With thermal desorption methods, waste are heated so that organic contaminants and water volatilize. Typically, a carrier gas or vacuum system transports the volatilized water and organics to a gas treatment system. Based on the operating temperature of the desorber, thermal desorption processes can be categorized into two groups: high temperature thermal desorption (HTTD) (320 to 560ºC or 600 to 1000ºF) and low temperature thermal desorption (LTTD) (90 to 320ºC or 200 to 600ºF). Thermal desorption is an ex-situ treatment process.