Small-scale demonstration of nonthermal plasma VOC treatment at Tinker AFB

Abstract

Nonthermal plasma (NTP) technology is a promising candidate for the treatment of air pollutants. An NTP is different from a thermal plasma in that high energy electrons are used to create chemically active species without raising the gas to high temperatures. NTPs have the potential of simultaneous removal of multiple air pollutants with better control over treatment byproducts. A silent discharge plasma (SDP) configuration is one method of easily generating such a nonthermal plasma. Silent electrical discharge plasma (dielectric barrier) reactors can decompose gas-phase pollutants by free-radical attack or electron-induced fragmentation. The radicals or electrons are produced by the large average volume nonthermal plasmas generated in the reactor. In the past decade, the barrier configuration has attracted attention for destroying toxic chemical agents for the military, removing harmful greenhouse gases (oxides of sulfur and nitrogen - SO{sub x} and NO{sub x}), and treating other environmentally-hazardous chemical compounds (hydrocarbons, chlorocarbons, and chlorofluorocarbons). At the Los Alamos National Laboratory (LANL), the authors have been studying the silent discharge plasma for processing gaseous-based hazardous chemicals for approximately five years. The key objective is to convert hazardous or toxic chemicals into non-hazardous compounds or into materials which are more easily managed. The main applications have been for treating off-gases from thermal treatment units (e.g., incinerators, high-temperature packed bed reactors, arc melters; low-temperature thermal desorbers), and for abating hazardous air-pollutant emissions (e.g., industrial air emissions, vapors extracted from contaminated soil or groundwater).