Treatment of waste gas containing diethyldisulphide (DEDS) in a bench scale biofilter

Waste gas containing diethyldisulphide (DEDS) is generated from various industries including pulp and paper, refinery, rayon and molasses based distilleries, etc. DEDS has odour threshold detection with an average concentration of 10−9 mg/m3 at 25 °C. DEDS is toxic to bacteria, fungus and also to mammals when exposed for a long period. Waste gas containing DEDS require proper treatment prior to discharge into the environment. DEDS containing waste gas was treated in a biofilter, packed with compost along with wooden chips and enriched with DEDS degrading microorganisms. The biofilter could remove DEDS to the extent of 94 ± 5% at a loading of 1.60 g/m3/h with an empty bed retention time of 150 s. At optimal operating conditions, the average moisture content required by the biofilter was in the range of 60–65%. The biodegradative products of DEDS were thiosulphate and sulphate.