| Popis: |
Biofringe (BF) carrier material creates swimming motion due to velocity of downflowwastewater, a characteristic of swim-bed technology, and provides a high degree ofsubstrate-biomass contact. In this study, BF fiber material was packed in a plug-flowactivated sludge reactor, to investigate its feasibility in improving the sludge settleabilityand enhancing the pollutant degradation performance of the activated sludge process.High SBOD5, SCOD, and ammonium removal efficiencies of 99.1%, 96.5% and 83.6%,respectively were obtained at volumetric loading rate of 4.5 kg-SCOD/m3/d. SVI valuesbelow 50 ml/g and high settling velocities demonstrated satisfactory settling characteristicsof the biomass, which were attributed to the increase in the size of the biomass flocs as aresult of use of BF carrier material. Relatively low viscosity of mixed liquor also facilitatedsludge settling performance as no sludge bulking problems were encountered throughoutthe experimental period. Existence of a large amount of protozoa and metazoa observedthrough microscopic examination was considered to contribute to the low sludge yieldcompared to conventional activated sludge. Microbial analysis demonstrated microbialcommunity shift between the seed sludge and the sludge sample after 378 days of operationwith proteobacteria to be predominant. The results demonstrated that use of swim-bedtechnology enhanced treatment performance and provided process stability to theconventional activated sludge process. |
