Effect of increasing organic loading rate on the performance of conventional and modified sequencing batch reactors. (Dept. C)

Abstract
A modified sequencing batch reactor (MSBR) was developed by installing six fiber vertical plates of specific surface area of 180 cm2/ L in conventional sequencing batch reactor (SBR), which designed for supporting the biofilm formation and increasing the system efficiency. In this study, the effect of increasing the organic loading rate of 281.25 g COD/m3. d by 33%, 67%, and 100 % on the performance of SBR and MSBR was investigated. The effluent BOD5, COD and TSS of the MSBR at high organic loading rate was 20, 32 and 27 mg /L, respectively, while for conventional SBR was 34, 58 and 45 mg /L, respectively. The total bio-sludge of MSBR was more than that of conventional SBR by about 30% resulting in a reduction of the F/M value. The sludge volume index (SVI) in MSBR was lower than that of conventional SBR by about 33%. MSBR system was able to treat municipal wastewater with high performance.