Applying response surface methodology on the results of serial sequencing batch moving bed reactor

Abstract

This study introduces the new biological reactor that called serial sequencing batch moving bed reactor. In this research, this reactor was used for treatment of hospital wastewater. Furthermore, three independent variables (retention time, pollutant loading and media filling percentage) were investigated. For the first time, modeling of COD removal percentage (as the dependent variable) in hospital wastewater treatment was investigated by using of response surface methodology. According to the results, the COD removal efficiency increased from 58 to 91%, when pollutant loading decreased from 0.38 to 0.3 kgCOD/kgMLSS. Also, COD removal efficiency increased from 38 to 86% when retention time increased from 16.48 to 58.52 h. According to the results, the media filling percentage had the minimum effect on the COD removal efficiency, so that, COD removal efficiency increased from 63 to 78% with increasing in media filling percentage from 19.77 to 45%. The results revealed that the optimum condition to achieving the highest COD removal efficiency was at the retention time of 46.59 h, pollutant loading of 0.34 kgCOD/kgMLSS and media filling percentage of 42.24%. According to this research results, this reactor have high efficiency in hospital wastewater treatment.