生活垃圾焚烧飞灰重金属特性分析

对国内四个不同的垃圾焚烧厂产生的飞灰进行物理及化学特性分析.四种飞灰在颗粒尺寸分布上有相似的规律,飞灰中重金属的质量分数分析结果表明采用纯垃圾焚烧的炉排炉飞灰中的质量分数高于掺煤混烧的流化床焚烧飞灰中的质量分数.随着飞灰颗粒尺寸的减小,飞灰中重金属的浓度呈现增加的趋势.飞灰的渗滤特性表明,飞灰中Ca质量分数越高,飞灰的酸中合能力越强,且重金属的渗出率受飞灰渗滤液的pH影响大,而在碱性渗滤条件下受飞灰中重金属质量分数的影响小.

Characteristic analysis of heavy metals in MSWI fly ash

The physical and chemical characteristics of fly ashes from four MSWI plants in China were studied. The results showed that the four kinds of fly ashes had similar size distribution law, and that heavy metals content in the fly ashes of pure MSW incinerator were higher than those of the fly ashes of MSW-coal CFB(circulation fluidized bed) incinerator. The content of heavy metals in fly ash increased with decreasing particle size. The leaching characteristic showed that higher calcium content in fly ash, led to higher acid neutralization capacity. The pH of the leachate had great effect on the leachability of heavy metals in the fly ash, and that the content of heavy metals in the fly ash had little effect on it under alkali condition.