Carbon is employed in adsorption processes for the removal of organic, inorganic, and taste and odor control compounds. Granular Activated Carbon (GAC) and Powder Activated Carbon (PAC) are two leading adsorption treatments, the former utilizing a carbon bed and the latter employing a contact basin. Carbon slurry tanks require level monitoring.
Handling and safety problems are associated with the fly-away dust and difficult-to-wet characteristics of carbon. As carbon buildup often chokes mechanical level controls, non-contact monitoring technologies are popular. Contact level sensing should use single rod probes to avoid media buildup.