Optimization of combined air stripping and activated carbon adsorption for VOC removal from groundwater

Abstract

This study examines the combined treatment processes of air stripping and activated carbon adsorption for removing carbon tetrachloride, trichloroethylene and 1,4 dichlorobenzene from groundwater. Air stripping was used as a pretreatment with activated carbon as a polishing step. Optimization is achieved by determining the minimum operating and amortization costs for the variables of packing media depth versus carbon usage rate. A simplified design example illustrates the method of determining the optimum combination of treatment processes for the compounds and concentrations examined. The study included laboratory experiments which examined the air stripping performance of two different packing media as well as developing activated carbon isotherms. The transfer unit model was utilized to estimate the overall liquid mass transfer coefficient (KLa) for all three compounds at all experimental points.