Abstract: Ammonia gas is emitted by many industries, poultry farms and composting plants, it is a colorless, toxic, reactive and corrosive gas with a sharp odor. Its abatement at source is essential as it is irritating to the skin, eyes, nose, throat, and lungs. Biofiltration is a new emerging technology that is being used as a control technique. The present work evaluates the use of a mixture of cattle manure and rice husk as biofilter media to reduce Ammonia gas. This study investigates the effective depth of filter media to reduce Ammonia gas. The Ammonia gas concentrations at Municipal Compost Plant were found to be 500-700 µg/m3. A bench scale biofilter column was designed and operated to investigate the removal of Ammonia gas in the Municipal Compost Plant. Removal efficiency for bed depth of 20 cm was found to be 61.5% and for bed depth of 40 cm was found to be 71.45%. Nitrate concentration in biofilter media was initially 0.013 mg/L and at the end of 10th day the concentration was rised to 0.022 mg/L. It was observed that the Ammonia gas removal efficiency goes on increases as the accumulation of bacteria increases. Rice husk and cattle manure has been proved as an efficient media for removal of Ammonia gas from air stream.
Keywords: Ammonia gas, Biofiltration, Nitrate, Rice husk, Cattle manure.