Parametric Simulation of Combined Cycle Power Pant: A Case Study

Year 2011, Volume: 14 Issue: 1, 29 - 36, 01.02.2011

T. Srinivas B. V. Reddy A. V. S. S. K. S. Gupta

Abstract

In this work a thermodynamic evaluation has been carried out on an existing actual combined cycle plant (LANCO power plant) having a triple pressure heat recovery steam generator (HRSG). In this case study, an attempt has been made to improve the efficiency of the plant through a parametric study using a thermodynamic model. The compressor pressure ratio is evaluated from the terminal temperature difference at HRSG inlet instead of an initial regular fixation. The low pressure (LP) and the intermediate pressure (IP) in HRSG also evaluated from local flue gas temperatures with minimum temperature difference in heaters without initial fixation. The optimized results obtained at high pressures (HP) of 90 and 200 bar are compared with the design results of the plant. The optimum pressures obtained for deaerator, LP and IP heaters at 200 bar of HP pressure are 3.7, 8.3 and 26.5 bar respectively.

Keywords

Combined cycle; pinch point; thermodynamic analysis; triple pressure.

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