Current World Environment

5-day BOD and COD can be removed by biological aerobic treatment of saline wastewater. In this research, halophilic microorganisms, namely Aspergillus oryzae and Halobacillus dabanensis were isolated from a return sludge basin of a  wastewater treatment plant in the City of Bandar Abbas  in southern Iran , that contained  a Total Dissolved  Solid (TDS) of about 7500 mg l^-1. These microorganisms (bacteria and fungi) could tolerate 20% concentration of salt (NaCl) in Sabouraud-4% dextrose agar and Sabouraud-2% dextrose broth medium and brain heart (BHI) agar and BHI broth medium. The films of Aspergillus oryzae and Halobacillus dabanensis were formed around the Ca-alginate. These bioflims were introduced to a fixed bed column, on top of which saline wastewater was released with flow rates of 2-6 ml min^-1. According to the results of Stover-Kincannon model, the constant values of maximum BOD and COD were estimated at 0.066 mg BOD₅ l^-1min^-1 and 0.1449 mg COD l^-1 min^-1, respectively. The saturation constant values, at the flow rate of 2ml min^-1, by Aspegillus oryzae were 0.00003 mg BOD₅ l^-1min^-1 and 0.00038 mg COD l^-1min^-1. The removal process in fixed bed column was stopped after 1200 minutes.