Treatment of polluted air stream using a pilot scale biofilter

Back ground and Aim: Benzene is an important pollutant that is released into the air from diverse sources such as chemical industry, crude oil, petrochemical industries, combustion, etc. It can significantly affect the health of human and environment; therefore, it is necessary to remove it from emissive sources. In this study, Benzene removal from polluted air using a biofilter was assessed.Materials and Methods: A three section biofilter (total height of 140 cm) packed with a mixture of scoria- bagasse –compost was used to remove Benzene from air. Effects of different inlet loading, various EBRTs (30, 60, and 90 s), and the biofilter bed height on the biofilter efficiency were evaluated. Operating time was 80 days. Sampling and measurement were performed according to NIOSH method. Results: Results showed that average removal efficiency (RE) at concentration range of I (1.4-3.2 mg/m3), II (6.5-10.2 mg/m3), and III (16.5-20.5 mg/m3) were 96 ± 8, 91 ± 7 and 87 ± 7 percent, respectively. More than 50% of the total removal of the pollutant was occurred in the first section. Also, the average RE at EBRTs of 30, 60, and 90 seconds was 78 ± 6, 89 ± 8 and 97 ± 6%, respectively. Conclusion: According to the results, it can be concluded that the efficiency of the biofilter is increased by decreasing input loading, and increasing EBRT. In general, the removal efficiency for all the tested input concentrations was satisfactory. Due to the high efficiency, low compactness, and low pressure drop of the bed, it can be concluded the biofilter configuration used in this study is suitable and applicable for the removal of pollutants from airstream.

کلیدواژه ها:

Air ، Treatment ، Biofilter ، Benzen