The objective of this work was to evaluate toluene degradation in a trickle bed reactor when the loading was carried out by changing the air flow rate. The biofiltration system was inoculated with a mixed microbial population, adapted to degradation of hydrophobic compounds. Polypropylene high flow rings were used as a packing material. The system was operated for a period of 50 days at empty bed residence times ranging from 106s to 13s and with a constant inlet concentration of toluene of 100 mg.m-3. The reactor showed high removal efficiency at higher contact times and increasing elimination capacity with higher air-flow rates. The highest EC value reached was 9.8 gC.m-3.h-1 at EBRT = 13s. During the experiment, the consumption of NaOH solution was also measured. No significant variation of this value was found and an average value of 3.84 mmol of NaOH per gram of consumed carbon was recorded.

The objective of this work was to determine the influence of microbial inoculation on degradation efficiency. Three biofilters were used for the treatment of waste gas. A mixture of compost and perlite (8:2) served as the packing material. One biofilter was inoculated with a constructed microbial population. The second remained uninoculated, having the natural population present in the compost. The third biofilter was uninoculated and the packing material was sterilized. The degradation ability of the uninoculated biofilter started to drop after 18 days, while the removal efficiency of inoculated biofilter was stable. The sterile biofilter proved to have no removal efficiency. Moisture content of the packing and ability of the packing to keep moisture was tested. The results showed a significant dependence of the degradation efficiency on the packing moisture content, with highest removal efficiency observed at 70 % moisture content.