Effect of Freshwater Washing Pretreatment on Sargassum muticum as a Feedstock for Biogas Production

John J. Milledge, Birthe V. Nielsen, Manar S. Sadek and Patricia J. Harvey
Additional contact information
John J. Milledge: Faculty of Engineering and Science, Algae Biotechnology Research Group, University of Greenwich, Central Avenue, Chatham Maritime, Kent ME4 4TB, UK
Birthe V. Nielsen: Faculty of Engineering and Science, Algae Biotechnology Research Group, University of Greenwich, Central Avenue, Chatham Maritime, Kent ME4 4TB, UK
Manar S. Sadek: Current Address: Pharmacognosy Department, Faculty of Pharmacy, October University of Modern Sciences and Arts, 6th October City 11787, Egypt
Patricia J. Harvey: Faculty of Engineering and Science, Algae Biotechnology Research Group, University of Greenwich, Central Avenue, Chatham Maritime, Kent ME4 4TB, UK

Energies, 2018, vol. 11, issue 7, 1-14

Abstract: The pretreatment of seaweed by washing in freshwater is often used in seaweed biofuel research studies. However, the effect of washing seaweed prior to anaerobic digestion (AD) does not appear to have been greatly studied. This study examines washing Sargassum muticum with freshwater and its effect on ultimate and proximate analyses, salt content, methane production from anaerobic digestion, and leachate loss from ensiling. Washing with freshwater significantly ( p < 0.01) increased moisture content (unwashed 85.6%, washed 89.1%) but significantly ( p < 0.05) reduced ash (unwashed 32.7% dry weight dw, washed 30.6% dw) and salt content (unwashed ash containing 51.5%, washed 42.5%). The dry biomass higher heating value was significantly ( p < 0.05) increased by washing due to the lower ash content (11.5 to 12.6 kJ g −1 dw). There was no significant change in the protein or lipid content, although washing increased the nitrogen content (3.85–4.77% dw). Washing significantly ( p < 0.05) increased leachate losses during ensiling, with total leachate losses increasing after washing (12.7–25.2%). The methane yield from anaerobic digestion (28 days) was not statistically significantly different ( p > 0.05) between unwashed (0.225 L CH 4 g −1 VS) and washed samples (0.177 L CH 4 g −1 VS). However, washing delayed biomethane production.

Keywords: Sargassum muticum; washing; anaerobic digestion; seaweed; pretreatment; ensiling; macroalgae (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2018
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (7)

Downloads: (external link)
https://www.mdpi.com/1996-1073/11/7/1771/pdf (application/pdf)
https://www.mdpi.com/1996-1073/11/7/1771/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:11:y:2018:i:7:p:1771-:d:156471

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().