The KSFM Journal of Fluid Machinery (한국유체기계학회 논문집)

Korean Society for Fluid machinery (한국유체기계학회)
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The Analysis on Exergy Loss and its Reduction Methods in Steam Desuperheating and Depressurizing Process

증기의 감온·감압과정에서의 엑서지 손실 및 저감방안 분석

  • Yi, Joong Yong (Graduate School, Department of Mechanical Engineering, Suwon University) ;
  • Lee, Chan (Graduate School, Department of Mechanical Engineering, Suwon University)
  • 이중용 (수원대학교 대학원 기계공학과) ;
  • 이찬 (수원대학교 대학원 기계공학과)
  • Received : 2015.07.14
  • Accepted : 2015.10.22
  • Published : 2015.12.01
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Abstract

The present paper presented and applied an exergy analysis method to evaluate the magnitudes and the locations of exergy losses in the conventional desuperheating and depressurizing process of high pressure and temperature steam delivery system. In addition, for the reduction of exergy losses occurred in conventional process, the present study proposed new alternative processes in which the pressure reducing valve and the desuperheater of conventional process are substituted with steam turbine and heat exchanger, and their effects on exergy loss reduction and exergy efficiency improvement are theoretically investigated and compared. From the present analysis results, the total exergy loss caused in conventional desuperheating and depressurizing process accounted for 66.5% of exergy input and 85% of the total exergy loss was due to the mixing between steam and cold water(e.g desuperheating). However, it was shown from the present analysis results that the present alternative processes can additionally reduce exergy loss by maximum 92.7% of the total exergy loss in conventional process, and can also produce additional and useful energy, the electricity of 220.6 kWh and the heat of 54.3 MJ/hr.

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References

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