Chemical Storage Tank Scrubbers (aka "CST scrubbers" or venting scrubbers) are packed towers that reduce emissions of hazardous or corrosive vapors. The systems use Tri-Packs tower packing, which provides maximum surface contact between gas and scrubbing liquid. This optimizes scrubbing efficiency and minimizes the depth of packing depth needed for effective operation.
The distinctive shapes of Tri-Packs' ribs, struts, and drip rods provide superior wetting characteristics and low-pressure drop; a highly uniform liquid distribution is maintained throughout the tower.
Tri-Packs significantly reduces both clogging, (there are no flat surfaces or minute openings to harbor particulate) and puddling (because it's free of corners and valleys and minimizes liquid flow down the wall surfaces.) Tri-Packs also prevent dry spots and compression interlock, two phenomena common to traditional packing media. Both conditions cause liquid and air channeling and diminish the efficiency of the scrubber.
Systems are engineered for the application, in capacities of 200 to 50,000 acfm. Nine factors that impact system design include the concentration of the acid or alkali in the tank, the type (pumped or pneumatic) and rate of transfer (airflow), whether or not there is tank breathing, the diameter, length, and configuration of the transfer line, the pressure rating of the storage tank, the size of the vent, and whether scrubbing is continuous or batch. CST Scrubber construction is polypropylene for most applications, and systems can be installed indoors or outdoors.
Three CST configurations are offered: single scrubber/single tank, multiple tank/multiple contaminants ducting to a single scrubber, and "emergency release" which is primarily for contaminants such as ammonia and chlorine if a processing or storage room becomes compromised.
