Modeling hydrophobic VOC biofilter treatment in the presence of nutrient stimulation and hydrophilic VOC inhibition

Biofiltration is an evolving process for treating gas-phase volatile organic compounds (VOCs). Models are presented to simulate the biofilter treatment of hydrophobic components in the presence of inhibiting hydrophilic compounds. Both liquid and solid phase VOC degradation is considered and the metabolic rates of both may be stimulated by nutrient addition. In the reactor configuration simulated, stimulating nutrient is supplied without replenishment from the solid phase. Models are presented to represent the full kinetic behavior of the system and simplified steady-state reactor performance. Solutions are developed by finite difference approximation implemented in a Microsoft Excel spreadsheet application. Example simulations are presented to illustrate the impact of interaction mechanisms such as inhibition and nutrient stimulation, and to evaluate performance considerations such as the longevity of excess nutrients in reactor support medium.