Improvement of mixing patterns in pilot-scale anaerobic ponds treating domestic sewage.
Anaerobic ponds are customarily designed as completely mixed reactors. However, evidence from experiments on full-scale facilities shows large deviations from ideal flow models, which in turn cause a reduced process performance. Thus, modified pilot scale anaerobic ponds receiving domestic sewage were developed and studied in parallel. A factorially designed experiment evaluated horizontal and vertical baffling, ponds fitted with cross-sectional plastic nets and a pond with a mixing pit. The hydrodynamic behaviour and process performance of these modified configurations were monitored for four flow rates (1.0, 1.2, 1.5 and 2.0 l/s). The results showed that baffling (vertical and horizontal) and the mixing pit configuration had the best hydrodynamic behaviours and removal efficiencies. Consequently, the development of high-rate anaerobic ponds, through improvements of hydrodynamic behaviour, seems feasible.
D001421:Bacteria, Anaerobic / Q000502:physiology*; D019149:Bioreactors; D005160:Facility Design and Construction; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014872:Water Movements
D012722:Sewage