Assessment of N2O emission from a photobioreactor treating ammonia-rich swine wastewater digestate

作者：Mezzari Melissa P^*; da Silva Marcio L B; Nicoloso Rodrigo S; Ibelli Adriana M G; Bortoli Marcelo; Viancelli Aline; Soares Hugo M

来源：Bioresource Technology, 2013, 149: 327-332.

DOI：10.1016/j.biortech.2013.09.065

• Ammonia
• Greenhouse gases
• Microalgae
• Real-time PCR
• Swine wastewater

This study investigated the interactions between naturally occurring bacteria and the microalgae Chlorella vulgaris within a lab scale photobioreactor treating ammonia-rich swine wastewater digestate effluent. Nitrification and denitrification were assessed by targeting ammonia monoxygenases (amoA), nitrate (narG), nitrite (nirS), nitric oxide (norB) and nitrous oxide (nosZ) reductases genes. Oxygen produced from microalgae photosynthesis stimulated nitrification. Under limiting carbon availability (i.e., <1.44 for mg TOC/mg NO2-N and 1.72 for mg TOC/mg NO3-N), incomplete denitrification led to accumulation of NO2 and NO3. Significant N2O emission (up to 118 mu g N2O-N) was linked to NO2 metabolism in Chlorella. The addition of acetate as external carbon source recovered heterotrophic denitrification activity suppressing N2O emission. Effluent methane concentrations trapped within photobioreactor was removed concomitantly with ammonia. Overall, closed photobioreactors can be built to effectively remove nitrogen and mitigate simultaneously greenhouse gases emissions that would occur otherwise in open microalgae-based wastewater treatment systems.

• 出版日期2013-12