Journal of the Korean Society of Marine Environment & Safety (해양환경안전학회지)

The Korean Society of Marine Environment and safety (해양환경안전학회)
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Analysis of Ammonium Carbamate Used as a NOx Reducing Agent for the SCR System of Marine Diesel Engines

선박용 디젤엔진 SCR 시스템에 NOx 환원제로 사용되는 암모늄 카바메이트의 물질 성분 분석 연구

  • Kim, Hongsuk (Engine Research Center, Korea Institute of Machinery & Materials) ;
  • Ryu, Younghyun (Division of Marine Mechatronics, Mokpo National Maritime University)
  • 김홍석 (한국기계연구원 그린동력연구실) ;
  • 류영현 (목포해양대학교 해양메카트로닉스학부)
  • Received : 2020.09.16
  • Accepted : 2020.10.28
  • Published : 2020.10.31
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Abstract

SCR technology, which uses urea-water as a NOx reducing agent, has been widely used to reduce NOx in marine diesel engines. However, as an alternative NOx reducing agent, solid-phase ammonium carbamate has several advantages, such as low-temperature NOx reduction performance and NH3 storage capacity. This study presents a method for evaluating the purity of ammonium carbamate using EA, FTIR, and XRD to investigate the change in the material characteristics of ammonium carbamate when it is exposed to various temperature and pressure conditions. In this study, it was found that the purity of ammonium carbamate can be effectively evaluated via EA analysis. The FTIR analysis results confirmed that the properties of ammonium carbamate did not change even after repeated heating and cooling under thermal decomposition temperature conditions, which may be applied to the SCR system of marine diesel engines. Additionally, it was found that when ammonium carbamate was exposed to the atmosphere for a long time, it transformed into ammonium carbonate.

선박용 디젤엔진의 NOx 환원제로 액체 우레아를 사용하는 SCR 기술이 널리 사용되고 있다. 하지만 액체 우레아 대신에 고체상의 암모늄 카바메이트를 NOx 환원제로 사용하면 저온 NOx 저감율 및 암모니아 저장용량 측면 등에서 다양한 장점이 있다. 이에 따라 본 연구에서는 암모늄 카바메이트를 EA, FTIR, XRD 방법으로 분석하여 순도를 관리하는 방법을 제시하고자 하였으며, 다양한 온도와 압력 조건에 암모늄 카바메이트가 노출되었을 때의 물질 변화 특성을 고찰하고자 하였다. 본 연구를 통하여 암모늄 카바메이트의 순도를 EA 분석을 통해 효과적으로 관리 할 수 있음을 알 수 있었으며, 선박용 디젤엔진의 SCR 시스템에 적용될 것으로 예상되는 열분해 온도 조건에서 가열과 냉각을 반복한 암모늄 카바메이트에 대한 FTIR 분석결과, 물질 특성은 변화하지 않는 것을 확인하였다. 또한, 대기 중에 장기간 노출된 암모늄 카바메이트는 암모늄 카보네이트로 물질 변화함을 알 수 있었다.

Keywords

References

  1. Chun, M., C. S. Yoon, and H. Kim(2017), A Basic Study on Physical Method for Preventing Recombination of Gas Product from the Decomposition of Ammonium Carbamate, Trans. Korean Soc. Mech. Eng. B, Vol. 41, No. 10, pp. 639-647. https://doi.org/10.3795/KSME-B.2017.41.10.639
  2. IMO(2008), International Maritime organization, NOx technical code 2008, Nitrogen Oxides (NOx): regulation 13. https://www.imo.org/en/OurWork/Environment/Pages/Nitrogen-oxides-(NOx)-%E2%80%93-Regulation-13.aspx.
  3. Kim, Y., H. Raza, S. Lee, and H. Kim(2020), Study on the thermal decomposition rate of ammonium carbamate for a diesel NOx reducing agent-generating system, Fuel 267.
  4. Lee, H., C. S. Yoon, and H. Kim(2013), A Study on Reaction Rate of Solid SCR for NOx Reduction of Exhaust Emissions in Diesel Engine, Transactions of KSAE, Vol. 21, No. 6, pp. 183-194. https://doi.org/10.7467/KSAE.2013.21.6.183
  5. Lee, H., C. S. Yoon, and H. Kim(2014), CFD Analysis on Gas Injection System of Solid SCR for NOx Reduction of Exhaust Emissions in Diesel Engine, Transactions of KSAE, Vol. 22, No. 5, pp. 73-83. https://doi.org/10.7467/KSAE.2014.22.5.073
  6. Ryu, Y., H. Kim, G. Cho, H. Kim, and J. Nam(2015), A Study on the Installation of SCR System for Generator Diesel Engine of Existing Ship, Journal of the Korean Society of Marine Engineering, Vol 39, No. 4, pp. 412-417. https://doi.org/10.5916/jkosme.2015.39.4.412
  7. Ryu, Y., H. Kim, W. Cho, and J. Nam(2017), Installation and characteristics of urea-selective catalytic reduction systems for nitrogen oxide reduction in marine diesel engine, Proc IMechE Part M: J Engineering for the Maritime Environment, Vol. 231(3), pp. 760-767.
  8. Shin, J. K., H. Lee, C. S. Yoon, and H. Kim(2014), Analytical Study on Re-solidification Materials (Ammonium Carbonate Intermediates) for NOx Reduction of Exhaust Emissions in Diesel Engine with Solid SCR, Transactions of KSAE, Vol. 22, No. 4, pp. 152-159.