Biofiltration of formaldehyde, acetaldehyde, and acrolein from polluted airstreams using a biofilter

Abstract

BACKGROUNDAldehydes inhalation can adversely affect human and environmental health. This study was carried out to investigate the removal efficiency (RE) of three aldehydes including formaldehyde (FA), acetaldehyde (ACT), and acrolein (ACR) from airstreams using a biofilter packed with a new mixture of compost-scoria-sugarcane bagasse. Influence of inlet concentrations (0.63-25.15 mg/m(3)), empty bed residence time (EBRT) (40, 80, and 120 s), and bed height on the biofilter efficiency were measured for three separate 90-day periods. RESULTSThe mean RE of FA, ACT, and ACR were 92.6 4.6, 85.3 +/- 6.2, and 86.3 +/- 5.7, respectively. The mean RE at EBRTs of 40, 80, and 120 s was 84.9 +/- 6.1, 87.9 +/- 6.2, and 91.4 +/- 5.1, respectively. Results showed that the RE decreased with increasing inlet concentration, so that the minimum RE (80.2 +/- 4.7) was observed at the inlet concentration of 78.5-25.15 mg m(-3). Also, more than 68 of the overall RE occurred in section 1 of the biofilter, where the mean bacterial population (7.51 log(10)CFU g(-1)) was higher than that in section 2 (7.02 log(10)CFU g(-1)). CONCLUSIONSOwing to the high RE and negligible pressure drop of the bed, it can be concluded that a biofilter with the same conditions is a satisfactory technique to remove aldehydes from polluted air. (c) 2017 Society of Chemical Industry