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Energy & Fuels 2001, 15, 680-690
Behavior of Chlorine and Enrichment of Risky Elements in Bubbling Fluidized Bed Combustion of Biomass and Waste Assisted by Additives Beatrice Coda,*,† Martti Aho,‡ Roland Berger,† and Klaus R. G. Hein† Institute of Process Engineering and Power Plant Technology, IVD, University of Stuttgart, Pfaffenwaldring 23, 70569 Stuttgart, Germany, and VTT Energy, P.O. Box 1603, 40101 Jyva¨ skyla¨ , Finland Received September 29, 2000. Revised Manuscript Received February 1, 2001
High contents of chlorine and alkalies restrict the use of biomass in energy production. Alkali chlorides vaporize during combustion. Chlorine tends to produce corrosive deposits and unacceptably high emissions of HCl and dioxins. Chlorine recovery and enrichment of Cl, Na, K, Ca, Al, and Si in coarse and fine fly ash were studied experimentally with two electrically stabilized bubbling fluidized bed (BFB) reactors capable of reproducing the particle residence times existing in full-scale BFB plants. Feedstocks were fir (mixture of heartwood and bark), paper sludge, and blends of fir with agricultural waste or plastic waste. Sulfur concentrations of feed components were low (
