Title: Co-Processing Lignocellulosic Biomass and Sewage Digestate by Hydrothermal Carbonisation: Influence of Blending on Product Quality

Authors (6): K. R. Parmar, A. E. Brown, J. M. Hammerton, M. A. Camargo-Valero, L. A. Fletcher, A. B. Ross

Themes: Design (2022)

DOI: 10.3390/en15041418

Citations: 17

Pub type: journal-article

Publisher: MDPI AG

Issue: 4

License: [{"start"=>{"date-parts"=>[[2022, 2, 15]], "date-time"=>"2022-02-15T00:00:00Z", "timestamp"=>1644883200000}, "content-version"=>"vor", "delay-in-days"=>0, "URL"=>"https://creativecommons.org/licenses/by/4.0/"}]

Publication date(s): 2022/02/15 (online)

Pages: 1418

Volume: 15 Issue: 4

Journal: Energies

Link: [{"URL"=>"https://www.mdpi.com/1996-1073/15/4/1418/pdf", "content-type"=>"unspecified", "content-version"=>"vor", "intended-application"=>"similarity-checking"}]

URL: http://dx.doi.org/10.3390/en15041418

Hydrothermal carbonisation (HTC) can be integrated with anaerobic digestion (AD) for the treatment of digestate, resulting in a solid hydrochar or bio-coal and a process water, which can be recirculated back into AD to produce biogas. The properties of digestate-derived hydrochars do not lend themselves to producing high quality bio-coal and blending with lignocellulosic feedstocks can improve its properties. This study investigates the co-processing of sewage sludge (SS) digestate with three lignocellulosic biomass (grass, privet hedge, and woodchip). The calorific value of the resulting bio-coal is increased following co-processing, although feedstock interactions result in non-additive behaviour. The largest increase in calorific value was observed for co-processing with woodchip. There is evidence for non-additive partitioning of metals during co-processing resulting in only moderate improvements in ash chemistry during combustion. Co-processing also effects the composition of process waters, influencing the potential for biogas production. Experimental biomethane potential (BMP) tests indicate that grass clippings are the most suitable co-feedstock for maintaining both calorific value and biogas production. However, above 200 °C, BMP yields appear to decrease, suggesting the process water may become more inhibitory. Co-processing with wood waste and privet hedge produce the higher CV bio-coal but significantly reduced BMP.

There are no objects associated to this publication