Slow Pyrolysis of Specialty Coffee Residues towards the Circular Economy in Rural Areas

Josefa Fernández-Ferreras (), Tamara Llano, María K. Kochaniec and Alberto Coz
Additional contact information
Josefa Fernández-Ferreras: Department of Chemistry and Process & Resources Engineering, ETSIIT, Universidad de Cantabria, Av. Los Castros, 39005 Santander, Spain
Tamara Llano: Department of Chemistry and Process & Resources Engineering, ETSIIT, Universidad de Cantabria, Av. Los Castros, 39005 Santander, Spain
María K. Kochaniec: Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland
Alberto Coz: Department of Chemistry and Process & Resources Engineering, ETSIIT, Universidad de Cantabria, Av. Los Castros, 39005 Santander, Spain

Energies, 2023, vol. 16, issue 5, 1-21

Abstract: Coffee, as one of the most consumed beverages, generates a wide variety of waste materials that can be used as biofuels and bio-products. Conventional pyrolysis can be used in rural areas, improving the circular bioeconomy of these places. In this work, the characterization and slow pyrolysis of specialty coffee residues, coffee silverskin (CSS), and spent coffee (SC) were conducted at temperatures from 300 to 600 °C. Physico-chemical and thermal analysis were carried out. In addition, the quantification of individual compounds as acetic, formic, and levulinic acids, caffeine, and other minor compounds was performed. The results indicate the differences between both waste materials in the obtained pyrolysis fractions. The biochar fraction for SC is lower at all temperatures and the liquid fraction higher, reaching maximum values of 62 wt.% in the liquid at 600 °C compared to 47% in CSS. The higher yield in the liquid fraction of SC corresponds to the higher contents of hemicellulose and extractives and the lower ash content. The calculated calorific value for the pyrolysis solid fractions reaches 21.93 MJ/kg in CSS and 26.45 MJ/kg in SC. Finally, biorefinery options of major components of the liquid fraction were also presented.

Keywords: biorefinery; circular economy; characterization; slow pyrolysis; coffee silverskin; spent coffee (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/16/5/2300/pdf (application/pdf)
https://www.mdpi.com/1996-1073/16/5/2300/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:16:y:2023:i:5:p:2300-:d:1082465

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().