Odour Treatment Systems are especially used to reduce or completely eliminate bad odours that occur in Wastewater Pumping Stations and Wastewater Treatment Plants. The units where bad odours occur are pumping stations, inlet structures, screen structures, sludge thickening and digester units, sludge dewatering units, transport and storage of dewatered sludge. The main source of odour occur in Wastewater Treatment Plants is the gases formed as a result of the decomposition of chemicals and organic substances coming with wastewater.