Pfas Adsorbent Selection: The Role of Adsorbent Use Rate, Water Quality, and Cost

Characterizing PFAS concentrations in drinking water treatment residuals

“…In some treatment scenarios where PFAS breakthrough and adsorbent PFAS loading are achieved in a similar timeframe, utilities may even go so far as to preemptively changeout their media based on spent adsorbent PFAS concentration in order to reduce disposal costs associated with more restrictive disposal requirements. Concentrations of PFAS on adsorbent materials will vary as a function adsorption effectiveness which can be attributed to differences in influent PFAS concentration, operating conditions, changeout thresholds, and concentrations of other competing adsorbates (Boyer et al, 2021; Murray et al, 2021, 2023; Park et al, 2020; Tajdini et al, 2023; Vatankhah et al, 2022). PFAS concentration factors in membrane concentrate were much lower than those predicted for spent absorbent materials.…”

“…PFAS are composed of highly stable C‐F bonds that contribute to their widespread use by commercial and industrial users and also makes these chemicals highly recalcitrant to conventional drinking water treatment processes and disinfection (Appleman et al, 2014; Crone et al, 2019; Gagliano et al, 2020; Rahman et al, 2014; Zhong et al, 2023). Effective PFAS removal from drinking water requires advanced treatment technologies such as granular activated carbon (GAC), ion exchange (IX), and high‐pressure membrane filtration (Ellis et al, 2022; Franke et al, 2019; Liu et al, 2022; Liu, McKay, et al, 2021; Murray et al, 2021, 2023). These processes are capable of achieving upward of 90 to 99 percent removal of certain PFAS (e.g., PFOA and PFOS), whereas conventional processes have typically not provided more than 10 to 15 percent removal of PFAS (Appleman et al, 2014; Xiao et al, 2013).…”

“…These processes are capable of achieving upward of 90 to 99 percent removal of certain PFAS (e.g., PFOA and PFOS), whereas conventional processes have typically not provided more than 10 to 15 percent removal of PFAS (Appleman et al, 2014; Xiao et al, 2013). Innovative technologies continue to be developed for PFAS removal including novel adsorbent materials (Medina et al, 2022; Murray et al, 2023; Najm et al, 2021) and enhanced coagulant aids (Cornelsen et al, 2021) that can facilitate the removal of PFAS. The newly proposed drinking water regulations for PFAS set forth by the EPA are expected to have a significant impact on DWTPs given the anticipated costs associated with the installation and operation of these advanced treatment technologies (Franke et al, 2019; Murray et al, 2021).…”