A concentrator system uses a combination of adsorption and thermal or catalytic technology.
A concentrator does not, in itself, destroy VOC, it merely concentrates it for more cost-effective destruction in a catalytic or thermal oxidizer.
Concentrator systems are particularly useful for process exhaust streams with VOC concentrations that are too high for cost-effective use of sacrificial systems and too low for cost effective use of thermal or catalytic oxidizers.
CECO EIS provides rotary concentrators that use either activated carbon or zeolite as the adsorbing media to remove the VOC from the main process exhaust stream prior to its discharge to atmosphere. In a concentrator system, the main air flow is passed through the rotating concentrator wheel where the VOC is adsorbed onto the surface of the carbon or zeolite, allowing cleaned air to discharge to atmosphere. At the same time a second and much smaller flow of hot air is passed through a separate section of the rotating wheel in the opposite direction. This smaller flow desorbs the VOC from the surface of the wheel ready for destruction in a catalytic or thermal oxidizer.
The net effect is the concentration of the solvent in the main air stream into a very much smaller airstream that can be cost effectively destroyed in an oxidizer. Concentration ratios of 8 to 15 times are normal and this will typically allow the oxidizer to run autothermally, with the excess heat generated in the oxidizer being used to heat the desorption air.