Model Simulation of PCB Volatilization from Sediments

A one-dimensional mathematical model of the volatilization of PCBs from sediments was developed. A simple macrocosm of sediment, water and air that allowed for (pseudo) onedimensional transport of PCB was established to conduct PCB transport studies. Complete characterization of the sediment was performed. The sediment was spiked with two PCB congeners and mixed with overlaying natural water and aged for three months prior to testing. The PCB volatilization rate was determined for three different contamination levels, which were 47ppm (high), 24ppm (middle) and 14ppm (low). The DCB adsorption isotherm from sediment was obtained after equilibration for three months.Experimental results were used to calibrate and validate the mathematical model for the volatilization of DCB from sediments. The parameters were estimated using the data corresponding to 47ppm (high), 24ppm (middle), while the other set of data, 14ppm (low), was used to test the calibration of the model. The results showed that model simulation was able to predict experimental results under these conditions.