Formatted Title
Technologies for Effective Treatment of Ultra-Short Chain PFAS
Background/Objectives
Much of the published work to date has been on treating per- and polyfluoroalkyl substances (PFAS) compounds having 4 or more carbons. The performance of the treatment systems varies significantly when comparing ultra-short chain PFAS (C=2-3) to the longer chains (C>=4).
Approach/Activities
The objective of this study was to develop a system for effective treatment of PFAS, including ultra-short chains, and demonstrate the capability through pilot testing. The treatment system included a combination of ultrafiltration, reverse osmosis, granular activated carbon, and regenerable ion exchange media. The streams tested in the pilot system included groundwater, stormwater, and process wastewater to determine the effects of varying levels of non-PFAS constituents in the water.
Results/Lessons Learned
The results of the pilot study showed that the proposed configuration of treatment technologies can remove PFAS to below analytical limits of detection with starting concentrations in the parts per million range. Both reverse osmosis and ion exchange were effective at removing the ultra-short chain PFAS, however, the concentrations of non-PFAS anions in the water had a significant impact on the ion exchange removal efficiency. The amount of energy used in the process and the waste generated also varied based on the water quality and target concentrations. The successful regeneration of the ion exchange media was demonstrated in the pilot study using an alcohol and brine mixture, as well as the recovery of the alcohol through a distillation process.