Estimate of Nitrous Oxide Emission Factors from Municipal Wastewater Treatment Plants

하수처리 공정별 아산화질소(N$_2$O) 배출계수 산정

  • Yang, Hyung-Jae (Environmental Cap System Research Department, National Institute of Environmental Research) ;
  • Park, Jung-Min (Environmental Cap System Research Department, National Institute of Environmental Research) ;
  • Kim, Min-Jung (Environmental Cap System Research Department, National Institute of Environmental Research)
  • 양형재 (국립환경과학원 환경총량관리연구부) ;
  • 박정민 (국립환경과학원 환경총량관리연구부) ;
  • 김민정 (국립환경과학원 환경총량관리연구부)
  • Published : 2008.12.31

Abstract

Nitrous oxide(N$_2$O) is well known as a greenhouse gas that contributes to the global warming (310 times more per molecule than carbon dioxide) and to the destruction of the ozone layer. The objective of this study is to estimate N$_2$O emission factor using an emission isolation flux chamber from municipal wastewater treatment plants. N$_2$O gas was analysed by GC/ECD with 6 port gas sampling valve. The results of this study were as follows. N$_2$O emission factor of 5-Stage process from Y wastewater treatment plants was lowest as 0.94 g-N$_2$O/kg-TN. And that of other processes were 2.65 g-N$_2$O/kg-TN for Activated sludge process, 9.30 g-N$_2$O/kg-TN for Denipho process, and 26.73 g-N$_2$O/kg-TN for Sequencing Batch Reactor process. We have known that 5-Stage process is most appropriate process to reduce greenhouse for municipal wastewater treatment plants.

하수처리과정에서 온실가스인 N$_2$O가 발생하는데, N$_2$O의 지구온난화 기여율은 CO$_2$의 310배에 달한다. 본 연구에서는 하수처리공정에 따라 온실가스 배출계수가 어떤 차이를 보이는지를 분석하기위해 운전 중인 4개의 하수처리공정을 대상으로 조사하였다. 배출계수 산정을 위한 시료채취는 Flux Chamber를 이용하였으며, N$_2$O 정량은 6 port gas sampling valve가 장착된 Agilent사의 GC로 분석하였으며, 검출기는 ECD를 사용하였다. 하수처리공정별 오염물질 유입 부하에 대한 N$_2$O 배출계수 산정결과 5-stage공정은 0.94 g-N$_2$O/kg-TN으로 가장 낮았으며, 다음으로 활성슬러지공정이 2.65 g-N$_2$O/kg-TN, Denipho공정이 9.30 g-N$_2$O/kg-TN, 그리고 SBR공정이 26.73 g-N$_2$O/kg-TN으로 가장 높게 나타났다. 하수처리에서 N$_2$O 배출량 감소를 위해서는 조사대상 시설 중 5-stage 공정이 가장 적절한 것으로 평가하였다.

Keywords

References

  1. 平出, 中島, "下水道施設から排出される地球溫暖化物質($CH_4$, $N_2O$)排出Inventory算定と排出制御技術," 日本下水道協會誌, 42(508), (2005)
  2. 日本國立環境硏究所, "$N_2O$,CH4放出原および放出量究明に關する硏究," (1993)
  3. IPCC Forth Assessment Report, IPCC(2007)
  4. US EPA, "Measurement of Gaseous Emission Rates from Land Surfaces using and Emission Isolation Flux Chamber User's Guide," EPA-68-02-3889-1986
  5. 강경희, "플럭스 챔버를 이용한 하수처리장 HAPs 배출특성 연구," 서울시립대학교 대학원 공학박사학위논문(2006)
  6. Gostelow, P., Longhurst, P., Parsons, S. A., and Stuetz, R. M., "Sampling for the Measurement of Odours," IWA Publishing(2003)
  7. Debruyn, Walter, Lissens, Gilbert, Rensbergen, Jan Van, VITO, Boeretang 200, B-2400 MOL, Belgium(1993)
  8. 日本國立環境硏究所, "$N_2O$,CH4放出原および放出量究 明に關する硏究," (1992)
  9. 日本國立環境硏究所, "$N_2O$,CH4の標準活性汚泥法および標準活性汚泥法および嫌氣.無酸素.好氣法から放出量の比較解析," (1996)
  10. 花木啓祐, "排水の生物學的窒素除去實規模施設から亞酸化窒素の發生制御に關する硏究," 東京大學 先端科學技術硏究Center(1997)
  11. Inamori, R., Gui, P., Dass, M., Matsumura, K., Xu, Q., Kondo, T., Ebie, Y., and Inamori, Y., "Investigating $CH_4$ and $N_2O$ emissions from eco-engineering wastewater treatment processes using constructed wetland microcosms, Process Chemistry," PRBI-8096, p. 11(2006)
  12. 日本國立環境硏究所, "廢水處理から發生する$N_2Ogas$制御硏究," (1991)
  13. 花木啓祐, 鄭葒, 松尾, "脫窒から一酸化二窒素生成と操作因子の關係," 東京大學先端科學技術硏究Center(1992)
  14. 日本國立環境硏究所, "$N_2O$,CH4放出原および放出量究明に關する硏究," (1994)
  15. 水落元之, 佐藤和明 등, "GHG $CH_4$, $N_2O$の標準活性汚泥法および嫌氣 . 無酸素 . 好氣法から放出量の比較分析," 日本水處理生物學會誌, 35(2), 109-119(1999)
  16. Kimochi, Y., Inamori, R., Mizuochi, M., Xu, K., and Matsumura, M., "Nitrogen Removal and $N_2O$ Emission in a Full-Scale Domestic Wastewater Treatment Plant with Intermittent Aeration," J. Fermentation and Bioeng., 86(2), 202-206(1998) https://doi.org/10.1016/S0922-338X(98)80114-1
  17. Gaelle Tallec, Josette Garnier, Gilles Billen, Michel Gousailles, "Nitrous oxide emissions from secondary activated sludge in nitrifying conditions of urban wastewater treatment plants: Effect of oxygenation level," Water Res., 40, 2972-2980(2006) https://doi.org/10.1016/j.watres.2006.05.037