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Exergy analysis of two water pumps from steam power plant at four different loads

  • 1 Faculty of Engineering, University of Rijeka, Vukovarska 58, 51000 Rijeka, Croatia
  • 2 University of Zadar, Maritime Department, M. Pavlinovića 1, 23000 Zadar, Croatia

Abstract

Paper presents exergy efficiency and loss analysis of condensate extraction pump (CEP) and main boiler feed pump (BFP) from a conventional steam power plant. Based on the required measured operating parameters at four different loads, it was observed that an increase in driving power for both pumps follows an increase in power plant cumulative developed power. Both analyzed pumps do not have the highest exergy losses at the highest observed load, as can be usually expected. Main boiler feed pump has the highest exergy efficiency, which is equal to 87.00%, at power plant nominal load, while the highest exergy efficiency of condensate extraction pump (95.77%) was observed at 60% of power plant nominal load. The influence of the ambient temperature on both pumps exergy efficiencies and losses is almost negligible.

Keywords

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