焚烧飞灰中Pb的浸出特征及预处理效果

着重研究飞灰中重金属铅的浸出行为，探讨焚烧飞灰在不同添加剂预处理下的稳定化效果。结果显示，飞灰主要重金属为铅，在液固比0.4 L·kg-1、养护7 d条件下，分别将水泥添加量从0增至40%、磷酸钠添加量从2%增至5%、绿矾从2%增至5%，铅的稳定效果均与以上添加剂的质量百分比呈正相关性。硫化钠添加量在0至0.4%内时，铅的稳定效果与其添加量呈负相关性，超过0.4%后呈正相关性。当在飞灰中添加4%绿矾、3%磷酸钠、0.5%硫化钠、15%水泥的复合添加剂时，符合卫生填埋场入场标准，且增容比最小，经济上最省。

Characteristic of leaching toxicity of lead in flying ash with pretreatment effect

The aim of this research was to explore the toxicity of lead leaching from fly ash and the pretreatment effect with different additives. The physicochemical properties and characteristics of fly ash were analyzed. The study results showed that when 4% green vitriol, 3% sodium sulfide, 0.5% sodium phosphate, and 15% cement were added to the fly ash, the content of heavy metals leaching out decreased sufficiently to meet the standard to go into a sanitary landfill. By calculating the economic costs and benefits, it was determined that this additive proportion is the most economical method.