Oxy-fuel Combustion of Wheat Straw Pellets in a Lab-Scale Fluidized Bed Combustor
This paper presents an experimental study on agro biomass pellets combustion in a circulating fluidized bed (CFB) under three oxy-fuel conditions (21%O2/79%CO2, 30%O2/70%CO2 and 40%O2/60%CO2) and air–fuel condition. The combustion of wheat straw pellets was conducted at a temperature of 850 °C in a 12 kW lab-scale CFB combustor. The main objective of this study was to investigate the combustion behaviour of wheat straw, in terms of particle temperature profiles, ignition time, volatiles combustion time and burnout time. The results of the tests show that the composition of the oxidizing atmosphere highly influences the combustion process of biomass fuels. Replacing N2 in the combustion environment by CO2 caused slight delay in the combustion of wheat straw pellets. The combustion process in O2/CO2 mixtures at 30 and 40% O2 is faster and shorter than that at lower O2 concentrations.
KeywordsBiomass Oxy-combustion Agricultural residues Pellet CFB
This work was financially supported by the National Science Centre (Poland) on the basis of the decision No. DEC-2012/07/B/ST8/03730. The support is gratefully acknowledged.
- 1.Suri, A., Horio, M.: Solid biomass combustion. In: Lackner, M., Winter, F., Agarwal. A.K. (eds.) Handbook of Combustion. Solid Fuels, vol. 4, pp. 85–140. Wiley-VCH (2010)Google Scholar
- 2.Loo, S., Koppejan, J.: The Handbook of Biomass Comb. and Co-firing. Routledge (2008)Google Scholar
- 3.Obernberger, I., Thek, G.: The Pellet Handbook. The Production and Thermal Utilisation of Biomass Pellets. Routledge (2012)Google Scholar
- 6.Preto, F.: Strategies and techniques for combustion of agricultural biomass fuels. In: Growing the Margins Energy Conference (2007)Google Scholar
- 7.Eurostat. http://ec.europa.eu/eurostat
- 8.Natunen, M., Jäntti, T., Goral, D., Nuortimo, K.: First operating experiences of 55 MWe Konin and 205 MWe Połaniec CFB Boilers Firing 100% Biomass. PowerGen Europe (2013)Google Scholar
- 9.Magdziarz, A., Gajek, M., Nowak-Woźny, D., Wilk, M.: Mineral phase transformation of biomass ashes—experimental and thermochemical calculations. Renew. Energy (2017). https://doi.org/10.1016/j.renene.2017.05.057
- 10.Steenari, B.M., Lundberg, A., Pettersson, H., Wilewska-Bien, M., Andersson, D.: Investigation of ash sintering during combustion of agricultural residues and the effect of additives. Energy & Fuels 23, 5655–5662 (2009)Google Scholar
- 15.Gulyurtlu, I., Teixeira, P., Lopes, H., Lapa, N., Freire, M., Galhetas, M., Cabrita, I.: Prediction of slagging and fouling tendency of biomass co-firing in fluidized bed combustion. In: Werther, J., Nowak, W., Wirth, K.-M., Hartge, E.-U. (eds.) CFB-9: Circulating fluidized bed Technology IX: Proceeedings of the 9th International Conference on Circulating Fluidized Beds in conjunction with the 4th International VGB Workshop “Operating experience with Fluidized bed-firing systems”, p. 6. Hamburg, Germany, May 13–16, (2008) Google Scholar