Estimation of the removal of organic priority pollutants by the powdered activated carbon treatment process

Abstract

ABSTRACT: Federal guidelines have been issued that regulate the aqueous discharge concentrations of priority pollutants for the organic chemicals, plastics, and synthetic fibers industries. Insufficient data existed in the literature to allow estimations of the removal of priority pollutants by a wastewater treatment plant (WWTP). The removals of 18 problem organic priority pollutants were measured in five parallel, aerated, continuous, mixed reactors. The influent to the laboratory pilot plants was primary effluent from an industrial 1.75 m3/s (40 Mg/d) WWTP at Du Pont's Chambers Works in Deepwater, N. J. This plant utilizes powdered activated carbon in combination with activated sludge (PACT® Process) in the aeration tanks. The kinetic coefficients that characterize removal by biodegradation, powdered activated carbon adsorption, and air‐stripping were obtained from the pilot‐plant data, and a steady‐state model was used to predict priority pollutant removals. Good agreement was obtained,”with the exception of three compounds that were batch discharged from the process sources, which invalidated the steady‐state assumption. The model was used to design a second stage PACT unit and to determine source control requirements. The model also can be used to estimate the relative importance of the three removal mechanisms in order to adjust WWTP operating conditions to enhance the removal of specific compounds.