Combustion behavior of algal biomass: carbon release, nitrogen release, and char reactivity
Date
2014
Authors
Lane, D.
Ashman, P.
Zevenhoven, M.
Hupa, M.
Van Eyk, P.
De Nys, R.
Karlström, O.
Lewis, D.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Energy & Fuels, 2014; 28(1):41-51
Statement of Responsibility
Daniel J. Lane, Peter J. Ashman, Maria Zevenhoven, Mikko Hupa, Philip J. van Eyk, Rocky de Nys, Oskar Karlström, and David M. Lewis
Conference Name
Abstract
Recent focus on algae biomass as an alternative energy source can be attributed to building pressure for conservation of dwindling fossil fuels and reduced greenhouse gas emissions. Both micro- and macroalgae have many advantages over terrestrial plants, including typically faster growth rates and, therefore, higher rates of carbon fixation. This paper reports the combustion characteristics of a species of microalgae and two species of macroalgae under conditions that are relevant for the large-scale use of biomass for heat and other products. The tested species were Tetraselmis sp. (marine microalgae), Derbersia tenusissima (marine macroalgae), and Oedogonium sp. (freshwater macroalgae). Two variants of Oedogonium were tested. One variant was cultivated using standard nutrient additions, and the other variant was starved of essential nutrients. Carbon conversion to CO and CO2 and the release of N as NO were determined for the algae by oxidizing fixed-bed samples of each alga in air at 800 and 1000 °C. The gasification reactivity of the chars was also characterized by gasifying samples of each alga in a thermobalance in pure CO2 (1 atm) at 800 °C, following in situ devolatilization of the algal samples. Carbon conversion to CO and CO2 exceeded 84% for all of the tested algae. Most of the fuel C was released during fuel devolatilization, consistent with the proximate analysis for these fuels. Nitrogen conversions to NO ranged between 6 and 12 g of N/100 g of fuel N for Tetraselmis, 6–9 g of N/100 g of fuel N for Derbersia, and 11–21 g of N/100 g of fuel N for the two Oedogonium variants, with NO emissions occurring mainly during devolatilization, in most cases. Chars produced from samples of macroalgae were much more reactive than the chars from the microalgae, most likely because of the inhibitory effects on mass transfer caused by the very high ash content of the sample used in the present study. The reactivities of all chars increased at high char conversions.
School/Discipline
Dissertation Note
Provenance
Description
Publication Date (Web): October 23, 2013
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Rights
© 2013 American Chemical Society