Thermodynamic Analysis of Minimum Extraction Ratio for Coal-Fired CHP Plants

Abstract:

For evaluating the performance of combined heat and power district heating (CHP-DH) system, some thermodynamic indicators of CHP system, include energy efficiency, exergy efficiency, RPES and RAI, are introduced in this paper. Based on two condensed and heating dual purpose plants, the values of these indicators are calculated with different extraction ratio. The results show that RAI and RPES are more reasonable to be used to assess CHP-DH system and there is a minimum extraction ratio for each unit, which is 0.4 for given plants in this paper, to keep CHP-DH beneficial compared with separate heat and power (SHP) system. Besides, the minimum heat demand of CHP-DH system should be larger than the supplied heat correspond to minimum extraction ratio.

• Periodical: Applied Mechanics and Materials (Volume 472)
• Pages: 1052-1056
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.472.1052
• Online since: January 2014
• Authors: Chun Hui Liao, Zhi Gang Zhou, Jia Ning Zhao
• Keywords: CHP-DH, Extraction Ratio, RAI, RPES

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