The batch reactors achieved around 90% COD removal efficiency.
However when chemica1 pretreatment was app1ied, the COD removal
efficiency increased to around 92%. The SVI values obtained from
those batch studies were ranging from 47-180 ml/g which indicated
good sludge settleability. Although the microscopic observations
showed the existence of short filamentous microorganism in the
batch reactors it did not affect the settleability of sludge.
Further, the continuous reactor yielded an average COD removal
efficiency of 93% which was higher than that of batch reactors. In
this study very good sludge settleability was also obtained which
was evidenced by the SVI values ranging from 40-120 mL /g. The
microscopic observations did not show existence of any filamentous
microorganism in the reactor. However, the effluent quality
obtained from this study in terms of COD was around 150 mg/L, which
was higher than the normally expected value of around 100 mg/L.
Therefore a series of studies were carried out to reduce the COD
value to lower than 100 mg/L. Powdered activated carbon dose of 1g
for 1L of effluent with a contact time of 1 hr. produced a final
effluent having COD value less than 100 mg/L. |
| Year | 1993 |
| 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) | Samorn Muttamara; |
| Examination Committee(s) | Tanaka, Shuzo;Sompol Boonthanon; |
| Scholarship Donor(s) | Government of New Zealand; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1993 |