Abstract: A non-thermal plasma (NTP) system treats fluid flows (e.g., air) containing pollutants (e.g., VOCs; particulate) using two or more stages, each operated to produce NTP with a respective frequency targeted toward one or more pollutants. NTP generation cell assemblies or dielectric barrier discharge devices are arranged in stages along a flow path. Parallel flow paths with multiple stages may be employed. NTP fields in successive stages operate at a different frequency, power density and/or waveforms, which are controlled to be a vibrational harmonic of a targeted compound. Power density can be adjusted to only create gaseous ionized species or to incinerate organic airborne, suspended particulate in situ. Automatic fault detection employs a split ground current so that an imbalance indicates a fault. A faulted component is automatically isolated. Automatic re-routing allows operation with only slightly degraded performance.

Abstract: A non-thermal plasma (NTP) system is used to treat air containing volatile organic compounds (VOC) and/or halogenated volatile organic compounds (HVOC), some of which may be odorous, and/or fine organic particulate (smoke) emissions to be released into the environment by commercial and/or industrial air exhausting, using one or more compound dielectric barrier discharge (DBD) devices that each incorporate a plurality of catalytically active DBD electrodes, catalytically active parts and dielectrics to develop one or more NTP fields so as to create sufficient reactive oxygen species, hydroxyl species and other highly ionized molecules and atomic species so as to cause the oxidation and/or reduction of VOC's and/or HVOC's and/or fine organic particulate contaminants in the air streams to be decomposed to simpler, non pollutant, non odorous compounds that can be subsequently released into the environment.