Effect of hydrothermal carbonization and torrefaction on spent coffee grounds
| dc.contributor.author | Sermyagina, E. | |
| dc.contributor.author | Mendoza, C. | |
| dc.contributor.author | Deviatkin, I. | |
| dc.date.accessioned | 2021-04-12T08:04:46Z | |
| dc.date.available | 2021-04-12T08:04:46Z | |
| dc.date.issued | 2021 | |
| dc.description | Received: February 1st, 2021 ; Accepted: March 28th, 2021 ; Published: April 6th, 2021 ; Correspondence: ekaterina.sermyagina@lut.fi | eng |
| dc.description.abstract | Coffee is one of the most tradable commodities worldwide with the current global consumption of over 10 billion kilograms of coffee beans annually. At the same time, a significant amount of solid residues, which are known as spent coffee grounds (SCG), is generated during instant coffee manufacturing and coffee brewing. Those residues have a high potential in various applications, yet they remain mostly unutilized. The current work presents the experimental comparison of two pretreatment technologies - hydrothermal carbonization (HTC) and torrefaction - for converting SCG into a valuable char. The results showed that low-temperature torrefaction (< 250 °C) has a negligible effect on feedstock properties due to initial pre-processing of coffee beans. However, the energy conversion efficiency of torrefaction at higher temperatures is comparable with that of HTC. The average energy yields for high-temperature torrefaction (> 250 °C) and HTC were on the level of 88%. Devolatilization and depolymerization reactions reduce oxygen and increase carbon contents during both processes: chars after torrefaction at 300 °C and HTC at 240 °C had 23–28% more carbon and 43–46% less oxygen than the feedstock. Both pretreatment methods led to a comparable increase in energy density: the highest HHV of 31.03 MJ kg-1 for torrefaction at 300 °C and 32.33 MJ kg-1 for HTC at 240 °C, which is similar to HHV of anthracite. The results showed that both processes can be effectively used to convert SCG into energy-dense char, even though HTC led to slightly higher energy densification rates. | eng |
| dc.identifier.issn | 1406-894X | |
| dc.identifier.publication | Agronomy Research, 2021, vol. 19, Special Issue 1, pp. 928–943 | eng |
| dc.identifier.uri | http://hdl.handle.net/10492/6414 | |
| dc.identifier.uri | https://doi.org/10.15159/ar.21.023 | |
| dc.rights | Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) ; openAccess | |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/ | |
| dc.subject | biomass pretreatment | eng |
| dc.subject | hydrothermal carbonization | eng |
| dc.subject | torrefaction | eng |
| dc.subject | spent coffee grounds | eng |
| dc.subject | articles | eng |
| dc.title | Effect of hydrothermal carbonization and torrefaction on spent coffee grounds | eng |
| dc.type | Article | eng |
Failid
Originaal pakett
1 - 1 1
Laen...
- Nimi:
- Vol19_S1_Sermyagina.pdf
- Suurus:
- 1.45 MB
- Formaat:
- Adobe Portable Document Format
- Kirjeldus:
- Article