Fresenius Environmental Bulletin, cilt.9, ss.297-305, 2000 (SCI-Expanded)
As organic matter content of the wastewater is limiting factor for phosphorus removal in enhanced biological phosphorus removal processes, avoiding available organic matter consumption, particularly volatile fatty acids by the denitrifiers as much as possible, and saving this amount for phosphorus removal gives rise to higher levels of phosphorus removals. In order to save that organic matter as much as possible and utilize this amount in biological phosphorus removal in any activated sludge treatment plant embedding nitrification, the most appropriate process option seemed the modification of A/O biological phosphorus removal process option. For this purpose, A/O was modified by adding an anoxic stage to the beginning of the process to remove only the recycled nitrate-nitrogens and resulting phosphorus removals over per unit of TBOD removal at different operational parameters were studied on a pilot scale plant operated on continuous-flow basis.