Treatment quality of an air scrubber refers to the general percentage of a pollutant that the scrubber is able to remove. In other words, this measure shows how effective the scrubber performs. The treatment quality of a scrubber is often measured interference to particle and gas pollutants, as some air scrubbers may be far less effective against a certain type of pollutant, which hinders its ability to be used as the only means of pollution control. Several factors have an impact on the treatment quality of a scrubber, including the scrubber design, the substance used for particle and gas collection, absorber material, polluted air residence time, etc.
Among wet air scrubbers, venturi wet air scrubbers, packed bed wet scrubbers, and cyclonic spray scrubbers are the most common.
Venturi wet air scrubbers are most effective when used to collect particulate matter; the average estimated removal efficiency of a venturi scrubber is 90-99%. The treatment quality can be improved by increasing a pressure drop and liquid-to-gas ratio, namely adding more water to the scrubber. However, venturi wet air scrubbers are not effective at gas removal. The average treatment quality of gas pollutants is 30-60%, which implies that venturi scrubbers should not be used if removal of gaseous pollutants is the only concern. The inefficiency of venturi air scrubbers is caused by a very short contact time between the liquid and gas phases; this is a result of high velocities of inlet air. To maximize the gas absorption rate venturis are modified to operate at a different set of conditions from those used to collect particles.
Packed bed scrubbers are more adept to gas scrubbing as high concentrations of particulate matter clogs the bed easily. The treatment quality of gas pollutants is estimated to be around 99%, however, scrubbing of particulate matter is far less effective and damages the packed bed.
Cyclonic spray scrubbers are typically used for particulate matter collection. Particles larger than 5 µm are generally collected with 90% efficiency. Cyclonic scrubbers are less effective than venturis as they are not able to provide the same degree of useful turbulence. Cyclonic scrubbers are far less effective in gas collection due to the limited contact time between gas and liquid inside the scrubber thus reducing absorption efficiency. Therefore cyclonic wet air scrubbers are only used for the removal of very soluble gases.
Being a new type of wet air scrubber, Scroiler™ provides improved air treatment quality and can be used for both particle matter and gas collection. The treatment quality of Scroiler™ is generally 99.95-99.99% for both types of pollutants. Besides high efficiency, Scroiler™ possesses a number of advantages over conventional wet scrubbers – Scroiler™ is compact, omnivorous, eco-friendly, economical, and low-maintenance.