The Journal of

Introduction: Aerobic treatment processes with fixed growth has attracted attention of the engineers and designers of wastewater treatment due to the separation of organic materials in sewage and also to nitrification (conversion of ammonium to nitrate).The purpose of this study was to evaluate the performance of Submerged Biofilm Reactor to removal of organic matter (BOD and COD), turbidity and suspended solids (TSS) from wastewater of Farabi Hospital of Kermanshah. Methods:In this study, first it was attempted to build the reactor, to startup and to load the activated sludge fixed growth with bed submerged systems and then to evaluate efficiency of the system for removal of the organic materials( BOD, COD), turbidity and total suspended solids in three different retention times (2.9 h. aeration and 1.1 h. anaerobic, 3.6 h. aeration and 1.4 h. anaerobic, 4 h. aeration and 1.5 h. anaerobic), 135 samples were performed. Results:Results showed that the highest level of removal of COD, BOD, TSS and turbidity was in the Phase III of the system (4 h aeration and 1.5 h anaerobic) so that the percentage of removal average of the mentioned parameters were 82, 95, 98.4 and 98% respectively. Also comparison of removal efficiency of these parameters showed no significant differences (except BOD and turbidity). Conclusion:According to the results, by proper operation and maintenance, the Submerged Biofilm Reactor has high performance in COD, BOD, TSS and turbidity removal from hospital wastewater, without the need for biological solids to be returned