Exergy and Energy Analysis of the Steam Power Plant in Isfahan Refinery in Iran

In this paper, the power plant cycle of Isfahan refinery with the capacity of 64 MW was discussed and irreversibility percentage and exergy efficiency were calculated for cycle component using exergy, energy and mass balance equations. Also, the results obtained from exergy analysis introduced boiler as the most important factor for exergy destruction. Increasing feed water temperature has a significant effect on the decrease of exegy loss; therefore, there have been suggestions for increasing the feed water temperature. Considering the calculations conducted in this paper, per 20ºC increase in feed water temperature, there was 0.6% increase in the exergetic efficiency of the cycle and 0.4% increase in the boiler’s exergetic efficiency; also, assuming the fuel price of 0.198 /$kg, there was 520000 /$year economic saving.