Design, construction and optimization of two phase stirred tank bioreactor for elimination of xylene from airstream

Human and environment exposed to harmful factors، as the result of industrial pollutants. Volatile organic compounds (VOCs) play important role in photochemical reactions in troposphere layer of atmosphere and results in production of ozone and photochemical oxidants. In this study، a miniature stirred tank bioreactor was designed for treatment of waste gas containing xylene. In the next step، the bioreactor incubated with microbial consortiums with ratio of 1 to 3. The performance of bioreactor in treatment of xylene vapors in presence of 10% silicone oil، as an organic phase was assessed in concentrations ranging from 551 mg/m3 to 3330 mg/m3 for 432 hours. The results of xylene biodegradation showed that removal efficiency up to the concentrations of 2756 mg/m3 was 82 percent. Moreover، adding 10% silicone oil increased removal efficiency of BTX by 85. 7% in comparison with context without organic phase. The microbiological experiments on the bioreactor media showed that three spices of Pseudomonas putida، Chryseobacterium and Ralstonia pickettii were found، in the presence of xylene. Overall، the results of the present research revealed that application of two phase stirred tank bioreactors (TPPBs) for xylene from contaminated treatment of streams was successful.