Submerged aerated filters (SAFs), are used to meet stringent ammonium (NH4+) and soluble organic consents. Current design follows a black box approach, whereby inlet and outlet contaminant concentrations are monitored, independently of internal hydrodynamic conditions. To investigate the influence of internal hydrodynamic conditions tracer tests were performed on a SAF with biofilm on the media surface, at 100, 75, 50 and 25% media fill ratios. Results indicate that SAF internal hydrodynamic conditions directly influence process performance. A 50% media fill ratio showed optimum hydrodynamic conditions for BOD5 removal, with a removal efficiency of 70% and a mean tracer retention time (¯t), exceeding the hydraulic retention time (HRT) by 68 mins. A 100% media fill ratio showed optimum conditions for NH4+, with a removal efficiency of 60%, but internal shortcutting was evident. The methods used can be applied to diagnose, underperforming SAF reactors and enable optimisation of internal hydrodynamic conditions for selective contaminant removal.
|Number of pages||5|
|Publication status||Published - 30 Jun 2016|
|Event||3rd IWA Specialized International Conference 'Ecotechnologies for Wastewater Treatment' (ecoSTP16) - Cambridge, United Kingdom|
Duration: 27 Jun 2016 → 30 Jun 2016
|Conference||3rd IWA Specialized International Conference 'Ecotechnologies for Wastewater Treatment' (ecoSTP16)|
|Period||27/06/16 → 30/06/16|