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Doctoral defence of Sandra Sandar, MSc, 18 Feb 2022: Potential of neglected biomass and industrial side-streams utilization in biofuels production

The doctoral dissertation in the field of Forestry will be examined at the Faculty of Science and Forestry online.

What is the topic of your doctoral research?

The unrecognized locally abundant biomass and forest industrial side-streams is utilized for biofuels production through biochemical, thermochemical, and combined bio- and thermo-chemical conversion technologies. The biofuel production from the rarely characterized forest side-streams such as lake bottom biomass and pulp and paper mill sludges from different stages of the pulping process makes them a potential utilization of the substances in the biorefinery industries.

What are the key findings or observations of your doctoral research?

The ash of both eutrophic and mesotrophic lake bottom biomass could be used as soil improvement, and fertilizer in forestry and eutrophic lake biomass produced the potential ethanol yield from fermentation. The rejects from pre-hydrolysis stage side-stream (PI) and primary sludge (PII) were prospective substrates for butanol and ethanol production, respectively. Our findings indicate that lake bottom biomass can be considered a potential non-food lignocellulosic source. The cost-competitive ethanol selling price of primary sludge from an integrated gasification-syngas fermentation process provides the Finnish policymakers and researchers not to overlook bioethanol production from pulp and paper process side-streams for the biorefining industry.

How can the results of your doctoral research be utilised in practice?

Biofuel production from an integrated gasification-syngas fermentation operations unit or ABE fermentation unit can be installed close to a Kraft pulp mill by utilizing the different pulp side-streams and creating additional revenues for mill owners.

What are the key research methods and materials used in your doctoral research?

Forest side-streams such as eutrophic and mesotrophic lake bottom biomass and eight pulp and paper manufacturing side-streams from different stages of the pulping process were utilized for biofuel production. Theoretical biogas and bioethanol productions were modeled by Aspen Plus® simulation through 1) saccharification and fermentation, 2) gasification and mixed alcohol synthesis, 3) gasification-syngas fermentation, and 4) anaerobic digestion processes. Dilute acid 0.2% H2SO4 at 180 oC for 10 min was an efficient pretreatment method in ABE fermentation.

Is there something else about your doctoral dissertation you would like to share in the press release?

The neglected biomass accumulated on the Finnish lake bottom as a new and locally abundant non-food biomass and putting waste back into the production stream in biofuel production in biorefineries is considered a novelty in this research.

The doctoral dissertation of Sandra Sandar, MSc, entitled Potential of neglected biomass and industrial side-streams utilization in biofuels production will be examined at the Faculty of Science and Forestry, at the Joensuu Campus, Agora, AT100, and online, on 18 February at 12 noon. The opponent will be Dr Tom Granström, VTT, and the custos will be Professor Ari Pappinen, University of Eastern Finland. Language of the public defence is English.

For further information, please contact:

Sandra Sandar, sandrs@uef.fi, tel. 046 8808404, Twitter @drmasandr

Public examination online

Dissertation book online 

Photo available for download