Lorente, Almudena, Remón, Javier orcid.org/0000-0003-3315-5933, Budarin, Vitaliy L. et al. (3 more authors) (2019) Analysis and optimisation of a novel “bio-brewery” approach : Production of bio-fuels and bio-chemicals by microwave-assisted, hydrothermal liquefaction of brewers’ spent grains. Energy Conversion and Management. pp. 410-430. ISSN 0196-8904
Abstract
This work firstly explores the feasibility of using a novel microwave-assisted, catalysed, hydrothermal process for the valorisation of brewers’ spent grains (BSGs), examining the effects of the temperature (180–250 °C), pressure (50–130 bar), reaction time (0–2 h) and catalyst amount (Ni-Co/Al-Mg, 0–0.25 g cat/g biomass). This route turned out to be a very promising approach for the production of bio-fuels (bio-oil and bio-char) and platform chemicals (sugar rich aqueous solutions) in a single unit, helping the development of an innovative bio-refinery around BSGs. The overall conversion and the yields to gas, aqueous fraction and bio-oil varied by 31–68%, 10–33%, 9–48% and 4–14%, respectively. The bio-oil was made up a complex mixture of phenols (0–26%), ketones (0–80%), aldehydes (0–57%), carboxylic acids (0–18%) and nitrogen compounds (0–76%). The proportions of C, H, N and O in the bio-oil varied as follow: 15–61 wt%, 5–10 wt%, 1–6 wt% and 26–77 wt%, respectively, which shifted its higher heating value (HHV) between 9 and 27 MJ/kg. The liquid fraction comprised a mixture of DP > 6 oligosaccharides (67–98 C-wt.%), DP2-6 oligosaccharides (0–10 C-wt.%), saccharides (0.2–7 C-wt.%), carboxylic acids (0–7 C-wt.%) and furans (0–27 C-wt.%). The spent solid after the experiments resembled an energetic like bio-char product, whose proportions of C, H, O and N varied by 35–72 wt%, 4–8 wt%, 1–4 wt% and 18–57 wt% and its HHV shifted between 9 and 32 MJ/kg. The optimisation of the process revealed that using a temperature of 250 °C and a pressure of 125 bar for 2 h, it is possible to convert the original material into high-energy biofuels: (8%) bio-oil (26 MJ/kg) and (35%) bio-char (32 MJ/kg); together with a (31%) saccharide-rich (>99 C-wt.%) aqueous solution, thus converting this process into a very promising approach to achieve an environmentally-friendly and integral valorisation of brewers’ spent grains.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2019 Elsevier Ltd. All rights reserved. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. |
Keywords: | Bio-fuels, Brewers’ spent grains, Hydrothermal processes, Microwave heating, Value-added chemicals |
Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Chemistry (York) |
Depositing User: | Pure (York) |
Date Deposited: | 07 May 2019 15:20 |
Last Modified: | 05 Mar 2024 00:12 |
Published Version: | https://doi.org/10.1016/j.enconman.2019.01.111 |
Status: | Published |
Refereed: | Yes |
Identification Number: | https://doi.org/10.1016/j.enconman.2019.01.111 |
Related URLs: |
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