Comparison of bio-oils derived from crop digestate treated through conventional and microwave pyrolysis as an alternative route for further waste valorization
Year of publication
2024
Authors
Diaz Perez, Nidia; Lindfors, Christian; van den Broek, Lambertus A.M.; van der Putten, Jacinta; Meredith, William; Robinson, John
Abstract
<p>A total of 120,000 tonnes per year of crop waste from contaminated land has been used as a feedstock for anaerobic digestion (AD). This produces only around 20% of biogas from the total crop and results in a large amount of digestate with heavy metal content. This crop digestate was analyzed across a calendar year to identify the variation in composition, and any potential high-value components that could be targeted for recovery. The chemical characterization revealed that approximately 65% of this residual waste is lignocellulosic material (20% hemicellulose, 24% cellulose, 24% lignin) and about 10% is ash, with no observable difference across the seasons. Three different pyrolysis technologies were studied with the same crop digestate as alternative route to maximize the value of this solid residue by transforming this lignocellulosic material into further bio-based products. Slow pyrolysis at operating temperatures between 355 and 530 °C resulted in bio-oil yields of 35–46% wt, fast pyrolysis at 460–560 °C produced 36–40% wt, and microwave pyrolysis using a power input of 500 and 700 W generated 8–27% wt from the digestate. Chemical compounds found in these bio-oils were categorized into seven chemical groups: acids, aldehydes and ketones, alcohols, furans, sugars, phenolics, and others. This analytical study opens other scenarios to explore the upgrading of these pyrolytic bio-oils for green product generation from the same waste. Graphical Abstract: (Figure presented.)</p>
Show moreOrganizations and authors
Publication type
Publication format
Article
Parent publication type
Journal
Article type
Original article
Audience
ScientificPeer-reviewed
Peer-ReviewedMINEDU's publication type classification code
A1 Journal article (refereed), original researchPublication channel information
Volume
14
Issue
14
Pages
15739-15754
ISSN
Publication forum
Publication forum level
1
Open access
Open access in the publisher’s service
Yes
License of the publisher’s version
CC BY
Self-archived
No
Other information
Fields of science
Materials engineering; Environmental engineering
Keywords
[object Object],[object Object],[object Object],[object Object],[object Object]
Language
English
International co-publication
Yes
Co-publication with a company
No
DOI
10.1007/s13399-022-03712-6
The publication is included in the Ministry of Education and Culture’s Publication data collection
Yes