Tehran University of Medical Sciences Journal of Air Pollution and Health 2476-3071 1 2 2016 05 29 51 60 EN Kazem Naddafi Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran Alireza Mesdaghinia Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Mehrnoosh Abtahi Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Department of Environmental Health Engineering, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran Kamyar Yaghmaeian Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Center for Solid Waste Research (CSWR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran Ramin Nabizadeh Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran Nematollah Jaafarzadeh Department of Environmental Health Engineering, School of Public Health, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Noushin Rastkari Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran Reza Saeedi Department of Health Sciences, Faculty of Health, Safety and Environment, Shahid Beheshti University of Medical Sciences, Tehran, Iran Shahrokh Nazmara Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 2016 05 29 2016 05 29 Introduction: Dichloromethane (DCM) is an air pollutant emitted mainly through industrial application. In this study, removal of DCM from waste gas streams using a pilot-scale hybrid bubble column/biofilter (HBCB) bioreactor was studied in steady state. Materials and methods: The hybrid bioreactor had two compartments: bubble column bioreactor and biofilter.The experiments were carried out with relatively constant concentration of DCM (approximately 240 ppm) and variable empty bed residence time (EBRT) of 50, 100, 150 and 200 s in steady state. Results: The average DCM removal efficiency of the HBCB bioreactor at EBRT of 200 and 150 s were 79 and 71%, respectively, but further reduction of EBRT significantly decreased the DCM removal efficiency. DCM removal rate was determined to be in the range of 12.1 g/m3.h to 19.6 g/m3.h. The first order rate equation best described the kinetic data of biofiltration (R2>0.99) with kinetic constant of 0.0114 1/s. The mixed liquor characterization indicated that the daily adjustment of pH and EC was sufficient to prevent any limitation in the performance of the HBCB bioreactor. Conclusions: This study showed that the HBCB bioreactor could be an efficient, economical and flexible option for DCM removal from waste gas streams. https://japh.tums.ac.ir/index.php/japh/article/view/35 https://japh.tums.ac.ir/index.php/japh/article/download/35/8