Mass transfer kinetics of chemical oxygen demand removed from palm oil mill effluent in stirred cylinder batch reactor.

Abstract

Understanding the mechanisms and mass transfer kinetics of chemical oxygen demand (COD) removed from palm oil mill effluent (POME) could be one of the most important steps to achieve an effective design process of engineering acetogenic bacteria. The aim of this study was to evaluate the mass transfer kinetics of COD removed from POME in stirred cylinder batch reactor (SCBR) under an anaerobic environment using the modified mass transfer factor models. The performance of SCBR for the removal of COD increased with an electromagnetic field (EMF) exposure reaches 77.6% of its maximum efficiency when the operation of SCBR was set at the hydraulic retention time of 9 days. The variation of [kLa]d value has a trend of almost similar to that of [kLa]g value and is far higher than that of [kLa]f value to conclude that the resistance of mass transfer for the removal of COD from POME by the SCBR process depends on external mass transfer. The analysis of COD removal efficiency pursuant to the [kLa]d value provides a new insight on the performance of SCBR increased with an EMF exposure contributing to advanced treatment of COD from POME for achieving an effective process of engineering acetogenic bacteria.