Assessment of Physical Properties of Densified Alga Residues for Solid Fuel Applications
KuZilati KUSHAARI, Babar AZEEM, Abdul BASIT, Salma NOUH, Trinh Hoai THANH
Abstract. With the development of biodiesel production through the transesterification process, biomass-derived oils have attracted increasing attention as renewable energy sources. Algae has been identified as a promising feedstock; large quantities of algae residue are produced during biodiesel oil extraction however, more than half of the original algal biomass remains as residue after oil extraction, which reduce the economic viability of algae-based biodiesel. These residues still contain significant energy potential that can be converted into valuable products such as biogas, bio-chemicals, and solid fuels. However, most existing waste-to-energy conversion methods are complex, energy-intensive, and costly. This study evaluates densified algal residue (AR) pellets as a solid fuel by characterizing their physical and fuel properties and comparing them with standard coal and common biomass feedstocks. The results indicate that algae residue (AR) is comparable to commonly used biomass feedstocks. The AR exhibits a low moisture content of 13.74 wt%, which falls within the typical range for biomass feedstocks and is slightly higher than that of coal at 9.3 wt%. Its calorific value of 19.11 MJ/kg is approximately 24% lower than that of standard coal at 25.3 MJ/kg, yet remains within the range reported for other biomass materials. Overall, the algae residue pellets demonstrate good physical strength and favorable characteristics for use as a solid fuel.
Keywords
Algae Residues, Algae Waste, Combustion Fuel, Biofuel, Solid Fuel, Biomass Densification
Published online 4/25/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: KuZilati KUSHAARI, Babar AZEEM, Abdul BASIT, Salma NOUH, Trinh Hoai THANH, Assessment of Physical Properties of Densified Alga Residues for Solid Fuel Applications, Materials Research Proceedings, Vol. 64, pp 700-705, 2026
DOI: https://doi.org/10.21741/9781644904091-87
The article was published as article 87 of the book Energy Futures
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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