ABSTRACT
The desorbed chemical constituents are thermally destroyed in the process, and the reactivation of spent carbon containing perfluorooctane sulfonate, perfluorooctanoic acid, and other poly- and perfluorinated alkyl substances has been practiced for more than 10 years. Granular activated carbon (GAC) is a technology commonly used to remove organic species from a variety of water sources. Reactivation uses a high-temperature thermal process whereby adsorbed organic compounds are destroyed and the GAC's adsorptive capacity is restored. Types of thermal reactivation hardware include multiple hearth furnace, rotary kiln, infrared belt furnace, and fluidized bed furnaces. There are two primary types of reactivation furnaces that are commercially employed as the mainstay of a reactivation system: a multiple hearth furnace or a rotary kiln. During the reactivation process, the spent carbon will not only have the adsorbates removed and destroyed, but also, some of the carbon structure will be altered, changing some of the material properties compared with the original carbon.
