Biofilters in Mitigation of Odour Pollution - A Review

摘要

Odour is one of the most complex problems of all the air pollution problems. Undesirable odours contribute to air quality concerns that affect human lifestyles and are considered a nuisance to the general public. This study presents the role of biofilters for the control of volatile organic compounds (VOCs) and other odorous substances. Biofilters absorb the odorous and noxious gases into a biofilm where it is biodegraded by microorganisms into simpler and less toxic compounds like carbon dioxide, water and salts and use the energy and nutrients to grow and reproduce. About 95 percent of hydrogen sulfide (H_2S) and 80 percent of ammonia (NH_3) can be reduced by a well designed and managed biofilter. The mechanism of biofiltration depends on different factors viz., inlet gas concentration, empty bed residence time, bed height, type of media and these factors has a direct effect on the removal efficiency of a biofilter. Biofiltration, which has the ability to treat a broad spectrum of gaseous compounds has been regarded as a promising odour and gas treatment technology that is gaining acceptance in a number of industries and factories, being not only cost effective as compared to conventional techniques but are also environmental friendly.