The treatment of waste air containing phenol vapors in biotrickling filter

This research aimed at investigating the biodegradation of phenol contaminated-air streams in biotrickling filter. The effect of inlet concentration (200–1000 ppmv) and empty bed contact time (EBCT) (15–60 s) were investigated under steady state, transient and shock loading, and shutdown periods. Upon rapid start up operation, inlet phenol concentrations of up to 1000 ppmv did not significantly affect the performance of the biotrickling filter at EBCT of 60 s, so that removal efficiency was well greater than 99%. In addition, the EBCT as low as 30 s did not have detrimental effects on the efficiency of the bioreactor and phenol removal was greater than 99%. Decreasing the EBCT to 15 s reduced the removal efficiency to around 92%. The maximum elimination capacity obtained in the biotrickling filter was 642 gphenol m−3 h−1, where the removal efficiency was only 57%. Results from the transient loading experiments revealed that the biotrickling filter could effectively handle the variations of the inlet loads without the phenol removal capacity being significantly affected.