ABSTRACT
Activated carbon treatment of water and wastewater has been demonstrated in both municipal and industrial applications. The use of granular activated carbon in wastewater treatment has been to use activated carbon as “tertiary” treatment following conventional primary and biological secondary treatment. Tertiary treatment processes involving carbon range from treatment of the secondary effluent with only activated carbon to systems with chemical clarification, nutrient removal, filtration, carbon adsorption, and disinfection. The use of pressure vessels for carbon contactors will increase the flexibility of operation, since it will allow the system to be operated at higher pressure losses. This may allow the carbon contact system to operate during upsets or variations in the wastewater flow. Backwashing reduces the resistance to flow caused by solids that have accumulated in the bed. Backwash frequency may be determined by build-up of head loss, deterioration of effluent turbidity, or at regular predetermined intervals of time.
