MODELING VOLATILE ORGANIC CONTAMINANTS FATE IN WASTE-WATER TREATMENT PLANTS

The need for the control of volatile organic contaminants (VOCs) has l ed to the development of a computer-based suite of mechanistic models collectively known as TOXCHEM, which predicts the fate of VOCs in wast ewater treatment plants. TOXCHEM includes both steady-state and dynami c models, and will predict the location and mass of VOC emissions from several locations within a wastewater treatment installation. Derivat ions are shown for expressions describing important removal rate coeff icients and VOC mass balances for each unit process of a secondary tre atment plant. Calibration of the model at pilot scale was conducted, a nd data from other full-scale investigations were used to verify the m odel. It was found that the TOXCHEM models predicted reasonably well a nd would improve as the true rate coefficients are established. This m odel has the potential to be an extremely useful tool for wastewater t reatment plant engineers and administrators of sewer use regulations.