廃水処理に伴うN₂O放出量の低減に向けた発生機構の解析

抄録

Tropospheric increment of N₂O is of great concern in global warming issue and stratospheric ozone chemistry, which is largely attributed to the human-induced alteration of nitrogen cycle. Biological waste water treatment is a terminal destination of industrially fixed nitrogen as well as a hot spot for N₂O emission. The present understanding of microbial pathways suggests that N₂O is a by-product of ammonium oxidation and an obligate intermediate product of denitrification. Therefore, a conventional mass balance approach is insufficient to elucidate producing mechanisms of N₂O in common environments where coupling of nitrification and denitrification occurs. In this context, we proposed the measurement of natural abundance of nitrogen and oxygen isotopes to be applied for analysis of N₂O dynamics in a waste water treatment facility, and discussed future perspective of the technique.