Efthymiopoulos, I;
Hellier, P;
Ladommatos, N;
Kay, A;
Mills-Lamptey, B;
(2018)
Integrated strategies for water removal and lipid extraction from coffee industry residues.
Sustainable Energy Technologies and Assessments
, 29
pp. 26-35.
10.1016/j.seta.2018.06.016.
Preview |
Text
1-s2.0-S2213138817305246-main.pdf - Published Version Download (484kB) | Preview |
Abstract
Spent coffee grounds (SCGs) and roasted defective coffee beans (RDCBs), are a potentially sustainable source for biofuel production if the processing of these residues, and the recovery of energy-dense lipids, can be undertaken in an energy efficient way. A necessary step in solvent extraction of lipids is prior drying of the feedstock, and this can incur a significant energy cost in the case of SCGs. This study investigates solvent extraction strategies for crude lipid recovery from wet or partially dried SCG samples, with mechanical pressing used as pre-treatment and alternative to thermal drying. Dewatering of SCGs by application of pressures up to 550 bars removed 42% of the moisture present, while lipid expression from whole RDCBs was achieved, with a maximum crude lipid recovery of 77.1% relative to available oil obtained. Crude extracts removal from partially wet pressed SCGs through accelerated solvent extraction (ASE) with ethanol was not impeded by moisture presence, and the obtained extracts had high energy density (∼39 MJ/kg) comparable to hexane-extracted crude lipids. SCG and RDCB crude oil removed through solvent extraction and mechanical pressing respectively had similar fatty acid (FA) compositions, but a higher proportion of free fatty acids (FFAs) in solvent-extracted oil.
Type: | Article |
---|---|
Title: | Integrated strategies for water removal and lipid extraction from coffee industry residues |
Open access status: | An open access version is available from UCL Discovery |
DOI: | 10.1016/j.seta.2018.06.016 |
Publisher version: | https://doi.org/10.1016/j.seta.2018.06.016 |
Language: | English |
Additional information: | This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ |
Keywords: | Coffee residues, Spent coffee grounds, Wet biomass, Solvent extraction, Mechanical expression |
UCL classification: | UCL UCL > Provost and Vice Provost Offices UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Mechanical Engineering |
URI: | https://discovery-pp.ucl.ac.uk/id/eprint/10053196 |
Archive Staff Only
View Item |