Journal of Hydrogen and New Energy (한국수소및신에너지학회논문집)

The Korean Hydrogen and New Energy Society (한국수소및신에너지학회)
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A Study on the Thermal and Pollution Performances of the Heating Boilers with NG-H2 Mixture Ratio

난방용 보일러에서 NG-H2 혼소율에 따른 열 및 공해 성능의 검토

  • SEO, JUNSUN (Department of Mechanical Engineering, Inha University Graduate School) ;
  • KIM, YOUNG-JIC (Department of Mechanical Engineering, Inha University Graduate School) ;
  • PARK, JUNKYU (Kyung Dong Navien) ;
  • LEE, CHANG-EON (Department of Mechanical Engineering, Inha University)
  • 서준선 (인하대학교 기계공학과 대학원) ;
  • 김영직 (인하대학교 기계공학과 대학원) ;
  • 박준규 (경동나비엔) ;
  • 이창언 (인하대학교 기계공학과)
  • Received : 2021.10.28
  • Accepted : 2021.12.16
  • Published : 2021.12.30
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Abstract

Hydrogen is evaluated as one of the new energy sources that can overcome the limitations and pollution problems of conventional fossil fuels. Although hydrogen is CO2-free, attention is required in NOx emission and flame stability in order to use hydrogen in existing gas fuel system. However, use of electric grids is an unrealistic strategy for decarbonization for residential and commercial heating. Instead, use of H2 that utilizes city gas grid is suggested as a reasonable alternative in terms of compatibility with existing systems, economic feasibility, and accessibility. In this study, the thermal efficiency and NOx performance of the boiler according to the H2 mixture ratio and vapor humidified ratio are reviewed for a humidified NG-H2 boiler that vapor humidity to combustion air. Mixed fuel with H2 (20%) is almost similar to NG in terms of efficiency, flame temperature, and pollution performance. Thus, it is expected to be directly compatible with the existing NG system. If the exhaust temperature of the H2 boiler is lowered to around 60℃ at a humidified ratio of 15-20%, the NOx emission concentration can be suppressed to about 5-10 ppm. The level of efficiency reaches 87% of the rated load efficiency, which is equivalent to the highest grade achievable.

Keywords

Acknowledgement

본 논문은 2020년도 산업통상자원부 및 산업기술평가관리원(KEIT-20010957) 및 2018년 산업통산자원부 한국에너지기술평가원(KETEP-2018201010635A)의 지원에 의한 연구입니다

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