Reduction of nitrous oxide emissions in municipal WWTPs by applying a bio-scrubber to treat the exhaust air from side-stream deammonification
01.03.2022 - 30.08.2024
Federal Ministry Republic of Austria, Agriculture, Regions and Tourism
Dr. Vanessa Parravicini
Brief information on the project
The research project will explore an innovative concept to reduce nitrous oxide emissions for medium-sized to large municipal sewage treatment plants with anaerobic digestion. This is based on two essential cornerstones: i) The autotrophic nitrogen removal via deammonification in the sludge dewatering effluent in side-stream and ii) the treatment of the nitrous oxide-rich exhaust-air from the deammonification basin via a denitrifying bio-scrubber with wastewater as organic carbon source. By removing nitrogen in side-stream, favourable process conditions for the reduction of N2O emissions in the activated sludge process in the main-stream waterline are created. The deammonification process in the side-stream, in which N2O is also released, exhibits more suitable conditions for the use of a bio-scrubber to remove N2O than the main-stream.
The denitrifying bio-scrubber is the core of the new treatment concept and the object of the research work. Its suitability to treat the exhaust air from the deammonification process in the side-stream flow is to be thoroughly checked on a laboratory scale. The ecological and economic impact of the overall concept will be assessed and the reduction potential for the Austrian wastewater treatment sector will be estimated.