【摘要】 利用激光粒度仪、X射线衍射、扫描电镜等对华南某垃圾焚烧厂不同粒径焚烧飞灰（原灰）矿物相组成和微观形貌进行分析,同时研究其重金属浸出毒性和形态特征。结果表明:焚烧飞灰颗粒均在2 mm以下,<38μm粒径占比达到68.07%;微观结构差异较大,多为不规则的疏松结构。焚烧飞灰主要化学成分为CaO、Na₂O和K₂O,Ca O较多集中在大颗粒飞灰中,而K₂O和Na₂O在小粒径焚烧飞灰中含量更高;主要矿物相为氯化物和含钙矿物,含量随粒径减小而增加。焚烧飞灰重金属浸出毒性较低,仅Cr浸出浓度超出GB 16889—2008生活垃圾填埋场污染控制标准的限值。在不同粒径范围内,Cr酸提取态含量较高,占总量的16.61%～23.60%,形态较不稳定。Cd和Cu可还原态比例较高,存在一定的浸出风险。Ni、Pb、As和Ba等金属残渣态所占比例较高,重金属形态较稳定。更多还原

【Abstract】 The mineral phase composition and microstructure of fly ash（raw ash）with different particle sizes in a waste incineration plant in south China were analyzed by means of laser particle size analyzer,X-ray diffraction and scanning electron microscope. Meanwhile,the leaching toxicity and morphological characteristics of heavy metals were studied. The results showed that the incinerated fly ash particles were all less than 2 mm,and the particle size less than 38 μm accounted for 68.07%.The difference of its microstructure was large,which mostly irregular loose structure. The main chemical constituents of incinerated fly ash were CaO,Na₂ O and K₂O. CaO was mostly concentrated in large-particle fly ash,while K₂O and Na₂O were more abundant in small-particle fly ash. The main mineral phases were chloride and calcium-containing minerals,and the content increased with the decrease of particle size. The heavy metal leaching toxicity of incinerated fly ash was relatively low,only Cr leaching concentration exceeded the limit of Standard for Pollution Control on the Landfill Site of Municipal Solid Waste（GB16889—2008）. In the range of different particle sizes,the acid extractable content of Cr was higher,accounting for 16.61%～23.60% of the total,and the morphology was more unstable. The proportion of reducing state of Cr and Cu was higher,which had some leaching risk. The residual fraction content of Ni,Pb,As,Ba and other metals accounted for a higher proportion,and the forms of them were stable.更多还原