氯化剂对超细颗粒物与重金属共生成特性的影响

以循环流化床反应器为实验平台，研究了焚烧温度为850℃下添加剂（NH₄Cl和KCl）对超细颗粒物与重金属共生成特性的影响.结果表明：NH₄Cl和KCl的存在均会降低超细颗粒物的数量浓度，但KCl的效果更佳，发挥的是阶梯式或者协同式作用.此外，添加比例为3%时对超细颗粒物数量浓度的降低最为明显.重金属Cr，Mn，Ni主要通过夹带方式形成超细颗粒物；而重金属Pb，Cu，Zn则主要通过蒸发、冷凝和吸附方式累积在超细颗粒物中.无机氯在焚烧过程中可以作为颗粒之间良好的粘合剂，促进超细颗粒物之间的成长和团聚，同时促进其表面形态的生长.此外，K的存在会促进细模态颗粒物之间的凝聚成长，使得细模态颗粒物的峰值增大，而NH₄⁺的存在会降低粗模态颗粒物的峰值.本研究可为污泥等废物热处理过程中重金属与超细颗粒物的协同控制提供借鉴.

The effect of chlorination agents on the co-generation characteristics between ultrafine particulates and heavy metals

In this paper, a circulating fluidized bed reactor was selected as the experimental platform, the effects of additives (NH₄Cl and KCl) on the co-generation characteristics between ultrafine particulates and heavy metals were investigated when the temperature was 850℃. Results showed that the number concentration of ultrafine particulates was reduced when NH₄Cl or KCl existence, however, the effect of KCl was more obvious, playing a stepped or synergistic role. Cr, Mn, and Ni entering the ultrafine particulates mainly by entrainment, while Pb, Cu, and Zn were accumulated mainly via evaporation, condensation, and adsorption. Inorganic chlorine could act as a good binder and promote the growth and agglomeration between ultrafine particulates and promote the growth and independence of its surface morphology. Besides, it has been found that K could promote the agglomeration growth of fine-mode particulates, increasing the peak value, however, NH₄⁺ will reduce the peak value of coarse-mode particulates. This study could provide a reference for the co-ordinated control of ultrafine particulates and heavy metals in the thermal treatment of sludge and other wastes.