Superfund Innovative Technology Evaluation (SITE)
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of Organic Contaminants In Air Using Advanced Ultraviolet Flashlamps
The photolytic oxidation process indirectly destroys volatile organic compounds (VOCs) in soils and groundwater. The process uses a xenon pulsed-plasma flash-lamp that emits short wavelength ultraviolet (UV) light at very high intensities. The contaminants are collected in the vapor phase, and the UV treatment converts the VOCs into less hazardous compounds. Because the contaminants are destroyed in the vapor phase, the process uses less energy than a system treating dissolved contaminants. The volatilized VOCs enter the photolysis reactor where a xenon flashlamp generates UV light. The plasma is produced by pulse discharge of electrical energy across two electrodes in the lamp. Destruction over 99 percent occurs within seconds. Full-scale testing was conducted at the Lawrence Livermore National Laboratory Superfund site in California. Soils at the site had high levels of trichloethene (TCE). The TCE was quickly destroyed; however, undesirable intermediates including dichloacetyl chloride (DCAC) were formed. DCAC further oxidizes into dichlorocarbonyl (DCC) which requires additional treatment.