Performance of Derna Steam Power Plant at Varying Super-Heater Operating Conditions Based on Exergy
Authors: Idris Elfeituri
In the current study, energy and exergy analysis of a 65 MW steam power plant was carried out. This study investigated the effect of variations of overall conductance of the super heater on the performance of an existing steam power plant located in Derna, Libya. The performance of the power plant was estimated by a mathematical modelling which considers the off-design operating conditions of each component. A fully interactive computer program based on the mass, energy and exergy balance equations has been developed. The maximum exergy destruction has been found in the steam generation unit. A 50% reduction in the design value of overall conductance of the super heater has been achieved, which accordingly decreases the amount of the net electrical power that would be generated by at least 13 MW, as well as the overall plant exergy efficiency by at least 6.4%, and at the same time that would cause an increase of the total exergy destruction by at least 14 MW. The achieved results showed that the super heater design and operating conditions play an important role on the thermodynamics performance and the fuel utilization of the power plant. Moreover, these considerations are very useful in the process of the decision that should be taken at the occasions of deciding whether to replace or renovate the super heater of the power plant.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1129584Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 835
 Derna Power Plant Working Documents, 1980, Turbine and Boiler Units, Brown Boveri, Vol. 4.
 Szargut, J., Morris, R., and Steward, F., 1988, Exergy Analysis of Thermal, Chemical and Metallurgical Processes, First Edition, Hemisphere Publishing, New York.
 Gaggioli, R., and Fehring T., 1977,"Economics of feedwater Heater replacement," ASMA Journal of Engineering for Power, Vol. 112, pp. 482-489.
 Lior, N., 1996," Energy, Exergy and Thermo-economic Analysis of the Effects of Fossil-Fuel Superheating in Nuclear Power plant," ECOS, Stockholm, pp. 669-674.
 Benyo, I., et al., 2004,"Modelling of Steam Temperature Dynamics of a Superheater," Proceeding 16th European Simulation Symposium, Finland, pp. 286-290.
 Suresh, M., et al.,2004,"Energy and Exergy Based Thermodynamic Analysis of a 62.5 MWe Coal-Based Thermal Power Plant- A Case Study," Int. Conference on Energy and Environment, Malaysia, pp. 1-6.
 Srinivas, T. et al., 2007, "Generalized Thermodynamic analysis of Seam Power Cycles with 'n' Number of Feedwater Heaters," Int. J. of Thermodynamics, Vol. 10, pp. 177-185.
 Bhatt, M. and Rajkumar, N., 1999," Performance Enhancement in Coal Fired Thermal Power Plants, Part II: Steam Turbines, Int. J. of Energy Research, Vol. 23, pp. 489-515.
 Ronsen, M. and Raymond, T., 2006, "Assessing and Improving the Efficiencies of a Steam Power Plant using Exergy Analysis part I: assessment", Int. J. of Exergy, vol. 3(4), pp. 362-376.
 Szargut, J., 2005,"Influence of Regenerative Feedwater Heaters on the Operational Costs of Steam Power Plants and HP Plants", Int. J. of Thermodynamics, Vol. 8(3), pp. 137-141.
 Elfeituri A. I., "The Influence of Feed water Heaters Operation Conditions on the Exergy Loss and Economic Effects of a Steam Power Plant" PhD Thesis, Warsaw Technical University, Poland, (1997).
 Cengel, Y. A., 1997, Introduction to Thermodynamics and Heat Transfer, McGraw-Hill, New York.