Evaluation of Ozone to Enable Multi-Barrier Treatment for Potable Reuse

Water resources in many areas around the US and the world are strained. Water reuse is a growing and necessary component of integrated water resource management to ensure adequate supply of water for industrial, agricultural, commercial, and residential use.This paper discusses the results of a one year bench- and pilot-scale study to evaluate several different treatment train configurations applicable for indirect potable reuse (IPR) and direct potable reuse (DPR) with special emphasis on the use of ozone to enable multi-barrier treatment. The treatability testing is part of a collaborative research project, WRRF 11-02: Equivalency of Advanced Treatment Trains for Potable Reuse.Results indicate that ozone is a robust treatment barrier for pathogens and trace organic contaminants. The results show that the use of biologically active carbon after ozone (O3-BAC) can significantly reduce both total organic carbon (TOC) and NDMA while simultaneously removing trace organic contaminants and oxidation by-products.