Condensers and carbon adsorption are two types of vapor recovery systems.  With condensation, the vapor stream is saturated before being condensed into a liquid.  Removal efficiency depends on the partial pressure and the hydrocarbons concentration in the vapor stream.  The lowest temperature necessary to condense the vapor dictates which coolant is used (water, brine solutions or Freon).  The condensation process does not produce any additional waste, but the recovered product may contain partially oxidized VOC that requires special disposal.

Carbon adsorption is more commonly used for vapor recovery, as it does not require elevated pressures or refrigeration to remove hydrocarbon vapor.  The higher molecular weight of hydrocarbons, combined with temperatures below 38°C (100°F) and less than 50 percent humidity, results in higher removal efficiencies.  Despite fluctuating flow rates and concentrations, carbon adsorption systems safely remove contaminants at very low-pressure losses 249 Pa (1” w.c.).  These systems do not require blowers.  The carbon can be regenerated a finite number of times, on- or off-site, before it is completely spent.

Flare Devices
Ignition Sources
Vapor Space Purging