Formatted Title
Foam Fractionation and On-Site Destruction Technologies to Meet MCLs
Background/Objectives
Foam fractionation has emerged as a promising PFAS treatment alternative to traditional adsorption media-based systems. Previous studies have shown 98-100% removal of regulated PFAS using SAFF® alone, meeting proposed EPA drinking water standards. Nevertheless, improvements to foaming characteristics, volumetric concentration, and PFAS removal may be gained from using co-foaming additives, which may be tailored for site-specific solutions. Through a variety of laboratory and full-scale treatment projects, recent advancements have furthered understanding of the potential of this technology with respect to treatment of short-chain compounds and the importance of optimizing operations based on influent water foaming characteristics. This presentation will share recent data relating to advancements in use of additives to improve the foam fractionation process, and discuss the costs and benefits of using additives in the foam fractionation process.
Approach/Activities
Multiple case studies will be presented that focus on application of Surface Active Foam Fractionation (SAFF®) for “closed-loop” treatment train design, where removed target compounds from groundwater are destroyed using on-site PFAS destruction treatment processes. The case studies will include both groundwater treatment and treatment of landfill leachate. SAFF® may be paired with a variety of destruction technologies such as plasma vortex, hydrothermal alkaline treatment, electrochemical oxidation, or supercritical water oxidation to enable a low-footprint and fully on-site PFAS treatment solution. SAFF® is an engineered system that separates and concentrates PFAS from water into a liquid waste without adsorption media over a series of foam fractionation stages. Instead of using solid media to adsorb PFAS, SAFF® takes advantage of the surfactant properties of PFAS compounds, which naturally adsorb to bubble surfaces and can be captured and dewatered as a foam concentrate. The case studies will illustrate that foaming characteristics of PFAS-contaminated water vary widely, and that site-specific optimization, including co-foaming additives, can be used to meet even the most stringent discharge criteria.
Results/Lessons Learned
Data and project outcomes will demonstrate that three primary objectives have been achieved: 1) full separation and concentration of regulated PFAS from contaminated water using advanced additives to meet the draft EPA maximum contaminant levels for drinking water, 2) destruction of PFAS liquid concentrate sufficient to facilitate closed loop, on-site operation, and 3) cost-effective and sustainable separation, concentration, and destruction relative to alternative on-site separation technologies (e.g., carbon adsorption using granular activated carbon or ion exchange resin).