| Author | Goel, Rajeev |
| Call Number | AIT Thesis no. EV-94-09 |
| Subject(s) | Sewage--Purification--Biological treatment
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of
Master of Engineering, School of Environment, Resources & Development |
| Publisher | Asian Institute of Technology |
| Abstract | This experimental study was undertaken on two type of anaerobic pilot scale reactors
installed in the premises of a synthetic fiber producing industry. Fixed bed and contact tank
reactors of size 3500 l each were used in the study. Contact tank reactor was started by
inoculating with sludge of septic tank origin. On the other hand, no seeding was used for the
fixed bed reactor as it contained sludge because of its previous operation in treating
slaughter house wastewater.
Both, the reactors were operated under varying COD loading at different hydraulic
retention time (HRT). During the failure of the reactor under higher loading, an increase
in the concentration of propionic and butyric acid inside the reactors was observed. This is
contemplated to be the major cause of process upset. The maximum organic loading of 2.2
kg COD/m3 .d at HRT of 4.5 days for the fixed bed and 1.3 kg COD/m3 .d at HRT of 7.8
were achieved under stable conditions. Poor immobilization of biomass in the contact tank
as compared to the Fixed bed reactor was achieved and this resulted in difference in
maximum achievable organic loadings.
The batch activity tests are found to be an effective tool to assess the methanogenic
activity of the sludge and predicting the state of the reactor. But, inadequate methods of
assessing the biomass concentration inside the reactors are seen as a limitation.
Simplified process control strategies for detecting the process changes are defined
using major process parameters like COD loading, pH, Gas production rate and the
concentration of Volatile Fatty Acids. But, these are seen to be inadequate as the proper
control action are not defined to run the process optimally. An adaptive control strategy is
developed which can be computerized for on-line monitoring and control of anaerobic
processes for optimal operation. ยท' |
| Year | 1994 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Stoll, Uwe
; |
| Examination Committee(s) | Wise, Donald L. ;Fujii, Shigeo ; |
| Scholarship Donor(s) | Swedish International Development Authority (SIDA),
Sweden; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1994 |