Energy And Exergy Assessment of North Refineries Company (NRC) Steam Cycle Based on Air Mass Flowrate of Main Condenser

Abstract

The present work depends on the previous energy and exergy analysis study for a steam cycle of North Refineries Company (NRC)/Baiji, Iraq, which was conducted at real and rated operating loads. After the results of that study are presented, this current study is conducted and aimed to produce the engineering solutions for improving the cycle performance through studying the operational choices that are actually available in the plant as investigating the effect of increasing the air mass flow rate in the main condenser of the cycle. The calculations were done by using the MATLAB program. The results showed that increasing the air mass flow rate or increasing the number of fans in service from 8 to 14 fans will reduce the energy losses in the main condenser and in the cycle. The energy loss reduction can be enhanced in the improvement of the energy efficiency by raising it from 30.11 % to 48.61 % at real load and from 33.49 % to 48.93 % at rated load. On the other hand, the exergy analysis showed that the exergy destructions for the main condenser and for the cycle would decrease if the number of fans increased. This decreasing of exergy destruction in the main condenser will raise the exergy efficiency from 21.95 to 27.06 % at real load and from 21.18 % to 25.45 % at rated load.