Removal and Recovery of Organic Vapor Emissions by Fixed-Bed Activated Carbon Fiber Adsorber-Cryogenic Condenser

摘要

Abatement of toxic volatile organic compounds (TVOCs) emitted to the atmosphere has become a concern because of the magnitude of the emissions and their potential health effects to humans and deleterious effects to the environment. New control technologies are being developed to separate and remove those toxic compounds from gas streams for reuse of the TVOCs in the process that generated them. This project evaluated the ability of an activated carbon fiber cloth (ACFC) adsorption, electrothermal desorption, cryogenic-condensation system to remove 10 cu cm/min containing 1000 ppmv of methyl ethyl ketone (MEK) or toluene from air streams that are dry or at 90 percent relative humidity. Results indicate that MEK and toluene are readily adsorbed from the carrier gas streams with the ACFC adsorber. Electrothermal desorption is also effective at desorbing the TVOCs and water from the ACFC. Cryogenic condensation is also effective for the dry MEK and toluene desorption conditions. Economic analysis shows that capitol costs for a conventional thermal swing GAC adsorption system will be 1.7 times greater than this system for the toluene dry air stream. The MEK recovery credit will be approximately four times greater than the annual operating costs for the MEK dry air stream.