Technical Analysis of Conversion of A Steam Power Plant to Combined Cycle,Using Two Types of Heavy Duty Gas Turbines

Due to long life of steam power plants in Iran, transformation of steam cycles to combined cycles is under consideration. Bandar-Abbas steam power plant with capacity of 320 MW has been analyzed in this work. This old plant is located near the harbor city of Bandar-Abbas in south of Iran. Exergyanalysis method is used to study the current and the repowered systems. Optimum state of the repowered cycle is also obtained using exergy analysis. In this work, a point by point analysis ofBandar-Abbas steam power plant is performed for different modes of full repowering, using exergyanalysis method. For this purpose, V94.2 and V94.3A gas turbines are used and effect of duct burner is investigated for each case. The results show that at the best repowering mode, power plant efficiency is 34.5% higher than the design efficiency of the current steam plant. Minimum rate of exergy destructionrate is 6711 MW at this mode and the heat rate reduces by 26.6%. According to our results, increasing fuel consumption in duct burner and use of V94.2 gas turbine are not recommended for repowering of Bandar-Abbas power plant

Keywords:

Technical Analysis , Exergy , Steam Power Plant , Full Repowering , Combined Cycle , Gas Turbine , HRSG