Energy and Economic Analysis of Heat Recovery from Boiler Exhaust Flue Gas
In this study, the potential of heat recovery from waste flue gas was examined in 60 MW district heating system of a university, and fuel saving was aimed by using the recovered heat in the system as a source again. Various scenarios are intended to make use of waste heat. For this purpose, actual operation data of the system were taken. Besides, the heat recovery units that consist of heat exchangers such as flue gas condensers, economizers or air pre-heaters were designed theoretically for each scenario. Energy analysis of natural gas-fired boiler’s exhaust flue gas in the system, and economic analysis of heat recovery units to predict payback periods were done. According to calculation results, the waste heat loss ratio from boiler flue gas in the system was obtained as average 16%. Thanks to the heat recovery units, thermal efficiency of the system can be increased, and fuel saving can be provided. At the same time, a huge amount of green gas emission can be decreased by installing the heat recovery units.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1124125Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2190
 Y. Wang, Q. Zhao, Q. Zhou, Z. Kang and W. Tao, Experimental and numerical studies on actual flue gas condensation heat transfer in a left-right symmetric internally finned tube, International Journal of Heat and Mass Transfer 64 (2013) 10-20.
 C. T. Yucer and A. Hepbasli, Thermodynamic analyses of a building using exergy analysis method, Energy and Buildings 43 (2011) 536-542.
 M. Osakabe, K. Ishida, K. Yagi, T. Itoh and K. Ohmasa, Condensation heat transfer on tubes in actual flue gas, Heat Transfer-Asian Research 30 (2) (2001) 139- 151.
 M. Cortina, Flue gas condenser for biomass boilers, MSc Thesis, Lulea University of Technology, 2006.
 Y. Yang, C. Xu, G. Xu, Y. Han, Y. Fang and D. Zhang, A new conceptual cold-end design of boilers for coal-fired power plants, Energy Conversion and Management 89 (2015) 137-146.
 T.A. Butcher and W. Litzke, Condensing economizers for small coal- fired boilers and furnaces, New York, 1994.
 E. Levy, H. Bilirgen, K. Jeong, M.J. Kessen, C. Samuelsen and C. Whitcombe, Recovery of water from boiler flue gas, Final Technical Report, Lehigh University, Energy Research Center, Bethlehem, 2008.
 J.M. Hill, Study of low-grade waste heat recovery and energy transportation systems in industrial applications, Thesis, Alabama University, Department of Mechanical Engineering, Alabama, 2011.
 Q. Chen, K. Finney, H. Li, X. Zhang, J. Zhou, V. Sharifi and J. Swithenbank, Condensing boiler applications in the process industry, Applied Energy 89 (2012) 30- 36.
 T.M. Alkhamis, M.A. Alhusein and M.M. Kablan, Utilization of waste heat from the kitchen furnace of an enclosed campus, Energy Conversion and Management 39 (1998) 1113-1119.
 K. Bhattacharjee, Energy conservation opportunities in industrial waste heat recovery systems, Energy Engineering 107 (2010) 7-13.
 J. Bujak, Mathematical modeling of a steam boiler room to research thermal efficiency, Energy 33 (2008) 1779-1787.
 J. DeFrees, R. Stuckey and J. Foote, Condensing economizers, Ashrae Journal (2007) 16-23.
 R. Saidur, J. U. Ahamed, H.H. Masjuki, Energy, exergy and economic analysis of industrial boilers, Energy Policy 38 (2009) 2188- 2197.
 M. Shekarchian, F. Zarifi, M. Moghavvemi, F. Motasemi and T.M.I. Mahlia, Energy, exergy, environmental and economic analysis of industrial fired heaters based on heat recovery and preheating techniques, Energy Conversion and Management, 71 (2013) 51-61.
 Y.A. Cengel and M.A. Boles, Thermodynamics an engineering approach, Guven Scientific Press, Izmir, Turkey, 2008.
 O. Okka, Theory of engineering economics, problems and solutions, Nobel Press, Ankara, Turkey, 2009.