Importance of the order in enhancing EfOM removal by combination of BAC and MIEX^®

Biological activated carbon (BAC) is operationally a simple treatment which can be employed to remove effluent organic matter (EfOM) from secondary wastewater effluent (SWWE). Unfortunately, BAC removes only a limited amount of dissolved organic carbon (DOC). Thus, maximizing DOC removal from SWWE using BAC is a major concern in wastewater reuse. This study has investigated a hybrid system of BAC and Magnetic Ion Exchange Resin (MIEX^®) for the enhanced removal of DOC. Performance of both BAC prior to MIEX^® (BAC/MIEX^®) and reverse (MIEX^®/BAC) combination was evaluated in terms of DOC removal. The BAC/MIEX^® showed much better DOC removal. This is because microbial activity in the BAC bed converted MIEX^® non-amenable DOC to MIEX^® amenable DOC. As a result, BAC/MIEX^® combination synergised DOC removal. In addition, BAC was also found to be highly effective in reducing MIEX^® dose for a given DOC removal from SWWE.