痕量元素在煤粉炉中排放特性的研究

该文分析了Cr、Pb、Mn、As、Se、Hg、Cd、Zn8种痕量元素在煤粉炉中的排放特性，得出表征痕量元素排放特性的6种数值。并根据这些数值，将元素分成3类：第1类元素：Hg；第2类元素：Pb、Zn和Cd；第3类元素：Mn；Se介于第1类元素和第2类元素之间，cr同时具有第1类和第3类元素性质。研究还发现：除Mn外，其它元素在飞灰中的富集程度随粒径减小而增加；Cr、Cd、Zn在飞灰中的相对富集程度与各自熔点成反比；Pb对烟气中活性原子Cl的亲和力大于Cd；飞灰对各痕量元素吸附机理不同；痕量元素主要分布于电除尘器飞灰和气相中；烟气中Mn和Cr含量均超过我国和欧盟关于垃圾焚烧控制标准。

EMISSION FEATURES OF TRACE ELEMENTS IN A PULVERIZED COAL BOILER

Emission features of eight trace elements(Cr, Pb, Mn, As, Se, Hg, Cd, Zn) were analyzed in a pulverized coal boiler. These elements may be classified into three groups according to six numerical values, which express emission features of trace elements: Group l:Hg. Group 2:Cd,Pb,Zn. Group 3:Mn. Se may be located between Groups 1 and 2.Cr has properties of both group 1 and 3.In addition, the smaller the diameter of fly ash is, the more the relative enrichment of trace elements (expect Mn)are. The contents of Cr, Cd, Zn in fly ashes are inverse proportional to their boiling points. Pb has a stronger affinity to Cl than Cd. Fly ash shows different adsorption mechanisms of trace elements. Trace elements are mainly distributed in fly ashes and flue gas. The content of Mn and Cr in flue gas exceed the stipulations of "Directive on the Incineration of Hazardous Wasten" in China and European Union.