Disposal of Aqueous Film-Forming Foam using Hydrodynamic Cavitation

The widespread use of Aqueous Film Forming Foams (AFFF) at DOD facilities for firefighting, training, and fire suppression systems has resulted in numerous contamination sites. The perfluoroalkyl (PFA) compounds used in the AFFF, such as perfluoroalkyl sulfonates (PFOS) and perfluoroalkyl carboxylic acids (PFOA) are extremely stable in the environment and have been shown to be resistant to typical biological and chemical degradation processes. However, laboratory studies have shown that PFA can be pyrolyzed using cavitation.In this Phase I STTR we will investigate the feasibility of using hydrodynamic cavitation under ambient and sub-critical conditions to thermally degrade PFA solutions. The use of cavitation will allow us to take advantage of sub-critical water properties and to perform pyrolysis of APFF under much milder conditions (150 C, 50 psi) than the much harsher conditions required without cavitation (350 C, 3,000 psi). The extent of PFA reaction will be determined and the fluorinated reaction products will be identified. Following successful feasibility demonstration, a technology for the disposal of AFFF will be developedThe anticipated technology will have potential commercial applications that include disposal of AFFF for DOD and other contaminated sites, as well as destruction of other halogenated pollutants.