Influence of Feedstock on the Release of Potassium, Sodium, Chlorine, Sulfur, and Phosphorus Species during Gasification of Wood and Biomass Shells

The objective of this work was to investigate the influence of feedstock on the release of trace elements during gasification. Therefore, different types of woody biomass and biomass residues (shells) were thermochemically converted in an atmospheric flow channel reactor furnace at different temperatures (900, 1200, and 1400 degrees C) under gasification-like conditions. For the determination of the composition of the hot gas, the flow channel reactor was coupled to a molecular beam mass spectrometer. The focus was set on the release of alkali metals (K and Na) and non-metals (S, Cl, and P), which are known for their high volatility and influence on the solid- and gas-phase chemistries, as well as the volatility of the other elements. The main gaseous species were (HCl+)-H-36, (NaCl+)-Na-58, (KCl+)-K-74, (SO2+)-S-64, (COS+)-C-64, and (PO2+)-P-63. After quantification, the data set was correlated with the elemental composition of the biomass and likely release mechanisms are discussed.