Extractability of Heavy Metals in Cyclone Ash

Raskmetallide ekstraheeritavus tsüklontuhast

Risto Pöykiö ； Hannu Rönkkömäki ； Hannu Nurmesniemi ； Toomas Tenno ； Lilli Paama

《Proceedings of the Estonian Academy of Sciences》 57卷2期 (2008/06) Pp. 100-106

並列摘要

Landfill disposal is the only reasonable option for cyclone ash due to its elevated concentrations of the heavy metals Cd (25 mg kg^(-1); d. w.), Zn (3630 mg kg^(-1); d. w.), Ba (4260 mg kg^(-1); d. w.), and Hg (1.7 mg kg^(-1); d. w.). The distribution of heavy metals (i.e. Cd, Cu, Pb, Cr, Zn, As, V, and Ba) after a three-stage BCR sequential extraction procedure between the exchangeable (CH3COOH), easily reduced (NH2OH-HCl), and oxidizable (H2O2+CH3COONH4) fractions showed that the highest concentrations of most of the heavy metals occurred in the oxidizable fraction. This indicates that a major part of the heavy metals retained in the cyclone ash originating from a small-scale (6 MW) municipal district heating plant incinerating forest residues (i.e. wood waste and bark) are not easily liberated under the conditions normally found in nature.

並列關鍵字

environmental research ； air pollution ； ash ； cyclone ； extraction ； heavy metals ； waste