SBAR Capability for Methyl Tertiary Butyl Ether Removal: Characterization of the Bio-granules

The growing use of MTBE as a substitute for Tetraethyl lead and its adverse impacts on the environment warrant its removal from wastewater. Given the low efficiencty and the high cost associated with the chemical and physical processess commonly used for the removal of MTBE, which also release hazardous by-products into the environment, biological techniques have been explored as the more appropriate methods for its removal. This research seeks to investigate the feasibility of the SBAR system and aerobic biogranules for MTBE removal. For this purpose, a synthetic wastewater containing the materials needed for the microorganisms was used for the experiments and the pH level and DO were set to 7‒8 and 2‒5 mg/L, respectively. TEM was employed to characterize the granules. Results showed that over 90% of the initial COD (500 mg/L) was removed after 4h, which was attributed to the air stripping (28%) and sorption (1.5%) mechanisms. The resulting granules were brown in color, 2‒6 mm in size with a mean fall speed and a density equal to 0.65 cm/s and 0.055 g/ml, respectively. The superiority of the resulting granules to the flocs led to improved sedimentation in the reactor. Finally, TEM investigations showed that the sylyath and rotifer species formed the dominant populations in the granules.