Nitrous oxide (N2O), a very strong greenhouse gas contributing to climate change which can be emitted during biological wastewater treatment. Although the general nitrous oxide generation process in wastewater treatment plants is known, it is difficult to estimate the actual nitrous oxide emissions for a plant and specific operational mode. Therefore, long-term and on-site measurements of nitrous oxide generation are important to understand emission events at a plant and develop measures for reducing them.

The goal of LASSO-2 is to further develop a robust and reliable measurement method for nitrous oxide emissions in an activated sludge tank. Building on the proceeding LASSO project, the existing measurement of nitrous oxide emissions with gas hoods will be complemented by sensors for measuring dissolved nitrous oxide in the liquid phase. This analytical method requires less maintenance and support and is therefore suitable for long-term sampling campaigns. The validity of calculating emissions based on liquid sensors will be cross-checked in the project by comparing the two methods.

The results of the long-term measurement campaign LASSO-2 are an important contribution to the climate protection strategy of the Berliner Wasserbetriebe.