In situ decontamination of spills and landfills by radio frequency heating

A system for the in situ decontamination of a region at or near the surface of the earth contaminated with hazardous materials comprising

• a transmission line excitor,
• a source of radio frequency energy,
• means for coupling said radio frequency energy to said transmission line excitor, the dimensions of said excitor relative to the wave length of said radio frequency assuring that said energy is substantially bound to said excitor to act as a bound-wave excitor without substantial radiation, and a said excitor being disposed relative to said region to couple bound energy therefrom to materials in said region,
• a containment structure disposed over said region for containing and collecting vapors emanating from said region, said containment structure including a vapor barrier and an electromagnetic shield, and
• means for condensing at least a portion of the vapors collected.

A method for the in situ decontamination of a water-containing region at or near the surface of the earth contaiminated with harzardous materials comprising

• heating said region with bound radio frequency energy from a bound-wave fringing-field transmission line excitor disposed above said region to a temperature above the boiling point of water to boil water and thereby increase the permeability of the region, said energy being bound to said excitor without substantial radiation,
• continuing said heating with bound radio frequency energy by dielectric heating after said water has boiled from an upper portion of said region to heat said upper portion to elevated temperatures substantially above the boiling point of water and evaporate at least some of said hazardous materials, at the same time boiling water in a lower portion of said region below said upper portion to provide steam drive driving vapors upward from said upper portion,
• containing and collecting vapors emanating from said upper portion,
• condensing at least a portion of the vapors collected, and
• rendering relatively innocuous any collected vapors and condensed vapors.