Thermodynamics Performance Evaluation in Combined Cycle Power Plant by Using Combined Pinch and Exergy Analysis

Abstract

In this paper, combination between pinch and exergy analysis for a 326 MW Combined Cycle Power Plant (CCPP) at Tanjung Priok is performed. These cycles are made of a gas turbine, a steam turbine and Heat Recovery Steam Generator (HRSG). In addition to analyze the performance of each component (compressor, combustion chamber, turbine, heat recovery steam generator) of the Combined Cycle Power Plant CCPP Tanjung Priok, this study also analyzes the impact of changes in the operating costs of the power plant after optimizing the parameters (pinch point and steam drum pressure). By using exergy analysis, the initial data used to analyze the performance and identified which components of the system that has the potential to do the performance improvement. The experience-based values for the pressure of the high-pressure and the low-pressure drum are selected and held constant during this step. One of the initial steps taken in the optimization of this system is to determine the optimum temperature difference in the heat exchange process that occurs in heat recovery steam generator (The value for the pinch point is varied in the range of 5 to 40 °C in steps of 0.5 °C). Then, through the developed optimization process, other optimal operating parameters were identified. The optimized combined cycle was compared with the Initial data. The application results of combined pinch and exergy analysis (CPEA) in the power plant showed that the net power could be increased by 2.67% and the exergetic efficiency could be increased from 45.9% to 47.1%.