Study on the removal of indoor VOCs using biotechnology

With the improvement of living standard and civil building innovation, large numbers of building materials and decoration are being used. The emission of gaseous organic pollutants such as formaldehyde, benzene, toluene and xylene from these materials may trigger immediate or persistent potential harm to human health. In this study, with the combination of bake-out exhaust, biological treatment was applied to deal with volatile organic compounds (VOCs). Four bacterial strains were isolated from the biotrickling filter and were identified according to physiological and biochemical tests as well as bacterial fatty acids. As a result, they were characterized as Pseudomonas sp., Kocuria sp., Arthrobacter sp. and Bacillus sp. Under the conditions of gaseous flow rate of 600 L/h, surface liquid velocity of 3.14 m/h, pH 6-7 and temperature of 30 degrees C, VOCs could be degraded by using biological method before they were exhausted to the environment. For formaldehyde, benzene, toluene and xylene in the air stream with the concentration of 0-6.5 mg/m(3), 2.2-46.7 mg/m(3), 0.5-28.2 mg/m(3) and 4.1-59.0 mg/m(3), VOCs removal efficiencies of biotrickling filter ranged in about 100%, 65-70%, 93% and 85-90%, respectively.