TRS developed a thermal remediation technique for the treatment of semi-volatile organic compounds (SVOCs), including coal tar, mercury, PCBs and perfluoroalkyl and polyfluoroalkyl substances (PFAS) in soil. To determine optimal temperature ranges for PFAS soil desorption and volatilization, TRS heated PFAS impacted soils to temperature ranges achievable by thermal conduction heating (TCH). While minimal thermal desorption occurred at 220°C, as temperatures approached 350 to 400°C, significant increases were observed. When soils were maintained in this temperature range for 10 to 14 days, TRS achieved greater than 99.9% reductions in PFAS concentrations. TRS received a patent for the FlexHeater® remediation services in February 2019. With substantial PFAS soil concentration reductions observed at temperatures achievable by TCH, thermal treatment has been shown to be an effective method to achieve low PFAS concentration limits recently established by certain states.
