COMPARATIVE ENERGY AND EXERGY ANALYSIS OF A POWER PLANT WITH SUPER-CRITICAL AND SUB-CRITICAL

The aim of this study that how to effect live steam parameters reheat and feed water preheater numbers on efficiencies of energy and exergy at coal-fired power plants. Moreover, two desuperheaters and a regenerative turbine are added USCPP (Case 3) to approach best results. Soma Power Plant (Case 1) consists of one reheat stage, two HPRHs and four LPRHs with one DEA. It is operated sub-critic and coal is used for a fuel. Live steam conditions of Soma Power Plant set at 13,92 MPa and 540 °C, and the reheat steam is reheated to 540 °C. Supercritical Power Plant (Case 2) consists of the same main components of Case 1. However, steam parameters of Case 2 are increased to 262.5 Bar and 600 °C to determine impact of the steam parameters on power plant efficiencies. USCPP which consists of two reheat stages, four HPRHs, six LPRHs with one DEA is designed to generate live steam under nominal conditions of 30 Bar and 600 °C. Besides, reheat steam are heated to 620 °C. Simulations have been carried out Ebsilon Professional software and pressure drops at preheaters and reheats are also considered. Some assumptions are made in the analysis. The thermal and exergy efficiencies of USCPP increase by 9.241 and 8.06 percentage points compared with Soma power plant, respectively. The results of this study that live steam parameters which are increased from sub-critical values to super-critical values have enormous influence on energy and exergy efficiencies. Secondly, adding second reheat stage has positive impact to improve power plant efficiencies. Finally, augmenting feed water preheater number, adding two desuperheater and one regenerative turbine increase power plant efficiencies. However, optimum numbers of feed water preheaters are determined considering economic parameters.

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  • [1] Sayin, C., Nisa Mencet, M., Ozkan, B. (2005). Assessing of Energy Policies Based on Turkish Agriculture:Current Status and Some Implications, Energy Policy, 332361-2373.
  • [2] International Energy Agency. World Energy Outlook. (2014).
  • [3] Adibhatla, S., Kaushik, S.C. (2014). Energy and Exergy Analysis of a Super Critical Thermal Power Plant at Various Load Conditions Under Constant and Pure Sliding Pressure Operation. Applied Thermal Engineering, 73, 51-65.
  • [4] Utlu, Z. Hepbasli, A. (2007). Assessment of the Turkish Utility Sector Through Energy and Exergy Analyses. Energy Policy 35, 5012-5020.
  • [5] Erdem, H.H., Akkaya, A.V., Cetin, B., Dagdaş, A., Sevilgen, S.H., Sahin, B., Teke, I., Gungor, C., Atas, S. (2009). Comparative Energetic and Exergetic Performance Analyses for Coal-Fired Thermal Power Plants in Turkey. International Journal of Thermal Sciences 48, 2179-2186.
  • [6] Xu, G., Zhou, L., Zhao, S., Liang, F., Xu, C., Yang, Y. (2015). Optimum Superheat Utilization of Extraction Steam in Double Reheat Ultra-Supercritical Power Plants. Applied Energy 160, 863-872.
  • [7] Rashidi, M.M., Aghagoli, A., Ali, M. E. (2014). Thermodynamic Analysis of a Steam Power Plant with Double Reheat and Feed Water Heaters. Advances in Mechanical Engineering.
  • [8] Aljundi, I.H. (2009). Energy and Exergy Analysis of a Steam Power Plant in Jordan. Applied Thermal Engineering 29, 324-328.
  • [9] Doseva, N., Chakyrova, D. (2015). Exergy and Energy Analysis of Cogeneration System With Biogas Engines. Journal of Thermal Engineering, 1(3), 391-401.
  • [10] Luo, Y., Woolley, E. (2015). Improving Energy Efficiency Within Manufacturing by Recovering Waste Heat Energy. Journal of Thermal Engineering, 1(1), 337-344.
  • [11] Karakurt, A.S., Güneş, Ü. (2017). Performance Analysis of A Steam Turbine Power Plant at Part Load Conditions. Journal of Thermal Engineering, 3(2), 1121-1128.
  • [12] Akkaya, A.V. (2017). Performance Analyzing of An Organic Rankine Cycle Under Different Ambient Conditions. Journal of Thermal Engineering, 3(5), 1498-1504.
  • [13] Özdil, N.F., Tantekin, A., Pekdur, A. (2018). Performance Assessment of A Cogeneration System in Food Industry. Journal of Thermal Engineering, 4(2), 1847-1854.
  • [14] Oktay, Z. (2009). Investigation of Coal-Fired Power Plants in Turkey and a Case Study: Can Plant. Applied Thermal Engineering 29, 550-557.
  • [15] Kaushik, S.C., Kumar, R. Arora, R. (2016). Thermo-economic Optimization and Parametric Study of an Iirreversible Regenerative Brayton Cycle. Journal of Thermal Engineering, 2, 861-870.
  • [16] Kumar, R., Kaushik, S. C., Kumar, R. (2015). Performance Analysis of an Irreversible Regenerative Brayton Cycle Based on Ecological Optimization Criterion. International Journal of Thermal & Environmental Engineering, 9, 25-32.
  • [17] Aroro, R., Kaushik, S.C., Kumar, R. (2015). Performance Analysis of Brayton Heat Engine at Maximum Efficient Power Using Temperature Dependent Specific Heat of Working Fluid. Journal of Thermal Engineering, 1, 345-354.
  • [18] Kaushik, S.C., Manikandan, S., Hans, R. (2016). Energy and Exergy Analysis of an Annular Thermoelectric Heat Pump. Journal of Electronic Materials, 45, 3400-3409.
  • [19] Kaushik, S.C., Manikandan, S., Hans, R. (2015). Energy and Exergy Analysis of Thermoelectric Heat Pump System. International Journal of Heat and Mass Transfer, 86, 843-852.
  • [20] Li, Y., Zhou, L., Xu, G., Zhao, S., Yang, Y. (2014). Thermodynamic Analysis and Optimization of a Double Reheat System in an Ultra-Supercritical Power Plant. Energy, 74, 202-214.
  • [21] Suresh, M. V. J. J., Reddy, K. S., Kolar, A. K. (2011). Thermodynamic Optimization of Advanced Steam Power Plants Retrofitted for Oxy-Coal Combustion. Journal of Engineering for Gas Turbines and Power 133.
  • [22] Cengel, Y.A., Boles, M.A. 2008. Thermodynamic an Engineering Approach, Fifth Edition.
  • [23] Tekel, E. (2006). Termik Santrallerin Enerji ve Ekserji Analizi, Pamukkale Üniversitesi. Denizli.
  • [24] Vardar, N., Yumurtaci, Z. (2010). Emissions Estimation for Lignite-Fired Power Plants in Turkey. Energy Policy, 38, 243-252.
  • [25] STEAG Energy Services Gmbh. Ebsilon Professional. 2010.
  • [26] Espatolero, S., Romeo, L. M., Cortes, C. (2014). Efficiency Improvement Strategies for the Feedwater Heaters Network Designing in Supercritical Coal-Fired Power Plants. Applied Thermal Engineering, 73, 449-460.
  • [27] Drbal, L.F., Boston, P. G., Westra, K. L., Erickson, R. B. (1996). Power Plant Engineering by Black&Veatch.
  • [28] Zhou, L., Xu, G., Zhao, S., Xu, C., Yang, Y. (2016). Parametric Analysis and Process Optimization of Steam Cycle in Double Reheat Ultra- Supercritical Power Plants. Applied Thermal Engineering, 99, 652-660.