ADVANCED BIOLOGICAL TREATMENT OF WASTEWATER USING A REACTOR WITH POLYETHYLENE TAPE

Abstract

The performance of an aerobic submerged packed bed reactor with polyethylene tape was studied for the treatment of domestic wastewater. The packing material had 1098 m2/m3 specific area. Three different zones were conformed within the reactor: anaerobic, anoxic and aerobic. The system was operated with 4 different organic loads. The objective of this study was to determine the simultaneous removal of COD, nitrogen and phosphorus and the best operational conditions for the system. The following parameters were analyzed and measured: COD, TN, NH4+-N, TP, TSS, VSS,. The duration of the experimental work was 308 days. The best average removal of COD (61%) and TP (39%) was obtained with an organic load of 4.73 kgCOD·m-3·d-1, HRT of 1.35 hours. It was observed that TP removal rates increased with the rise of the TP and organic loads. The best ammonia and TN removals, 71% and 66% respectively, were obtained when a load of 1.27 kgDQO·m-3·d–1 was applied, with 2.4 hours HRT and 100% recycling. There were not any clogging problems in the packed bed during all the operation period, thus backwashing procedures were not required. Based on the obtained results, it can be concluded that the aerobic submerged packed bed reactor with polyethylene tape allowed higher micronutrient removals than the conventional wastewater treatment systems, been in addition a novel system of easy operation.

Key words: Biofilter, C, N y P removal, polyethylene tape.