Operational strategy for septage dewatering in constructed wetlands | |
| Author | Rungrod Jittawattanarat |
| Call Number | AIT Thesis no. EV-98-15 |
| Subject(s) | Constructed wetlands Sewage sludge digestion |
| 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 | This study aimed to determine the sludge dewatering and treating efficiencies of vertical flow constructed wetlands treating septage. Three pilot-scale constructed wetland units planting with narrow-leave cattails (Typha augustifolia) were setup. Septage samples from Bangkok Metropolitan Administration (BMA) used as feed. The following operational strategies: solid loading rate (SLR) , frequency of loading, percolate retention period were investigated. Base on the 8 months experiments it was found that; the SLR in the range of 80-250 kgTS/m2 .yr did not have significant effects on the removal efficiencies of TS, TVS, SS, VSS, NH3-N, TKN and TCOD concentrations. The high SLR results in reduced NH3-N removal efficiency probably because anoxic conditions. The twice-a-week loading had some beneficial effects on plants growth, but not on the TCOD and solid removal. Higher NH3-N and TKN removal could be achieved with the 2-days percolate retention period in the constructed wetland beds, but the highest overall N removal were achieved at the 6-days percolate retention period. The sludge volume reduction in the constructed wetlands were 96%-99%. The dried sludge on the constructed wetlands were 38%-52% of the total solids loading. Based on the experimental results obtained, the suitable operational strategy was found to be: SLR of 250 kgTS/m2 .yr, frequency of septage loading once-a-week and percolate retention period of 6 days. |
| 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 and Management (EV) |
| Chairperson(s) | Chongrak Polprasert |
| Examination Committee(s) | Annachhatre, Ajit P. ;Eckhardt, Heinz |
| Scholarship Donor(s) | Queen Sirikit's Scholarship for the Asian Environmental Development Program |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1998 |