Reduction potential in nitrous oxide emissions from wastewater treatment plants through optimization of operation

Duration:
2012-2014

Contct Person:
Dr. Vanessa Parravicini vparravi@iwag.tuwien.ac.at
Dr. Karl Svardal svardal@iwag.tuwien.ac.at

Projektpartner:
Umweltbundesamt, opens an external URL in a new window

Sponsored by the Federal Ministry of Agriculture, Forestry, Environment and Water Management

Short description:

Currently, only sporadic measurements of nitrous oxide (N2O) emissions from wastewater algae are available in Austria. This lack of data not only makes it difficult to estimate nitrous oxide emissions released as a by-product during biological wastewater treatment, but also to gain a better understanding of the formation mechanisms of this climate-relevant gas. Therefore, one focus of this project is the concrete measurement of nitrous oxide emissions at selected, municipal wastewater treatment plants, where the specific operating conditions for nitrogen oxidation and removal are simultaneously recorded.  The better understanding of the influencing factors of N2O production/emission at municipal WWTPs should allow to derive operational or design measures to reduce N2O emissions at municipal WWTPs.

Due to the climate protection relevance of nitrous oxide (N2O), a reduction of N2O emissions from Austrian municipal wastewater treatment plants should also be aimed for within the framework of the Austrian Climate Protection Act (BGBl. I 106/2011). Currently, only isolated measurements of N2O emissions from wastewater treatment plants are available. This lack of data not only hampers the estimation of nitrous oxide emissions released as a by-product during biological wastewater treatment, but also a better understanding of the formation mechanisms of this climate-relevant gas. Therefore, one focus of this project is the concrete measurement of nitrous oxide emissions at selected, municipal wastewater treatment plants, where the specific operating conditions for nitrogen oxidation and removal are simultaneously recorded.

The better understanding of the factors influencing N2O production/emission at municipal WWTPs should allow to derive operational or design measures to reduce N2O emissions at municipal WWTPs. By estimating the costs for the implementation of the respective measures, it should also become apparent which measures and with which effort can guarantee a relevant contribution to the reduction of N2O emissions at wastewater treatment plants.

One of the objectives of the project is to develop a comprehensible calculation model for estimating nitrous oxide emissions from municipal wastewater treatment plants as a function of process technology, operating conditions and wastewater composition. Based on an exact classification of the Austrian municipal wastewater treatment plants in corresponding classes, the calculation model should make it possible to extrapolate the total emission of N2O on a national level. Thus, a review of the current, standardized calculation approaches will also be possible. Similarly, the reduction potential of N2O emissions at municipal wastewater treatment plants in Austria will be estimated.