Assessing the Ability of Biofiltration to Remove and Treat Diethanolamine from Contaminated Air Streams Using Compost-Based Biofilter

Document Type: Original Research Paper

Authors

1 Environmental Engineering, Civil Engineering Department, Khajeh Nasir University of Technology, Tehran, Iran

2 Faculty of Civil Engineering Department, Khajeh Nasir University of Technology, Tehran, Iran

Abstract

Biofiltration method is one of the most commonly used and most effective methods to remove
pollutants from the exhaust gas flow from different industries. One of the most important categories of air
pollutants is HAP (Hazardous Air Pollutants). This Study assesses the ability of biofiltration method to
remove and treat HAP DEA (Diethanolamine) from a gas stream through a laboratory-scale biofilter column
filled with granular compost, plastic hose pieces and municipal wastewater sludge. After start-up period with
an average concentration of 6 ppm, the main period began with an average DEA inlet concentration of about
51.7 ppm corresponding to a loading rate of 0.97 g/m3.hr and empty bed residence time of 89s, the biofilter
reached a removal efficiency of about 89% by two weeks. The maximum EC of 26.85 g/m3.hr was achieved at
a loading rate of 42.62 g/m3.hr, corresponding to an inlet concentration of DEA of about 258 ppm. Also the
loading rates less than 28 g/m3.hr are recommended to achieve the efficiency higher than 80%. The biofiltration
method had an efficiency of more than 80% for concentrations <170 ppm at 40°C. Also the maximum pressure
drop was recorded 13.8 mmH2O. It is because of using a mixture of shredded plastic hose pieces as a bulking
agent due to a high level of porosity in the bed.

Keywords