How to Plan for PFAS in Carbon-based Potable Reuse Implementation

PFAS are prime examples of how water recycling facilities can help break the circulation of these chemicals from the water cycle. Treatment technologies typically in use at WWTPs are ineffective for removing PFAS. While the most common technology for PFAS includes adsorptive, ion exchange, or RO membrane filtration processes, limited PFAS removal is expected across the ozone-biological activated carbon (Ozone-BAC) treatment steps within the carbon-based advanced treatment (CBAT) train. Granular Activated Carbon (GAC) is often included downstream of ozone-BAC for TOC removal. GAC provides reliable PFAS removal. However, utilizing a single GAC step for both TOC and PFAS removals may limit the full use of GAC adsorption capacity (i.e., PFAS breakthrough could occur ahead of TOC breakthrough). We will highlight our work on designing an advanced treatment train to achieve potable reuse standards, including an efficient approach for PFAS removal, and discuss the complexities of spent PFAS media management.