Repository logo
  • Log In
    Log in via Symplectic to deposit your publication(s).
Repository logo
  • Communities & Collections
  • Research Outputs
  • Statistics
  • Log In
    Log in via Symplectic to deposit your publication(s).
  1. Home
  2. Faculty of Engineering
  3. Faculty of Engineering
  4. Intermittent waste heat recovery via ORC in coffee torrefaction
 
  • Details
Intermittent waste heat recovery via ORC in coffee torrefaction
File(s)
1-s2.0-S1876610217363105-main.pdf (1 MB)
Published version
Author(s)
Pantaleo, AM
Fordham, J
Oyewunmi, OA
Markides, CN
Type
Conference Paper
Abstract
Coffee torrefaction is carried out by means of hot air at average temperature of 200-240°C and with intermittent cycles where a lot of heat is discharged from the stack. CHP systems have been investigated to provide heat to the process. However, much of the heat released in the process is from the afterburner that heats up the flue gas to higher temperatures to remove volatile organic compounds and other pollutants. In this paper, the techno-economic feasibility of utilising waste heat from a rotating drum coffee roasting with partial hot gas recycling is assessed. A cost analysis is adopted to compare the profitability of two systems configurations integrated into the process. The case study of a major coffee torrefaction firm with 500 kg/hr production capacity in the Italian energy framework is taken. The CHP options under investigation are: (i) regenerative topping micro gas turbine (MGT) coupled to the existing modulating gas burner to generate hot air for the roasting process; (ii) intermittent waste heat recovery from the hot flue gas through an organic Rankine cycle (ORC) coupled to a thermal storage buffer. The results show that the profitability of these investments is highly influenced by the natural gas/electricity cost ratio, by the coffee torrefaction production capacity and intermittency level of discharged heat. In this case study, MGT seems to be more profitable than waste heat recovery via ORC due to the intermittency of the heat source and the relatively high electricity/heat cost ratio.
Date Issued
2017-12
Date Acceptance
2017-08-21
Citation
Energy Procedia, 2017, 142, pp.1714-1720
URI
http://hdl.handle.net/10044/1/64059
DOI
https://www.dx.doi.org/10.1016/j.egypro.2017.12.554
ISSN
1876-6102
Publisher
Elsevier
Start Page
1714
End Page
1720
Journal / Book Title
Energy Procedia
Volume
142
Copyright Statement
© 2017 The Authors. This is an open access article published under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0 - https://creativecommons.org/licenses/by-nc-nd/4.0/)
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/P004709/1
Source
9th International Conference on Applied Energy, ICAE2017
Publication Status
Published
Start Date
2017-08-21
Finish Date
2017-08-24
Coverage Spatial
Cardiff, UK
Date Publish Online
2018-01-31
About
Spiral Depositing with Spiral Publishing with Spiral Symplectic
Contact us
Open access team Report an issue
Other Services
Scholarly Communications Library Services
logo

Imperial College London

South Kensington Campus

London SW7 2AZ, UK

tel: +44 (0)20 7589 5111

Accessibility Modern slavery statement Cookie Policy

Built with DSpace-CRIS software - Extension maintained and optimized by 4Science

  • Cookie settings
  • Privacy policy
  • End User Agreement
  • Send Feedback