THERMAL SCIENCE

International Scientific Journal

EXERGOECONOMIC EVALUATION OF REAL PROCESSES FOR COFFEE ROASTING

ABSTRACT
Exergoeconomic methods provide an effective approach for identifying, evaluating and reducing thermodynamic inefficiencies and costs in an energy system. The aim of this paper is to show the potential for cost reduction on the demand side, using the exergoeconomic method in the example of real processes for coffee roasting. More than 6.5·109 kg of coffee beans is roasted worldwide annually, mostly in batch roasters. Near the end of the roast, roasting coffee emits volatile organic compounds, carbon monoxide and other pollutants, which in many industrialized countries have to be oxidized in afterburners. Afterburners release exhaust gases with a temperature of 250-450 °C, depending on the roasting process and the method of exhaust gas cleaning. The aim of this paper is to use exergy analysis and exergoeconomic performance evaluation to determine the energy use for coffee roasting and the afterburning process, and evaluate the way to utilize waste heat and reduce costs in the factory. For roasters with the capacity of up to 4 tons of green coffee beans per hour, the potential of heat recovery is 1.1 MW and the possibility to save money is around 60,000 € per year. This case study is similar to many others worldwide, and the results of this analysis could lead to more general conclusions.
KEYWORDS
PAPER SUBMITTED: 1970-01-01
PAPER REVISED: 2016-08-03
PAPER ACCEPTED: 2016-10-22
PUBLISHED ONLINE: 2016-12-25
DOI REFERENCE: https://doi.org/10.2298/TSCI16S5271V
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2016, VOLUME 20, ISSUE Supplement 5, PAGES [S1271 - S1283]
REFERENCES
  1. ****, Blog to Save Energy, www.ase.org/, accessed Feb., 25, 2016
  2. Fabbri, A., et al., Numerical Modeling of Heat and Mass Transfer during Coffee Roasting Process, J. of Food Eng., 105 (2011), 2, pp. 264-269
  3. Eggers, R., Pietsch, A., Roasting, in: Coffee: Recent Developments (Eds. R. J. Clark, O. G. Vitzhnem), pp. 90-107, Blackwell Science, London, 2001
  4. Severini, C., et al., Influence of Heating Rate on some Physical Physico-Chemical Properties of Coffee Beans, Proceedings, 14th Int. Sci. Colloquium on Coffee, 1992, ASIC, San Francisco, Cal., USA, pp. 641-648
  5. Schwartzberg, H., Batch Coffee Roasting; Roasting Energy Use; Reducing that Use, in: Advanced in Food Process Engineering Research and Applications, (Eds. Yanniotis, S., et al.), Food Engineering Series, Springer Science+Business Media, New York, USA, pp. 173-195, 2013
  6. Monte, D. M., et al., Waste Heat Recovery in a Coffee Roasting Plant, Applied Thermal Engineering, 23 (2003), 8, pp. 1033-1044
  7. Vučković, G., Examination of Energy Efficiency of a Complex Energy Plant by Applying the Method of Exergoeconomics (in Serbian), Ph. D. thesis, Faculty of Mechanical Engineering, Nis, Serbia, 2013
  8. Korenous, J. C., et al., Exergy Analysis of a 300 MW Lignite Thermoelectric Power Plant, Energy, 75 (2014), Oct., pp. 304-311
  9. Gungor, A., et al., Advanced Exergoeconomic Analysis of a Gas Engine Heat Pump (GEHP) for Food Drying Processes, Energy Conv. and Manage., 91 (2015), Feb., pp. 132-139
  10. Erbay, Z., Hepbasli, A., Application of Conventional and Advanced Exergy Analyses to Evaluate the Performance of a Ground-Source Heat Pump (GSHP) Dryer Used in Food Drying, Energy Conv. and Manage., 78 (2014), Feb., pp. 499-507
  11. Tsatsaronis, G., et al., Understanding the Thermodynamic Inefficiencies in Combustion Processes, Energy, 62 (2013), Dec., pp. 3-11
  12. Vučković, G., et al., Advanced Exergy Analysis and Exergoeconomic Performance Evaluation of Thermal Processes in an Existing Industrial Plant, Energy Conv. and Manage., 85 (2014), Sep., pp. 655-662
  13. Guertuerk, M., et al., Comparison of Exergoeconomic Analysis of Two Different Perlite Expansion Furnaces, Energy, 80 (2015), Feb., pp. 589-598
  14. Sayadi, S., et al., Exergoeconomic Analysis of Vehicular PEM (Proton Exchange Membrane) Fuel Cell Systems with and without Expander, Energy, 77 (2014), Dec., pp. 608-622
  15. Atmaca, A., Yurmrutaş, R., Thermodynamic and Exergoeconomic Analysis of a Cement Plant: Part I - Methodology, Energy Conv. and Manage., 79 (2014), Mar., pp. 790-798
  16. Petrakopoulou, F., et al., Conventional Exergetic and Exergoeconomic Analysis of a Power Plant with Chemical Looping Combustion for CO2 Capture, Int. J. of Thermodynamics, 13 (2010), 3, pp. 77-86
  17. Tumen Ozdil, N. F., Tantekin, A., Exergoeconomic Analysis of a FBCC Steam Power Plant, Thermal Science, on line first, DOI:10.2298/TSCI151210056T
  18. ****, Engineering Equation Solver, www.fchart.com/, accessed May, 25, 2015
  19. Szargut, J., et al., Exergy Analysis of Thermal, Chemical, and Metallurgical Processes, Hemisphere Publ. Corp., New York, USA, 1988
  20. Bejan, A., et al., Thermal Design & Optimization, John Wiley & Sons, Inc., New York, USA, 1996
  21. Kotas, T. J., The Exergy Method of Thermal Plant Analysis, Butterworths, London, 1985
  22. Moran, M., Shapiro, H., Fundamentals of Engineering Thermodynamics, John Wiley & Sons, Ltd., West Sussex, England, 2006

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence