Process for removing halogenated hydrocarbons and other solvents from a solvent laden air (SLA) stream

摘要

A process for removing halogenated hydrocarbons and other solvents from a solvent laden air (SLA) stream, includes the step of passing the SLA from an SLA intake through at least three adsorbers each containing an activated carbon bed. At least one adsorber undergoes regeneration while at least two other adsorbers operate in series in the adsorption mode. Regeneration is accomplished by passing a regenerating fluid such as steam through the bed. The steam and solvent vapor is condensed to form a liquid having at least one solvent rich fraction and at least one solvent poor fraction. This condensation product undergoes one or more separation steps to remove the solvent rich fractions from the solvent poor fractions. Non-condensibles are returned to the SLA intake. The SLA is pre-conditioned prior to the SLA inlet to remove extraneous contaminants and to control inlet conditions of temperature, relative humidity and flow rate. Removal efficiencies of 99 percent and above are attainable by the process.