Investigating the species of microorganisms from activated sludge for handling phenol contaminated-air streams in biotrickling filter

Abstract

This research aimed at investigating the species of microorganisms from activated sludge is capable of handling gas-containing phenol vapor by means of trickling biofilter. By isolating and culturing microorganisms, two species, Bacillus pumilus and Bacillus thuringiensis, was discovered to dominate in phenol vapor removal equipment with high efficiency (about 90% with B. pumilus strain and 92% with B. thuringiensis strains) at inlet concentration about 650 - 850 mg/Nm3 and air flow of 1.5 L/min. Simultaneously, similar experiments were carried out with mixed microorganisms obtained removal efficiency of more than 80%. This result showed that microorganisms after being isolated gave higher performance than mixture of microorganisms. In particular, strain of B. thuringiensis could handle up to 3600 mg/Nm3 in inlet concentration at about 184.3 gphenolm-3.h-1 elimination capacity when removal efficiency was over 92%.