Biological purification of exhaust air containing toluene vapor in a filter‐bed reactor

Experiments during a period of 93 days are reported on the treatment of waste air containing toluene vapor using a laboratory scale biofilter system packed with peat inoculated with specific florae (Pseudomonas type) and intermittently humidified with a nutrient solution necessary for the survival of the micro‐organisms. Design and operation parameters were regularly measured in order to check the performance of the biodegradation process. Under pseudo‐steady state conditions, a maximum elimination capacity of 70 g/m3.h was obtained for an inlet load of 190 g/m3.h. Elimination capacity data obtained agreed well with the predictions of two recognized zero order kinetic models. Also, the biofilm thickness as predicted from the Ottengraf and van den Oever model (1983) was around lmm.