Environmental Assessment of Various End‐of‐Life Pathways for Treating Per‐ and Polyfluoroalkyl Substances in Spent Fire‐Extinguishing Waters

Abstract

Per-and polyfluoroalkyl substances (PFAS) are now thought to be far more prevalent in water bodies across the globe than previously reported. In particular, military bases, airports, and industrial sites are prone to contamination caused by runoff discharges from fire-extinguishing waters that contain PFAS such as aqueous film-forming foams (AFFF). These substances and their metabolites show a high degree of mobility as well as a low biotic and abiotic degradability; as a result, they are bioaccumulative and often migrate among the environmental compartments in addition to being toxic. As of now, there is no suitable end-of-life treatment process that is both technologically efficient and cost-effective for the handling of PFAS. Currently, the incineration of the collected extinguishing water at temperatures above 1100°C is the recommended method for the disposal of PFAS to degrade material compounds. However, this method consumes extensive energy because it requires incineration of large quantities of water to treat a diluted fraction of PFAS. Aside from incineration, adsorption of PFAS on granulated activated carbon is one of the most widely used technologies, albeit with poor adsorption and often requiring very large downstream filtration systems. Finally, the application of functional precipitation agents using commercially available cationic surfactants is a novel approach (PerfluorAd ® [Cornelsen] process) that enables the effective precipitation of PFAS from the spent fire-extinguishing waters. Hence, the goal of the present study was to investigate the environmental impacts emanating from the proper treatment of spent fire-extinguishing water with the aforementioned 3 end-of-life treatment scenarios. A life cycle assessment was conducted for this purpose. The results show that the PerfluorAd process outperforms the other 2 treatment technologies across all environmental impact categories except for ozone depletion.

Legacy and Emerging Per- and Polyfluoroalkyl Substances: Analytical Techniques, Environmental Fate, and Health Effects

“…This sludge, however, is eventually removed from the WWTP and is often used as organic soil amendment which has been shown to contribute to the contamination of soil and agricultural crops [52]. Sewage sludge, AFFFs, textiles, and other PFAS-containing products are also routinely disposed of at incineration facilities [53][54][55][56]. It is unclear whether PFAS are released to the atmosphere in their original state during incineration; however, the release of lower-molecular-mass PFAS products has been reported [56].…”

Nothing lasts forever: understanding microbial biodegradation of polyfluorinated compounds and perfluorinated alkyl substances

“…Carbon filtration is known to remove many organic contaminants, often present at higher concentration than the fluorinated compounds, resulting in competition for binding sites on the adsorbent. For this reason, there have been accelerated efforts to produce more specific adsorbents, and new companies have emerged from these technologies (Ching et al ., 2020 ; Maga et al ., 2021 ).…”

PFAS fate and destruction mechanisms during thermal treatment: a comprehensive review

“…Per- and polyfluoroalkyl substances (PFAS) are a family of synthetic organic chemicals manufactured and widely used in a variety of industries and consumer products around the globe since they were first developed in the 1940s. Due to their unique physical and chemical properties that include water and oil repellency, heat resistance, strong surfactant properties, 1 PFAS are popular in a large variety of applications from food packaging, cosmetics, commercial household products, fire extinguishers, and industrial applications. Due to their persistence in the environment and association with great potential risks to ecosystems and human health, there is increasing concern over the detection of PFAS throughout the environment, including soil, surface water, groundwater, sewage sludge, and landfilled leachate.…”

“…The recommended method of disposal of PFAS-containing fire extinguishing water from using AFFF is incineration at high temperature (over 1100 °C). 1 However, this method is not energy efficient considering it incinerates a considerable volume of water for a diluted fraction of PFAS in the AFFF. 1 For PFAS-contaminated water, the current state of practice of thermal treatment generally involves two steps.…”

“…1 However, this method is not energy efficient considering it incinerates a considerable volume of water for a diluted fraction of PFAS in the AFFF. 1 For PFAS-contaminated water, the current state of practice of thermal treatment generally involves two steps. The first step is to concentrate PFAS; the second step is to use reverse osmosis, ion-exchange resins, or GAC to trap PFAS.…”