Eliminating N2O Emissions to Zero: ZeeLung™ MABR Shows the Way

MABR has been identified as a technology with the potential to significantly reduce N2O emissions from mainstream and sidestream biological treatment. Continuous monitoring data of N2O emissions from two different MABR operations are assessed – one in a warm climate and the other a cold climate. Results indicate, respectively, average emission factors of 0.4 and 0.8% with peak emissions, as characterized by the 90th percentile, of 0.5% and 1.2%. These results compare favorably with reported emission factors for conventional activated sludge. Factors that would impact design and feasibility of exhaust gas post-treatment are considered. In addition to a low N2O emission, MABR can dramatically decrease the airflow that carries this emission as well as minimizing emission “peaks”. By providing reliably low and stable N2O emissions, concentrated in a relatively small airflow, it is argued that MABR can be an important piece of the puzzle in eliminating one of the most significant contributors to a utility’s GHG emissions and carbon footprint.