Effect of powdered activated carbon type on the performance of an adsorption-microfiltration submerged hollow fiber membrane hybrid system

Abstract

This study highlights the importance of the type of powdered activated carbon (PAC) on the performance of an adsorption-MF hollow fiber membrane hybrid system. Submerged UF hollow fiber membrane with pore size of 0.4 Μm was used along with the PAC in a single reaction tank to treat the wastewater. This procedure is different from the commonly adopted practice of having adsorption with PAC as a pretreatment step to membrane operation. This system is helpful in containing the PAC within one system, allows certain variation in feed characteristics and improves the efficiency of the hybrid system. The overall performance of the membrane hybrid system was evaluated based on TOC removal, UV254 absorbance, turbidity removal and flux development. It is important to select a right PAC type to be used in the hybrid system in order to minimize the PAC dose and to enhance the performance. The adsorption capacity of the activated carbon had a greater influence on the overall performance of the hybrid system than other physical properties of the PACs and must be given greater consideration when selecting the PAC for the membrane hybrid system. Scanning electron micrograph (SEM) analysis of the cake deposit over the membrane helps to support the reason for moderate retention of organics.