Isolation and Identification of Dominate Bacteria in MBBR for ‎Hospital Wastewater ‎Treatment

Background and Aims: Identification of microorganisms is an important step in designing and operation of wastewater ‎treatment systems including MBBR system. This study aimed to identify and separating the bacteria ‎forming the biofilm used on the bed of MBBR system in hospital wastewater treatment.‎ Materials and Methods: This experimental study was carried out on a pilot scale of Besat Hospital real wastewater. A ‎volume of 100 liters of pilot plant was made of Plexiglas and the Kaldnes bed was used in this ‎study. After the formation of biofilm and microorganisms isolation from the bed firstly, gram and ‎special stain spores coloring was applied and then routine biochemical tests of microbiology of ‎dominant bacteria in the biofilm on the Kaldnes bed had been identified.‎ Results: Bacteria that had been identified in this study included:‎E.coli, Enterobacter spp, Bacillus spp, Alcaligenes spp, Proteus spp, Acinetobacter spp, and ‎Pseudomonas spp.The dominant bacteria found in this study were E.coli, Enterobacter spp, Bacillus ‎spp.‎ Conclusion: According to the results of this study, all bacteria identified and isolated from biofilm on the bed ‎are effective on removing organic materials from hospital wastewater‏.‏