Effect of the hydraulic detention time and the volumetric ratio of anaerobic to aerobic zone on the efficiency of the upgraded activated sludge units using (Bardenpho) system


In this research, five experimental plants have been established and operated usingsynthetic domestic wastewater in order to study the effect of some operationalparameters on the removal efficiency of organic and nutrients pollutants in BardenphoProcess. The results of the research proved that the removal efficiency of organic,nitrogen, and phosphorus materials were higher in the reactors that work by Bardenphoprocess comparing to the ordinary activated sludge system. Also the biological sludgeresulted from Bardenpho reactors has better settling characteristics. Likewise, the pHvalues in the plants work by Bardenpho process were lower than those in the plant thatwork by ordinary activated sludge system. The results of the study also shown that theremoval efficiency of organic materials in the Bardenpho reactors increases by thereduction of volumetric ratio of the anaerobic to aerobic zone, in contrast, theconcentrations of Nitrate, Ammonia, and Phosphate decrease by the reduction this ratio,in addition, the value of SVI decreases by increasing the size of anaerobic zone. On theother hand, The results also proved that increasing the hydraulic detention time (HRT)lead to increase the efficiency of removing organic, nitrogen, and phosphorus materialsof the biological reactors that work by Bardenpho process. Moreover, increasing theHRT leads to increase value of the sludge volume index (SVI) at all of the Bardenphoand ordinary activated sludge reactors. In contrast, the value of pH drops by theincreasing of hydraulic detention time.