Activated carbon cloth adsorption-cryogenic system to recover toxic volatile organic compounds

Abstract

There is an emergent need to reduce the emissions of toxic volatile organic compounds (VOCs) to the atmosphere. One strategy to reduce the emissions of VOCs from point sources is to use air pollution control devices on the sources' discharge streams. This paper describes the development of a new activated carbon cloth (ACC) adsorption system that is integrated with cryogenic vapor recovery to reduce the amount of VOCs emitted to the atmosphere from point sources and provide for reuse of the VOCs that are recovered. Electrical current is used to regenerate the ACC. ACC adsorption followed by electrothermal regeneration results in formation of a concentrated organic vapor which is cryogenically condensed from the gas phase. Electrothermal desorption allows for careful control of the desorption time and the concentration profile of the desorbed VOC to allow minimal use of cryogen. Adsorption, followed by cryogenic treatment enables VOC sources to meet air quality control regulations while providing a high quality liquid VOC product for reuse.