Innovative synthetic biofilter media has revolutionized biofilter technology for removal of hydrogen sulphide (H:S) odours from several wastewater treatment facilities across North America. The major drawback of biofilter technology in the past was use of organic wood-based media, which had several problems including high-pressure drop, frequent media replacement, lack of nutrients, poor buffering properties and self degradation of the media. Modular and in ground biofilters are now filled with this innovative synthetic media on which microorganisms grow over a higher surface area as thin biofilms where odour contaminants such as hydrogen sulphide and reduced sulphur compounds diffuse and are subsequently biologically oxidized into odourless products. Typically HiS has been identified as the major odour contributor associated with waste water treatment applications. Other compounds such as dimethyl sulphide (DMS), dimethyl di-sulphide (DMDS), methyl mercaptans and various volatile organic compounds (VOCs) also contribute significantly to nuisance complaints due to odours. The removal of H2S does not necessarily mitigate the odour problem unless these compounds are addressed. This paper focuses on the elimination of H2S using synthetic BIOSORBENS biofilter media in the absence and presence of other reduced sulphur compounds. Laboratory and field data from several BIOREM's biofilter installations that treat sulphur odorous air from wastewater treatment applications are discussed.
Biofilter, synthetic media, BIOSORBENS™, hydrogen sulphide, reduced sulfur compounds, dimethyl sulphide (DMS), dimethyl di-sulphide (DMDS), and methyl mercaptans
Municipal operations emit highly odorous sulfur compounds including hydrogen sulfide (H2S), dimethyl sulfide (DMS), dimethyl di-dulfide (DMDS), and methyl mercaptans (MM). Emission of these gases is a nuisance due to rotten egg (H2S), rotten cabbage (DMS), sulfide, (DMDS) and pungent (MM) odor characteristics. Odor threshold levels of these compounds are in parts per billion (ppb) levels (Bertucci et al., 1994). Regulations are in effect for controlling emission of these gases at municipal facilities. Conventional control methods used in removing these contaminants from air are activated carbon adsorption, chemical oxidation, and incineration.