Modeling and process evaluation of membrane bioreactor for removing biodegradable organic matter from water

Abstract

A membrane bioreactor (MBR) process was employed for removing biodegradable organic matter (BOM) and ozonation disinfection byproducts (DBPs) exemplified by total aldehydes from ozonated potable water. The BOM removal was to prevent or reduce microbial regrowth in water distribution systems and to reduce DBP forming potential after ozonation. A mathematical modeling approach was used as a tool for performance prediction and process design with implication to process upscaling. The modeling protocol integrated adsorption and biodegradation in liquid and adsorbent phases with model parameters obtained from independent experiments. The BOM was expressed as biodegradable dissolved organic carbon (BDOC), assimilable organic carbon (AOC), and total aldehydes. The MBR studies demonstrated the process effectiveness in removing AOC, BDOC and total aldehydes, and validated the model's predictive capability. Sensitivity studies qualitatively evaluated parameters influencing process dynamics. The simulation studies were unique in examining shutdown and startup effects on process dynamics and process recovery.