浮萍生物质灰分的特性分析

ANALYSIS OF ASH PROPERTIES OF DUCKWEED BIOMASS

利用低温成灰的方法对两种浮萍(紫萍和青萍)进行灰化,测定灰分含量,通过SEM/EDS分析、X射线衍射分析和TGA/DSC分析实验对两种灰分的形貌、成分、热活动等进行对比研究。结果显示:浮萍灰分中碱金属、碱土金属和氯含量高,硅含量低。灰分中KCl含量大,在温度升高时挥发量大,灰分的积灰结渣倾向严重。对于两种浮萍而言,紫萍的积灰结渣倾向重于青萍。这些结果表明在浮萍生物质燃烧和气化利用中应重视碱金属挥发和熔化所带来的积灰结渣问题。

Two species of duckweed-Spirodela and Lemna were burned under low ashing temperature. Ash content was determined. The ash composition and morphology were investigated by SEM/EDS, crystalline phase by XRD, and thermal behavior by TGA/DSC. The results indicated that duckweed ash had a high level of alkali, alkali earth metals and chlorine but a low level of silicon. The KCl content was high and tended to evaporate when temperature rose, the ash deposition and slaging tendency was serious and it was more serious for Spirodela than Lemna. These indicated that much attention should be paid on the ash deposition and slaging problem that might be caused by the alkali melting and evaporation when combustion or gasification of duckweed biomass.